Wikipedia:Reference desk/Archives/Science/2010 March 4

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March 4

In-text and Reference Citation for websites and textbooks

I'm aware of how to do in-text and reference citations for papers. But what is the format for websites and textbooks? —Preceding unsigned comment added by 142.58.132.87 (talk) 00:14, 4 March 2010 (UTC)

Usually questions about how to use Wikipedia belong at Wikipedia:Help desk rather than the Reference Desk, but I'm going to backstab us by answering: See Template:Cite web and Template:Cite book. In general the Template:Citation template is going to be flexible enough for anything at all, if you choose to read through the bazillion options. Comet Tuttle (talk) 00:28, 4 March 2010 (UTC)

If you are asking about how to cite things in your own papers (not on Wikipedia), it depends on the citation style you are using. (And for some styles, there simply is no official way to do it.) --Mr.98 (talk) 01:10, 4 March 2010 (UTC)

It's the same format as on paper. Why would it be any different just because the pages are digitized. —Preceding unsigned comment added by Telijelly (talk • contribs) 13:55, 4 March 2010 (UTC)

There are LOTS of reasons why it would be different in a digital world - for one thing you can have active links. You don't really need all that stuff about authorship, publishers, dates and page numbers when a single mouse click on the reference will magically teleport you to the actual document being cited. SteveBaker (talk) 14:45, 4 March 2010 (UTC)

That's fine until the target document moves or is deleted, which happens a lot online: then detailed bibliographical data becomes essential. --Normansmithy (talk) 14:51, 4 March 2010 (UTC)

That's why the DOI system was introduced - theoretically, as long as the document exists somewhere the DOI should resolve to the URL. —Preceding unsigned comment added by 131.111.185.68 (talk) 16:42, 4 March 2010 (UTC)

euthanasia

• Though several people have commented in good faith on this discussion, it appears that the original poster is more interested in either starting a debate or promoting a particular belief. Neither is appropriate for the reference desks. I am proactively closing this discussion down. If anyone is interested in the topic, we have articles on Euthanasia and assisted suicide for further reading. Other discussion should happen at some other website. Just not here. --Jayron32 21:21, 4 March 2010 (UTC)

This discussion has been closed. Please do not modify it.
The following discussion has been closed. Please do not modify it.
If it were an animal suffering from a severe illness people would say to put it to sleep because it was the humane thing to do. However, why must a human suffer because people are unwilling to do the “humane” thing and let them die with dignity so their suffering may end. —Preceding unsigned comment added by Thekiller35789 (talk • contribs) 00:42, 4 March 2010 (UTC) See our articles euthanasia and voluntary euthanasia. The latter says, "As of 2009, some forms of voluntary euthanasia are legal in Belgium, Luxembourg, the Netherlands, Switzerland, and the U.S. states of Oregon and Washington." The article has links to more specific articles, like Euthanasia in the Netherlands, Euthanasia in the United States, etc. Comet Tuttle (talk) 00:58, 4 March 2010 (UTC) The real meat-and-potatoes can be found in Voluntary euthanasia#Reasons given against voluntary euthanasia. Vranak (talk) 01:15, 4 March 2010 (UTC) was it by any chance a video of a blind dog that made you ask this? I thought exactly the same thing. All the comments were "do the right thing" and it struk me too how if that was a person, no one would say that. Vespine (talk) 05:05, 4 March 2010 (UTC) There are many excellent arguments in favour of voluntary euthanasia and assisted suicide, but I don't think the claim that it would place humans on the same eithical footing as animals is going to be one of the most persuasive. After all, we eat animals, but that is hardly an good argument for cannibalism, is it ? Gandalf61 (talk) 09:37, 4 March 2010 (UTC) Well, we don't generally claim that we're eating the animals for their own good. We do make that claim for euthanasia. -- Coneslayer (talk) 13:54, 4 March 2010 (UTC) We are not really killing the blind dog for his own good, we are doing it for our own convenience, and just deluding ourselves so we feel better. Googlemeister (talk) 14:06, 4 March 2010 (UTC) I'm not familiar with the "blind dog" video referenced above, and the OP didn't ask about blindness specifically. I was thinking of illnesses that cause pain, inability to eat, etc. -- Coneslayer (talk) 14:13, 4 March 2010 (UTC) We recently had to euthanise ("kill") our dog because at 12 years old, she developed a lump and started to be very slow and lethargic. She turned out to be riddled with cancer. With no way to complain, she'd probably been in considerable pain for six months or more - but as our vet said "Dogs are amazingly tough - they soldier on gracefully under the most crippling pain - but when they give up, they give up entirely." A serious effort to treat her would have cost $10,000 which we simply don't have and couldn't borrow - and would probably have only maybe a one in ten chance of working anyway. Unlike human hospitals, vetenarians don't work for free - even in emergency, life-threatening cases - and the government doesn't provide ultimate fallback health care for dogs. Because neither us nor our vet speak fluent dog - it would have been completely impossible to know whether "end of life care" (painkillers) were sufficient to provide a comfortable (albeit lingering) end. So after some debate, we paid the vet extra to come to our house, we carried the dog to her favorite spot in the back yard (she really couldn't walk anymore), settled her on her comfy dog-bed, gave her some of her favorite tit-bits (which she didn't eat) and then the vet shot her full of a strong sedative. When she fell asleep, an overdose of muscle relaxant killed her within maybe 30 seconds by stopping her heart and breathing. After we'd shed some tears, the vet took the body away for disposal. Not a bad way to go, all things considered. After a few months, we grabbed a 7 week old puppy from the animal rescue center. The old dog died after a good life and one less puppy had to be euthanised at the rescue center - a net win for dog-kind in general. It's amazing how much the act of repeatedly cleaning dog poop off your living room carpet and finding your best leather shoes reduced to 3cm x 3cm pieces all over the bedroom floor helps you get over the loss of an old friend. However, for humans who are suffering like that we have the financial support to at least make an effort to cure serious diseases and failing that, we can generally interact with the patient to give them at least some measure of relief from pain in a hospice-like setting. There is still a case for euthanasia ("killing") people who have had enough and are able to clearly say so - but there are certainly legal and ethical hurdles - as our articles indicate. It is unlikely that the loss of an adult due to some terminal disease will result in a family adopting a child as a replacement...and children that are not adopted are not routinely executed by the government. So there is zero comparison between the two circumstances. SteveBaker (talk) 14:42, 4 March 2010 (UTC) there certainly is comparison, its not all about what the family wants either. if a person lives alone and has no family. if they are blind, paralyzed , in severe pain and allergic to opiates. they should have the right to be killed. —Preceding unsigned comment added by Thekiller35789 (talk • contribs) 15:01, 4 March 2010 (UTC) Euthanasia is less the right to take your own-life than it is the right to allow someone else to take your life for you. Be that the state, a relative, a doctor or whoever. Allowing it introduces risks. Risks of systematic abuse, risks of misunderstandings, risks of coercion. On the face of it the idea of allowing euthanasia feels reasonable, feels like a good idea. Thinking through the logical and potential reality is where I (just my opinion) find it gets much more 'grey' and difficult. The key obstacle I believe is whether any party involved will be able to make a fair judgement. Relatives might want to put someone out of their misery because from the outside looking it that sort of a 'non existence' looks miserable, but what if that person doesn't want it but cannot say? What if the person said 10 years ago "if i'm in this position kill me" but once they're in the position they realise they want to live but cannot say? It's really not anything like as simple as you (thekiller35789) are seemingly making it. It's an incredibly complex issue with (for me) compelling arguments on both sides. ny156uk (talk) 17:11, 4 March 2010 (UTC) The OP persists in using this Ref. Desk to argue their support for euthanasia viz. "a person..should have the right to be killed". The question "Why must a human suffer?" finds varying answers within various belief systems and is therefore unanswerable neutrally. The OP uses a rhetoric device to fill the vacuum of that unavailable answer with their loaded contention "because people are unwilling to kill them". The underlined action is what is meant but the OP does not admit that. Instead the OP substitutes the weasel worded advocacy "do the "humane" thing and let them die with dignity". That prevarication assumes meanings of humane and dignity that only advocates of euthanasia apply in this context. "Let them die" is a transparent euphemism for kill which by definition is to prevent a life running its natural course. Claiming a justification for the killing to be "so their suffering may end" is direct advocacy of euthanasia. The OP's tendentious question is already handled by the Wikipedia reference that Vranak provided. This section should not be held open for the on-going debate that the OP seeks. Cuddlyable3 (talk) 21:07, 4 March 2010 (UTC)

Vectors

It's my understanding that, in order to prove that some quantity with direction is a vector, one must show that it is commutative and rotationally invariant. First question: are these the only two criteria? Second question: I've been able to show that the angular velocity vector is commutative, but how would I be able to show that it's rotationally invariant. Finally, how would one show that torque is a vector. Since torque is just a cross product of two other vectors, I quess this would reduce to proving that the cross product of two vectors produces a third vector, but I haven't been able to find a proof of this online. Thanks! —Preceding unsigned comment added by 173.179.59.66 (talk) 04:32, 4 March 2010 (UTC)

I'm sorry, but nothing that you wrote there makes any sense. Vectors are neither commutative (only operations can be commutative) nor rotationally invariant. The fact that the cross product of two vectors produces a vector is obvious from the definition of the cross product. I'm afraid that you're so far from understanding what you're doing that you might have to go back and relearn the basics of what a vector is. Looie496 (talk) 08:07, 4 March 2010 (UTC)

1) Sorry, I meant commutative under addition. 2) How can a vector not be rotationally invariant? That would mean an equation like F = ma would depend on the choice of axis. 3) To my knowledge, the cross product is defined as a determinant of some sort. The result of this computation produces something of the form ai + bj + ck, but that doesn't mean it's a vector.173.179.59.66 (talk) 08:35, 4 March 2010 (UTC)

Looie is right. What you are talking about is usually refered to by physicists as covariant under rotations. The Vectors are covariant under rotations and the vectorial equations are invariant under rotations. Dauto (talk) 19:42, 4 March 2010 (UTC)

That's funny, because this entire time I was mixing covariant and invariant, really sorry about that! —Preceding unsigned comment added by 173.179.59.66 (talk) 20:25, 4 March 2010 (UTC)

Have a look at http://en.wiki.x.io/wiki/Vector_%28geometry%29#Vectors.2C_pseudovectors.2C_and_transformations . The components of vectors should transform like coordinates under rotations. It is my understanding that a cross product is actually a pseudovector but don't quote me on that. —Preceding unsigned comment added by 157.193.173.205 (talk) 08:31, 4 March 2010 (UTC)

I think you should close this question and ask it again on the math reference desk. Those guys will nail this one very quickly. SteveBaker (talk) 14:12, 4 March 2010 (UTC)

Something doesn't need to have direction to be a vector. The definition of a linear vector space is http://en.wiki.x.io/wiki/Vector_space#Definition Basically the space must have closure, it must be distributive in the scalars, scalar multiplication must be associative, Addition must be commutative and associative, there is a null vector and an inverse under addition for each vector. For instance operators can be treated as vectors.

On another point vectors can be commutative, in a space of Real vectors all vectors are commutative because < A | B > = < B | A > * = < B | A >

82.132.248.82 (talk) 23:13, 4 March 2010 (UTC)

Who can make the definition of "Space" understandable to users with a high-school education?

I have chased down every (blue) referenced term in both the Space page and across numerous pages in a vain attempt to gain an understanding of the true understanding of the nature of 'space'. I accept the mathematical assumptions made in much the same way as a theoretically dimensionless point is defined for the purposes of function and equation. However, the original "Space" page left me with no descernable improvement in my understanding of both the existential nature of 'space' nor the efficacy of the many clumsy analogies that are proffered in support of meaning. I have read much of the arguements regarding the nature of 'expansion' with reference to space and the balloon analogy is a case in point: To declare that the balloon represents the expanding Universe and then stick an ant on the outside to argue that its corporal structure is unaffected by the expansion of the balloon universe is not helpful. The balloon analogy only works when assuming that the Universe is represented by the balloon; to add an ant (on the outside) is to break the very conventions of the analogy itself by introducing an ant (presumably) outside the Universe!

What would help users like me (and there are many - I assure you) is a comprehensive AND comprehensible explanation of the fundamental nature and function of space in both its physical and theoretical applications. For instance:

1. If space is a vacuum, or a volume in which nothing exists; how does gravity bend it?
2. If space is truely a state of non-existence, a vacuum within which nothing exists; surely this definition is based upon the attribute of 'existence' being the sole property of matter, as theories abound of zero-point quantum energy fields and some empirical evidence to support the idea that the Universe is filled with energy in all manner of modes and quantities, etc.
3. If space is merely a mathematical species of frames or matrixes that provide quantative relevence to various behaviors and transformations at macro, micro and quantum scales - what really causes space lensing??
4. The elevated circles within which the aether was argued and eventually discarded were not successful in transmitting a truely understandable analogy of this conclusion to the satisfaction of those of us that work with the real Universe. Such ideas may be erroneous but they are also intuitive - to existing generations as well as to our venerable ancestors. Wikipedia is at its best when it conveys to the masses a wholesome and digestible explanation of these endemic misunderstandings.

Finally, quantum physics has introduced us to the concepts of granularity and "forbidden states" that lie between manifest energy levels at sub-atomic scale; however, (in my clumsy attempts to consolidate their analogies and explanations) space appears to be devoid of any such constriction. We are left to ponder such (intuitive) conundrums as:

1. Is space confined to a resolution that must obey quantum rules?
2. Can string-theorists simply magnify the dimensions of particle physics by a billion and claim to have discovered a true and final base for the smallness of things?
3. Does matter really move; or does it simply emerge, first in a quantum spacepoint (A), then sink back into the quantum sea only to manifest again in Spacepoint (B) - that just happens to be the adjacent location closest to (A) - thereby giving the illusion of motion yet simply being a series of manifest existences bounded by the granularity of space; time; and energy/matter?

Scientists have done a wonderful job of improving upon the once clumsy definitions provided for the concept of "Energy" in this Wikipedia; I hope that a comparable attempt will be made to de-mystify the nature of "Space".

GPCViriya (talk) 09:46, 4 March 2010 (UTC)

Wow, that's a lot to take on. Let me just answer one small part of it by saying that space is not a pure vacuum. It certainly contains small densities of ordinary matter, and quite possibly other forms of matter such as dark matter. StuRat (talk) 13:53, 4 March 2010 (UTC)

OK - well, let me try to answer some of these:

1. If space is a vacuum, or a volume in which nothing exists; how does gravity bend it? - In general relativity, matter bends space and bent space produces the illusion of gravity. That's only one view, but it's the prevailing one. Why matter bends space is probably an unanswerable question. It just does.
2. If space is truely a state of non-existence, a vacuum within which nothing exists; surely this definition is based upon the attribute of 'existence' being the sole property of matter, as theories abound of zero-point quantum energy fields and some empirical evidence to support the idea that the Universe is filled with energy in all manner of modes and quantities, etc. - Space (as described by physicists and cosmologists isn't the same thing as 'vacuum'. It's kinda like the sheet of paper on which a diagram is drawn. The diagram is matter and energy - the paper is "space". It's the underpinning of what we perceive as "distance" or "position". The physicists concept of "space" is present even inside solid bodies. Now, if we're talking about "space" as (say) an astronaut might talk about it (the gaps between solid things that's mostly vacuum) then that's really something different. The "vacuum" of deep space isn't really empty - there are a few atoms per cubic meter, also lots of photons and all sorts of other exotic things like virtual particles.
3. If space is merely a mathematical species of frames or matrixes that provide quantative relevence to various behaviors and transformations at macro, micro and quantum scales - what really causes space lensing?? - Gravitational lensing can be thought of as the consequences of bent space (see question (1), above). Space is bent - light takes the shortest path through it and the shortest path across a bent surface isn't a straight line (kinda like aircraft flying long distances across the Earth travel along "great circle" routes because they are less distance than "straight lines"). To our senses - which can't directly comprehend the curvature of space, the light appears to bend.
4. The elevated circles within which the aether was argued and eventually discarded were not successful in transmitting a truely understandable analogy of this conclusion to the satisfaction of those of us that work with the real Universe. Such ideas may be erroneous but they are also intuitive - to existing generations as well as to our venerable ancestors. Wikipedia is at its best when it conveys to the masses a wholesome and digestible explanation of these endemic misunderstandings. - The aether theory was just wrong. It's a discarded hypothesis because it simply doesn't fit the facts. It may be intuitive - but it's a useless explanation because it doesn't explain the behavior of light.

Quantum physics questions:

1. Is space confined to a resolution that must obey quantum rules? - There is a minimum unit of distance which (I suppose) you could think of as the "resolution" of space.
2. Can string-theorists simply magnify the dimensions of particle physics by a billion and claim to have discovered a true and final base for the smallness of things? - No. String theory is much more complicated and radically different from the 'normal' view of particle physics.
3. Does matter really move; or does it simply emerge, first in a quantum spacepoint (A), then sink back into the quantum sea only to manifest again in Spacepoint (B) - that just happens to be the adjacent location closest to (A) - thereby giving the illusion of motion yet simply being a series of manifest existences bounded by the granularity of space; time; and energy/matter? - No, matter moves.

SteveBaker (talk) 14:08, 4 March 2010 (UTC)

Regarding the balloon analogy: the surface of the balloon is analogous to space. As the balloon inflates, the surface expands. The ant represents a point (or a set of points near each other) on the surface of the balloon. Zain Ebrahim (talk) 14:17, 4 March 2010 (UTC)

It may be easier if you don't think of matter as something that's "in" a vacuum, but rather think of it as part of the nature of the vacuum. If you look at general relativity by itself, without any matter, it's still a highly nontrivial theory—you have gravitational waves that propagate around and interact with each other, just like any other kind of wave might do, even though there's nothing "in" the space. In the Standard Model of particle physics, which is the best current theory of everything other than gravity, everything other than gravity is like this too. The "particles" are various kinds of oscillations of the vacuum. This is enshrined in the Standard Model in a fairly deep way, through the concept of spontaneous symmetry breaking. The nicely symmetric fundamental vacuum state of the Standard Model is unstable, so, at low enough energies, the vacuum ends up in a different, stable state at some "distance" (in the landscape of possibilities) from the center of symmetry. The particles of everyday life are small oscillations around that state, and they're only indirectly related to oscillations around the unstable center. When particle physicists say "vacuum", they mean a small neighborhood of an equilibrium state, or, in other words, the vacuum proper and all of the low-energy particles and their interactions. For example, when they talk about a "landscape of string vacua" and trying to find a vacuum that corresponds to our world, that's what they mean.

At least this means we don't have to understand space as a container for matter; we only have to understand it as a thing unto itself. Unfortunately, that's the best you're going to get right now. Space behaves like a multidimensional continuum that can be deformed in various ways, and nobody knows anything more than that. There have been many extremely speculative attempts to give it another structure, which go by the name of pregeometry. Probably the best developed of those ideas is spin foam, about which I know nothing beyond what's in the Wikipedia article. -- BenRG (talk) 02:37, 5 March 2010 (UTC)

Thank you,
(StuRat): You are saying that space is seldom (or ever) found in a pure state of vacuum; however, I understand that matter - ordinary, dark or exotic is not included in the definition of the nature of space, it simply exists at a certain point in space, manifesting its own family of characteristics and behaviors. Therefore, you are describing vacuum as a condition relating to the ratio of matter to the volume of space - not describing the fundamental nature of space (in itself).

Thank you, (SteveBaker):

1. The unanswerable question, (as how matter bends space) does not eliminate the underlying arguement of my question. My premise was; presuming that space (in its own nature) has no attributes, how can any thing bend it? When one refers to the change in shape (from flat to bent), under the influence of gravity; it is assumed that space (itself) has been influenced by the proximity of matter, which possesses an attribute of mass, which manifests a force called gravity, and has deformed space to reflect the influence of this force upon the very fabric of space.
2. Your comments (in 2) address my question in point 3. I assume that by paper, you mean physicists rely upon the paper to illustrate the positions and/or co-ordinates occupied by particles within a certain arrangement in space? This accords with my own understanding - that space is used as a foundation for the deliniation of such properties as; position, motion, etc. These properties are not ascribed to space, but to the particles, etc,. that are included in the diagram. Your extra comments regarding the condition of inter-stellar space returns to your earlier comments regarding the nature of a vacuum and do not directly address the nature of space.
3. In 3, you return to the point, that space is bent and light takes "the shortest path through it" thereby attributing some characteristic to space that is both bent and exerts an influence upon light to respond to this condition by following a bent path. However, this characteristic of space is left undefined albeit your contention that, whatever it is - it is bendable.
4. I presume that you are referring to the particle/wave characteristics of light when you mention that the aether hypothesis has been proved wrong. I have no arguement with this; however, it does help to illustrate my point regarding the unintended confusions created by using analogies that do not eliminate the underlying inference for just such a medium. By this, I mean; any and all mention of bent-space has the immediate effect of creating the idea of space as a thing, or medium within which the behavior of particles, under certain conditions, can only be explained by pertubations or deformations in the fabric of that space, medium or thing. Creating a vacumm to demonstrate the passage of light without the support of a medium does not eliminate the possibility that space, itself, has the characteristics of a medium. Simply removing all other particles from a region in space does not change the nature of the space itself. A vacuum is not devoid of space any more than the volume contained within the body of a sub-atomic particle is devoid of space, regardless of its mass.
5. To my quantum physics questions, you peaked my interest when you mentioned the existence of a theoretical minimum distance; then you simply discounted any significance to this assertion when you stated that "matter moves". Clearly both cannot be right. If matter was required to move only a fraction of the "minimum distance", it could not - then we would have to deal with all the potential and/or kinetic energies that may still require transition. If the matter was to move only 1 unit of the minimum distance; it could only achieve this (not by an analogue re-positioning) but by a cessation of existence in one location and a subsequent manifestation at the next, or nearest location (as any smaller movement would be prohibited).
6. String theory may appear to be more elaborate and complex than particle theory, but it still must address the fundamental characteristics that have been thus far observed. In essence, (to the ear of a layman like myself); string theory has replaced the elementary particle with a field of strings, at a greatly reduced magnitude in both scale, momentum and inertia, and used the more numerous unique characteristics of a string (as opposed to a particle) in their analogies - to ascribe the various configurations and resonant conditions in the stings to represent the observed momentums and behaviors of higher species of elementary units.

