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Hawking Radition

  1. Dec 10, 2003 #1
    The following was a post I put on another board , I received no feedback and haven't delved in to the matter since posting (busy season ) . The prerequisites are that , there is a consensus that virtual particle pairs are entangled ( in an appeal to authority, two have assured me they are, in fact my first post here was to ask and I got no responce) and a basic knowledge of Hawking radiation and event horizons. So:

    I have been examining both the cosmological impact and local QM effects of Hawking radiation which has raised two thoughts.

    The first and more ordinary is with the Vaccume/ZP energy generation of particle pairs at the event horizon where one is swallowed and one ejected, the first law is preserved not only locally ( the virtual particle must express it self as a negative mass/energy quanta to balance the sides) , but also globally when the expression of the absorbed particle becomes determinate then both particles are no longer virtual and as the absorbed particles represents a net loss of mass/energy to the singularity, the ejected particles represents a net Gain of mass/energy to the universe. So even the eventual "evaporation" of the singularity will result in a conservation as the lost mass of the singularity is offset by the net gain of mass outside of the event horizon. The quantities are inversely proportional. This would most likely exist on a time scale greater then the predicted lifetime model of the universe for all but compact singularities. This seems to be a simple idea and must have been stated before . ( Hawkings work is hard to find and harder to understand, J.Baez tho has many papers on the matter (HR )but I could not find any particular reference to this point.)

    The second more interesting is that is if the VE/ZPE pairs are entangled and the entangled state holds and does not spontaneously break when the absorbsion/ejection takes place..then that represents information from INSIDE the event horizon which is supposedly inviolable. Again I have seen no declarative account of this violation of understood behavior of a BH.

    Any comments?

    To all: This is a GREAT site for all interested in the physics and math of GR , it is a John Baez site of links including software and tutorials from under to graduate level material and free courses!!.
    http://math.ucr.edu/home/baez/relativity.html
     
  2. jcsd
  3. Dec 10, 2003 #2

    LURCH

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    Howdy Till!

    To respond to your first thought, I do not believe that I have ever heard that stated explicitly, either. However, I think it is implied whenever people refer to Hawking Radiation as "Black Hole Entropy". This phrase recognizes that the entire process is a means by which mass (energy) in a black hole can be taken from its very concentrated state, wherein a large quantity occupies a small volume of space, and distributed out to the universe in general.

    Regarding your second idea, I must admit that I have had the same thought. At the time, I was not thinking of VPP's specifically, but rather a stream of more ordinary entangled particles. Perhaps a beam of electrons run through a splitter, where one of the two resulting beams is fired into a BH, and the other is kept under observation outside the EH. I believe the standard response to this thought-experiment would be the statement that entangled particles cannot transfer any information. It won't even work in normal space, much less the inside of a BH.
     
  4. Dec 10, 2003 #3
    Yes, the accepted interpretation has been the embracing of the second law of (Q)TD but I was interested that the immeadeate ,primary effect would the conservation factor of the first law rather the subsumption of " the system" as an addition to universal entropy.altho that may occur. Another case.... if the particle in question is re-absorbed in a star orbiting the BH which has an accretion disk that feeds the BH , does demonstraight an addition to order or entropy ? ( That question does not belong here. I also hold a more Zen like distinction ( and definition ) of order and entropy then most... which also does not belong here.)

    Your interpretation of entanglement seems in error. The entangled particle pair convey information as to the state of the other particle i.e. spin orentation ect. If P1 is in a box and P2 is in a box, we can ascertain the state of either particle by examining the state of the other. If the entangled state maintains itself after the absorption of P2 past the EH then, that de Facto IS information. The entanglement cannot break or the point is moot. The fact (?) that QE can exist locally also goes against ummm, common wisdom, while some argue against long range QE. That many say QE can occur locally is the basis for my questions, conversely if that doesn't hold then I have exercised my fingers for naught. The punch line is no one knows for sure.
     
  5. Dec 10, 2003 #4

    NateTG

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    First off, it's not necessarily true that the information is transmitted between the electrons. There are models e.g. due to Pitowsky that have hidden variables which contain the information instead.

    Even so, considering the quantities that the electron would be brining into the black hole are spin, linear momentum, mass, and charge - which are all quantities that can be measured externally from the black hole already.

    So, once you've fired your electron/virtual particle into he black hole, you can't get any extra information from the other partner in the pair.
     
  6. Dec 10, 2003 #5
    Sir I fear you misunderstand the context of my quirey. It IS true that information can be had from entangled particles. Your understanding is incorrect, even in relation to common particles in "ordinary" spacetime. The vertual particles that are generated are not just electrons , there are positrons, photons , other derivatives of whole lexicon of quantum VE/ZPE particles , also you raise the "hidden local variables" aspect which is a main point of contention of QM VS "classical" Relitivistic views. Surely that deserves more than a few words of dismissal.

    I don't understand the relevance of your second paragraph. Which happens to be mutually exclusive, ( that's like saying that the results of a train wreak represents the same condition that the train had at the beginning of it's trip) the idea here is to be able to define the condition of a pair entangled particles, One on the outside of the EH , the other on the inside.

    One prerequisite was the understanding of Hawking radiation. That Phenomonon has nothing to do with electron guns or any device conceived by man. It is a spontainious expression of QM probabilities that generates virtual particles, I recommend you read some material on the web.

    I restate that any information that is accessible from the associated PP where both are entangled and their pair go thru separate paths of absorption, the other through expulsion , if entanglement holds, represents a transmission of information, wether it happens for a pico second or for the entire "lifetime" of the absorbed particle until gobbled up by the singularity.

    edit to add:
    The issue of Pitowksy sets is a dodge in relation to our particular question and is in contrast to the application of Bell.
     
    Last edited: Dec 10, 2003
  7. Dec 10, 2003 #6

    NateTG

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    Hawking radiation or entagled pairs -- neither can be used for trans-horizon communication.

    I freely admit that I'm not intimately familar with Hawking radiation (or similar radiation that originates in the ergosphere for 'spinning' black holes), but let's take a look at your thought experiment.

    Now, let's take a look at the properties that these virtual particles can have:
    Spin
    Mass
    Charge
    Linear Momentum

    In addition, these pairs will have net spin zero, net mass zero, net linear momentum zero and net charge zero.

    Now, if you look at the properties that a black hole can have we get:
    Angular Momentum
    Mass
    Charge
    Linear Mometum

    So, let's say one of the virtual particle pairs goes into the black hole, then the Black hole can measurably change in accordance with the particle that went through the event horizon without violating the 'information horizon'.

    Now I may misunderstand the thought experiment, but you propose getting information out of the black hole using entagled pairs, but it is not possible to communicate using entangled pairs. I mentioned Pitowsky primarily as a demonstration that entangled pairs cannot be used to communicate -- even if you claim that non-local interactions occur, the existance of a valid model that does not require it indicates that the so called non-local interaction cannot be used to pass other information.
     
  8. Dec 11, 2003 #7
    You have the idea approximately correct. perhaps we shouldn't use the word communication , rather the word information is more exact a term.

    The idea of QE is with a pair of particles that are entangled thier "state" is linked in a way that we can use measurement of one to determine that characteristics of the other. From my other post:" If P1 is in a box and P2 is in a box, we can ascertain the state of either particle by examining the state of the other. If the entangled state maintains itself after the absorption of P2 past the EH then, that de Facto IS information." In other words if the QE state doesn't break then we can observe the ejected particle and possibly determine the state of the absorbed particle. IF that is true it represents a violation of the inaccessibility of any quantity or quality past the EH.
    The non-locality was in fact predicted by Einsteuin in the EPR paper and demonstrated his claim of the incompleteness of QM and his discomfort with "spooky action at a distance". Rather then arguing causality via EPR, Bell or the newest proposition GHZ to explain the mechanism and limits of locality, I mearly propose to take advantage of a known, demonstrated phenomenon
    Again this issue is one that goes to the heart of the currently irreconcilable differences between QM and Relitivity
     
  9. Dec 11, 2003 #8

    NateTG

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    Perhaps I should change my handle to "Narr" while discussing things with you. :wink:

    The problem is that the the information about the other partner in the entangled pair is already available from the black hole.

    With sufficiently precise measurements you could, for example, measure the change in angular momentum of a black hole that is due to an electron entering it.

    Unless you are predicting a quality that the black hole doesn't already have -- i.e. something other than:
    spin/angular momentum
    mass
    linear mometum
    or charge

    then you're not getting any extra information from the entangled pairs.
     
  10. Dec 11, 2003 #9

    LURCH

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    I'm going to be very scepticle of what you said here, but please don't take it as a personal attack: the fact is that the point you made in the above paragraph is one that I have also reached on my own. However, because it is an idea in which I strongly wish to believe, I am careful to resist believing it too easily.

    I have been assured on numerous occasions and on very good authority that no information can be conveyed through entangled particle pairs.
     
  11. Dec 11, 2003 #10

    selfAdjoint

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    You can't be sure that the measurement you make on one of the particles is a measurement on the entangled state - which would do what you say - or a measurement on the particle after it has fallen out of the state (perhaps due to a previous undetected measurement or to decoherence).

    The only way you could apply sufficient controls to guarantee the kind of outcome specified would be to be in continuous communication between the endpoints, at light speeds, thus violating the FTL capabilities of entanglement.

    You can establish a non-classical correlation between the particles, but that is after the fact and does not specify which particle was measured first.
     
  12. Dec 11, 2003 #11
    Nate (AKA narr)
    O gosh so close , yet so far.

    The quality's you say are measurable in relation to a BH are unfortunately...not, at least not directly.. The qualities we CAN measure are only measurable as a phenomenon of pheripheraly existent factors. I/E the absorbsion of gas in an accretion disk can give information about rotation, the derivative mathematics of the BH radius can give a good idea of mass , charge has not been measured. According to theory no other qualities can be known.

    Your claim that the state of a single particle can be ascertained by measuring the qualities of the BH whereas electron mass = 9.10938188 × 10-31 kilograms and a star say Sol, a small star as things go mass of the sun = 1.98892 × 10^30 kilograms which represents a difference of approx. 60 orders of magnitude or less then difference between 0 and the mass of the entire universe 3 x 10^55 which is 55 orders of magnitude.That's for the sun . The singularity is an abstraction that represents infinite density and zero volume. You cannot seriously believe the claim you make..
    Even if you do and there were such sensitive instrumentalities to measure the , ( I can't find a word to convey the vastness of the difference) effect of 1 particle descending in to the BH , again the information would be derived.
    The case I was proposing was there would be directly measurable qualities in the QE pair with one lost eternally to the singularity and the other acting as a barometer of the inside of the EH.

    Lurch
    By all means be skeptical . I hope you meant that in regards to my thought experiment and not to QE itself, there are many sources on the web that are both cornerstones of accepted theory and some counter-arguments, but the phenomenon is real . The reason I post here is not to convince but to see if the idea holds up to scientific scrutiny. Even a failure represents a triumph. I'm an EE and would have my constructs break in the lab and not in the field.


    edit to add: ahh yes, selfAdjoint Stapp and Bedford gave a proof in 2002 as to the robustness of GHZ's three particle approch, I'm not sure where it stands at this time but as the VE/ZPE vertual pairs are that and not threesomes , I'm not sure of the applicability of this approach except for providing the truth of the QE concept in general.
     
    Last edited: Dec 11, 2003
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