Wikipedia:Reference desk/Archives/Science/2010 February 6

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February 6[edit]

How prevalent is magical thinking among university graduates of the western world?[edit]

(And how about among the western world's adult, general population?)

One glossary of psychiatric terminology (http://www.abess.com/glossary.html) has the following definition of the term:

Magical thinking A conviction that thinking equates with doing. Occurs in dreams in children, in primitive peoples, and in patients under a variety of conditions. Characterized by lack of realistic relationship between cause and effect.

Children, primitives, patients... Hmm!

I used to think that magical thinking, among adults in the western world, was a rather rarely occuring phenomenon, but now I wonder...

Might it be frighteningly more prevalent?

I have found this:

Periodical: Psychology Today,
Article: "Magical thinking"
By: Matthew Hutson, published on March 01, 2008 ( http://www.psychologytoday.com/node/21263 )

Speaking about 'magical contagion' it says:

[...] In one study, 80 percent of college students said there was at least a 10 percent chance that donning one of Mr.Rogers' sweaters, even without knowing it was his, would endow wearers with some of his "essence" — improve their mood and make them friendlier.[...]

I have also found an article claiming:
"Research shows that the frequency of magical thinking and superstitious behavior increases under conditions of stress."

(Title: "The Effects of Stress and Desire for Control on Superstitious Behavior"
Journal: Personality and Social Psychology Bulletin, Vol. 28, No. 1, 102-108 (2002)
DOI: 10.1177/0146167202281009
http://psp.sagepub.com/cgi/content/abstract/28/1/102 )

I do not have access to more than the abstract of that one, so I have no way of finding out whether it gives any prevalence numbers or whether it says anything at all about university graduates' beliefs.

Personal, subjective, experience, though, shows that EVEN some HIGHLY EDUCATED university graduates sometimes resort to magical practices.

When pressed into a tight corner (figuratively speaking) during a heated argument, where they are fighting and desperately wanting to win an argument, then they will sometimes clearly show this strange belief:

It seems that -- when all the facts, circumstantial evidence and plausible reasoning seems to stack up against them -- then, as a last resort,even some highly educated people will desperately cling to the hope and belief that they can MAKE a statement (claim) of theirs, BECOME TRUE -- just by strongly wanting it to be true and/or by stating (saying) their claim in a sufficiently "strong" and "convincing" manner.

I can imagine that this belief may have originated as a post hoc ergo propter hoc logical deductive fallacy, from situations where they had misunderstood something and then received a stern correction from some authority (parent?), whereupon they (wrongly), maybe unconsciously, perceved that it was reality itself that was changed by the correction, instead of just their personal view of the reality at hand.

Well...
I would really like to have some numbers on the prevalence and frequency of this.
Preferrably with some specific scientific references backing it up.

Could you please help me? —Preceding unsigned comment added by 89.8.105.190 (talk) 05:21, 6 February 2010 (UTC) (Subsequent signature-> Seren-dipper (talk) 01:03, 7 February 2010 (UTC)[reply]


100% of normal adults and children engage in magical thinking. It is how our brains are wired. For many citations of studies in college students that confirm this, see the recent popular book on how badly we intuitively understand probabilities and causation that will probably prevent you from ever asking this question again, see The Drunkard's Walk by Leonard Mlodinow. alteripse (talk) 08:05, 6 February 2010 (UTC)[reply]

Perception is reality. Moreover, a person's attitude is crucial to determining their relationship to something. So having 'magical thoughts' does in fact shape how things work out. So it's not really magical at all. Vranak (talk) 11:37, 6 February 2010 (UTC)[reply]
A lot of otherwise intelligent people still believe in the supernatural (eg religion, God) which is not quite what you asked. 78.146.77.179 (talk) 12:25, 6 February 2010 (UTC)[reply]

Now you have 3 meanings, but the essence of magical thinking is imagining a causal relationship between 2 events that does not exist in any objective, verifiable, predictable, practical sense. To the extent that attitude can positively affect something (like other people's behavior), it no longer fits the definition, so I think Vranek's answer is somewhat off the point. Whether you consider belief in a deity to be an example of "magical thinking" depends entirely on whether you think God exists. Cognitive science shows that the way human brains work is to imagine causal connections between nearly all the combinations of events we experience; the core of scientific thinking is to recognize we are always prone to this and to devise ways to prove or disprove these possible connections. alteripse (talk) 12:53, 6 February 2010 (UTC)[reply]

It's not off the point, because the question itself is based off inaccurate conception of human nature. My answers addresses that mistake rather than try to answer directly, which would be building error upon more error. Vranak (talk) 17:30, 6 February 2010 (UTC)[reply]
Wikipedia has an article Dreamtime which I describe as the magical half-life of some Australian Aborigines . Cuddlyable3 (talk) 13:29, 6 February 2010 (UTC)[reply]
Abstract thinking, intuition, morphic resonance, self-reference, perception, mind-expanding, psi (parapsychology), prayer, metaphysics, oneness and if a tree falls in a forest may be of interest. ~AH1(TCU) 21:42, 7 February 2010 (UTC)[reply]

Clarification of my magical thinking question[edit]

User:Alteripse said:

100% of normal adults and children engage in magical thinking. It is how our brains are wired.[...]

Well, that may certainly be true for decisions and actions affected by "Instinctive drift" and "the Unconscious mind".

Nevertheless, what I gather from conversations with the people I have met, is that a significant proportion (hopefully the majority) of the western world population, will probably consider it to be, maybe a bit amusing, but still a blatant display of outright stupidity when they, for example, see someone who quite seriously, deliberately and consistently uses the magic incantation "Knocking on wood" along with its ritual knocking, because of a feeling or belif that it might just help "a little bit".

(I am not talking about the sporadic knockers who know for sure that the knocking and incantation itself is in vain, but who still does knock, sometimes, because it evokes a comforting memory of their late, kind, grandmother who used to 'knock on wood').

There must surely have been done scientific research (sometime, somewhere ?) focused on the prevalence of this kind of noticeably stupid behaviour!

So, can anyone please help me with some prevalence numbers and/or references?        Seren-dipper (talk) 09:32, 7 February 2010 (UTC)[reply]

Oops! I have to correct myself: To say that magical thinking is: "noticeably stupid" is itself not a very bright thing to do. When scrutinized, magical thinking turns out, on the whole, to be a valuable survival tool. Therefore: "remarkably irrational" makes a much better formulation!
  --Seren-dipper (talk) 21:04, 7 February 2010 (UTC)[reply]

life question[edit]

have scientist been able to create life in lab from non living components? (Dr hursday (talk) 08:48, 6 February 2010 (UTC))[reply]

See synthetic life. --ColinFine (talk) 09:53, 6 February 2010 (UTC)[reply]

hello this is hursday again i read the article but i cannot understand it or at least the part of it being cheap and close but also in the article lead me to belief life has not be created maybe i am not understanding article could you please tell me if life has been created by scientist. thank you (Dr hursday (talk) 10:03, 6 February 2010 (UTC))[reply]

It may depend on your definition of Life. See Miller–Urey experiment and Abiogenesis. Off the top of my head I believe that some amino acids, precursors to 'life' may have been made experimentally. --220.101.28.25 (talk) 10:30, 6 February 2010 (UTC)[reply]

The simple answer to your question is No. No scientist has been able to create a living thing in a laboratory. They are able to construct more and more complicated molecules of living things-- way way past amino acids, but no cells that can respond to environment and reproduce. I did not see anything in the synthetic life article that would suggest it is impossible, just that it has not yet been done. alteripse (talk) 13:03, 6 February 2010 (UTC)[reply]

It is a fertile subject for fiction, fiction and research Cuddlyable3 (talk) 13:20, 6 February 2010 (UTC)[reply]
We are seeing breakthroughs at an amazing rate and while nobody has yet claimed to produce an entire working lifeform - we are really close to seeing that. I give it less than 5 years. Here are some of the announcements that lead me to that conclusion: [1][2][3][4]. This guy [5] claims to have actually managed it (although close reading suggests not)...and this guy [6] is also very close.
There is a measure of disagreement about what constitutes "success" in this field. Someone has already moved a strand of DNA from one species of bacteria to another and had it successfully reproduce. Does that count? We have scientists who have synthesised a copy of the (already known) DNA of a real bacterium from chemical feedstocks and inserted that into a bacterium whose DNA had been destroyed and ended up with a living bacterium. That's synthetic - but it's only an exact copy of an existing living creature made synthetically. There are people who are trying to design a DNA sequence from scratch - but how much of that DNA has to be "designed" by the scientist? Is it OK to steal the design of a gene that makes a protein that allows energy to be extracted from sucrose from a natural lifeform and merely glue those genes together to make an organism? Do you maybe have to design all of the proteins yourself, then design the DNA to create those proteins? Is using DNA at all "cheating" ?
I know where the ball is - but I'm not sure where the goalposts are - which makes it hard to tell whether a goal has been scored or not!
SteveBaker (talk) 18:18, 6 February 2010 (UTC)[reply]

particulate fluidisation[edit]

what are the practical industrial applications of particulate fluidisation ?or how particulate fluidisation is helpful to chemical industries ? —Preceding unsigned comment added by Snair0122 (talkcontribs) 08:49, 6 February 2010 (UTC)[reply]

Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misevaluation, but it is our policy here to not do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn how to solve such problems. Please attempt to solve the problem yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. -Avicennasis @ 10:31, 6 February 2010 (UTC)[reply]
While doing your homework, you might find the article fluidized bed helpful. However, the texts you were given for the course are probably going to be more relevant. 86.179.145.61 (talk) 11:23, 6 February 2010 (UTC)[reply]
The big advantage of fluidization is that it allows the discrete (solid) phase (catalyst and/or reactant) to mix better with the continuous (gas/liquid) phase (reactant(s)), thus increasing the reaction rate. (See Dust explosion for an extreme case of exothermic reaction occurring in an (unintentionally) fluidized state.) This is why all the cat crackers at our refinery are of the fluid-bed type -- we get a faster reaction (and hence better throughput) with the same amount of catalyst! 24.23.197.43 (talk) 04:00, 7 February 2010 (UTC)[reply]

Reptiles, snakes or evnous snakes[edit]

Steebe Backshall's Deadly 60 states the following: Most eople of the UK live their whole lives without ever seeing a reptile in the wild, and are certainly surprised to hear six of them." Are there only six kinds of reptiles in the UK or is said about snakes or vernous sakes? The Hungarian translator of the book. --Ksanyi (talk) 09:57, 6 February 2010 (UTC)[reply]

To the best of my knowledge, the only reptiles in the UK are grass snakes, slow worms and adders, of which only the adder is venomous. I (a 20-year-old who occasionally ventures into open grassy areas, heaths etc) have seen a slow worm and a couple of adders. I'd be surprised if more than half the people in the UK hadn't seen at least one of the three during their lives. Maybe city-dwellers skew things a bit. Brammers (talk) 10:03, 6 February 2010 (UTC)[reply]

Woops! Looks like there are six after all. Brammers (talk) 10:14, 6 February 2010 (UTC)[reply]
It's certainly rare to see those things in the UK. I would be surprised if "most" people never saw any...but they certainly aren't common there. SteveBaker (talk) 02:32, 7 February 2010 (UTC)[reply]
Despite spending long days walking far from habitation in the UK, I've never seen a reptile in the wild, so they must be rare in the areas where I walk (mainly Northern England) I often see wild deer, red squirrels etc. so it can't be because I'm too noisy or unobservant. I haven't any documentary evidence, but it seems quite likely to me that the majority of UK residents never see a reptile in the wild, as claimed, though there are warmer areas of the UK where reptiles are more commonly seen. Dbfirs 22:30, 7 February 2010 (UTC)[reply]

I'd say a significant minority of all people in civilized cities don't see reptiles, or even know what they are. Of all people to know what a bandicoot is, I was with an Australian over the weekend and when I asked him if he has ever heard of it, he replied, "Yeah, that's a little squirrel-like rodent thing." Now if there exists even one Australian who doesn't know what about the indigenous marsupials, it's no wonder that New Yorkers have no idea the difference between reptiles and amphibians. DRosenbach (Talk | Contribs) 00:40, 8 February 2010 (UTC)[reply]

To be fair most of the marsupials here are nocturnal and usually out of sight. I only saw a quoll for the first time in the wild a couple of weeks ago. I'd say most people have seen reptiles in Australia's larger cities. There are plenty of Blue-tongued skinks in gardens (four in my own) as well as lots of smaller species. I saw a number of Australian water dragons in Sydney and Canberra. I've also seen a number of Lace Monitors further away from the cities. Noodle snacks (talk) 10:05, 9 February 2010 (UTC)[reply]
There's a difference between biological knowledge and everyday knowledge/familiarity. I see no reason to believe that the Australian whom DRosenabch talked to didn't know about bandicoots or hadn't seen them. A "squirrel-like rodent thing" is a pretty good intuitive description and suggests that he had seen the animal. From the point of view of biological science, being a rodent and being a marsupial are incompatible; but from the point of view of common wisdom and everyday life, a rodent is just a "mouse-like thingie"; and whether this specific mouse-like thingie has a pouch is pretty unimportant.--91.148.159.4 (talk) 02:37, 10 February 2010 (UTC)[reply]

Where on the r/K selection theory scale do social insects like ants and bees fall?[edit]

Where on the r/K selection theory scale do social insects like ants and bees fall? They seem to exhibit K traits of altruism and social organization, yet investment in offspring is low. It is complicated by the fact that they operate like a superorganism.

Are they primarily on the r or K side of the scale? --Gary123 (talk) 10:05, 6 February 2010 (UTC)[reply]

It certainly depends on which factors you base it on, but both the fact that offspring counts are immense and, as you said, investment in offspring is quite low would imo outweigh the social organization, therefore putting insects on the near r side, certainly not as far as bacteria or, for that matter, flies. NoisyJinx (talk) 13:45, 6 February 2010 (UTC)[reply]
further, there's no real evidence that the social organization in social insects is learned - it seems to be largely genetic. one of the rationalizations to K-selective species is that parents must spend time with each offspring teaching required behaviors. --Ludwigs2 19:58, 6 February 2010 (UTC)[reply]

sleep[edit]

hello this is hursday. it seems to be that an organism going into sleep state is would be heavily selected against by evolution that is animal may be eaten by predator also time spent in sleep is time that could be used gathering food or mating with and yet almost all animals sleep why is this? is there some evolutionary advantage to having sleep? wouldnt a creature without need to sleep have advantages over creature that does need sleep? (Dr hursday (talk) 11:50, 6 February 2010 (UTC))[reply]

You are essentially asking why sleep is necessary and we simply do not know. We know that is seems to be universally necessary among animals, we know some of the beneficial things that happen during sleep, and we know some of the bad things that happen when someone is deprived. See our article on sleep. It seems to be the way living things work. alteripse (talk) 12:58, 6 February 2010 (UTC)[reply]

Unihemispheric slow-wave sleep might be of some interest --Digrpat (talk) 14:30, 6 February 2010 (UTC)[reply]
We don't know why sleep is necessary? It's neccessary because parts of the body, particularly the brain, benefit greatly from being in a regular rest state. It's as straightforward as charging your cell phone battery. If you don't do it, it dies. Vranak (talk) 15:34, 6 February 2010 (UTC)[reply]
I've read that the military has experimented with drugs that keep people alert without sleep without any apparent side effects. 67.243.7.245 (talk) 15:40, 6 February 2010 (UTC)[reply]
Yes,we know that it is necessary, but why did we evolve to require sleep? As the OP states, clearly it'd be better for survival to always be alert, and have the "regeneration" going on constantly in the background. -- Aeluwas (talk) 16:17, 6 February 2010 (UTC)[reply]
Plainly it is not optional. And regeneration cannot occur when your neurons are in use. It's like trying to remodel your kitchen while cooking Christmas dinner. It simply does not work. Vranak (talk) 17:27, 6 February 2010 (UTC)[reply]
I don't think anyone but the OP has suggested that sleep may be optional. What everyone is saying is that although we know it isn't optional, we don't really know why (there are lots of theories sure, but none of them really have the strength of evidence for us to be able to say this is why). Saying 'your brain needs rest' may be a good enough answer for a lay person, but this is the science desk. And we do know why rechargable batteries need to be recharged, so that example doesn't work. The 'remodel your kitchen' doesn't particularly work either, for example I would question whether you really can't remodel your kitchen when it's in use (it may not make sense to do it, but that doesn't mean it's impossible) and in any case the brain isn't a kitchen (many modern file systems can be defragmented while in use fairly well which is likely a far better comparison then a kitchen although also still far from good) and there is the 'half the brain sleep' and lots of other credible things that seem they may work, but all we really know is that they don't seem to because few organisms have them. Nil Einne (talk) 10:36, 7 February 2010 (UTC)[reply]
(after edit conflict) The fact that all animals mammals and birds sleep, even after a long hibernation, suggests a strong evolutionary advantage that outweighs the disadvantages you mention, but we still don't fully understand the processes involved (as Alteripse said above). Evolutionary adaptations include sleeping with only half the brain at any time, and not sleeping during the first month of life (as in killer whales), but these seem to be rare. Some humans need less sleep, and this adaptation has a possible link with a genetic change, BHLHB3, but the rarity of these adaptations suggests that sleep is an essential function in a healthy brain. You might like to read, also, our articles on Sleep (non-human) and Sleep disorder. Dbfirs 14:46, 6 February 2010 (UTC)[reply]
Do you mean to imply that birds are not animals?? Dauto (talk) 15:02, 6 February 2010 (UTC)[reply]
Oops! I thought "mammals and birds" and stupidly wrote "animals". Sorry! I've corrected my error. Dbfirs 23:06, 6 February 2010 (UTC)[reply]
Although sleep clearly has multiple functions, I personally believe that the most compelling explanation is the "synaptic homeostasis" theory that Giulio Tononi has been defending in recent years, in articles such as Tononi G, Cirelli C (February 2006). "Sleep function and synaptic homeostasis" (PDF). Sleep Med Rev. 10 (1): 49–62. doi:10.1016/j.smrv.2005.05.002. PMID 16376591.. Looie496 (talk) 17:38, 6 February 2010 (UTC)[reply]
See sleep deprivation for the effects of a lack of sleep on humans. ~AH1(TCU) 21:38, 7 February 2010 (UTC)[reply]

Less Deep Injuries cause Less Pain?[edit]

Hello I recall being told that A less deep injury whould cause more pain then A deep one, due to there being more nerves at the surface layer then deeper down.

Any info on this being true? 94.172.41.229 (talk) 15:12, 6 February 2010 (UTC)[reply]

Seems unlikely - you have to go through the surface nerves to get to the deeper ones. How would the surface nerves "know" that the wound goes down deeper. The closest this might be to being true is that deep wounds are (in some cases) no more painful than shallow ones...but even that seems unlikely. However, I don't have any solid information - there may be more to this than meets the eye. SteveBaker (talk) 15:40, 6 February 2010 (UTC)[reply]
The more severe burns aren't all that painful (Well, in comparison to one of less severity), but that's because they destroy the nerves. Vimescarrot (talk) 16:15, 6 February 2010 (UTC)[reply]
The paper cut article says that the shallow cuts don't bleed much, so pain receptors are left open to the air where they can continue to cause pain. Some of the references in that article might be worth looking at, especially the first one. Buddy431 (talk) 18:05, 6 February 2010 (UTC)[reply]
Testicular trauma would fit in a different category, I think. ~AH1(TCU) 21:31, 7 February 2010 (UTC)[reply]

Good Book on analog filter design[edit]

I'm studying Digital filter design in DSP now. But most books assume that you know analogue filter design, concept of ripples, polynomials and such. Which is a good book to start on the most basics of analogue filter design starting with polynomials and image impedances and builds upto stuff like butterworth, chebychev response, const-K, m-derived, realisations like foster forms etc? Books on network theory does filter design abruptly just listing the different response standard forms, their properties etc. 59.93.33.156 (talk) 16:19, 6 February 2010 (UTC)[reply]

Another thing is those attenuation(Cosh(xxx)), and phase responses which look nothing like actual responses. 59.93.33.156 (talk) 16:22, 6 February 2010 (UTC)[reply]

The book Active Filter Design by Carson Chen, 1982 Hayden Book Co. Inc. leads one from filter basics up to Butterworth, Chebychev, Bessel (and a little on Elliptic/Cauer) forms. Cuddlyable3 (talk) 01:46, 7 February 2010 (UTC)[reply]
I'm assuming active filter design is not much different except for few amplifiers and principles still apply 59.93.33.177 (talk) 03:51, 7 February 2010 (UTC)[reply]
Yes. I found Chen's little book to be weak on active analog filters despite its title. It's good for the analogue filter basics though. Cuddlyable3 (talk) 20:40, 7 February 2010 (UTC)[reply]

Manufacturing process for Methylene Blue Injection 1%[edit]

Feb 06, 2010

To Whom It May Concern ,

It would be my honor and privilege to know you .

It was great to visit your website and learn much from you .

Would you please teach me the MANUFACTURING PROCESS FOR METHYLENE BLUE INJECTION USP 1% from METHLENE BLUE TRIHYDRATE POWDER ((MW: 373.90, CAS# 7220-79-3)

Dilute Methylene Blue trihydrate with water and mix well.

Assay for solution strength per USP procedures .

How to sterilize ( decomposition temperature ) and pack .

Thank you so much . —Preceding unsigned comment added by Haunguyenmd (talkcontribs) 16:33, 6 February 2010 (UTC)[reply]

Here is a data sheet for Methylene Blue Solution for Injection that may help. Cuddlyable3 (talk) 01:37, 7 February 2010 (UTC)[reply]

light (bis)[edit]

has the speed of light been measured after it has travelled a billion years or do people still take it for granted that einstein was right without checking.i am asking this question has i have been told he lied about lightspeed being constant to make his theory of relativity work even though he knew lightspeed is varied. —Preceding unsigned comment added by 82.22.255.246 (talk) 16:43, 6 February 2010 (UTC)[reply]

Not even a scientist as famous as Einstein is assumed to be right "without checking" - that's just not how science works. In fact, the predictions of Einstein's theory of general relativity have probably been checked more precisely and more thoroughly than almost any other scientific theory - imagine how famous someone would be if they managed to prove that Einstein was wrong ! We can certainly observe light that has been travelling for billions of years - light from the quasar 3C 273, for example, has been travelling for over 2 billion years before it reaches us. There used to be a theory of tired light in the 1930s, but it could not be made to fit all the cosmological observations that we now have from distant galaxies, so its is no longer thought to be correct. Gandalf61 (talk) 17:37, 6 February 2010 (UTC)[reply]
Also, nothing in science is taken for granted. Everything is always under scrutiny, including things most people would take for granted. -- Aeluwas (talk) 19:03, 6 February 2010 (UTC)[reply]

Of course nobody has measured the speed of light as light was travelling a billion years - humans didn't exist a billion years ago. But what can be measured is that the speed of light in a vacuum does not depend on the movement of the observer (that's a key insight that special relativity is based upon). For understanding objects that are far away, we need to make some assumptions (like physical laws are the same everywhere at all times) which should be as simple as possible (see Occam's razor). BTW, the tired light hypothesis mentioned by Gandalf61 is not about the speed but the energy of the light. And by the way, Einstein was wrong about quantum mechanics in assuming that there are hidden variables (see Bell's inequality). Icek (talk) 19:27, 6 February 2010 (UTC)[reply]

Bad answer! Light from an object that's a billion lightyears away that arrives on earth today has been travelling for a billion years. We know a lot about the laws of physics in the time (and distance) of it's source because we can measure spectra from those places and see familiar emission lines in them with exactly the expected redshift. We can look at the rate that distant galaxies rotate and deduce that the laws of gravity haven't changed. There is a lot we can tell...not one of those measurements have indicated that the laws of physics were different when that light was emitted. Measuring its speed produces the same answer as you get from a flashlight that's within a few light-nanoseconds of your detector. There are plenty of astronomical objects that we can collect light from that are a billion lightyears away and I'm sure this experiment has been done many times. Einstein was indeed wrong about quantum mechanics - but he didn't author any widely accepted theories about that. He passionately didn't want it to be true and threw up a large number of really interesting objections that forced proponents of quantum theory to think very hard about what they were saying. Quantum theory might well not be as well accepted as it is now if a mind as sharp as Einsteins hadn't pushed the theory to its limits and yet failed to break it. However, we aren't talking about Quantum theory - this is a matter of relativity theory - and Einstein appears to have been 100% correct about that since there are no experiments that indicate that it is not valid and an enormous number that demonstrate that it is. SteveBaker (talk) 23:27, 6 February 2010 (UTC)[reply]
How can one know exactly the redshift to expect from a source before one measures it? And when are you going to stop posting bad English such as "of it is source"? Cuddlyable3 (talk) 01:30, 7 February 2010 (UTC)[reply]
See Is The Speed of Light Constant? and Have physical constants changed with time? for some information about this. It's not possible to check the speed of light over large distances by dividing distance by time, because we have no independent way of measuring the distances or times involved and because spacetime is curved anyway. What can be checked is that light's speed is independent of frequency over very large distances and times (since there's no apparent "rainbowing" of distant transient light signals) and that the laws of physics are identical, or nearly so, out to the edge of the visible universe and back to shortly after the big bang. Redshifts can be compared with other measured properties as a test of cosmological models in some cases—see cosmic distance ladder. Einstein's 1905 paper on the photoelectric effect (for which he won the Nobel Prize) was one of the most important steps in the development of quantum theory. There was nothing wrong about that. -- BenRG (talk) 08:34, 7 February 2010 (UTC)[reply]


I suggest you ask the person who "told" you that Einstein lied about it for some reliable sources. Exceptional claims require exceptional references. --ColinFine (talk) 11:12, 7 February 2010 (UTC)[reply]
I suspect that the person who told you this was reporting a distorted version of Einstein's problems with the "Cosmological constant" - which he described as "his biggest blunder". His original relativity theory predicted that the universe would either collapse or expand forever. But because (he assumed) the universe could "obviously" not be doing either of those things - he kludged his equations by adding in this constant to make everything come out right. Subsequently, when it was proven that the universe is indeed expanding, it became apparent that he was wrong. So he didn't lie (except, perhaps to himself) but he did kludge an equation rather than more honestly standing by what his theory appeared to be saying. But that was nothing to do with the speed of light so if this is what's behind this story, it's horribly distorted from the truth. SteveBaker (talk) 16:17, 7 February 2010 (UTC)[reply]

Measuring snowfall when there are many drifts[edit]

I'm taking a lunch break from shovelling out of the North American blizzard of 2010. While it's not as bad here in west-central Ohio as it is farther east in the USA, it's still bad, and there are plenty of drifts: part of my lawn has several feet, while I could see the grass in other parts when I got up. In conditions like this, how is it possible to measure snowfall? Is it simply an issue of measuring in many different places and using standard deviation? Nyttend (talk) 18:13, 6 February 2010 (UTC)[reply]

I'd take the average (rather than the standard deviation) and check the results against the ones from the nearest Wx station provided by the National Weather Service. Northwest Pennsylvania got an inch, barely noticeable amongst all the lake-effect ;-) ​​​​​​​​Niagara ​​Don't give up the ship 18:47, 6 February 2010 (UTC)[reply]
What I'm meaning is how the meteorologists measure it, not how I'm supposed to figure out how much I got; sorry for the unclear wording. Nyttend (talk) 19:33, 6 February 2010 (UTC)[reply]
That's pretty much it. Average measurements from different locations and check official results to make sure there isn't a significant amount of error in your results. No high tech or complex methods. There are, however, specially-designed snow gauges that try to minimize blown snow. ​​​​​​​​Niagara ​​Don't give up the ship 19:50, 6 February 2010 (UTC)[reply]
More storms are coming but the Great Lakes region look set to miss the major snowfall. Blame the El Nino, Pacific-North American teleconnection pattern and Arctic oscillation. ~AH1(TCU) 21:26, 7 February 2010 (UTC)[reply]

Camping trailers HVAC energy efficiency[edit]

Group of 40 camping trailers ranging from 12' to 40' camp all summer on a river bank at a club and share the same electric bill. Is it cheaper to leave on the air during the day while we're all out boating or turn off the air and turn it back on in the evenings when we return to the campground? —Preceding unsigned comment added by Qcliffy (talkcontribs) 18:21, 6 February 2010 (UTC)[reply]

That's chiefly a function of how good the insulation in the trailers is. The thing to do is to buy a couple of plugin power meters, and run one trailer with the all-day method and the other with the as-needed method, on the same day. -- Finlay McWalterTalk 20:15, 6 February 2010 (UTC)[reply]
No. No matter how good the insulation, you will need less energy if you switch aircon on and off as needed. It may be less convenient, but energetically there is no question. The speed at which the trailers heat up depends on the difference between inside and outside temperature. So the closer to the outside temperature you get, the slower you heat up. And indeed, given that trailers usually have lousy insulation, I would suspect that they equalize after a few hours, in which case no further heat is gained. Financially, it may depend on wether you pay peak prices or a flat rate, of course. --Stephan Schulz (talk) 20:33, 6 February 2010 (UTC)[reply]
Yep - I agree. The insulation provided in camping trailers is a disaster. There is no doubt about it - you need to turn the A/C off when there is nobody in the trailers. SteveBaker (talk) 23:07, 6 February 2010 (UTC)[reply]
This question comes up so many times - usually in relation to central heating. 78.146.77.179 (talk) 01:08, 7 February 2010 (UTC)[reply]
The situation in a house or other large structure is a little different. A house takes much longer to get back to a comfortable temperature after it's been cooking all day - and with better insulation, there is more justification in leaving the A/C turned on with nobody in the house so you don't have to wait an hour for it to cool when you get home. But with a camping trailer, there is virtually zero thermal inertia and it'll get cool pretty rapidly after you've turned it back on. Combined with the terrible insulation (making it expensive to air condition), there is really no justification for leaving it turned on. It's a more debatable point with a large and well-insulated house. For example, my house has foot-thick concrete walls that act to provide huge thermal inertial - it's also extremely well insulated. That means that it takes a long time to heat up after you turn off the A/C - but once it is hot, it takes a long time to cool down again. Hence, we don't generally turn off the A/C unless we're going to be away for a long time - it's a net win though.
"My house has foot-thick concrete walls". Is it a former missile silo or other military structure? 89.242.43.246 (talk) 13:27, 7 February 2010 (UTC)[reply]
Nope - it's a house I designed myself that is as energy-efficient as I could cost-effectively make it. Actually, I kinda phrased that misleadingly - the walls are indeed a foot thick and they are predominantly made of steel-reinforced concrete but with layers of insulating foam and brick...Brick+Foam+Concrete+Foam+SheetRock = 12 inches total. It was built using Insulated concrete forms. (It's for sale too! Blatant advert is at: http://www.fmbaker.com/). SteveBaker (talk) 16:03, 7 February 2010 (UTC)[reply]
Looks very impressive - it would cost ten times as much in the UK. 89.242.43.246 (talk) 20:59, 7 February 2010 (UTC)[reply]
Yep - the land alone would cost that much - that's one of the reasons we live here. SteveBaker (talk) 13:49, 8 February 2010 (UTC)[reply]

Private non-profit camp grounds shower & toilet facilities EPA[edit]

We have a private campground/club grounds for boating club with about 50 persons spending weekends from June - October. In late October, the camp is shut down for the winter. 1 winter out of 3, the river comes up and covers the campground for several weeks. We have well water (tested OK for consumption) and a septic system that serves our 2 showers and 4 toilets for the 5 months we occupy the camp ground. The EPA says that because the river comes up and covers the campground sometimes, we have to shut down our bath house and collect our grey and black water to dispose of at an approved dump site. Is there a way to build some type of composting toilet system that would serve our group? Can we set up outdoor shower facilities that would drain into our current septic system (put only grey water into the field bed?) or put showers on a base of rock that would allow the shower water to trickle down into the sand below? We don't want to contaminate the Ohio any more than it already is, but we have limited funds. —Preceding unsigned comment added by Qcliffy (talkcontribs) 18:32, 6 February 2010 (UTC)[reply]

Portable toilet? Cuddlyable3 (talk) 01:21, 7 February 2010 (UTC)[reply]

What do astronauts do when there's nothing to fly?[edit]

I was just reading an article at CNN about how NASA's Constellation program will be eliminated in the 2011 budget if it passes. It quotes an expert at MIT who says that the proposal calls into question the career tracks of astronauts.

"The astronauts like to fly and anything that reduces the number of opportunities to go into orbit is going to discourage both current and future astronauts" he said.

"But we've been through dry periods before -- before the shuttle was developed and then after the [Space Shuttle] Challenger accident -- and we lived through it."

What do astronauts do when there's nothing to fly? Training all day? Do they ever get bored? 71.57.126.233 (talk) 20:24, 6 February 2010 (UTC)[reply]

Not being an Astronaut or NASA employee, from what I have read about Astronauts they already spend the majority of their time training. After all there are not that many spaceflights. Basic training is 20 Months. They are already very qualified (Bachelor's Degree +), and experienced, therefore very employable people.
Each mission is different, requiring more very specialised training especially, I imagine for Mission Specialists. EVAs are practiced to a high degree, everything is planned and practiced over and over (that might get boring!)
Commander and Pilots are already highly qualified as pilots and will need to keep their skills, so they will be kept busy doing that. If not they will almost certainly have no trouble being employed outside NASA if they can't wait around for a spaceflight that may not come for years, thought even up to now they wait years to 'fly'. Not the ideal situation as far as skills retention, but nowdays even Astronauts suffer from fiscal probelms like most of us do.--220.101.28.25 (talk) 23:37, 6 February 2010 (UTC)[reply]
Of course the ISS will continue to be manned until at least 2015...so there are still jobs for actual, active Astronauts until then. But the stunning success of recent robotic missions doesn't bode well for their long-term careers. SteveBaker (talk) 15:54, 7 February 2010 (UTC)[reply]
But from 35 flight slots on the space shuttle in 2009, we will only get about 6 slots for the Space station next year. So we should lay-off about 80% of our astronauts! Rmhermen (talk) 20:37, 7 February 2010 (UTC)[reply]