I am in no position to question the verasity of the science, experimentation, and theoretical conjecture that is contained in either the Standard Model nor the fledgling String Hypotheses; however, neither side has provided the general population with any working analogies that withstand even the most precursory analysis. Although such examples are not meant to explain the complete picture; they actually pollute the mind of the thinker when these analagies are pushed too far.

Zain Ebrahim's opening comment is a case in point: Given that the analogy of the balloon is representative of the fabric of space and its inflation indicative of the effects of expansion: the ant may represent either a point, or several points in the aforementioned space. Assumed to be a point - the ant experiences no change; as a point is considered to be dimensionless and therefore immune to any change in scale happening around it. Assumed to be a collection of points where the feet touch the surface of the balloon - the ant will find its feet becoming ever more widely spread the longer the expansion of the balloon continues. These are necessary considerations that require the layman to first accept that an ant, outside the balloon, is still in the Universe that has been defined as the surface of the balloon. In fact, we need to discount both the volume of air within the balloon AND the volume of air outside the balloon to focus upon the real efficacy of using the balloon surface as an analogy for an expanding Universe. Introducing the ant invalidates the analogy completely and all subsequent arguements regarding the state of the ant serve only to obfuscate the intended meaning of the exercise. I think the original arguement was concerned with applying a fixed, scalar reference inside an expanding universe. What changes are observed to the space, matter and the arrangement of matter within that space and the influence that the expansion of the universe was having upon both the nature of the matter AND the measurements of their locations and dimensions relative to each other. I presume that the balloon analogy will not be helpful in resolving that one.

Finally, BenRG brings in a veritable plethora of ideas that both illustrate and clarify the nature of my arguement and afford me the chance to zoom in on the specific point that bothers me and is keeping me from appreciating the work that theoretical physics is doing:

1. The dicotomy between vacuum and matter is not the crux of my questions regarding the nature of space. Any and all descriptions of the interaction between particles (both mass-carrying and force-carrying) may be conceived of as occurring in space without the need to interact with the space in any way. For example; the number of particles, the ratio between their energy levels and their freedom to move within a defined space can be used to calculate their density and even their pressure within a confined space and this can be simply illustrated by analogy without referring to the nature of space - apart from the volume included in the observation. Such a description treats space as a mathematical matrix or yard-stick by which to measure and subsequently observe inherent characteristics of both quantity and quality or behavior. Such observations and calculation do not ascribe any qualitative characteristics to space, only volume is used to provide scale and quantity.
2. BenRG goes on to provide a whole list of potential waves and particles with which to describe phenomena that do not rely upon the presence of space to contribute to their behavior at all. Regardless of our choice to refer to gravity as a wave, a particle, or a wavefunction; any choice is valid and is all that is required to describe the effect it will have upon another particle. The trajectory of a photon is effected by its interaction with a graviton, gravity wave, or the mass of an attendant atomic or sub-atomic particle, which is included in the observation, and can be predicted, tested and described without the use of space as anything other than a location in which to observe and measure the interation. The Standard Model contains sufficient species of particles to carry any and all of the fundamental material and force-characteristics that exist in the Universe bounded by space, without having to assign any of these behaviors to space itself.
3. In essence, we do have to think of space as a "container"; with no unique characteristics nor interactions with matter or force, and useful only as a field of observation, manifestation and quantification of all other species of behavior and existence. Any distortions to this "multidimensional continuum" are by inference alone, they can be explained by interations between particles and/or wavefunctions that describe the inherent characteristics and behaviors of specific modes of energy, manifesting on any level, from the quantum sea of virtual-quarks up to the distribution of galaxies within the Universe.

In conclusion; I see no need to include space as a discreet entity of existence, replete with unique characteristics that are essential to the orderly interaction of all other entities contained in the Standard Model. It appears simply to act as an inert background for manifest existence and only makes an appearance (as the 4 dimensions) when observations and measurements are required. So far, science has failed to convince me (an uneducated but rational humanbeing) that space is a term that describes anything other than the mind's ability to differentiate both scale and distance in reference to an observation of discreet objects.

Respectfully,

GPCViriya (talk) 09:33, 5 March 2010 (UTC)

GPCViriya, you have not sufficiently educated yourself to apply "common sense" arguments to the definition of space. Much of what you say is easily contradicted by referring to any rudimentary cosmology text. For example, you seem to think that space has no attributes; while many would argue that TIME has no attributes (and is, as you said about space, merely a form of measurement), space has attributes, as demonstrated e.g. in the moments between the Big Bang and the completion of the inflationary epoch. Space expanded by something like 10 to the 50th power in a fraction of a second, even though it was a vaccuum at the time. So, at least according to all reputable cosmologists, space indeed has attributes regardless of what it "contains." Seriously: read a book rather than applying "common sense." 63.17.82.123 (talk) 03:25, 6 March 2010 (UTC)

I agree with '63. We aren't here to debate your "reasoning" - you asked a question, you got good answers - as best we know, they are true. Please don't argue with the respondants - if you think you know better then you didn't need to ask in the first place and you are not allowed to start debates here. However, you certainly don't know better. The problem is that "Common sense" is the worst possible tool in our mental arsenal for dealing with the very large and the very small. This 'common sense' that we seem to be born with is simply an evolutionary instinct and we're not evolved to deal with the universe at the quantum-scale and at cosmological-scales. The first thing you need to do in understanding this stuff is to dump common sense. It doesn't "make sense" that space is curved - but it doesn't have to make sense to be true. The results of physics experiments and mathematics are the truth - and the tools of the scientific method and mathematics are the only way to get any kind of useful understanding of this stuff. Common sense is completely misleading. SteveBaker (talk) 18:35, 6 March 2010 (UTC)

True: I asked a question, I received answers and I questioned the answers, using the rudimentary education I have and attempting to highlight where my (obviously incorrect) interpretations were leading me. I did not set out to argue; I set out to illustrate my lack of understanding and my difficulties with the analogies, which is all I can address, as it has been stated from the beginning, that I do not know better, do not possess the tertiary education to do the math and hoped to find out more from you learned gentlemen through dialogue. I apologize if my clumsy attempt to analyze these answers has caused any offense - I meant none and made no attempt to hide my ignorance on these matters. I would like to know something about these fundamental concepts, yet when I ask on these kinds of forums; I am either flamed with abuse for being ignorant or ignored completely. I appreciate that these concepts are complicated and do not lend themselves to simple analogy. I appreciate your efforts in trying to enlighten me; however, I seem to have insulted you by highlighting my continueing confusion. My 'reasoning' was an attempt to illustrate how your answers raised ever more conflicts within the confines of the analogies that have been put forward as working analogues of what the true meanings are. Devoid of high mathematics, I am left only with what I think of as reasoning and which I applied to your elaborations in an attempt to illustrate my suspicion; that some analogies give rise to more confusion than they resolve. I'm sorry my approach has insulted you, I will refrain from seeking answers on this talk-page; however, before I go, could someone be so kind as to redirect me where I can go when the knowledge expounded on Wikipedia is too elevated to be understood by people with nothing but common sense to quide them? I am a keen user of Wikipedia; however, I often lack the depth of understanding to appreciate the explanations given. I use the blue links that often highlight the terms I don't understand and I spend many happy hours chasing my ignorances down to the n'th degree. This time; I arrived at "Space" - a word that I presumed I had a reasonable handle upon - but no. In my enthusiasm; I searched the community portal for a suitable place to make my enquiry. I knew I had no right to take part in the discussions that are directly attached to the "space" page, and I was led to this forum, thinking I was on the right track. Once again, I apologize for any irritation I have caused. Sincerely, GPCViriya (talk) 08:26, 7 March 2010 (UTC)

Inverted crater on Mars

I came across this image from the Mars Reconnaissance Orbiter. The image description calls it an inverted crater. What is an inverted crater? Is it just a round-shaped plateau that just happens to look like a crater? According to inverted relief, natural processes on Mars can cause features like river beds that were once depressions to end up above the surface. Is this another example of that? —Preceding unsigned comment added by 72.94.164.21 (talk) 12:33, 4 March 2010 (UTC)

[1] (the official NASA version of the Yahoo story with actual facts and stuff) says that the crater was originally a regular crater that filled up with sediment which compacted and became harder rock than the landscape from which the crater was formed - then erosion eroded away the softer crater walls and the surrounding land to leave the compacted sediment as this "inverted crater". A similar kind of thing happens on earth when a volcano erupts in soft material - then the lava hardens into a really solid rock like basalt - and then the soft ground around it erodes leaving a column of harder basalt. The name for those things escapes me for the moment - but I'm sure someone here will tell us. SteveBaker (talk) 13:33, 4 March 2010 (UTC)

Were you possibly seeking Intrusion or Volcanic plug? -- 124.157.247.225 (talk) 14:53, 4 March 2010 (UTC)

Inverted relief —Preceding unsigned comment added by Telijelly (talk • contribs) 13:52, 4 March 2010 (UTC)

American Cat Scans

Because of the sterotype that americans are fat, there was always this joke going around that amerians would get stuck on cat scan machines. Is it true than quite the contrary, the manufacturers made the machines large to accommodate fat people, but in doing so really thin and small people were unable to use the machines because it was scanning air around them and giving false resulte? —Preceding unsigned comment added by Gordanginton (talk • contribs) 13:26, 4 March 2010 (UTC)

No. First, I doubt the premise of your question. Second, the machines can scan whatever is within their circumference irrespective of whether that happens to be air or flesh. --Tagishsimon (talk) 13:32, 4 March 2010 (UTC)

My wife used to work as a nurse in the radiography department of a large hospital - she said that they had on occasion cat-scanned premature new-born babies - which are about the smallest thing you'd ever consider trying to scan - and that worked perfectly. So no - this is flat out not true. SteveBaker (talk) 13:36, 4 March 2010 (UTC)

does she still work as a nurse, just not in radiography anymore? What department is she working in now? I'm asking because I know someone in a similar situation and wonder what a good switch is from the radiography department. Thanks. —Preceding unsigned comment added by 84.153.250.71 (talk) 14:49, 4 March 2010 (UTC)

I work for a medical device company whose name doubles for a type of screwdriver, and in recent years our marketing materials have been completely written to emphasize the usefulness of our new products in handling "difficult patients" -- this is marketing-speak for fat/overweight/obese however you choose to describe it. Simply put, for something like an ultrasound it just takes more juice to get a good picture when there's more "material" between the sensor and the object you wish to image. 61.189.63.188 (talk) 14:37, 4 March 2010 (UTC)

You work for Flathead?? ike9898 (talk) 14:45, 4 March 2010 (UTC)

Or maybe Stanley ? StuRat (talk) 15:58, 4 March 2010 (UTC)

But there must be limitations on that method. Specifically, doesn't the near flesh get an increased exposure level ? StuRat (talk) 15:55, 4 March 2010 (UTC)

Patient size is a bigger factor for an MRI machine than for a CAT scanner, because the device benefits a lot more from having the sources and sensors close to the subject. MRI machines are notorious for causing claustrophobia. Looie496 (talk) 17:09, 4 March 2010 (UTC)

I was going to ask about that. When I was in grad school, the neuroscience/cognition folks had 3 sizes of MRI machines. I think they had one for humans, one for smaller primates, and one that was smaller yet (dogs? rodents?). I was wondering if the smaller machines worked better on the smaller animals, or if they were just less expensive. -- Coneslayer (talk) 17:13, 4 March 2010 (UTC)

I would think that 1 human sized MRI device would be cheaper then 3, regardless of the size of the others, but if there was a low % of machine downtime, it makes more sense. Googlemeister (talk) 17:30, 4 March 2010 (UTC)

A rodent-scale MRI can get resolution down to a tenth of a millimeter, as I recall, which is 10 times better than you get with an ordinary human MRI, so there are definite advantages to having a separate machine if there is money to buy it. Looie496 (talk) 17:52, 4 March 2010 (UTC)

The logical conclusion, then, is that to do a first rate job of analyzing a foot problem, they should saw it off, run it through a rodent MRI machine, then sew it back on. Among other benefits, this approach would likely reduce the number of people requesting scans for brain tumors. :-) StuRat (talk) 19:01, 4 March 2010 (UTC)

Side issue: Was that a correct use of the word steriotype? Americans have afterall really become on average quite overweight. Dauto (talk) 20:59, 4 March 2010 (UTC)

I've heard stereotype used to mean "any characteristic ascribed to a group of people, whether true or not", so it sounds correct here, to me. StuRat (talk) 22:40, 4 March 2010 (UTC)

The only limits are upper limits. Throughout the 1980s and 90s, most US CAT scan machines had an upper limit capacity of 300 lbs: many radiology depts or imaging centers would refuse to image someone who was heavier. Partly it was fitting in the cylinder and partly it was the warranty limit on the moving parts of the machine. There are no lower limits to size except resolution limits. alteripse (talk) 21:11, 4 March 2010 (UTC)

Compressing Water

Can water be compressed? How much of a space saving will be achieved from compressing water to it's maximum —Preceding unsigned comment added by Harodeuam (talk • contribs) 14:05, 4 March 2010 (UTC)

Yes, but not to any significant degree. See our article on the properties of water for details, but note that at a pressure of 400 atmospheres, water retains over 98% of its original volume. — Lomn 14:13, 4 March 2010 (UTC)

The article mentions oceans at 4 KM. I wonder if there is any info about the compression at around 11 KM, the approximate depth of the Mariana Trench? As I recall from physics class, the reason objects can be crushed at great depths is not so much that the water is "denser", but that there's a column of water several miles high crushing it. But I would think that weight would also impact the density of the water itself - even if only to a small extent? ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:40, 4 March 2010 (UTC)

The article also says that the compressibility decreases as the pressure increases. So if you get 1.8% compression at 4 km depth, the compression at 11 km must be more than that, but less than 5%. --Anonymous, 01:21 UTC, March 5, 2010.

Assuming that doesn't push you past a phase transition to one of water's many allotropes, I think you mean. Not that I've checked whether any of those are much denser, or whether the pressure at 11 km is even close to enough. --Trovatore (talk) 01:26, 5 March 2010 (UTC)

I don't think water has more than one liquid phase; if it did at oceanic pressures I'm sure I would've heard about it somewhere. --Anonymous, 05:15 UTC, March 6, 2010.

I think BBugs may have also been referring to the fact that the pressure at 11 km will be more that 11/4 of the pressure at 4 km because the density of the water that is responsible for the pressure is increasing with depth. You need to solve a differential equation to determine the density as a function of depth give the compressibility (or density) as a function of pressure. 124.157.249.168 (talk) 23:58, 7 March 2010 (UTC)

I got a related quesiton guys. If you don't store water, but only the hydrogen and the oxygen that you could combust together to produce it, then can you compress THOSE gasses in a way that is equivalent to compressing water? e.g. if you have an x cubic meter room, can you get x + y cubic meters of water to flow out of it, for an appreciable amount of y, not because you had tanks of compressed water in it (which would be very difficult, and the y would be tiny) but because you had tanks of compressed hydrogen and oxygen in it, and combined them to produce your water flow? 84.153.250.71 (talk) 14:44, 4 March 2010 (UTC)

Water has 2 grams of hydrogen per 18 grams of water, which is 18 millilitres, (See molecular formula and atomic weight). By Avogadro's Law, 2 grams of hydrogen under standard pressure and temperature would occupy 22.4 litres, which is 1,244 times the volume of the water it would form when burnt with atmospheric oxygen. The oxygen required would take up 11.2 litres, if it is not available locally. The burning of hydrogen will also produce very high temperature steam, which would then need to be cooled down. So in answer, no, it is not practicable to carry just the hydrogen. CS Miller (talk) 15:15, 4 March 2010 (UTC)

Let's see... at standard temp and pressure, it would take 33.6 liters to store 18 grams of water-equivalent. Assuming that we didn't vary temperature, then, you've got to crunch 33600 milliliters to 18 milliliters to get to water volume equivalence. That would be storing the gases at over 1860 atmospheres. Clearly, this is less practical than just storing water. — Lomn 15:04, 4 March 2010 (UTC)

I'm sorry, I don't get the "upshot". If I have an x cubic meter room underwater (no ambient oxygen source) and I want to store MORE than x cubic liters of water in it, is it better to try to compress water (maybe also cooling it as much as possible short having it freeze and expand) or to try to store it separated, as compressed, cooled gases hydrogen and oxygen? Assume you can just take the heat from combustion and boil the outside water with it... 84.153.250.71 (talk) 15:23, 4 March 2010 (UTC)

p.s. obviously there is no need to store water in a room underwater. I'm just askin'.. 84.153.250.71 (talk) 15:23, 4 March 2010 (UTC)

I doubt it. Reacting 29.5 litres (2kg) of liquid hydrogen with 14 litres (16kg) of liquid oxygen will produce 18 litres of water. I don't have the density of frozen hydrogen or oxygen handy. CS Miller (talk) 16:05, 4 March 2010 (UTC)

There could be a reason. If you want drinking water and you're under the ocean, you'd need to desalinate it and sterilize it before drinking. Whether the apparatus to do this takes up more space than the stored water depends on the duration of the stay as well as the technology used. This is a similar trade-off to space ships either carrying water or recycling water from breath, urine, and poo (when the water comes out brown, it's time to change the filter). StuRat (talk) 15:51, 4 March 2010 (UTC)

(ec)If you read Lomn's response, he is saying that in order to get the hydrogen content of water down to the same volume as the water (before even thinking about the oxygen), you'd need to produce an ungodly amount of pressure. So yes, if you can produce, say 3000-some atmospheres of pressure, you might be able to store it in a smaller volume as independent gasses (though the water itself would likely have compressed a bit more at that point). At a certain point, hydrogen would enter its metallic phase which is basically as a compressible as it gets without triggering fusion. Since you're not going to produce that amount of pressure just to store water, we can safely say you're better off just storing the water. —ShadowRanger ^(talk|stalk) 15:52, 4 March 2010 (UTC)

Oxygen condenses at room temperature under sufficient pressure, doesn't it? It will become essentially incompressible at that point too. I have no idea what that point is, though. --Tango (talk) 04:45, 5 March 2010 (UTC)

No. According to our article, the critical temperature of oxygen is about −118 Celsius. Above that temperature, no amount of pressure can liquefy it. Still, sure, you can compress it to the point where the atoms are more or less touching, and even though it's not a liquid, it will still be almost incompressible at that point. --Trovatore (talk) 06:25, 5 March 2010 (UTC)

If you put oxygen under great pressure, it would behave like a liquid, but you could not get a surface on it. So the resistance to pressure would climb. If you just compress water enough you will get a form of ice, at about 2000 atmospheres. Forming metal by compressing hydrogen or oxygen is much more difficult needing millions of atmospheres of pressure. Ice III has a density of 1.16. So 15% above water. Graeme Bartlett (talk) 09:02, 5 March 2010 (UTC)

What type of medical specialist does this?

This might seem like a request for medical advice, but really it isn't...

The type of medical insurance I have allows me go directly to a specialist without first going to a primary care physician to get a referral. I have an injury which I suspect is something along the lines of a injured upper back muscle (either a small tear or separation from the bone). So, what sort of physician specializes in this sort of problem?

ike9898 (talk) 14:43, 4 March 2010 (UTC)

Orthopedic surgery --Normansmithy (talk) 15:08, 4 March 2010 (UTC)

It's really impossible to decide yourself what the actual cause of a given sensation is. I had a similar shoulder problem, which felt like a joint or tendon malfunction. My doctor diagnosed it, however, as muscular adhesions, and sent me to the physiotherapist. The physio cleared it right up. Figuring out which specialist is appropriate is exactly the job of a primary care physician. -- Finlay McWalter • Talk 21:00, 4 March 2010 (UTC)

No argument, but I'm sure you can see the appeal of possibly reducing the number of doctor appointments you have to go to. Of course, if I initially go to the wrong specialist, that won't save anybody any trouble! ike9898 (talk) 21:46, 4 March 2010 (UTC)

Well, that's the point of visiting a primary care physician. -RobertMel (talk) 19:45, 5 March 2010 (UTC)

Plasma

How is Plasma made? —Preceding unsigned comment added by Harodeuam (talk • contribs) 14:45, 4 March 2010 (UTC)

Are you referring to blood plasma or Plasma (physics), a state of matter comprising partly ionized gas? Blood plasma is made up of lots of different components from different sources: proteins, hormones, glucose, water, etc. Plasma (physics)#Common artificial plasma has information on making the other sort. --Normansmithy (talk) 15:14, 4 March 2010 (UTC)

(EC)Plasma (gas) or Blood plasma (the non-cell part of blood)? (there are other plasmas on the diambiguation page, but these two are the most likely). I suggest looking at those articles. -- Flyguy649 ^talk 15:16, 4 March 2010 (UTC)

Sun size

Daft question i'm sure but...is the sun noticeably 'larger' with the naked eye when you're closer to the equator? The moon obviously varies in how far away it is and it's very noticeable when it's larger, but sitting here in sunny (for today) England fully aware that those near the equator are 'closer' to the sun I was wondering whether that effect is noticeable. I'd recommend some people try but staring at the sun isn't that great for your eyes. ny156uk (talk) 17:22, 4 March 2010 (UTC)

Well, let's think about the scales involved. The sun is somewhere between 90 and 100 million miles away. How much larger do you think it would look if you were 4,000 miles closer (.004%)? This would not be a large enough difference to be noticeable to your average human. Also, the distance from the sun varies by much more then that amount throughout the year because the orbit is not a perfect circle. The moon on the other hand is only about 250,000, so 4,000 miles is around 2%, and might be noticeable. Googlemeister (talk) 17:26, 4 March 2010 (UTC)

