Wikipedia:Reference desk/Archives/Science/2011 March 4

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March 4

Refusal to investigate the existance of God.

Billions of dollars are spent to investigate the existance of the God Particle(Higgs boson) but scientists refuse to investigate the existance of God even though millions of people including the Pope,Cardinals,Imams and most polititions have constant contact with Him/Her and would be available to prove it.This would be of great value to world peace to prevent the religious divide facing everyone. John Cowell124.179.205.11 (talk) 00:12, 4 March 2011 (UTC)

The scientific method deliberately excludes religious faith. One cannot investigate the existence of something supported only by faith. Scientific investigation of the existence of God would be no different from investigating the existence of any deity, such as the Invisible Pink Unicorn, the Flying Spaghetti Monster, or any member of the Twelve Olympians in the Greek Pantheon. ~Amatulić (talk) 00:17, 4 March 2011 (UTC)

Pretty much every premise in the OP statement is wrong. Lots of scientists undertake investigation into the existence of God and you are free to undertake or fund any such activity you please. You might want to start with an article like Relationship between religion and science and go from there. Vespine (talk) 00:22, 4 March 2011 (UTC)

The OP should also note that "God Particle" is short for "Goddam Particle" because it is so elusive, but Lederman's publisher would not accept that name for his book. -- 119.31.121.88 (talk) 00:40, 4 March 2011 (UTC)

There have been several experiments to analyse the efficacy of prayer. Praying for someone else, who does not know they are being prayed for, shows no measurable effect. Due to the placebo effect, it is hard to check for an effect when the patient prays for their own recovery. For further reading, see this Google search for "double blind prayer study. CS Miller (talk) 06:36, 4 March 2011 (UTC)

Harvard did a study on cardiac patients, who when told they were being prayed for showed a statistically significant rate of worse outcomes, probably due to stress factors. Imagine Reason (talk) 19:38, 5 March 2011 (UTC)

If anyone really could prove the existance of god(s) to the same standard that is usually expected in science, then scientists would listen. The truth is, they can't. Faith and proof really don't go together. --Tango (talk) 00:23, 4 March 2011 (UTC)

I also disagree with Amatulic. There are many scientists that study this issue, amongst others Victor Stenger and Sam Harris argue that as long as religion makes claims about physical reality, there is no reason why science can not be brought to bear about the validity of those claims. You could argue that a pure definition of religion doesn't make claims about the "natural" world, only the spiritual or supernatural, but no religion fits this description. As soon as the spiritual or supernatural affects or interacts with our physical reality, which in all religions it does, then science can have a valid say. That's one of the reasons we don't like religious questions here, because they are very divisive and tend to degenerate into forum like discussions, which this site is not the place for. Vespine (talk) 00:30, 4 March 2011 (UTC)

Belief in Invisible Pink Unicorns does not cause the slaughter of innocent people.J.Cowell124.179.205.11 (talk) 00:46, 4 March 2011 (UTC)

Show me the Pope, Cardinal, or Imam who would be willing to submit any claims to measurable, scientific existence of God to scrutiny by disinterested, objective, and critical scientists. I have not seen them. Show me the claims they are making that they would allow external, unfettered investigation into. I have not seen them. I think you fundamentally misunderstand the situation if you think that religious leaders are interested in having their claims put to rigorous scientific scrutiny. They are not interested in cowing to scientific authority, much less risking the possibility of being wrong. (And even if you believe that God does exist, and does want to help you, you can still imagine a God that doesn't want his existence objectively proven and would hide it when push came to shove, because that would obviate the need for faith.) --Mr.98 (talk) 00:48, 4 March 2011 (UTC)

BTW it's not just faith that would be obviated (I like that word :). It's also free will. A provably omniscient God would not be compatible with free will. Free will requires a person to at least believe that their actions are their own (it's immaterial if the actions really are or aren't). Ariel. (talk) 01:15, 4 March 2011 (UTC)

While scientists can investigate (and disprove) concrete religious claims, like that the Earth is only a few thousand years old, you can't investigate the existence of God, since God can always "retreat" deeper. If we prove that nothing since the Big Bang requires the existence of God, you could then argue that God caused the BB. If we later prove what caused the BB, then God could be said to have created that, etc. StuRat (talk) 02:37, 4 March 2011 (UTC)

...essentially God of the gaps in a(n) historical rather than deeper-detail perspective. DMacks (talk) 04:45, 4 March 2011 (UTC)

The basis of science is to witness the universe in every form and derive the most accurate acount describing its modus operandi, and use this accumulated knowledge to make accurate deductions and predictions for that which cannot be observed.

Since God is not from within this universe, science cannot test for his exsistance or non-existance, there is no testable premise. All submitted evidense is subject to personal interpretation. Plasmic Physics (talk) 03:08, 4 March 2011 (UTC)

What I imagine the OP is saying is you'd go to someone who supposedly talks to God on a regular basis, like the Pope, and say, "so, Pope. Is there anything we could do that would prove the existence of God? Why don't you ask God about it and come up with something that we can test, e.g., look this direction on this day at this time and you'll see a comet the flies by and says, 'hi guys!'" I mean, if such a thing happened, and you could really be sure that it wasn't some kind of colossal hoax, even atheisty me would find it pretty interesting, maybe even compelling. But nothing like that has ever happened and nothing like that will happen. The Pope would never agree to such a thing. Whether that's because he knows it is probably outside of his ability to provide results, or because, again, those kinds of results would have severely problematic theological implications, or however you want to interpret it, it just isn't ever going to occur. No way, no how. It's not a case that scientists would ignore the Pope — I am sure the Dawkinsy types at the least would be happy to set up monitoring stations on the (highly likely) chance that the Pope would look like a fool in the process. But the Pope would not be foolish enough to partake in such a game, and would have perfectly good theological reasons for not participating. Feel free to insert any other religious figure for "Pope" in this paragraph. Every once in awhile such figures do hazard concrete beliefs about when a miracle will happen (the Earth will end next Thursday, etc.), but so far none of them have panned out. --Mr.98 (talk) 03:13, 4 March 2011 (UTC)

God wouldn't likely agree to it either, since it would defeat the whole faith aspect of God-based religions anyways. Plasmic Physics (talk) 03:21, 4 March 2011 (UTC)

That gives me an idea! Has anyone written a book or movie about a world where God DOES exist and is readily verifiable? Answers devout believer's prayers, punishes the wicked and performs regular miracles for example. Maybe investigating the contrasts between THAT kind of world and the one we live in would be an interesting exercise.. Vespine (talk) 03:42, 4 March 2011 (UTC)

There's a book where the protagonists can travel to all sorts of parallel worlds, and one of the worlds has an "active" God. The main difference is that no one can disbelieve, and that sins are punished instantly. It's not explored much else though. I think it's The Number of the Beast by Robert A. Heinlein, but I'm not certain. Ariel. (talk) 04:00, 4 March 2011 (UTC)

The Number of the Beast (novel) is a direct link to the page on Heinleins' book - 220.101 talk^\Contribs 15:02, 4 March 2011 (UTC)

As far as I know, He only proved himself once before. In the Koran (Wikipedia excerpt), I've read that He lowered a table from the sky with a feast on it. Apparently, He wasn't very happy about having to do it, infact He sounded quite annoyed. Plasmic Physics (talk) 03:29, 4 March 2011 (UTC)

How does Plasmic physics know that God is not from within this universe? J.Cowell05:10, 4 March 2011 (UTC) —Preceding unsigned comment added by 124.179.205.11 (talk)

I don't know how PP knows it, but it seems to me an eternal entity could not be part of a universe (as we know it, according to science's current understanding) that has both a beginning and an end that does not allow for anything to exist outside of it. DMacks (talk) 05:30, 4 March 2011 (UTC)

Wow I so terribly do NOT want to start a debate but since when doesn't it allow for anything to exist "outside" of it? I've never heard that, for all we know, there might be an infinite amount of big bangs creating an infinite amount of universes completely separate to our own, in some other "dimensions" or something. Your view sounds "univercentric" to me ;) ... It might be impossible to know, but that's a log way from saying it is positively "excluded"? Vespine (talk) 05:54, 4 March 2011 (UTC)

The question specifically says "this universe", which I assumed meant the one we inhabit, rather than some other one or a superset/multiverse situation. DMacks (talk) 06:01, 4 March 2011 (UTC)

Our God-Bothering polititians will be most upset if you relegate God to another universe!.J.Cowell06:16, 4 March 2011 (UTC) —Preceding unsigned comment added by 124.179.205.11 (talk)

No, what I meant was, that He exists outside of everything, outside of time, space, reality. By "reality", I mean outside of our perspective. Think of it this way, all of the above is a very complex figment of His imagination. That's what I mean with outside. Plasmic Physics (talk) 06:33, 4 March 2011 (UTC)

Would you care to define in what way(s) that differs from non-existence as seen from an "in universe" POV? Roger (talk) 06:57, 4 March 2011 (UTC)

It is simply a matter of personal preference.

Are we getting of topic? Plasmic Physics (talk) 07:11, 4 March 2011 (UTC)

This whole thread is off topic for this desk and should have been boxed from the start. --Sean 14:30, 4 March 2011 (UTC)

If anyone is interested, in Contact_(novel), there is an excellent chapter where science's stand with respect to religion is explained. ManishEarth^{Talk • Stalk} 15:12, 4 March 2011 (UTC)

Rather surprised that in this supposedly enlightened age there are still those who wish to shut down discussions on the most fundamental of all scientific questions.Shades of Galileo,Scopes and book burning.J.Cowell124.185.229.128 (talk) 00:01, 5 March 2011 (UTC)

No, you miss the point. It is not a scientific question at all. Individual scientists no doubt have their own beliefs one way or the other about God, but science per se is not concerned with the matter. It is a question of personal faith, period. Nobody has ever proven that God exists, or that God doesn't exist - in a way that would satisfy science - and they never will. That's why it's not a relevant topic for the Science reference desk. -- Jack of Oz [your turn] 00:11, 5 March 2011 (UTC)

Im confused. Why does it matter if God exists or not? what will it change? If he does exist then we still wont be able to explain anything, we will still be trying just as hard to figure all this stuff out. Its not like if we prove he exists, he will come out from behind the clouds and say ok you got me here are the answers to all the questions you could ever ask. We will be in the same reality either way. —Preceding unsigned comment added by 98.221.254.154 (talk) 01:18, 5 March 2011 (UTC)

Now what if God was proven to exist? If so the conlusion would generate another question, who created God or where did he come from? Maybe God was created by an ancient story teller with a vivid imagination. Perhaps another supreme being created God. Then theres that fact that he just simply does not exist. In my opinion, searching for the existence of a supreme being is a waste of valuable time. We could be doing things more important for all of our benefits. Instead of just finding some proof to satisfy everyone for a short period of time. I do not mean to offend anyone but this is what I had to say. Matthew Goldsmith 19:23, 8 March 2011 (UTC)

Flower identification

Sitting on a coworker's desk in NE China. The plant is basically a 2 dimensional green hand shape. This flower appeared at the very tip of one of the "fingers". Can anybody tell me what plant this is? purple and white flower It's quite fragrant. The Masked Booby (talk) 01:44, 4 March 2011 (UTC)

