Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
Clearly this is a metaphor for something.

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.

user:
pass:
register,


                                                                               

Hawking Radiation Telescope

Look at anything you want, anywhere, anywhen, in real time
  (+2)
(+2)
  [vote for,
against]

What magic nonsense is this you say?

Well, we all know the two slit experiment, and its more bizarre quantum cousins. As the theory goes, a given particle can be anywhere in the universe, spread across a probability function. That quantum probability, for instance, is what allows black holes to radiate out particles that they couldn't radiate under classical relativity. This effect is known as Hawking Radiation.

Assuming quantum theory bears some relationship to reality, this would mean that if you could build a telescope, or particle detector, that filters out all ambient traffic, and captures ONLY those particles or photons that materialized in a quantum fashion (i.e. not having traveled through every point from A to B), and in a further assumption, that one could know what the A for a given particle was, and filter on such source information as well, one could look at any spot in the spacetime continuum, in real time.

How would one detect particles that have not gone through every point from A to B?

Well, perhaps here we take a lesson from the recent explosion in extra-solar planet detection -- who would have thought, after all, that detecting the wobble of a planet's gravitational pull, or the slight dimming due to a transit, would be possible -- and yet it is.

In a similar way, perhaps one could use a star that is known to be on a given arc "today", but is visible in a different arc since light from it is taking so many light years to arrive here. Looking for its telltale signature photons in areas of the sky which are not aligned to the star might yield the occasional photon that "materialized", rather than traveled the distance.

Clearly this, discerning the data that teleports in rather than travels the distance, is the challenging part of building the device. But perhaps even better techniques based on energy levels or other criteria can be devised.

theircompetitor, Mar 25 2014

Hawking Radiation http://en.wikipedia...i/Hawking_radiation
[theircompetitor, Mar 25 2014]

The McGuire Effect http://m.imdb.com/t...quotes?qt=qt0415353
A classic quantum paradox [8th of 7, Mar 26 2014]

Information not destroyed http://www.ndtv.com...us-scientist-499856
[theircompetitor, Mar 31 2014]

[link]






       I don't know enough to figure out why this is wrong.
MaxwellBuchanan, Mar 25 2014
  

       exactly, that's why I found it so interesting :)
theircompetitor, Mar 25 2014
  

       //How would one detect particles that have not gone through every point from A to B?//   

       You can't. By definition.   

       // Looking for its telltale signature photons in areas of the sky which are not aligned to the star might yield the occasional photon that "materialized", rather than traveled the distance.//   

       You have no way of knowing if that photon is from the star who's current location you are pointing at, or the one next to it, or the one right behind you and three doors to the left. Or, for that matter, spontaneously coming into existence in front of your telescope, with no actual source.   

       //I don't know enough to figure out why this is wrong.//   

       That's never stopped me.
MechE, Mar 25 2014
  

       Expound on "no way", [MechE]. I would acknowledge it is hard :)   

       For instance, the linked article talks about fairly obscure ways to prove that radiation is, or is not, Hawking. That in that case, the photon shows up outside the blackhole, and not inside it, is in itself some sort of evidence that it came from within, no?   

       BTW, if we get some REALLY serious computational power, one could for patterns in the noise. For instance, let's say I wanted to look at a star map as it would look 1,000 years from now -- which I can compute. I then look at only the photons that "validate" that map. Kind of like the bible code of photons.
theircompetitor, Mar 25 2014
  

       Before this gets any further, I'd just like to make the confident assertion that all the relevant issues will be resolved within the next 2-3 annotations.
MaxwellBuchanan, Mar 25 2014
  

       well, I have no expectations, not even for an [ignoble], [MB] :) But I just was struck by the fact that this is a bizarre possibility which I have not heard discussed before
theircompetitor, Mar 25 2014
  

       Because an individual photon is not characteristic of a given star. A spectrum of them is, but if this works at all, you are going to receive photons from indefinitely many stars, with no particular probability advantage that any given photon is from your target star. The fact that your scope is pointed in a certain direction doesn't help, since if the position of photons is truly only determined by probability, then there is essentially the same chance that your scattered photon is coming from a star behind your scope.
MechE, Mar 25 2014
  

       A spectrum would certainly increase computational requirements. But, if one energy level photon would arrive by accident, surely there are cases where N do.   

       But I think the "validating starmap" case is more interesting. You know how the starmap will look like to some excent. Can you in fact find in the noise that same star map.
theircompetitor, Mar 25 2014
  

       //Assuming quantum theory bears some relationship to reality, this would mean that if you could build a telescope, or particle detector, that filters out all ambient traffic, and captures ONLY those particles or photons that materialized in a quantum fashion (i.e. not having traveled through every point from A to B)//   

       Here's where you start to go wonky. Quantum indeterminacy drops off exponentially with distance; it never quite goes to zero, true, but becomes almost absolutely undetectable beyond nanometer scales. On light-year scales? You would have to wait a very, very long time for even a single photon from Alpha Centauri to arrive at your detector through uncertainty as opposed to the normal fashion. I don't have the relevant figures in front of me, but I'd wager that the probability is so low that by the time a single photon jumped the gap to your detector, the Sun would already have expanded to burn it up.
Hive_Mind, Mar 25 2014
  

       //But, if one energy level photon would arrive by accident, surely there are cases where N do.//   

       But it's equally likely that you get N1 photons from star A, N2 photons from star B, N3 photons from star C, and so on and so forth. Without any way of already knowing which photons are from which star, the simple arrival of photons does not provide any information.
MechE, Mar 25 2014
  

       Also, keep in mind that you're not just getting photons from star A that jumped the N-light-year gap - you're also getting a lot more year-old photons from A that traveled a bit and jumped the N-minus-1 light-year gap, and even more two-year- old photons, and even MORE three-year-old photons, and exactly as many that are actually older because they jumped the same distance away from you instead of towards you...   

       It would be absolutely impossible to extract any kind of past star-map from such a "signal".   

       Especially since such a signal would be so utterly miniscule that the far more common picometer- scale quantum jiggling of atoms and electrons in your detector would drown it out entirely.   

       (My phone has an unusual anomaly where blocks of text will vary wildly in size from paragraph to paragraph. It makes the site look like a monochrome rendition of Time Cube. Great to have the site back, though. One of the few sites from my childhood that still maintains activity and community.)
Hive_Mind, Mar 25 2014
  

       [Hive Mind] -- so look, that's all good, and my biggest claim to Physics fame was taking a few classes with Dr. Kaku :)   

       But no doubt we could have had a similar discussion about the transit or wobble planet discovery methods. I understand the haystack is bigger and needle is smaller. Nor am I expecting such a device to be built anytime soon. But I haven't heard yet why it's impossible. Look at the lengths they're going to for discovering WIMPs, not to mention the LHC.
theircompetitor, Mar 25 2014
  

       I'm not quite sure you understand the needle-to- haystack ratio here. This is looking for a needle, in a haystack filled and indeed made out of largely identical needles, and also the haystack dwarfs the Local Group in size relative to a standard needle. And jiggles.
Hive_Mind, Mar 25 2014
  

       I knew someone would bring the Local Group in at some point :)   

       I'll take that and I'll add quantum computing.
theircompetitor, Mar 25 2014
  

       No, because the wobble or transit methods don't require information be transmitted faster than the speed of light.
MechE, Mar 25 2014
  

       as does Hawking Radiation
theircompetitor, Mar 25 2014
  

       One piece of photographic paper (assuming it's still being made), one neutrino detector, one very thick lead box.   

       Put items in box. Leave for some time. Develop film, then presumably by excluding the number of neutrino hits, you now have some idea of how many photons quantumly turned up.   

       I'd suggest running that data through a 3d printer, then doing a rubbing of it and then take it to a science fair and say "Hey everyone, here's my rubbing of the star Arcturus".   

       Well, they might be from Arcturus.
not_morrison_rm, Mar 25 2014
  

       Time viewing eh, does this idea have hair? If it is Hawking radiation and this particle and its pair are created from pure energy why would it contain any previous information?   

       //as does Hawking Radiation//   

       No, it doesn't. Hawking radiation requires (in one interpretation) that an object travels faster than light (but there are multiple other interpretations), it does not require information to travel faster than light. In fact, Hawking's formulation specifically prohibits it.
MechE, Mar 25 2014
  

       Again, unless you can explain how you can tell whether a given photon comes from a particular star, reality is absolutely consistent with that theory.
MechE, Mar 25 2014
  

       Pity in his earlier years he did not change his name to "Penguin" or "Zero Point".
not_morrison_rm, Mar 25 2014
  

       // discerning the data that teleports in rather than travels the distance, is the challenging part of building the device. //   

       Made more difficult by the so-called McGuire Effect … <link>
8th of 7, Mar 26 2014
  

       Ha.   

       I am by no means certain that such photon properties are discernible, but I've only been thinking about it for a few hours, and I'm not a physicist :) The "future starmap" idea is one that has potential. Another idea maybe to look for shifted background radiation (i.e. one that comes from all direction, just as one would expect from the big bang, but clearly took a different amount of time to get here)   

       Just as in the experiments that attempt to verify Hawking radiation itself, there may be a way, it maybe a very difficult way, or nearly an impossible way. But I am not convinced it is impossible.
theircompetitor, Mar 26 2014
  

       Maybe I have a suitable explanation here. First, the particles that appear via Hawking radiation are IDENTICAL to ordinary particles, and this alone will make it difficult to determine their origin.   