(EC) There would be no difference detectable. The earth's mean radius is 6371 km. The mean distance of the earth to the sun is 149.6 million kilometres. Ignoring the 23° tilt of the earth's axis, someone at the pole is one earth radius farther from the sun than someone at the equator. That's 0.004 percent. I doubt there is a noticeable difference in the size of the sun from perihelion to aphelion. -- Flyguy649 ^talk 17:32, 4 March 2010 (UTC)

Also, the width of the Earth may vary by 4000 miles from the poles to the equator, but would vary far less between the equator and England. I'd guess maybe 1500 miles (or 0.0015%), but invite others to do the math. Note that the variation isn't linear, meaning the width of the Earth varies far less from the equator to 45 degrees than from 45 degrees to the poles. StuRat (talk) 17:37, 4 March 2010 (UTC)

File:Lunar libration with phase2.gif Image removed to reduce page load size. Franamax (talk) 21:21, 5 March 2010 (UTC)

Note also that the eccentricity of the Moon's orbit (some 42 000 km variation) dwarfs the equator-to-pole variation and the horizon-to-overhead variation (6 300 km). Between that and the Moon illusion (note that said illusion also holds for the sun, which has no appreciable difference in observable size, so there really is a psychological component), I'm not sure the naked eye would actually observe the difference in an equatorial versus England-based viewing. — Lomn 17:47, 4 March 2010 (UTC)

I posted an gif file that shows the aparent movement of the moon throughout a month (libration) that shows clearly how large is the change in aparent size of the moon due to the eccenticity of its orbit. Dauto (talk) 18:23, 4 March 2010 (UTC)

Interesting animation. It appears to show the Moon rolling slightly upward over the course of the month, which confuses me since one side of the Moon always faces the Earth. Is this just part of a little wobble, or is this an illusion, too ? StuRat (talk) 18:57, 4 March 2010 (UTC)

Libration should have all the details, but it's quite real. The Moon rotates on its axis at an even rate, but it orbits the Earth at a varying rate (due to the orbital eccentricity). The net effect is that the Moon alternately lags and leads, showing nearly 60% of its surface over the course of a sidereal month, even though only the same 50% is visible at any given point in a sidereal month. — Lomn 19:03, 4 March 2010 (UTC)

Is that additional 10% entirely due to libration, or is a small portion also due to having a slightly different view of the Moon from different locations on Earth ? StuRat (talk) 19:26, 4 March 2010 (UTC)

Some very small fraction is gained by moving around the Earth (or by waiting for the Earth to revolve; same effect), but the vast majority is due to the libration. I'd guess it's a difference of three orders of magnitude, though I haven't tried to work the math. — Lomn 21:53, 4 March 2010 (UTC)

Great pace - 3 answers in less than 15 minutes! Yeah figured it wasn't likely but wasn't sure of the numbers. Thanks everyone for their input - just came to me on the way home and figured what the hell i'll ask. ny156uk (talk) 17:44, 4 March 2010 (UTC)

Follow-up question for any who might know: My intuition would be that the size wouldn't change at all due to relative distance (as noted, the delta in the distance is minuscule compared to the total distance), but that it might vary a bit based on changes in the atmospheric lensing. I'm not a physics guy, so I'm probably wrong, but wouldn't the appearance be distorted the further you are from the equator, depending on the season? Perhaps slightly larger in the Northern hemisphere's winter and with a slight disturbance to its shape? Probably not all that observable on a human scale (particularly given the problems with looking directly at the sun), but more measurable than the effect already addressed? Similarly, the shape would change somewhat over the course of the day, since at sunrise and sunset it would be passing through a greater volume of the atmosphere than it does at solar noon? Anyone know if that has an effect greater than, say, a couple millimeters in observed size? —ShadowRanger ^(talk|stalk) 18:14, 4 March 2010 (UTC)

Atmospheric effects ca definately deform the observed shape of the sun. Look at that picture from the green flash article. Dauto (talk) 19:37, 4 March 2010 (UTC)

So presumably for some seasons and latitudes you'll get a visible effect even at midday. After all, above the Arctic circle the sun spends some time effectively permanently rising (or setting, however you want to view it). Still curious if places like London or Manhattan see any such effects (outside of sunrise and sunset), but that at least partially satisfies my curiosity. —ShadowRanger ^(talk|stalk) 19:52, 4 March 2010 (UTC)

I've taken the liberty of thumbnailing the images posted in this thread; the rest of the reference desk should be have to be subjected to such large and distracting images. User:Curious Cactus 20:43, 4 March 2010 (UTC)

Would you believe "should not"? --Anonymous, 01:30 UTC, March 5, 2010.

One further point. Do you notice that the Sun looks smaller in July than in January when it is 3,000,000 miles (5,000,000 km) closer? Then why would you expect to notice when it is 4,000 miles closer due to being seen from a different place on the Earth? --Anonymous, 01:32 UTC, March 3, 2010.

Highway-side notches

There's these weird notches in the pavement that alert a driver to if they are drifting too far to the left or right side of the highway. I want to know how they work, and if we have an article about them. Mac Davis (talk) 17:47, 4 March 2010 (UTC)

Rumble strips. -- Coneslayer (talk) 17:48, 4 March 2010 (UTC)

Thanks. I've noticed that if you drive backwards on them no noise is made, while if you drive forward on them, noise is loud. How could they be designed that way? Mac Davis (talk) 17:57, 4 March 2010 (UTC)

I believe (not 100%) that this is due to the way in which some strips are cut at an angle. If you drive forward, the wheel slowly (relatively speaking) descends the slope, then hits the sharp cut at the far side with the full force of your forward momentum, which jolts both the wheel itself and the attached suspension, creating a louder sound. In reverse, the only impact is the fall off that same ledge onto the slope, so the primary impact is only as strong as the momentum produced by gravity in a fall of an inch or so; your reverse momentum continues with minimal impact.

Of course, when you're going forward, you're usually going faster, so you're going to get more noise in any event, since you rarely go fast in reverse. But for some rumble strips, the slope-and-wall design would account for your experience. —ShadowRanger ^(talk|stalk) 18:04, 4 March 2010 (UTC)

Ah, that makes perfect sense. I should have thought of that. It seems like the notches are not very wide compared to the tire circumference though. I don't know if the tire would really go "up" or "down" a slope. Mac Davis (talk) 18:29, 4 March 2010 (UTC)

Parts of the tire would. They're flexible. So no, usually the tire never reaches the bottom (unless you're really low on air), but it still descends enough to trigger the effect mentioned. —ShadowRanger ^(talk|stalk) 18:30, 4 March 2010 (UTC)

Popcorn

My bag of Boston's Lite Popcorn advertised that it was "whole grain" -- what does that even mean? That they don't remove that brown chaff, because it doesn't seem like anyone removed it (other than corn pops, but that's not popcorn). DRosenbach ^{(Talk | Contribs)} 18:27, 4 March 2010 (UTC)

Whole grain means the bran, endosperm and germ of a plant are found in the product. Mac Davis (talk) 18:31, 4 March 2010 (UTC)

I wasn't asking for the definition of "whole grain" in general, but for its application to corn. DRosenbach ^{(Talk | Contribs)} 18:34, 4 March 2010 (UTC)

It probably means someone in the marketing department had a clever idea. You need the kernel intact in order to trap the moisture to enable popping in the first place. Whole grain is big, so they decided to cash in by mentioning it (despite the fact that it was already the case). At best a "non-whole grain" popcorn might be able to trim a tiny part off the "point" of each kernel (where it connected to the cob) without compromising structural integrity, but I doubt any effort is made to keep or remove it, they just do whatever is most efficient to strip the kernels. —ShadowRanger ^(talk|stalk) 18:34, 4 March 2010 (UTC)

So it's a scam -- just as I thought. Thanx! DRosenbach ^{(Talk | Contribs)} 18:36, 4 March 2010 (UTC)

Well, it's a scam if they are trying to imply that their product is any healthier than other popcorn. On the other hand, it might be useful to remind people that popcorn is a whole grain snack, when comparing with other snacks, like pretzels, where some may be whole grain and others may not be. Of course, the good the extra fiber does you probably pales in comparison with the harm all that salt and grease does. StuRat (talk) 18:49, 4 March 2010 (UTC)

As a good friend of mine says: popcorn is merely a vehicle for butter and salt. Vespine (talk) 23:26, 4 March 2010 (UTC)

You can get hot-air popcorn poppers that add no fat, and you can refrain from adding salt, and then you have a healthy snack that's as tasty as Styrofoam packing peanuts. +Angr 23:49, 4 March 2010 (UTC)

Plus, it's cariostatic (and that was a nice take on it, StuRat...never considered that). DRosenbach ^{(Talk | Contribs)} 04:54, 5 March 2010 (UTC)

How intelligent are beavers

Moved from Talk -- Coneslayer (talk) 18:26, 4 March 2010 (UTC)

How intelligent are beavers? Has anyone done comparative tests? The article on Beaver dams suggests that their dam building is hardwired in but I guess that still makes them the second most intelligent species on the plnet when it comes to building dams, but how do they do in more general things? KTo288 (talk) 18:25, 4 March 2010 (UTC)

I think your premise is based on a skewed view of the definition of intelligence. Bees and other wasps are able to construct virtually perfect three dimensional hexagonal hive structures, but I don't think that makes them smart. Weaver birds construct ridiculously cool nests...but really, all bird nests are cool. It would probably take you a long time to make one, and if likely wouldn't be as neat and sturdy, and you are using two hands with 5 fingers each, while birds generally do it with a beak. Intelligence has nothing to do with this. DRosenbach ^{(Talk | Contribs)} 18:30, 4 March 2010 (UTC)

Intelligence has more to do with pattern recognition and creation based on learned patterns than following instinctive behavior. Mac Davis (talk) 18:32, 4 March 2010 (UTC)

It's not hard to see that a certain amount of very simple but 'logical' thought has to go into the logistics of harvesting trees and building a dam. But,what makes you think that other rodents don't have similar cognitive abilities? Just because squirrels don't have an instinctive ability and need to build damns doesn't mean that they couldn't solve very simple problems. Squirrels often come up with clever ways of defeating anti-squirrel bird feeders. Chipmunks store a surprising amount food for the winter.

A lot of that is trial and error, and not planning things out ahead of time, but it's not like beavers don't make mistakes.

Sometimes beavers fell trees and then later realize they can't get them to the dam site. (I wonder if they're capable of feeling frustration.) Sometimes they start a dam in one place and then abandon the site and build in a slightly different place on the same stream. Sometimes they use a rock or tree as a major structural piece that isn't really tied down well at all.

What makes beavers seem so outstandingly intelligent is their determination and hard work. They make lots of screw-ups, but they keep at it until they get it right. Then you come along in the morning and see their completed dam and imagine that they built it right the first time. APL (talk) 19:37, 4 March 2010 (UTC)

Our article North American Beaver unfortunately does not refer to the intelligence of the species, but does note that in one experiment, researchers placed a cassette tape player, playing the sound of running water, in a field, and the beavers ran over and covered up the tape player with mud and wood to try to make a dam. I believe the editor who introduced this information may have held the view that beavers are idiots. Comet Tuttle (talk) 18:34, 4 March 2010 (UTC)

It is sometimes difficult for us to distinguish between intelligence and instinct. Spider webs also seem amazing, but they are apparently made via a complex set of instinctual actions, as opposed to higher thought and problem solving ability. A more obvious case is birds that "talk". At first it might seem that they are intelligent and holding a conversation, but in short order you realize they just repeat sounds they hear without any knowledge of what they mean. StuRat (talk) 18:43, 4 March 2010 (UTC)

Intelligence is task-specific, so your inquiry cannot really produce any useful results. Suffice to say that beavers can respond to varying conditions fairly well. My dad works as a civil engineer, and there are often issues with beavers causing problems in his municipality. They can make do in a semi-urban landscape, until wildlife control steps in. Vranak (talk) 18:51, 4 March 2010 (UTC)

Thanks for the responses (sorry for asking in the wrong place). From the responses above I guess I'm concentrating too much on the results of what they do rather than how they do it.KTo288 (talk) 21:46, 4 March 2010 (UTC)

Not very. I reckon, in a game of poker, you could easily lick a beaver. —Preceding unsigned comment added by 79.76.171.183 (talk) 22:27, 6 March 2010 (UTC)

But in a game of Monty Hall, pigeons beat humans. (ref: news) Imagine Reason (talk) 22:54, 6 March 2010 (UTC)

PAD vs PADI (peptidylarginine deiminase)

Reading some papers on peptidylarginine deimmanses has gotten me into a fluster! The enzyme citrullinates arginine to citrulline with some interesting consequences, in most the literature the enzymes are abbreviated to PAD, a few refer to them as PADI. However a few papers imply that the PADI is the gene sequence that encodes for PAD.

Some clarity on the matter would be appreciated as I don't want to be refering to genes as if they were proteins...

129.31.206.253 (talk) 19:22, 4 March 2010 (UTC)

I should add the wiki pages aren't helpful, titles refer them as PADIs whereas references refer to them as PAD MedicRoo (talk) 19:26, 4 March 2010 (UTC)

Usually gene names and protein names are the same, with the gene name in italics and the protein Capitalized. However, sometimes there are nomenclature differences between species, e.g. human and rodent. Searching at the Entrez database, shows Padi3 in rats and PADI3 in humans. Pad3/PAD3 are listed as synonyms. I suggest that the PADI vs PAD is probably due to either some minor disagreement amongst researchers or different names in different species. Also, HUGO is the human gene nomenclature database. Similar results can be found there. -- Flyguy649 ^talk 19:38, 4 March 2010 (UTC)

PAD doesn't seem like a good abbrev, to me, since it's also an abbreviation for so many other things, including at least one item in the medical field: Peripheral artery disease. So, if a medical journal has a title "New research on PAD", which do they mean ? StuRat (talk) 19:57, 4 March 2010 (UTC)

If you think that's bad you should check out APC, specifically the four distinct meanings in molecular biology/biochemistry.131.111.185.68 (talk) 23:32, 4 March 2010 (UTC)

StuRat, it is a minor problem since identifying which protein is the subject of the article is usually apparent from other words in the title. If that doesn't make it clear, the abstract will. Clicking on an article found in Pubmed goes to a page with the abstract and a link to the article. Also using an advanced search can help limit results. For example, I used to read papers discussing AP2. The one I was interested in is involved in vesicular trafficking; the other is a transcription factor. I could usually tell by the title which it was. (Both those articles are terrible, by the way). -- Flyguy649 ^talk 16:30, 5 March 2010 (UTC)

But isn't the cost of that extra character worth not having to add more search parameters or read the abstract to tell if you have the right one ? StuRat (talk) 17:57, 5 March 2010 (UTC)

I know what you mean, but it's hard to do in practice. Which one retains the old shortform? I think these problems are less likely to happen with new genes, since every gene now has a unique nomenclature and journals generally require the use of official nomenclature. But genes and proteins that predate genome sequencing are somewhat "grandfathered". Scientists are very resistant to change... traditionally, naming rights go to the earliest publication. But if two labs come up with different names at the roughly the same time, it can become a bit of a pissing contest and it may take years for one form to become dominant. Also, it happens on occasion that scientists don't realize that they are studying the same protein or gene, so there are multiple names for that reason. Or independent nomenclature develops in different species. Sometimes unification works -- e.g. smad proteins is an amalgamation of mad (Drosophila melanogaster) and Sma (Caenorhabitis elegans). Then there are no real rules preventing a gene name from being the same as a short form for a disease or other acronym/short form. Reviewers will likely discourage authors from coining an acronym/shortform if there's an existing well-known use of the same. I guess the short answer is that logic doesn't really prevail in reality! -- Flyguy649 ^talk 21:25, 5 March 2010 (UTC)

I take it that biochemistry lacks something equivalent to the International Astronomical Union, which resolves such naming and classification issues in astronomy. I'm glad astronomers are better organized, or we might still call the planet Uranus by it's original name, George. StuRat (talk) 22:12, 5 March 2010 (UTC)

Unknown beetle that looks like a large ladybug

I found a beetle on my wall today, and am trying to determine what it is. Unfortunately I don't have a picture because, as I was watching it, it attempted to fly away but had a fail and fell down behind something. Now I can't get to it. It looked just like a ladybug, however, except larger. It appeared to be about 1 cm in diameter, shaped like a half-sphere(ie, not a flat insect). It had the second pair of flight wings like ladybugs and many other beetles do. I didn't get a good look at what its head looked like due to the angle it was at and how large the round "shell" wings were, and when I tried to walk closer it fell down, but I believe there may have been long antennae present. Does anybody know of any beetles that resemble this? —Preceding unsigned comment added by 69.243.51.81 (talk) 20:24, 4 March 2010 (UTC)

You'd have to give your physical location to get a useful answer. There are millions of insect species, most of which are confined to extremely limited ranges. —ShadowRanger ^(talk|stalk) 20:37, 4 March 2010 (UTC)

If it looked like a large ladybug, it probably was. It's size just means it's engorged on aphids, a normal part of the ladybugs life cycle at this time of year. User:Curious Cactus 20:40, 4 March 2010 (UTC)

Ladybugs -- Coccinellidae -- are beetles. 1 cm in size is at the upper end of their size range, but there are species that reach 1 cm size. There are also other beetles with approximately "half sphere" body shape; for example, some Chrysomelidae and a number of water beetle species/genera from several families. --Dr Dima (talk) 21:27, 4 March 2010 (UTC)

The OP never denied that ladybugs are beetles. In fact, he confirmed it when he wrote "ladybugs and many other beetles". +Angr 21:32, 4 March 2010 (UTC)

I'm from maryland, so about halfway up the eastern coast of the usa. When I looked up ladybugs, most of the sources I found said that they didn't usually grow past 5mm, so finding one twice that size was what made me think it must be a different species. 69.243.51.81 (talk) 22:31, 4 March 2010 (UTC)

There are very many different species of 'ladybugs' or Coccinellidae beetles (5,000+ worldwide, 450+ in North America), and some are indeed up to 10mm in diameter. It's probably impossible for us to be sure what this one was without a good picture, but Harmonia axyridis (aka the Asian lady beetle, Japanese ladybug or Harlequin Ladybird) seems like a good candidate. 87.81.230.195 (talk) 14:19, 5 March 2010 (UTC)

This is the conclusion my friend and I came to last night. She has those kind in her house, and she routinely sees them as large as I saw the one yesterday, so we think it may have come home in my bag from her house. Thanks for your help. 69.243.51.81 (talk) 16:55, 5 March 2010 (UTC)

Is there any life on the planet Earth?

If we were looking at Earth orbiting a star, is there anything about it which would indicate that it had life? How close would you have to get to detect life? 92.29.76.62 (talk) 20:52, 4 March 2010 (UTC)

You could detect radio signals from earth that would show there was people with that technology. User:Curious Cactus 20:58, 4 March 2010 (UTC)

There's also an argument that the mere presence of abundant atmospheric oxygen would indicate life. The lack of oxygen wouldn't make life impossible, but according to Neil deGrasse Tyson on the Colbert Report a few days ago, oxygen is too prone to reacting with other elements to remain stable without living things to produce it (e.g. cyanobacteria). I doubt this theory is universally accepted, but it's another opinion on the matter.

Your question does require some parameters though. How close are the observers? Martians could see the light from cities on our night side and deduce it was artificial. How technologically advanced are they? We're improving our ability to examine distant stars all the time; as recently as a few years ago we couldn't actually detect planets outside our solar system, now we can detect particularly large ones and even divine some of their properties (mass, distance from their star, certain facts about their atmosphere, etc.). —ShadowRanger ^(talk|stalk) 21:13, 4 March 2010 (UTC)

It's tough to guess how the Martians would think. If the Martians don't know about aerobic life, and instead regard oxygen as a deadly poison, it might not immediately occur to them that high oxygen levels were an indicator for life. Their scientists might spend years debating what sort of unusual geologic process is causing our high oxygen levels. APL (talk) 22:07, 4 March 2010 (UTC)

Martians could also see the greening of each hemisphere's temperate region when it's spring occurs. They might not immediately think of photosynthesis and chlorophyll, but maybe they would. StuRat (talk) 22:32, 4 March 2010 (UTC)

I won't say it is impossible, but I think it is unlikely one could see terrestrial city lights from Mars. The total luminosity of civilization, as viewed from Mars, would be less than 1/1000th of a bright star, and you'd have separate that from reflected sunlight and moonlight. That would be a technically challenging thing to resolve directly. Dragons flight (talk) 06:28, 5 March 2010 (UTC)

1/1000 corresponds to about 7.5 magnitudes. I'm not sure what you mean by "a bright star" exactly, but you must mean at least magnitude 1, I sure, so we're talking no dimmer than magnitude 8.5. That's easily visible with a human eye looking through binoculars. If you look when Mars is at opposition and it's a new moon, the Earth's disc should be completely dark (except near the limbs where some light will be refracted by the atmosphere) and seeing down to mag 8.5 through binoculars shouldn't be at all hard. With a decent telescope, you would have no difficulty at all. --Tango (talk) 06:39, 5 March 2010 (UTC)

In response to Cactus: Intelligent life is different from "life". Radio signals might give the game away, but the question of how to detect low complexity life is quite different. —ShadowRanger ^(talk|stalk) 21:24, 4 March 2010 (UTC)

Of course detection of intelligent life is one indication of "life". My understanding of the state of SETI technology is that it is unlikely that even the most advanced receivers we use today could pick up our own transmissions, with the possible exception of our highest powered military radars, were they being emitted from as far away as the next to nearest star. This was mentioned in a Google Tech Talk on SETI, but I would like to find a better reference and add it to the SETI article. The article currently says: Furthermore, the earth emits considerable radio radiation as a byproduct of communications such as TV and radio, and these radiations would be easy to recognize as artificial due to their repetitive nature and narrow bandwidths. If this is typical, one way of discovering an extraterrestrial civilization might be to detect non-natural radio emissions from a location outside our solar system. I think most people believe it would easy to pick up Earth's television emissions from anywhere within a 73.5 light year radius. 124.157.247.225 (talk) 00:42, 5 March 2010 (UTC)

With regards to people asking about the observers; the OP is specifying if we could detect that life. So, I think we can assume the observes are oxygen-breathing, and at a technology level equal to ours. The question of distance is still unanswered, though. Vimescarrot (talk) 22:29, 4 March 2010 (UTC)

If we were looking at a duplicate Earth, the basic answer is that we could identify intelligent transmitting life from within a radius of a few dozen light years(maybe even a few hundred, depending on the power and directionality of the broadcast) if we were looking in the right direction, but we probably couldn't detect the planet itself if it wasn't in our solar system. If the life isn't using electricity, we'd be blind to anything outside the solar system.

In the next few years (once our interstellar planet detection technology improves a bit so we can detect Earth-sized planets and determine the composition of their atmosphere accurately), we could probably identify the presence of an Earth-sized world with an oxygen atmosphere in a our immediate stellar neighborhood (a few dozen light years in any direction) which would indicate, but not prove the existence of life. —ShadowRanger ^(talk|stalk) 23:00, 4 March 2010 (UTC)

Life was detected on earth with the Galileo and LCROSS probes, but of course these probes were quite close (well within our own solar system). -- Coneslayer (talk) 12:40, 5 March 2010 (UTC)

It is worth mentioning that the most sensitive radio telescope in the world is not sensitive enough to detect a broadcast transmission from the most powerful radio transmitter in the world at the distance of the nearest star (4 light years). Unless a radio signal is being beamed in a very tight beam, it's unlikely to be detectable across interstellar distances assuming the people doing the listening and transmitting are at roughly the same level of technological development as humans. SteveBaker (talk) 20:11, 5 March 2010 (UTC)

Well, but here you're talking about a single transmission, rather than the whole sea of radio emissions from the whole planet, right? I don't know whether he was correct, but I recall a claim by Larry Niven that the Earth emits as much (artificial, I think) radio flux as a small star, and I think we do see small stars in the radio sky. So on the (admittedly shaky) basis that both these statements are correct, we might hope to detect that there is intelligent life via radio observation, even if we can't resolve a particular message. --Trovatore (talk) 20:26, 5 March 2010 (UTC)

See our article Extraterrestrial_life. --Kvasir (talk) 20:36, 5 March 2010 (UTC)

Council house with air conditioning

A council house near me has what looks like air-conditioning. The house is still owned by the council. The climate in the UK does not require air-conditioning. What could explain this? Thanks 92.29.76.62 (talk) 20:56, 4 March 2010 (UTC

Isn't it obvious? The previous residents must have had it installed. Maybe they just had spare money and decided they wanted to try it. Also, the UK does have a climate that would warrant air conditioning in the summer. Especially since global warming it getting worse and worse. User:Curious Cactus 21:02, 4 March 2010 (UTC)

Methinks you do not know what a council house is. It was installed quite recently. 92.29.76.62 (talk) 22:04, 4 March 2010 (UTC)

What kind of air conditioning? Window units or central air? If window units, are they present in every single flat? If they're only present in some, then I'd guess the tenants had them installed at their own expense. I agree it's unlikely a city government would pay for air conditioning for all council house tenants in a climate like the UK's. On the other hand, you only said it looks like air conditioning. Is there anything else it could be? +Angr 22:15, 4 March 2010 (UTC)

A/C doesn't only lower temperatures, it also lowers humidity, and you do sometimes get high humidity there, as on a foggy day. (There are also dehumidifiers, which only lower humidity.) While I doubt if anyone in the UK would die from a lack of A/C, they could certainly be more comfortable at certain times of year with it. Now the question is whether they should pay, at taxpayer expense, to make poor people more comfortable. Some would say yes, others would say no. I would tend to answer differently depending on why they are poor. If they are a drug addict who can't hold a job, then hell no. If they are a paralyzed veteran who was wounded in combat, then yes. StuRat (talk) 22:21, 4 March 2010 (UTC)

Re people dying from lack of A/C: Newspapers do report old people dying of heat in un-air-conditioned homes during hot summers, actually. I don't know if they specified exactly what the cause of death was. Vimescarrot (talk) 22:26, 4 March 2010 (UTC)

Vimescarrot: Heatstroke. Ks0stm ^(T•C•G) 22:37, 4 March 2010 (UTC)

You only get fog on about two or three days in winter - it is clear that you are uniformed about the matter that you are taking about. 92.29.76.62 (talk) 23:21, 4 March 2010 (UTC)

Well, if you can't specify the location any more precisely than "UK", you can't expect us to know the weather very precisely, either, now can you ? StuRat (talk) 03:09, 5 March 2010 (UTC)

The above applies to all of England and Wales, and probably most or all of Scotland. 78.151.93.38 (talk) 14:26, 5 March 2010 (UTC)

So, no place in the UK gets fog more than 3 days a year, and always in winter ? I don't believe that. StuRat (talk) 15:01, 5 March 2010 (UTC)

It would be unusual to have more than three foggy days a year, or to have a foggy non-winter day, exccept perhaps in late autumn. I know from other North Americans that people who've never been here believe the UK is full of swirling fogs - an idea I suppose they've got as a legacy of old Sherlock Holmes films, and that we're an island. And no, we don't get fogs in summer, LOL! You may be using San Fransisco as an incorrect analogy - I understand they gets lots of fogs there due to that climate and topography, which we do not share. 78.146.208.26 (talk) 20:18, 8 March 2010 (UTC)

Great! Now my question is completely ruined and I will never get a sensible answer but several paragraphs of inevitable bickering and worse-than-useless uninformed speculation! 92.29.76.62 (talk) 22:47, 4 March 2010 (UTC)

Welcome to every day on the Wikipedia Reference Desk. Enjoy your stay. User:Curious Cactus 22:52, 4 March 2010 (UTC)

In your question, you basically asked us to speculate on something we have no experience of. We haven't seen the house you're talking about, nor are we in charge of what appliances are installed in it. Unless you provide more information (like answering the questions I asked above, or taking a photograph of the building and posting it here), uninformed speculation is all you can hope for, because quite frankly, it's all your question in its current state can possibly be answered by. +Angr 23:27, 4 March 2010 (UTC)

It is customary and normal etiquette to only answer questions you have knowledge of, rather than just guessing from several thousand miles away. 84.13.22.99 (talk) 00:57, 5 March 2010 (UTC)

Yes but clearly most of the respondents did feel they have sufficient knowledge to be able to offer informed speculation. There's no requirement you actually live in the UK to answer a question concerning the UK. As it stands, the OP still hasn't provided any information to ascertain whether it's possible the tenant installed these airconditioning units which is surely a key point. It's customary and normal etiquette to accept it when people are trying to help regardless of whether you agree with the answer particularly when the question calls for extensive speculation because of the nature of the question and the failure of the questioner to provide any real information even when asked. I would add that I believe VimeCarrot lives somewhere in the UK & Angr lives in Germany, so not 'several thousand miles away'; and I have no idea where User:Curious Cactus lives, do you? Also for all the complaints of pointless bickering, part of the reason this question has gotten offtrack is because of the OP's complaint. Nil Einne (talk) 01:57, 5 March 2010 (UTC)

Are you talking about a window A/C, or a central A/C?. I'm not from the UK, but if it's a window unit, I don't see what's wrong with Cactus's answer. They're cheap and easily installed, someone could have done so on a whim, or because they're fussy or medically sensitive to temperatures or air quality, or whatever.

Central A/C might be more of a mystery, if you're sure that's what it is. In a commercial building I would just assume that there was some technology in the building, like a server-room, that needed A/C, but that doesn't work in a residence. APL (talk) 02:24, 5 March 2010 (UTC)

I was reluctant to say this given the OP's complaints but screw it. It's perhaps worth remembering that many A/Cs can function as heatpumps and would probably be the most efficient form of electrical heating. Here in NZ, they're extensively promoted as such given that many of our houses have extremely shit insulation and many places lack gas heating it probably makes sense. Of course many may use them in the summer as well and this is useful in quite a few parts of the country like Auckland. I appreciate things are different in the UK, but it seems easily possible that the same thing would be an added incentive for some people to have them installed. This ref [2] says they're starting to become standard in new urban developments for example. Nil Einne (talk) 02:41, 5 March 2010 (UTC)

How sure are you that it is a council house and not an ex-council house? The right to buy scheme has resulted in a very large number of council houses now being in private hands. --Tango (talk) 04:49, 5 March 2010 (UTC)

Its absurd that people from the other side of the Atlantic who may never even have set foot in the UK in their lives or even know what a council house is should believe that they can and should answer a question about a UK council house. 89.242.242.77 (talk) 10:04, 5 March 2010 (UTC)

I don't understand why you are so bemused by this. Occupants of council houses have great flexibility in making improvements to them, although the council can insist that it they are kept in good order, and that changes are reversed when the occupants leave. If the current occupants plan on staying for the long-term, they might well decide it is worth installing air conditioning (depending on the system, it may also be possible to take it with them if they move). While most occupants of council houses are on low incomes, it isn't essential; they can stay on if their income increases, and in the few areas where there is a surplus of council housing, they are readily available to anyone. Warofdreams talk 11:50, 5 March 2010 (UTC)

Oh no! Government-owned, subsidized housing is completely unknown out here in the Rest Of The World, How will we ever answer your question about why a residential unit might need a piece of equipment that looks like HVAC unit??!?!?!?

Ok, I think I've figured out the answer you're fishing for, Here you go : "Because the [Political Party] is pandering to the lazy and shiftless poor, and needlessly wasting your tax dollars providing unnecessary luxuries to the [ethnic group] poor!" Does that help? APL (talk) 15:25, 5 March 2010 (UTC)

Nearly all the people I've met who live in a council house have been foul mouthed ignorant thugs with chips on their shoulders who hate middle-class people. Although that does not so much apply to expensive areas like London, where middle-class people like Vivienne Westwood often exploit the cheap accomm. 78.146.208.26 (talk) 20:44, 8 March 2010 (UTC)

A tangental query, but what areas have a surplus of council houses please? I thought there were long waiting lists for them. Thanks 78.151.93.38 (talk) 14:07, 5 March 2010 (UTC)

Certain deprived areas in the north and Scotland, which have a lack of demand for housing in general, have surplus council housing. Here, for instance, is a recent document from West Dunbartonshire Council noting that they have around 350 council properties with no demand, while here is something similar from Salford. Of course, it may be that these houses are run down, and with a little investment would be in demand - describing them as "surplus" might well be a way to justify selling them or demolishing them and selling the land, to make the council some quick cash. Warofdreams talk 15:00, 5 March 2010 (UTC)

If I was in charge I would demolish half of them and use the land to create parks and mini-nature reserves, and thus turn them into attractive areas people want to live. 78.146.208.26 (talk) 20:44, 8 March 2010 (UTC)

The what-looks-like air conditioning is a large metal box on the ground within a few inches of the wall of the house containing a large fan, with pipes from it going into the house. It is painted exactly the same colour as the walls of the house, suggesting it was installed at the expense of the local government who own the house. I wonder if it might be required for something like a kidney dialysis machine, but in the past they required an extra room to be built on to the house to contain the machine, and there is no extension on that small house. Perhaps those machines have got smaller in recent years. Council houses are lived in by people who are poor, particularly in that part of the country, and I am sure they would not buy air conditioning on a whim as they are not needed here. The house is still definately owned by the local government. I think its practically impossible that its some sort of cooling equipement for computer servers, as the local council would not give permission, and the people are very likely to be poor, uneducated, and irresponsible. 78.151.93.38 (talk) 14:24, 5 March 2010 (UTC)

Wow, lots of stereotypes there. There are many legitimate reasons why responsible, educated people can find themselves to be poor, such as divorce (and thus needing to support two households on an income that formerly only supported one), illness (making work impossible), etc. And perhaps the people in that house have slightly improved their financial situation, enough to afford A/C, but perhaps not enough to afford better housing. If they needed to get permission from the council to install the A/C, one of the requirements might well have been that they make it blend in as well as possible, including matching the paint color.

Modern dialysis machines are completely self contained and require no external cooling. There could also be a medical necessity for A/C, such as if the person is morbidly obese and thus more prone to heatstroke. Or, they could have severe allergies which prevent them from cooling the house by opening windows. I suggest you contact the council directly, and ask them for the details. StuRat (talk) 15:18, 5 March 2010 (UTC)

Air_source_heat_pumps would be a possibility - these are being promoted as a more efficient replacement for existing electric storage heater or oil heating systems (typically when mains gas is not available). As such the local council could easily have installed the system (grants are also available from central government under energy efficiency programmes). From a UK resident. 94.197.138.254 (talk) 18:28, 5 March 2010 (UTC)

energy from earth's rotation

i'm sure it must be unfeasable, but can't see exactly: why can't we derive power from the angular momentum of the earth? 109.246.247.147 (talk) 20:58, 4 March 2010 (UTC)

See? Do you mean Sea? User:Curious Cactus 20:59, 4 March 2010 (UTC)

corrected to we 109.246.247.147 (talk) 21:17, 4 March 2010 (UTC)

We can derive power from the rotation of the Earth, that's what tidal energy is. Tides are produced by the rotation of the Earth relative to the Moon and, to a lesser extent, the Sun. StuRat (talk) 21:01, 4 March 2010 (UTC)

this is correct, but doesn't quite answer the question i had in mind, which is why is it not possible to transfer momentum from the earth's rotation directly into torque or some other means of driving a earth-based engine? 109.246.247.147 (talk) 21:17, 4 March 2010 (UTC)

Virtually all power generation is based on energy level differentials. In order to derive power *directly* from the angular momentum of the Earth (as opposed to indirectly through the tides), you'd need to find a way to connect it to something not experiencing that momentum. And anything you attached it to would be giving up its kinetic energy to provide the power; deriving energy from the Moon for instance would cause a gradual orbital decay (and/or reduce the rotational speed of the Earth). The tides (and tidal power) are doing basically the same thing, it's just on a scale so low that it has minimal effect on our own rotation and the Moon's orbit. Of course, I'm not a physicist, so I'm sure I made some minor errors in my explanation, but I believe the basic point is sound. —ShadowRanger ^(talk|stalk) 21:20, 4 March 2010 (UTC)

The real reason is angular momentum conservation. BTW the moon's orbit is actually rising, not decaying. Dauto (talk) 21:30, 4 March 2010 (UTC)

I always thought that an orbit can "decay" either upwards, until the object leaves orbit, or downward, until it crashes. StuRat (talk) 22:24, 4 March 2010 (UTC)

Obviously, since the Earth is slowing down. The moon takes up much of that energy (another part is dissipated as heat, and yet another part should actually lift the Earth into a higher orbit around the sun...). --Stephan Schulz (talk) 21:34, 4 March 2010 (UTC)

I would say true, but not obvious.Dauto (talk) 21:38, 4 March 2010 (UTC)

Hmm. If the moon's orbit decays and the Earth slows down, you need a really big energy sink somewhere. --Stephan Schulz (talk) 21:42, 4 March 2010 (UTC)

Heat?Dauto (talk) 21:45, 4 March 2010 (UTC)

Yep. The tidal energy pretty much all turns into heat eventually, either in the water or in the Earth's core, mantle, and crust. StuRat (talk) 22:05, 4 March 2010 (UTC)

It was a rhetoric question but thanks for answering anyways.Dauto (talk) 03:10, 5 March 2010 (UTC)

We had pretty much the same question recently about attaching a gear to the earth Earth GearVespine (talk) 21:43, 4 March 2010 (UTC)

What you want is a 'Gyrogenerator' as seen here in the Museum Of Unworkable Devices. (Second one down on that page.)

Perhaps someone better at crunching the numbers could tell us if this would actually work. (Assuming sufficiently frictionless equipment, of course.) APL (talk) 22:28, 4 March 2010 (UTC)

I think you are confusing energy and momentum. Steve will be along soon to explain it. --Tango (talk) 05:04, 5 March 2010 (UTC)

acidosis

what is the treatment for urinary acidosis other than iv bicarbonate which is just a temporary fix. no other problems can be found to cause this. the person is not diabetic. (this is a hypothetical question.. im not asking for the cause but the treatment. —Preceding unsigned comment added by Thekiller35789 (talk • contribs) 21:36, 4 March 2010 (UTC)

Unfortunately, we cannot recommend treatment options, even in the hypothetical. Please read the Wikipedia:Medical disclaimer. Instead, you should seek, or advise your friend to seek, the advice of a qualified medical professional who can see and treat your friend in person. --Jayron32 22:18, 4 March 2010 (UTC)

contribs) 22:39, 4 March 2010 (UTC)

Also see the reference desk guidelines on the matter, which explains what we do and don't answer here specifically. Acidosis is a particularily good example of why we have these guidelines, because there are different possible causes, and the best treatment is often to eliminate the underlying cause. We cannot hope to diagnose the underlying cause of a specific instance in a specific person, and then proscribe the best form of treatment. If someone you know does have acidosis, they should discuss it with a medical professional who has the access and training to evaluate and treat the condition, rather than asking a random group of people on the internet.Buddy431 (talk) 22:28, 4 March 2010 (UTC)

no one i know has acidosis and neither do i . im just interested in it. it sounds to me like their is no real treatment if no underlying cause can be found ?

This looks like a homework question to me. The answer will be in your text book —Preceding unsigned comment added by 79.68.242.68 (talk) 00:46, 5 March 2010 (UTC)

There is no disease called urinary acidosis. You may be mixing up renal tubular acidosis, which comes in several varieties caused by many different underlying conditions. Treatments also vary according to the underlying condition. alteripse (talk) 02:03, 5 March 2010 (UTC)

im 45 years old and not in school, lol. the acidosis im taking about is when your urine has a low ph. —Preceding unsigned comment added by Thekiller35789 (talk • contribs) 02:39, 5 March 2010 (UTC)

There are uncountable reasons why a person's urine would have an abnormally low pH, and without a proper medical examination to determine the underlying cause, it would be absolutely impossible to recommend a course of treatment for it. That's why we don't answer questions like this; if its idle curiosity Urine#pH contains a very brief discussion of the issue, and articles like Acid-base homeostasis discusses the physiological pH levels in general. You could follow links from there to see what you find. If you have specific concerns about your own urine or the urine of people whom you know, seek a doctor. --Jayron32 06:27, 5 March 2010 (UTC)

I thought you were a 19 year old who was worried about what would happen to you if your mum died [3]? Incidentally if you don't know anyone with acidosis, why the sudden interest [4]? Nil Einne (talk) 20:02, 6 March 2010 (UTC)

zoonoses from dogs

Besides rabies, are there other zoonoses that humans can get from dogs and v v ? Googlemeister (talk) 21:58, 4 March 2010 (UTC)

Kennel cough User:Curious Cactus 22:53, 4 March 2010 (UTC)

The kennel cough article says nothing about transmission between dogs and people. Deor (talk) 23:05, 4 March 2010 (UTC)

Who said that Wikipedia articles are necessarily comprehensive? DRosenbach ^{(Talk | Contribs)} 05:01, 5 March 2010 (UTC)

Wikipedia did! It doesn't say anything about Wikipedia being accurate, though... --Tango (talk) 05:39, 5 March 2010 (UTC)

What about a barking cough? —Preceding unsigned comment added by 79.68.242.68 (talk) 00:48, 5 March 2010 (UTC)

A few come to mind:

• Capnocytophaga canimorsus (one of my favorite bacterial names)
• Pasteurellosis (esp Pasteurella multocida, another great name)
• Ringworm (e.g. Microsporum canis)
• Toxocariasis (esp Toxocara canis as a cause of visceral or ocular larva migrans)
• Cutaneous larva migrans

I'm sure there are others. -- Scray (talk) 06:13, 5 March 2010 (UTC)

There is at least one other, mange. Dismas|^(talk) 16:23, 5 March 2010 (UTC)

Queen bee naughty bits

Resolved

I can't seem to find a good diagram of queen honey bee anatomy to answer this question for myself. Apparently the stinger in most stinging insects is a modified ovipositor. A queen bee has a stinger, and she posits ova (I don't know if she has an ovipositor as such), so how does that work? Thanks. --Sean 22:12, 4 March 2010 (UTC)

It does seem odd and I can't find an explanation. Our article, Bee sting says: "In worker bees, the sting is a modified ovipositor. The queen bee has a smooth sting and can, if need be, sting skin-bearing creatures multiple times, but the queen does not leave the hive under normal conditions." This seems to confirm your statement, but does not really explain it. --Tango (talk) 05:12, 5 March 2010 (UTC)

Why can't it do double duty ? That is, deliver poison, when needed, and eggs when needed. The urethra in mammal males does double duty and the cloaca of many birds, reptiles, etc., does triple duty or more. StuRat (talk) 12:41, 5 March 2010 (UTC)

Perhaps it does, but the sizes seem wrong. A honeybee egg looks like a 1/2 scale grain of rice, and all the stingers I've ever seen are tiny in diameter, like a stout dog hair. I'm going to try a more specialized forum and will report back here. --Sean 13:57, 5 March 2010 (UTC)

I bet a queen bee's stinger is significantly larger, and probably also stretches dramatically when producing young, as a vagina does. StuRat (talk) 14:57, 5 March 2010 (UTC)

Self-answered by following up a ref in Hymenoptera (p. 49 of Introduction to Insect Biology and Diversity): "In the stinging Hymenoptera, the ovipositor no longer functions to deposit eggs; instead, eggs are released from the vaginal opening on the eighth segment." --Sean 21:33, 5 March 2010 (UTC)

Cool. I've put the resolved tag on this Q. StuRat (talk) 13:25, 6 March 2010 (UTC)