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Spacetime Memory?

  1. Sep 18, 2003 #1
    Stephen Hawking's excellent book, "Universe in a Nutshell", explains holography as a phenomenon of interference of wave patterns. Light from a laser is split into two separate beams, one bounces off the object and gets reflected onto a photo-sensitized plate. The other beam is reflected into a lens and collides with the reflected light of the object. When a laser is shone through the developed plate, a fully three dimensional image of the original object is created.

    According to conventional theories, the surface area of the horizon surrounding a black hole, measures its entropy, where entropy is defined as a measure of the number of internal states that the black hole can be in without looking different to an outside observer, who can only measure mass, rotation and charge. This leads to another theory which states that the maximum entropy of any closed region of space can never exceed one quarter of the area of the circumscribing surface, with the entropy being the measure of the total information contained by the system. So the theorists came to realize that the information associated with all phenomena in the three dimensional world, can be stored on its two dimensional boundary, like a holographic image.

    Since entropy can also be defined as the number of states within a region of space, and the entropy of the universe must always increase, the next logical step is to realize that the spacetime density, i.e. the information encoded within a circumscribed region of space, must be increasing in the thermodynamic direction of time.

    Spacetime = Memory storage?

    A universal computation?

    Intelligent design?
  2. jcsd
  3. Sep 18, 2003 #2
    You can invert the thought process. Shrink the surface area, such as with a collapsing black hole, and the entropy decreases. For example, a new theory to come out is that our universe was created by an explosion inside a black hole. This created a white hole, a hole that ejects or repells things, from which our universe emerged. Such a theory has the advantage of not having to postulate any intelligent design or other unfathomable and unobservable process.

    Likewise, you can also interpret the results as merely showing that entropy and syntropy form a continuum. Like up and down, front and back--entropy and syntropy may simply describe something ultimately unfathomable by science-- the paradox of existence.
  4. Sep 19, 2003 #3
    With answers come questions. With new questions come questions. The question that arises in this has been brought up on PF before. What is information? Even though our language has evolved through time, starting with the early people such as the people in Mesopotamia, to make communication easier and better. It was developed to help us understand and also to preach different ideas and concepts. But now, it seems our language only seems to get in the way of things.
    Paden Roder
  5. Sep 19, 2003 #4
    I think that is the converse, I mean, the information of the universe is decreasing in time. The thermodynamical entropy of the universe is increasing but this only will lately lead to a state of high uniformeness, thus low information. Information entropy of the universe conversely to the thermodynamical, is decreasing in time, because information entropy measure the number of bits needed to describe something, and the universe is expected to be simpler progressively
  6. Sep 20, 2003 #5


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    meteor: I disagree. I consider information as a measure of the amount of data required to accurately describe a situation. Though the system is statistically more uniform, there is overall more disorder and so more information is needed. But this sort of information does not IMHO equate to the information of any purposeful universal computer.
  7. Oct 30, 2003 #6
    spacetime memory

    A recent popular science magazine contains an article related to this very subject. I have forgotten the magazine's name. It is also interesting to note ideas R.B. Fuller expressed regarding tetrahedrons and spheres.
  8. Oct 30, 2003 #7
    This popular science magazine was SCIENTIFIC AMERICAN, August 2003.

    Feature Article
    August 2003 issue


    Information in the Holographic Universe
    Theoretical results about black holes suggest that the universe could be like a gigantic hologram
    By Jacob D. Bekenstein
  9. Oct 30, 2003 #8
    Article You Mentioned


    Scientific American Article mentioned

    I just seen your post now and went and got the link from the other thread. It is very interesting indeed.

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