Looks to me like Neomarica northiana, part of the Neomarica (Walking Iris) genus. Nanonic (talk) 02:04, 4 March 2011 (UTC)

I believe you've nailed it! Thank you. The Masked Booby (talk) 02:08, 4 March 2011 (UTC)

That's a beautiful picture too. If it's yours, would you upload it to Commons, now that you know the name of the plant? ~Amatulić (talk) 21:17, 4 March 2011 (UTC)

Einstein in the Manhattan Project

Why didn't Einstein get clearance for working in the Manhattan Project? It is true that he was left-leaning, but being the genius that he was, and the Einstein–Szilárd_letter, shouldn't anyone consider him more of an asset than a risk? Quest09 (talk) 01:48, 4 March 2011 (UTC)

By that time physics had moved on well beyond Einstein, who was more of a figurehead than a leading physicist. StuRat (talk) 02:29, 4 March 2011 (UTC)

They approached Einstein very early on with the possibility of getting help from him on the theory of gaseous diffusion. They found him to be kind of useless — the sort of work Einstein did well was fundamental and theoretical. The kind of work that was really required to make an atomic bomb was specific and literal and practical. It was in many respects more of an engineering task than a scientific one, albeit it was an engineering task so bleeding-edge that it required huge teams of scientists to work out the details. He was considered a security liability because of his strong political beliefs, as well. But mostly the people who ran the project couldn't see much use for him. Building a bomb required nuclear physicists, engineers, chemists, metallurgists, etc. It didn't require people who had clever ideas about the structure of space and time. It was really not Einstein's forte.

By contrast, Niels Bohr they did bring into the project, even though he also didn't do much of practical value. (He helped with the theory of the neutron initiator, but that's the only practical problem he was involved in, as far as anyone knows.) Bohr was more of a morale builder than anything else. It's also not the case that Einstein was really "beloved" by that generation of physicist in the way that Bohr was; it's not clear to me he would have helped morale. Einstein was also seen by the quantum theorists as kind of backwards for his long-standing debate with Bohr. He also had essentially no students, so it's not like people looked up to him fondly for that reason, the way that many did with Bohr. --Mr.98 (talk) 02:58, 4 March 2011 (UTC)

(ec) Some searching in Google Books turned up The Einstein File by Fred Jerome, which appears to be well researched and cites primary sources. Chapter 4, "Banned from the Bomb", is all about this question. The short version is that there's not enough evidence to be sure, but the author thinks that it's J. Edgar Hoover's fault. You have to remember that this is a bureaucracy—Roosevelt trusted Einstein, but it wasn't Roosevelt's job to make the decision. Incidentally, Einstein did not request clearance; Roosevelt requested it for 31 scientists including Einstein. I somehow doubt that Einstein would have agreed to work on the Manhattan Project in any case. What StuRat and Mr.98 said is also true (Jerome mentions this as well). -- BenRG (talk) 03:12, 4 March 2011 (UTC)

I'm not sure that FDR really trusted Einstein on that level of things. It's one thing to trust him when he says, "Germany's trying to get us, look into this," and even then, FDR didn't really put a lot of money behind that. That's not the same thing as saying, "please run my bomb project."

If Einstein had really been valuable to the project, they probably could have decided to let him in. They made a lot of security exceptions during the war — Oppenheimer was super lefty, practically Communistic, at points in the 1930s, as all well knew. Arthur Compton was a member of various "fellow traveler" organizations. There are other examples as well. Because these people were actually quite essential to the work, Vannevar Bush and later General Groves were willing to look the other way, so long as close tabs were kept on them. With Einstein, it wasn't worth the risk.

It's worth also qualifying what is meant by "risk" here — it isn't necessarily that he's a spy or a saboteur. It could also just be that he's not good at keeping a secret, which is a less vicious, but equally damning, concern.

It's of note that the period in which Vannevar Bush thought about trying to get in touch with Einstein on this, the Manhattan Project was still in the extremely exploratory stages. Maybe at that stage having someone like Einstein would have been useful. But once you get into 1942 or so, he would not have been useful at all. --Mr.98 (talk) 03:23, 4 March 2011 (UTC)

Einstein made his "practical technologist" bones early on in his career, back in the era when Edison and Tesla were inventing useful things. Didn't he work in a relative's electric motor factory? Didn't he invent some type of refrigerator? And finally, didn't he review myriad patents? He still had the same brain, despite the decades of theoretical physics, and he could have been of great use to the project in many practical areas, let alone theoretical physics. Edison (talk) 04:51, 4 March 2011 (UTC)

Sure, very early on he did that sort of thing, with a previous era's technology. But the guy was practically retired by the time of World War II. He spent his time hanging out on the beach and having coffee with Gödel and fruitlessly trying to come up with the Unified Field Theory. He was out of the game. (Oppenheimer certainly felt that he was, in any case. There is some snarky quote that Oppenheimer gave the magazines just after the war about how Einstein was a signpost of where physics had been, not a sign pointing to where it was going.) You really imagine him going to Los Alamos and breaking a sweat on how to design a diffusion plant, or going to Chicago and engineering the first reactors? If he had been some kind of great organizer, the type of guy who could run a big project, I'd agree with you. But he never really displayed a talent (or interest) for that kind of thing. In his work, the stuff he was great at was coming up with the big, grand theory. He was not great at doing millions of calculations, much less quickly. The kind of work that was required to build the bomb was millions of calculations, not big, grand theories. A few clever ideas, sure. But they had other idea people, once the program really got under way. --Mr.98 (talk) 12:43, 4 March 2011 (UTC)

Were it not for security worries, it would have made sense to use the far from ancient and doddering mind of Einstein in the defeat of the Axis, if he were willing to help. Einstein was only 63 in 1942. Richard Feynman was 68 when he played an important role in the Challenger shuttle disaster investigation, which was in an area of technology he had zero background in. Even if Einstein was squeamish about building bombs to drop on Hitler, there were many areas of war research he could have helped with, just as Thomas Edison worked on acoustic detection antisubmarine apparatus and synthetic phenol in WW1, 1914-1918, from age 67 to 71. At a mundane level, Einstein could have screened patent applications to pick out those which actually were physically practical and which could have use in war equipment or in any area useful to the war effort such as communication, electricity, transportation, food preservation, or refrigeration. Edison (talk) 16:30, 4 March 2011 (UTC)

Well, to me the real question is to ask whether he could have worked on other projects, and why he wasn't used more readily there. There were plenty of projects of far lesser security concern than the bomb — things that were graded only "secret" or "confidential" rather than "top secret." An indeed, Einstein did do some consulting with the Navy. But I just don't seem him packing up and going to a government lab, myself. (And, entirely separately, I would argue that Feynman's background — including his war work! — actually made him much more qualified for a Challenger-like investigation than Einstein would have been. Feynman had lots and lots of practical experience in debugging large systems; that's actually what he did during his work with Oak Ridge during the war on radiation safety, on the possibility of critical masses forming inadvertently, if I recall. I don't see any similar experience on Einstein's resume. Einstein and Feynman were both great theoretical physicists, but they had very different minds. Feynman's strikes me as the far more practically oriented.)

Incidentally, there was, I do recall, a physicist who screened said patent applications for the Office of Scientific Research and Development in the manner that you describe (but we lack an article on him). It probably would have been a job Einstein could have, in fact, done quite well if he had been asked to, and wanted to. --Mr.98 (talk) 16:51, 4 March 2011 (UTC)

Physicists at MIT dropped everything to work on radar(secretly). By contrast, it would have been a morale builder if some aging science superstars such as Einstein were shown in Life magazine in a lab somewhere "doing war research" even if it was not really the forefront. A mathematician or physicist is typically far over the hill in terms of major breakthroughs by his early 60's but they are the bedrock of review panels, with experience and perspective to decide what is promising, and what is a blind alley that has been gone down before. I knew women who drove over an hour each way to work a long shift building artillery shells and airplanes in WW2, and it seems unconscionable to have brilliant physicists "sit the war out" rather than making whatever contribution they were capable of to keep Hitler and Hirohito from dividing up the spoils after defeating the Allies. Edison (talk) 16:59, 4 March 2011 (UTC)

Mm, perhaps, but we're getting a bit far afield, now. We've gone from discussing whether Einstein would have been useful for the Manhattan Project, to whether he would have been useful as a bit of propaganda. If I were a government scientist-administrator like Vannevar Bush (who was on the cover of Time magazine for his war research), I wouldn't necessarily want to give Einstein such a soapbox. Einstein's political views were fairly out of the mainstream for the period (even if most of them are pretty tame by modern standards), and propping up someone as a centerpiece can backfire on you. (Would Einstein have followed the "party line" if it went against his convictions? I'm doubtful.) Anyway, I'm not saying that the past had to happen the way it did, but I do think their decisions were defensible along both practical and scientific grounds. Personally I think Einstein is pretty out of step from the kind of scientist who was really quite useful in World War II. He's not a Bush, Oppenheimer, Compton, Szilard, or a Teller. This in no way should be seen as disparaging of Einstein as a scientist, or as a person. --Mr.98 (talk) 20:24, 4 March 2011 (UTC)

There are women (and men) right now who drive more than an hour each way to work long shifts building artillery shells and airplanes. I don't see how this is relevant. --140.180.5.6 (talk) 17:29, 4 March 2011 (UTC)

Sorry for your lack of comprehension of what I was trying to say. You may be unfamiliar with the fact that people (our moms and grandmothers) abandoned their typical lives during WW2 to devote their full time to the war effort, travelling long distances (probably taking far longer than an hour in many cases) at the wartime 45 mph speedlimit on bald tires to do hazardous unfamiliar work. Einstein was basically left sitting on his butt, maybe scribbling unified field equations that could not work on a blackboard,and did not aid the war effort, if statements above are correct. He might have been able to do more to win the war than "Rosie," my ancestor who worked double shifts making antiaircraft rounds, and once setting one off by accident in the crimper, by working faster than the machine was set up for, while Albert sat on his butt, unused and ignored. A wasted Einstein seems criminal. Maybe he could have worked some double shifts and devised a proximity fuse for artillery shells which was less prone to explode over friendly troops on the way up when it should have exploded over enemy troops on the way down, as Audie Murphy reported in his war memoirs, or maybe he could have devised a magnetometer an airplane could have used to locate enemy subs, as the Japanese devised toward the end of the war, or night vision goggles as the Germans devised toward the end of the war, and saved thousands of Allied lives and shortened the war. Edison (talk) 05:11, 5 March 2011 (UTC)

In my web searches the one thing which people are most eager to credit Einstein for in the second World War is the "Philadelphia Experiment". Now I don't believe the crazy stories about that event, but I think it was typical of the military at that time to try to drown out accurate information with wild disinformation (such as covering up experimental aircraft or surveillance balloons with flying saucer alien stories). I reserve suspicion that even after all this time, there might still be some tech he was really working on, perhaps stealth technology for ships - something basic, e.g. "antisound" for radar, hmmm, or for subs... - which remains sensitive enough that Einstein still hasn't been given his due, except by fringe sources. Wnt (talk) 17:33, 4 March 2011 (UTC)

The problem is that there is literally zero reason to suspect this, other than "it'd be interesting if it were true." --Mr.98 (talk) 20:27, 4 March 2011 (UTC)

Oh, you're absolutely right. But there are many things from that war that remain absolutely secret, and thus many histories that seem a little implausible. Like Glenn T. Seaborg's discovery of so many elements after the war, as opposed to, hypothetically, while trying to build a better neutron initiator. We have to indulge our imaginations now and then in order to avoid believing systematic error is fact. Wnt (talk) 00:23, 5 March 2011 (UTC)

I'm not sure I gather your Seaborg analogy at all — Seaborg discovered all those elements because he had a total monopoly on the tools necessary to discover said elements. There's no real mystery there. It's also not like he wasn't working on the weapons program at the same time — he was, in various capacities. While it's always possible there are secret programs out there that have not yet been discovered, there is really no reason to assume any science fiction. It's also hard to imagine that programs of the scale of what you're describing would have existed with absolutely no evidence having surfaced thus far. --Mr.98 (talk) 02:24, 5 March 2011 (UTC)

We know that Seaborg worked on nuclear initiators.^[1] We know that early nuclear initiators are said to have used polonium-210. The question is only whether some improved formula might have been discovered and kept secret. I don't think it's implausible that something more sophisticated might have been thought up and kept quiet. Seaborg may have had great advantages finding elements after the war, but still, I think his output for that period is regarded as absolutely extraordinary. Yes, I know there's no evidence that he discovered any of those elements during the war; I just don't think that in the absence of evidence we have to assume, confidently, that nothing like that happened, when it seems just as plausible that it could have.

I suppose that what really appeals to me about the notion of Einstein hiding ships somehow is that it is the sort of thing that would have appealed to his pacifist ethics. What better war weapon for him to invent than a way to protect innocent ships from skulking U-boats? Wnt (talk) 01:13, 9 March 2011 (UTC)

Time-travel photography

Suppose one has an opportunity to travel to the past and take photos in, say, ancient Greece or Rome (assuming that his/her activity wouldn't affect the subsequent events). Is there any way to prove that the photos are genuine upon return to our times, making such activity worthy? —Preceding unsigned comment added by 89.76.224.253 (talk) 12:24, 4 March 2011 (UTC)

You could test for evidense of image manipulation eg, CGI Plasmic Physics (talk) 12:37, 4 March 2011 (UTC)

There are ancient structures (such as remains of houses) that have been found and identified, but not yet excavated. You could bring a list of such structures and scratch "89.76.224.253 WAS HERE!" on a few of them (to make sure at least one inscription survives) and take pictures. Sjö (talk) 14:11, 4 March 2011 (UTC)

They don't have to be structures that have yet been found—collecting photographs which successfully and accurately guide new present-day archaeological exploration would be an extremely potent evidence. If our hypothetical scenario allows the photographer to leave physical evidence and objects behind, the science-fiction-story-approved method is to bury a small artefact containing a known quantity of one or more radioisotopes in a suitably sealed, tamper-resistant, temper-evident container. TenOfAllTrades(talk) 14:36, 4 March 2011 (UTC)

BTW. Even if time-travel is impossible, can information be transmitted from one time to another? 212.169.188.228 (talk) 14:48, 4 March 2011 (UTC)

Sure, but only in one direction — past to future. Transmitting information from the future to the past is time-travel, just dressed up in different lingo ("information" must be transmitted by a carrier, and the carrier is a "thing" you are sending back in time). --Mr.98 (talk) 14:58, 4 March 2011 (UTC)

I'm not sure why it's so frequently stated on the science ref desk that backwards time travel is impossible. That's not what it says in the article. In answer to the question, I suspect the kind of physicists who think about time travel would make little distinction between information and matter, and tend to regard one as equivalent to the other, but IANAP. 213.122.8.112 (talk) 15:15, 4 March 2011 (UTC)

Photographing the stars will set the time period when you are talking about going back hundreds of years. Of course, any photo of anything is easy to fake now - and will surely be easier to fake in the distant future when time travel might become possible. -- kainaw™ 14:49, 4 March 2011 (UTC)

If some laaarge planet was made of, say, highly shiny metal, and you had an amazing telescope, you could use the reflection to photograph Earth (and possibly its inhabitants) a few million years ago. Finding such planets that show you the past ten thousand years are a bit hard though... Anyways, as of now, we can't even see planets, much less view your reflection on them.

Information can only be transferred forward in time. There are two ways of transferring information, one is with materials (a gold plaque, light, radio waves, paper, etc), and another is with quantum mechanics. Materials can't be sent back in time (because time machines destroy themselves 10^-43 seconds after they are created), and with quantum mechanics, though it can send data faster than light, you can't create a Tachyonic antitelephone with it, for various reasons. If you want some links for more information on sending information into the past, see: Tachyonic antitelephone, and Causality (physics). ManishEarth^{Talk • Stalk} 15:06, 4 March 2011 (UTC)

There are a number of fiction stories with plots very similar to this. Hero gets some sort of past viewer, takes some photographs, then can't sell them because his photographs contradict in some ways with modern archeological thought. Therefore everyone assumes they're expertly made, but poorly researched fakes.

I think your best bet would be to use your past-viewer to identify some archeological sites that have not yet been discovered, then very publicly predict where they will be. (So that, after the fact, there can be no doubt that you were the first to suggest their existence.) APL (talk) 15:54, 4 March 2011 (UTC)

... and here's one of me with a dodo. Tasted a bit like chicken ... Gandalf61 (talk) 16:37, 4 March 2011 (UTC)

Two ideas: (a) Photograph a familiar large natural object (I'm thinking about a mountain) that existed both then and now, and which has been changed by human development, preferably a thousand years ago, perhaps via a strip mine, something like mountaintop removal mining, or a lot of housing construction; (b) Take pictures of the night sky through a telescope (no light pollution!) and when you come back, have an astronomer friend verify that the different star and planet positions align with the date that you were visiting. For bonus points, take a look at list of novae before you go, and make sure to photograph areas of the sky that contain those stars. Neither of these ideas will provide irrefutable evidence that you did travel back in time, but you may be able to convince some Experts, on the grounds that a layman would not really be able to simulate those particular photos. While you're at it please bring back a photo of The Sphinx with its nose; I remain curious. Comet Tuttle (talk) 18:43, 4 March 2011 (UTC)

Naturally, but I presume that proving the portraits of people is impossible... —Preceding unsigned comment added by 89.76.224.253 (talk) 21:48, 4 March 2011 (UTC)

Would that be the sphinx in ancient Greece or Rome? Cuddlyable3 (talk) 05:43, 6 March 2011 (UTC)

Check this spin out. "ancient ... Rome" was an example the original poster gave of a target time. As you can see from our article Ancient Rome, this is a reference to the entire Roman civilization back then, not just the city of Rome; and for several hundred years, Ancient Rome included Egyptian territory including the Great Sphinx of Giza, which I had linked to. So, I choose "Ancient Rome". Saved! Comet Tuttle (talk) 19:14, 8 March 2011 (UTC)

Deepwater Horizon oil spill: Why the glacially slow testing of the blowout preventer?

The Deepwater Horizon oil spill article says that the blowout preventer, which failed to seal the pipe, was removed for analysis on September 4 2010, that the investigation by NASA began November 16, 2010, and that it was still ongoing December 23, when the U.S. Chemical Safety Board called for for the investigation to be taken over by others due to a perceived conflict of interest. NASA now been investigating this device (which has no apparent connection to aeronautics or outer space) for 3 1/2 months, with no expected date announced for a final report on how it malfunctioned, other than occasional "leaks" about a dead battery and leaky hydraulics. There is nothing like a deadline to sharpen the focus of an investigative team. When are the investigators expected to issue a report on the blowout preventer? The most recent news stories I found, from January 2011 said a "final report" on the oil spill was issued January 11, without the report on the preventer, which was expected in February 2011. I have seen no press coverage of the preventer analysis final report.Is this one of those cases where they wait until the press has lost interest, or has the government progressed from data collection and analysis to spin doctoring of the language in the findings? Edison (talk) 15:59, 4 March 2011 (UTC)

Here are some possible questions to ask as to why it hasn't already been done.

Should NASA drop everything else and divert their limited resources to this one issue?

Should NASA disrupt its current timetable, (which will have been planned sometime back and have other areas, departments, experts, etc., already committed to the current times and places)?

Should NASA just get on and pull apart the blow-out preventer before they have had time to come up with a comprehensive plan to avoid destroying any evidence due to oversights?

Should NASA just place the blow-out preventer in any of their unused lots and pull it apart there, or should they schedule it to be tested in a suitable or custom built test bed (pressurised tank or what ever) which might enable a better scientific analysis to be carried out -so that with the knowledge gained, the occurrence of future oil-spills at sea can be reduced? --Aspro (talk) 17:04, 4 March 2011 (UTC)

This is just me, but I think the OP was more interested in his other questions: namely, why NASA is investigating this in the first place, even though it has nothing to do with aerospace. --140.180.5.6 (talk) 17:16, 4 March 2011 (UTC)

I have over stated NASA's part in this. It hasn't been sent to NASA for their aerospace know-how, rather their project oversight skills and their ability to provided the basic facilities, site security, etc., were the work can be carried out by whoever is brought in to do it. NASA isn't doing the work themselves no more than they manufature rockets and things--Aspro (talk) 19:56, 4 March 2011 (UTC)

From your comments, it just sounds like NASA is Way Too Busy to do this crucial analysis, which bears on possible dangers lurking in countless other blowout preventers, which might be similarly unable to perform their only known function. Maybe the analysis should have been given to some university, or some other group with no knowledge of petroleum extraction, but with "project oversight skills and their ability to provided the basic facilities, site security, etc." like maybe the Federal Reserve, the FBI, the National Security Agency or the National Bureau of Standards. Edison (talk) 05:00, 5 March 2011 (UTC)

Here a news report on it: [2]:

'"The condition of the BOP, as well as additional unanticipated events, were the reasons for the delay," the joint investigation said in a statement.'

Somebody should have asked what the "unanticipated events" were. Perhaps the press has already lost interest. Some appear to suspect sabotage of the investigation:

'A lawmaker and the Chemical Safety Board have questioned whether the integrity of the BOP testing has been damaged by the involvement of a Transocean employee who served as the subsea supervisor on the rig that was drilling the Macondo well.'

StuRat (talk) 21:57, 4 March 2011 (UTC)

Thanks, Stu, that news report is exactly what I was looking for. Strange how much the phrase "unanticipated events" sounds like someone tap dancing while they whistle "Tea for Two" as they try to think up phrasing to make unacceptable blunders seem like acts of God. Edison (talk) 05:40, 5 March 2011 (UTC)

Edison, you may also be interested in reading the National Academy of Engineering's special committee report, commissioned by the President: Analysis of Causes of the Deepwater Horizon Explosion, Fire, and Oil Spill to Identify Measures to Prevent Similar Accidents in the Future. Interim Report on Causes of the Deepwater Horizon Oil Rig Blowout and Ways to Prevent Such Events is available for free to the public. This was a preliminary investigation; the report was published in November; in addition to preliminary technical analysis, one of the critical items they determined was that a suitable agency does not currently exist to evaluate deepwater drilling safety or to investigate accidents. Several preliminary policy-level suggestions were made. In fact, it was this November report that preceded all of the events (such as NASA involvement)that you are currently expressing frustration with! One of the reasons NASA has been doing technical analysis was its role as an uninvolved Government agency; it was pointed out that the Mineral Management Service, who oversaw deepwater drilling, had serious conflict of interest because the same agency collected revenue and enforced policy (a unique case in the Government - compare the IRS and, say, the FBI). MMS has since seen a major organizational overhaul, by presidential decree; NASA was an "independent" agency who would play the role of unbiased Government advocate; and minimize the risk of any crony-ism or direct conflict of interest. But this is also a reason why technical analysis has been going so slow. The engineering analysis of the accident is confounded by legal-ese, decision-by-committee, and government regulation. I had the (mis)fortune to hear a presentation by the NAE committee right before they released their November report - and what I gathered was that the scientific and technical results must all be revealed very strategically to avoid poisoning any legal process that is currently taking place. (And there is some heavy, multi-billion-dollar litigation taking place amongst all involved parties). Nimur (talk) 13:13, 5 March 2011 (UTC)

Where do very sticky stickers come from?

Someone put up an offensive picture on a utility pole near my home and it can't be peeled off. What to do besides calling the city? 12.199.96.253 (talk) 16:18, 4 March 2011 (UTC)

Is this a "science" question? Bus stop (talk) 16:20, 4 March 2011 (UTC)

At your local hardware store, ask them about solvents that remove stickers. I've a little bottle of very nasty stuff that dissolves basically anything sticky within a few seconds. Not very expensive. Very handy thing to have around in life more generally. I'm sure the stuff is toxic as all get-up, but every once in awhile you actually like to get things clean... --Mr.98 (talk) 16:33, 4 March 2011 (UTC)

Acetone might work. Not good to inhale, or otherwise ingest. Bus stop (talk) 16:37, 4 March 2011 (UTC)

Acetone's pretty darn safe to both inhale and ingest: [3]. Buddy431 (talk) 23:41, 4 March 2011 (UTC)

Look for a liquid called "Goo-Gone" at the hardware store (The dam spam filter prevented a link to a useful article at E-how). It is useful solvent for removing adhesive stickers. You might have better luck with the utility company than the city, since the city does not own the pole, although if the Mayor complained to the utility it might motivate them. Edison (talk) 16:47, 4 March 2011 (UTC)

Would it work on stickers that don't come off? YouTube videos primarily show adhesives being removed, but what if the sticker itself doesn't come off? Imagine Reason (talk) 22:33, 4 March 2011 (UTC)

Just because someone else has interfered with a utility pole, does that remove the duty of another citizen to report you to the authority's for committing further possible damage simply because you can't stop your sensitivities from being activated. Should we be encouraging individuals to take things into their own hands like this by answering such a question? Say the bottle of solvent broke and it ignited, other people could be left without a utility until its fixed. --Aspro (talk) 17:18, 4 March 2011 (UTC)

I'm pretty suspicious of the idea that you could really interfere with the utility pole with some solvent. We're not talking about bathing the pole in gasoline. Topical application. And yes, I think in today's day and age, encouraging people to take a little responsibility for their communities is not a bad thing, assuming it is not a really dangerous or hazardous recommendation. I certainly wouldn't expect MY city council or utilities company to do anything about it, with their track record. If citizens do not take some responsibility for public spaces it quickly becomes a tragedy of the commons situation. --Mr.98 (talk) 18:19, 4 March 2011 (UTC)

I suppose a black felt tip pen is out of the question. Richard Avery (talk) 19:34, 4 March 2011 (UTC)

For some reason my various permanent markers never seem to go really dark when I really need them to. Imagine Reason (talk) 20:53, 4 March 2011 (UTC)

Some other things that might work:

WD-40. Still smelly and messy, but not quite as toxic as acetone. Less likely to damage the paint (if any) on the pole than acetone.

Actually I believe WD-40 is more toxic than acetone. Acetone is not very toxic at all. Ariel. (talk) 22:24, 4 March 2011 (UTC)

Yeah, you can literally drink acetone (not without ill effects, but you aren't likely to die or have any long term impairment). One guy drank 200 mL (about a cup) and turned out fine (eventually) [4].

Peppermint oil (or clove oil, etc.). Smells pleasant and less toxic (although I don't suggest you drink a bottle). Can damage plastics, and might damage some paints. StuRat (talk) 21:30, 4 March 2011 (UTC)

Goo Gone and a scraper (such as a putty knife) should do the job.--Srleffler (talk) 18:16, 5 March 2011 (UTC)

Marshmallows in the microwave

What causes marshmallows to expand in size when microwaved? And why do they collapse when you take them out? Googlemeister (talk) 17:11, 4 March 2011 (UTC)

At a guess, I would say that as their made by having air whipped into them, then it is this air that is expanding!--Aspro (talk) 17:20, 4 March 2011 (UTC)

The air expands when it is heated by the warming marshmallow, the marshmallow cools when it comes out of the microwave and cools the air which shrinks. That combined with the very elastic substance of the marshmallow which allows the air to expand but retains it encapsulated inside the goo.Richard Avery (talk) 19:30, 4 March 2011 (UTC)

Air doesn't expand much when heated, but water expands dramatically when boiled. Since microwave ovens use a frequency designed to preferentially heat water, it may boil while the rest of the marshmallow is still well below the boiling temperature of water. Turning off the oven would allow the water vapor molecules to quickly cool and condense back into liquid water. StuRat (talk) 22:00, 4 March 2011 (UTC)

Ditto. (edit conflict) Plasmic Physics (talk) 22:06, 4 March 2011 (UTC)

Note that it isn't really true microwave ovens use a frequency designed to preferentially heat water. See Microwave oven#Principles. It's just that Dielectric heating works better on water then other substances commonly contained in food. According to the last post here [5], nitrobenzene and chloroform can also be efficiently heated, but most of us don't want either in our food... Nil Einne (talk) 22:44, 4 March 2011 (UTC)

An infestation of ladybugs

Okay, I read Coccinellidae#Infestations. It doesn't really explain what I'm seeing in my condo unit.

Nearly every day for the past year, I find a ladybug in our home, buzzing around our dining room chandelier at dinnertime or just crawling up a wall or window. I dutifully catch it and throw it outside. There certainly was never a "swarm" that flew in, as described in the article. We see just one at a time. We'd notice a swarm because they'd have no place to hide, no air ducts, no plants. I suppose the only inaccessible spaces in our home are the spaces behind the kick panels under our kitchen and bathroom cabinets, but I see no reason why a ladybug would want to go into such dry dusty places.

There are plenty of other bugs outside (flies, mosquitoes, moths, etc.), far more numerous than ladybugs, that could fly in or crawl in when we open the door. But we don't see those, except for an occasional crawler like a spider or silverfish. We just see a ladybug about once a day.

I'm skeptical that every day one ladybug waits outside to seize an opportunity to fly into our door on the brief occasions when it opens. And I'm pretty sure they aren't hitch-hiking in on our clothing. And I'm quite certain that I'm not throwing out the same ladybug every day!

I have wondered if they're breeding in our house, but I've never seen any larvae, and I don't know how they'd survive in our home with no plants and no aphids — unless they're eating dust mites or other critters too small for my vision.

Any thoughts about what might be going on? I don't mind the ladybugs, but I'm curious to know how they get in, when other more numerous bugs don't. ~Amatulić (talk) 21:11, 4 March 2011 (UTC)

How can you be certain they aren't on your clothing when you come home ? Do you fully check yourself in a mirror to be sure you don't have one on your back ? StuRat (talk) 21:17, 4 March 2011 (UTC)

These are persistent creatures, capable of finding small crevices, and they show up in the oddest places - between panes of double pane windows, for example. I have little doubt that they'd be coming in through some crack, but finding it may not be easy! Many references like [6] can be found using "asian ladybug cracks" for search terms. Wnt (talk) 00:16, 5 March 2011 (UTC)

Thanks for the responses.

StuRat: Actually, yes. I take my jacket off and check it. Even if they do come in on my clothing, I seriously doubt that one hitches a ride every day. It isn't the time of year for seeing ladybugs outside either.

Wnt: They may be coming through cracks, but as I said there are other more numerous crawly things around that can fit through cracks also, but don't. And why they seem to trickle in at a rate of one a day mystifies me. I think seeing them between panes of a double pane window may be the result of a larva crawling through a crack in the seal of the window pane and then metamorphosing between the panes, since those are rather flat soft creatures while the mature beetle is round and hard and unlikely to fit. ~Amatulić (talk) 01:22, 5 March 2011 (UTC)

Hello. I manage a hotel, and your very same question was a mystery to me for years. There would alsways be one or two lady bugs randomly crawling around somewhere in our lobby. In my experience to your question, there is, somewhere in your home, an infestatation of lady bugs...you just haven't found it yet. Ours was way up in the outside corner of an air duct in the ceiling. Not inside the duct, but rather in between the metal tubing and the wooden housing. Needless to say, they don't really hurt anything, so aside from fogging your house with professional grade chemicals, a lady bug or two crawling around is not so bad relatively speaking. Maybe you should get a houseplant and give them somewhere to hang out ;) Cheers! -- David Able 04:37, 5 March 2011 (UTC)

Pouring liquids

I'm not sure whether the question was already answered earlier, but anyway. When I start to pour juice for example, the pack shortly afterwards starts to "breathe" and "exhales" some quantities of juice, disrupting the normal flow. Why is that and how to avoid it? —Preceding unsigned comment added by 89.76.224.253 (talk) 21:58, 4 March 2011 (UTC)

It's because you are creating a partial vacuum in the container by removing part of the contents without replacing it. An air hole in the opposite side is a simple cure, allowing air to replace the missing contents. If that's not practical, pour slowly enough that the opening is not entirely blocked with liquid, and air will get sucked back in that way.

If you don't do either, the partial vacuum will build until it sucks the some juice and air back in, possibly going slightly over atmospheric pressure, and will then "spit some back out", to equalize the pressure. StuRat (talk) 22:02, 4 March 2011 (UTC)

To expand on that, making an air hole is very easy. Just get something sharp (knife, scissors, pin, whatever) and make a small hole in the top of the carton away from the opening. You'll find even a very small hole makes a really big difference. --Tango (talk) 23:22, 4 March 2011 (UTC)

Use a Churchkey, a device specifically designed for the job (with cans, anyway). Buddy431 (talk) 18:51, 5 March 2011 (UTC)

Apple pH

What would be the approximate pH of a common-or-garden eating apple? DuncanHill (talk) 23:35, 4 March 2011 (UTC)

Probably about the same as the juice, on the acidic side between 3.5 and 4.0. Not as acidic as citrus. There's a list of pH levels from the USDA for various fruit juices here. ~Amatulić (talk) 01:28, 5 March 2011 (UTC)

Thank you. DuncanHill (talk) 03:48, 5 March 2011 (UTC)