       The "quantum foam", or "energy fluctuations in the vacuum", or "virtual particles" of QM consists of ordinary particles popping into existence temporarily, usually in pairs, and vanishing again, also in pairs. When they INITIALLY appear, they can possess any velocity up to nearly light-speed.   

       AT the event horizon of a black hole, the escape velocity is exactly light-speed. JUST outside the event horizon, the escape velocity can be such that a just-popped virtual particle might have enough velocity to escape the gravitational field of the black hole.   

       So, according to Stephen Hawking, one particle of a virtual pair gets swallowed by the black hole, which prevents them from being able to get-back- together to vanish again. The other particle is allowed to become a "real" non-virtual type of particle, as a result, and the energy for its long- term existence is subtracted from the mass of the black hole.   

       This newly-real particle, IF it happens to be travelling in the correct direction, can now escape the gravitational field of the black hole. Otherwise it will eventually be swallowed, too, and the overall mass of the black hole won't be affected (in terms of "before" the pair of virtual particles appeared, and "after" the second gets swallowed).   

       If the newly-real particle actually escapes the black hole, remember it will do so by climbing out of a very deep gravitational field. Its velocity, when it finally gets away, might be only a centimeter per second, or even less. (If the particle was a photon, it will still be traveling at light-speed, but its energy content is going to be sucked super- low. More on this in a bit)   

       Now imagine this black hole being located 100 light-years from Earth. How long is it going to take a non-photon particle to travel here from there, travelling a centimeter per second or less? And how do you expect to identify it from all those other particles speeding along (cosmic rays)? What about interactions of that particle with others, in all the ages of time that will pass as it travels toward us from its origin?   

       So, I have no expectation of being able to detect ordinary-type particles that might escape a black hole. We might be able to detect those super- low-energy photons mentioned above, but I suspect we currently don't have a radio telescope big enough to do that job (not to mention that the Earth's ionosphere tends to reflect low-energy photons; the radio telescope may need to be located off-Earth). This is where my understanding of the overall situation comes up short, not knowing just how low-energy those photons will be.
Vernon, Mar 26 2014
  

       [MechE] duh, the answer is, do it in a very dark room. Use one of the WIMP experiments, see if you get photons over a meaningful exposure time, then see if generated map maids out to anything interesting
theircompetitor, Mar 26 2014
  

       Feel free to try. Please don't apply for any government grants, as I don't want my tax dollars at work on something that doesn't.   

       The entire basis of this idea is that you are tracking photons that "tunneled" from the target star. But, depending on distance, you are equally or more likely to receive photons that "tunneled" from stars that your scope is not pointing at. The important point here is that the vector of "tunneling" is completely separate from the vector of the photon itself. Therefore, you are as likely to receive a tunneled photon from a light bulb behind you as in front of you.
MechE, Mar 26 2014
  

       Aha, so you are worried I might actually get a grant! :)
theircompetitor, Mar 26 2014
  

       Given who's actually on the congressional science committees, yes, I'm worried you might get a grant. I'm also worried that feng shui practitioners, dowsers, and perpetual motion inventors might get a grant. Unfortunately it does not seem to be the case that scientific literacy is a requirement for deciding who gets money.
MechE, Mar 26 2014
  

       [Vernon] My understanding is that there are alternate, mathematically equivalent, explanations for the effect, that aren't based on the "virtual particle" thing, but I'm not clear on them. That's why I haven't resorted to that argument, because I'm not certain enough to discuss it.
MechE, Mar 26 2014
  

       // I'm also worried that feng shui practitioners, dowsers, and perpetual motion inventors might get a grant// Well that's just mighty uncharitable. I'm doing this in the spirit of the HB, and I think it's a somewhat fun proposal that I've never heard before, with obvious issues. You are treating it as a humorless peer reviewer.
theircompetitor, Mar 26 2014
  

       Yes, that's what I do here.   

       I will discuss nonsensical ideas as such without a problem, but a serious idea with a fatal flaw in its physics will get that flaw pointed out.
MechE, Mar 26 2014
  

       //a fatal flaw in it's physics will get that flaw pointed out //   

       What if it has a fatal flaw in it's grammar ... ?
8th of 7, Mar 26 2014
  

       Wasn't this already halfbaked by Douglas Adams, using a small piece of cake as the detector?
afinehowdoyoudo, Mar 26 2014
  

       //What if it has a fatal flaw in it's grammar ...   

       Ahem...possessive apostrophe...
not_morrison_rm, Mar 27 2014
  

       "What if it has a fatal flaw in it"'s grammar looks fine to me, other than the missing punctuation.
Wrongfellow, Mar 31 2014
  

       marked-for-tagline   

       " I don't know enough to figure out why this is wrong "
normzone, Mar 31 2014
  
      
[annotate]
  


 

back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle