Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Verlinde's paper "On the origin of gravity and the laws of Newton"

  1. May 16, 2014 #1
    Why did Verlinde in his paper suggest that information is a central concept in the emergence of gravity? I mean why information and not something else?
     
  2. jcsd
  3. May 16, 2014 #2

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Do you have a link or source for this paper?
     
  4. May 16, 2014 #3

    George Jones

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    http://arxiv.org/abs/1001.0785

    M. next, please give a link and/or journal reference in the body of your post, not just a paper's title in the subject line of a post.
     
  5. May 17, 2014 #4
    These are two snapshots, one from the abstract and the other from the introduction.
     

    Attached Files:

  6. May 17, 2014 #5

    MTd2

    User Avatar
    Gold Member

  7. May 17, 2014 #6
    I believe the inspiration for it comes from 2 things. Firstly, it is of interest to interpret physical phenomena in terms of information in keeping with the Holographic Principle. Secondly, the equations of gravity have similarities with the equations of thermodynamics.
     
  8. May 17, 2014 #7

    atyy

    User Avatar
    Science Advisor

    Yes, I think those are the ideas. Entropy and information are related, in the sense that entropy is uncertainty, and Shannon's information (1948) is a reduction in uncertainty. Then Jacobson (1995) noticed that Einstein's equations could be derived from thermodynamics.

    There's been progress on this front (related only spiritually to Verlinde's paper, but not formally, I think):

    http://arxiv.org/abs/1308.3716
    Gravitational Dynamics From Entanglement "Thermodynamics"
    Nima Lashkari, Michael B. McDermott, Mark Van Raamsdonk
     
    Last edited: May 17, 2014
  9. May 17, 2014 #8
    Oh okay I see then it was an inspiration that came because all they wanted was related to entropy which is in turn related to information. Thanks :)
     
  10. May 17, 2014 #9

    atyy

    User Avatar
    Science Advisor

    Yes. In the paper by Laskhiri et al that is linked above, they talk about a quantum quantity called the "relative entropy". The related classical quantity is also called the relative entropy or Kullback-Leibler divergence.

    The Shannon mutual information can be written as a sort of Kullback-Leibler divergence as given in http://en.wikipedia.org/wiki/KullbackÔÇôLeibler_divergence (see the section "Relation to other quantities of information theory)."
     
  11. May 17, 2014 #10
  12. May 17, 2014 #11

    MTd2

    User Avatar
    Gold Member

    I just want to know what Verlinde said about Dark Matter and his theory on the conference.
     
  13. May 17, 2014 #12
    He discusses that here:
    http://pirsa.org/11060065/
     
  14. May 17, 2014 #13

    MTd2

    User Avatar
    Gold Member

    I know that one... But after almost 3 years, I just wanted to see something beyond drawings and speculations...
     
  15. May 23, 2014 #14
    Please use the correct last name in the title and the tags.
     
  16. Aug 19, 2014 #15

    tom.stoer

    User Avatar
    Science Advisor

    is this idea taken seriously? or has it been abandoned?
     
  17. Aug 21, 2014 #16
    I recall an interview with Verlinde, where he says that he's trying to develop the idea alone. He draws an analogy with Einstein's work on relativity and is talking about a timescale of decades.
     
  18. Aug 21, 2014 #17

    tom.stoer

    User Avatar
    Science Advisor

    so I'll ask the the admin for a reminder function in the forum software which alerts me in ten years or so ;-)
     
  19. Aug 21, 2014 #18
    I don't know why they would choose to concentrate on area as holding information. Information is obtained from probability distributions. And a distribution is taken with respect to a random variable along an axis, right. In other words, information is obtained with respect to the space of some variable; there's no information without space. So you could have information associated with 1D, 2D, 3D, etc.

    And if there's no information without a space, does that in itself argue for a minimum or maximum amount of information per length and therefore per area and per volume?
     
    Last edited: Aug 21, 2014
  20. Aug 21, 2014 #19

    MTd2

    User Avatar
    Gold Member

    I think Einstein discussed frequently and deeply his works with a lot of people, he was never alone. I guess giving too much money to Erik was not a very good idea.
     
  21. Aug 21, 2014 #20
    The reason area, as opposed to volume, is considered so significant to information content is due to the work of Beckenstein, de Hooft and Susskind.

    Try reading the wikipedia articles on the Beckenstein Bound, the Holographic Principle and AdS/CFT correspondence for a starting point.
     
    Last edited: Aug 21, 2014
  22. Aug 21, 2014 #21

    atyy

    User Avatar
    Science Advisor

    I think the proper implementation of the spirit of these ideas involving gravity and thermodynamics, actually Jacobson's idea is:

    http://arxiv.org/abs/1308.3716
    Gravitational Dynamics From Entanglement "Thermodynamics"

    http://arxiv.org/abs/1312.7856
    "Entanglement entropy obeys a 'first law', an exact quantum generalization of the ordinary first law of thermodynamics."
     
  23. Aug 21, 2014 #22
    Thank you. But what seems unaccounted for is that you could place masses in two different places with surfaces constructed for information purposes, those two surfaces could intersect in a perpendicular manner at a particular point. Then that would mean that information has a 3D character, not just 2D for one surface.
     
    Last edited: Aug 21, 2014
  24. Aug 21, 2014 #23

    atyy

    User Avatar
    Science Advisor

    marcus posted this paper in the CMT/area laws/LQG thread, which also seems relevant to the relationship between the first law of thermodynamics and gravity:

    http://arxiv.org/abs/1408.3705
    Deriving the First Law of Black Hole Thermodynamics without Entanglement
    William R. Kelly
     
  25. Aug 22, 2014 #24
    One thing I like about Verlinde's paper is his statement, "One could assume that information is stored in points of a discretized space". So if space is like memory that stores information, then there is entropy associated with erasing memory. Then if a wave disturbance should travel by, it first puts information in that storage place and then erases it as it leaves. So does the speed of light by itself indicate a maximum rate of entropy change?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook