Wikipedia:Reference desk/Archives/Science/2014 July 26

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July 26

quantum immortality

this is what i found in simple english wikipedia, see question below:

Quantum Immortality is an idea in which it is put forward that the consciousness stays alive even though the conscious being dies. For example, someone sets off a bomb beside the victim, that victim survives in an alternate universe by being injured but living, or by the bomb not blowing up. However, in the original universe, the victim "dies" in the blast. The consciousness continues to exist in another, perhaps many alternate universes. This is related to the thought experiment of Schrödinger's cat.

The idea is that if you use a special gun that goes off, something called a quark is spinning one way, but not if it spins the other way. However, the quark somehow manages to spin both ways at once, so the universe splits into two separate possibilities as the person pulls the trigger. In one universe, the person survives, in the other, the person dies. The person themself does not notice anything different.

my question is, is that (bold text) true and what does that mean? Dannis243 (talk) 01:25, 26 July 2014 (UTC)

The entire passage is somewhat confused and not very accurate. The bold text is correct, though: it just means that the person never experiences the outcomes in which he dies. In the few outcomes where he somehow survives, he just experiences a narrow escape, just as in any situation where someone has a close brush with death. --Amble (talk) 01:58, 26 July 2014 (UTC)

I wonder about the same thought experiment done with quantum unconsciousness. The apparatus randomly determines each 10 seconds whether to anaesthetize the experimenter. So in some universe, the events that would render him unconscious never happen, and so he remains awake for the experiment.

What is the difference between someone being rendered unconscious, returning with an at least someone different configuration of nervous system later, and someone who dies, but leaves behind some other member of his species who can then pick up and read about the experiment? Wnt (talk) 02:34, 26 July 2014 (UTC)

This sounds like a variant on the old expression, "Blown to kingdom come." ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:06, 26 July 2014 (UTC)

The idea is that some variations of quantum theory maintain that every possible outcome to every event happens in one or other of an infinity of alternate parallel universes. Since you can't reason about what's going on in universes in which you died, then by analogy with the anthropic principle, "you" must exist in a universe in which you survived. What this is claimed by some to mean is that you will live forever - dodging bullets and surviving catastrophies by increasingly crazy and unlikely means. At first sight, this seems like a good thing - it predicts that you'll live forever. But if it's true, the idea might mean that we're going to find ourselves in a literal living hell. This idea would only mean that you survive to observe the universe in this state - not that you are healthy, happy, comfortable or anything else. So, for example, it seems likely that in this view of the universe, the insane series of coincidences actually FORCE you to survive. You can't die even if you try. However, it doesn't prevent you from going blind, deaf, losing all of your limbs, being in continual agony, having all of your family, all of the rest of humanity dying around you, etc, etc. We'd better hope this isn't true - because it means that every single one of us winds up in their own, individual hell-universe. It quite literally dooms us all to the worst hell imaginable for all eternity!

Fortunately, there are many get-out-clauses that most people who've seriously considered it believe will ensure that it isn't true. SteveBaker (talk) 04:41, 26 July 2014 (UTC)

it calld "the next world" , thanks water nosfim — Preceding unsigned comment added by 192.117.12.48 (talk) 05:05, 26 July 2014 (UTC)

All of this depends on there being a non-zero probability of you surviving. What if the probability really is zero?--92.251.220.98 (talk) 12:37, 26 July 2014 (UTC)

The notion of quantum immortality was developed by among others MIT Professor Max Tegmark whose other achievements include writing a word processor in Z80 machine code and proposing his Mathematical universe hypothesis whose postulate is "all structures that exist mathematically exist also physically". Wikipedia's article is Quantum suicide and immortality. 84.209.89.214 (talk) 13:04, 26 July 2014 (UTC)

The mistake made here is that it assumes that time exists in some objective way which is unlikely to be true (it contradicts most of modern physics). So, while you can write down a wavefunction and consider how it behaves under time evolution, it is wrong to say that just because in a superposition of different outcomes you are not present in some of the states, that you must be in one of the other states where you are present. This is only true of you redefine "you" to limit it to you experiencing one of thse future states, making the statement trivial. However, that's not consistent with how you would want to consider the probability of you experiencing one of the possible states you can be in.

What about quantum insomnia? There is always a probability that I could experience the time that I should be not experience if I would not fall asleep in time. Quantum theory yields a finite amplitude for that, and yet I usually sleep well. The hidden assumption made in quantum immortality predicts that we should all suffer from chronic insomnia.

The correct way to think about these issues is to stop considering time as fundamental, the universe doesn't evolve in time. What we consider to be time evolution is just a mapping from one universe to another that preserves information. All these unverses exist a priori. So, it's not true that the dinosaurs don't exist, that's only true in our universe, just like in some other universe it is the case that we are dead and burried for millions of years. Count Iblis (talk) 18:21, 26 July 2014 (UTC)

A related issue is that we don't know whether our universe is infinite or finite. In any given volume of space, there are only a finite number of arrangements of energy and fundamental particles that are possible. So with literally infinite space, you'd expect to find infinite numbers of copies of the exact same piece of space for any sized volume you happened to choose. That means that there are infinite numbers of large collections of entire galaxies that are utterly identical to ours. So infinite numbers of earths orbiting infinite numbers of suns, with infinite numbers of Steve's typing this same paragraph. Of course, there will also be infinite numbers of earths with copies of me that make a typo in this sintence instead of typing it correctly. This leads to another variation of quantum immortality, which is that in an infinite universe, we all exist in infinite variations - including those variations where we survive every terrible thing that can possibly happen to us. The same anthropic principle says that all of us exist without having died in any of a million possible ways because we are the copies who survived. So "quantum immortality" is very similar to "infinite universe immortality". SteveBaker (talk) 19:34, 26 July 2014 (UTC)

Either the infinite universe thing or split universes seem like they can really get out of hand and make a hash of the laws of nature. I mean, if the universes are infinite I suppose there's a universe where I jumped out the window thinking I could fly. There's a universe where I've done so and think that I am flying by flapping my arms, despite normal gravity. There are an infinite number of universes where I do all this and I have the delusion I've been doing it for hours. And if you take the copies of me from all those universes you can put together a nice motion picture where I am indeed in every stage of the wingbeat, flapping my way around town, with a delusional memory that perfectly matches the preceding frames in the picture you've spliced together. So in what sense is it not occurring as an "actual physical phenomenon"? Wnt (talk) 22:49, 26 July 2014 (UTC)

More than that - there are an infinite number of duplicate Earths where not only does a freak wind gust allow you to fly briefly but there are an infinite number of THOSE Earths where by a truly astounding number of consecutive coincidences, you can actually fly whenever you want to. Infinity is a strange concept! SteveBaker (talk) 00:22, 27 July 2014 (UTC)

Some of these wild hypotheses, invented to support other wild hypotheses, remind me of the logic gyrations astronomers had to go through in order to retain the notion of planets orbiting in crystalline spheres. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:37, 28 July 2014 (UTC)

What is being discussed here, honestly, belongs more to the borderline of a philosophy of quantum mechanics. However, there definitely are a number of weird counterintuitive theories that are built upon other counterinuitive ones - and, perhaps, they will all end up wrong - but, as of now, they are not that way because they fit our views, or because we like them, but because they give the most accurate results. Planets orbiting in crystal was kept around because of tradition and culture, modern physics is not.Phoenixia1177 (talk) 09:06, 31 July 2014 (UTC)

I'm not exactly sure about that, I doubt any branch of a superposition ends with people flying at will, or anything like that - as long as we're sticking with the quantum mechanics notion from manyworlds. Moreover, manyworlds as having some sort of ontological validity is not uncontentious - if you look at the reception section in our article it indicates that some who do accept many-worlds do not accept that the worlds are actually real.Phoenixia1177 (talk) 09:06, 31 July 2014 (UTC)

How Steroids eliminate Fungal infections or Hemorrhoids?

If Steroids help to "Construct" tissues... How is it that they "Eliminate" Fungal infections or Hemorrhoids? --- Such actions sound a bit different for me than "Constructing" tissues\enhancing the Biosynthesis of tissues... Ben-Natan (talk) 15:25, 26 July 2014 (UTC)

The problem is your "if" statement; there are hundreds of varieties of steroid, with a multitude of different actions. For more detailed information about steroids acting as an anti-inflammatory, see Glucocorticoid and Cortisol, among many others. Other kinds of steroids inhibit fungi by inhibiting Lanosterol 14 alpha-demethylase (see here for a list). Matt Deres (talk) 16:02, 26 July 2014 (UTC)

The article Hemorrhoid notes that steroid-containing agents should not be used for more than 14 days, as they may cause thinning of the skin. It is more appropriate to prescribe Non-Steroidal (NSAID) drugs to relieve pain and inflammation. 84.209.89.214 (talk) 23:15, 26 July 2014 (UTC)

In reality steroids do not 'get rid of' haemorrhoids, they reduce the inflammation that is causing the irritation, this may give the impression that they have gone, but the swollen anal veins will still be there. Richard Avery (talk) 10:47, 27 July 2014 (UTC)

What kinetics?

By what a physico-mathematical mean of the kinetics always been different from a physico-mathematical mean of the statics?--Alex Sazonov (talk) 17:57, 26 July 2014 (UTC)

Those are all English words, but I don't understand what you are saying at all. Is there another language you speak as a native tongue? Perhaps you should find a question answering service in your native language? --Jayron32 20:03, 26 July 2014 (UTC)

If you're Russian, as your name suggests, maybe it would be better to post your questions in Russian. I can think of several users here who understand Russian and might be able to translate your questions for us. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:20, 26 July 2014 (UTC)

I think the intended meaning of the question is something like "How does kinetics physically and mathematically differ from statics?" I don't have time right now to tackle providing an answer, though. Red Act (talk) 22:39, 26 July 2014 (UTC)

Well, the simplest way to explain it is that kinetics is the study of things that are moving, while statics is the study of things that are not moving. --Jayron32 23:13, 26 July 2014 (UTC)

Yeah, that basically sums it up in one sentence. There's a slightly more detailed comparison at Analytical dynamics#Relationship to statics, kinetics, and kinematics. Red Act (talk) 02:47, 27 July 2014 (UTC)

It's a spamming troll, its posts on Ruwiki are similar, coherency-wise. It just likes stringing sciencey-sounding words together Asmrulz (talk) 05:02, 27 July 2014 (UTC)

Hmm but they're also targetting the Russian wikipedia? I long suspected this was our Argentinian friend who I suspect can't speak a word of Russian and who's native language is probably either Spanish or English. But may be the troll really is Russian although their real English level is obviously far better than they show here (as I guess is their Russian). Nil Einne (talk) 07:48, 27 July 2014 (UTC)

Dose the mass been move in a static’s?--Alex Sazonov (talk) 05:31, 27 July 2014 (UTC)

Perhaps. Statics deals with objects that are in "static equilibrium", which for sure only includes objects on which there is no net force and no net torque, and therefore no linear or angular acceleration. However, it depends on the author as to whether or not the phrase "static equilibrium" includes objects which are moving at a nonzero constant velocity. Wikipedia articles are inconsistent about this; the Statics article says an object moving at a non-zero constant velocity counts as being in static equilibrium, but the Mechanical equilibrium article says it does not. Of the physics textbooks I have on hand that talk about equilibrium in the context of classical mechanics, one of them defines "static equilibrium" in such a way that it would include non-zero constant velocity objects, and one of them defines just the word "equilibrium" the same way, as does this web page[1]. None of those three sources defines "mechanical equilibrium", or distinguishes between mechanical equilibrium and static equilibrium. Looking online, it looks like in places where "mechanical equilibrium" is also defined, "static equilibrium" is defined such that it only includes objects with zero velocity, but in contexts where "mechanical equilibrium" isn't defined, then "static equilibrium" usually but not always is defined in such a way that it also includes objects with a nonzero constant velocity. It really just depends on the author. Red Act (talk) 07:33, 27 July 2014 (UTC)

Sorry, if the mass been move in a static’s it been a static’s or kinetic's potential? I’m been study in the physics of the USSR which always been a physics of Ideal Cases.--Alex Sazonov (talk) 08:03, 27 July 2014 (UTC)

I been see, that science mind of the kinetics always been in a constant moving in static’s!--Alex Sazonov (talk) 08:52, 27 July 2014 (UTC)

More word salad from a troll. Edison (talk) 16:15, 30 July 2014 (UTC)

You can't conclude that from just the above, because good faith attempts at translating technical sentences can produce results that are just as difficult to understand. To see this, try using Google Translate to translate a technical English question into Russian, and then use Google Translate a second time to translate the resulting Russian back into English. For example, via that process, the sentence "How does kinetics physically and mathematically differ from statics?" gets turned into "The kinetics of physically and mathematically different from static?". That resulting question is about as hard to try to understand correctly as the OP's question. Red Act (talk) 17:05, 30 July 2014 (UTC)

I already had done a similar test. I ran a section on relativity from the Russian Wikipedia through Google translate, and it came out perfectly intelligible. Sazonov's posts are always or almost always a nonsensical hash of scientific words in English, unlike paragraphs from the Russian Wikipedia translated by Google. Edison (talk) 18:47, 31 July 2014 (UTC)

Operations sector

What I the best way for a graduate to get into the operations sector whether in events, travel, leisure, airports industries etc? And does operations involve future planning as well? For example would a job in event operations involve the planning and managing of it too? What about for a fixed building such as an airport, shopping mall or station? Is planning and management also part of operations/operations management or is it separate? — Preceding unsigned comment added by 90.201.185.72 (talk) 23:33, 26 July 2014 (UTC)

Those are all quite different industries, even if they share some skill-sets or similar sounding titles. Operations is a very broad field; it often draws people who have academic backgrounds in mathematics, business, management engineering, engineering management, industrial engineering; or people who are farther along in their careers after starting out with a technical specialty in a specific industry.

If you're totally lost, start with the Occupational Outlook Handbook, a service and publication of the United States Department of Labor. That can help you narrow down the exact kind of occupation you're looking for. For example:

• Operations Research Analyst
• Aerospace Engineering and Operations Technicians
• Industrial Production Manager
• Administrative Service Manager

... and thousands of related types of employment prospects. These types of careers typically imply that you have completed a bachelor's degree and/or additional higher education in a relevant field.

If you're outside the United States, you might find your local government service office helpful. For example, the Career Skills and Training website, produced by the UK government, might also be informative.

Nimur (talk) 23:59, 26 July 2014 (UTC)