Spacetime Memory: A Key to Understanding the Universe?

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Discussion Overview

The discussion revolves around the concept of spacetime as a potential medium for memory storage and information, particularly in relation to black holes and entropy. Participants explore theories of holography, the nature of information, and the implications of entropy in the universe, touching on both theoretical and conceptual aspects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants describe holography as a phenomenon where information can be stored on a two-dimensional boundary, suggesting that spacetime may function as a memory storage system.
  • Others propose that the entropy of the universe is increasing, which leads to the idea that the information density in spacetime must also increase over time.
  • A contrasting viewpoint suggests that as entropy increases, the information content of the universe may actually decrease, leading to a simpler state over time.
  • One participant raises the question of what constitutes information, noting the evolution of language and its impact on understanding concepts.
  • Another participant mentions a theory that the universe may have originated from an explosion inside a black hole, which could provide an alternative explanation without invoking intelligent design.
  • References to popular science articles, such as one from Scientific American, are made to support the discussion on the holographic nature of the universe.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between entropy and information, with no consensus reached on whether the information content of the universe is increasing or decreasing over time. The nature of information itself is also debated, indicating a lack of agreement on its definition and implications.

Contextual Notes

Limitations include the dependence on various interpretations of entropy and information, as well as unresolved questions regarding the definitions and implications of these concepts in the context of spacetime and black holes.

PFanalog57
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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?
 
Computer science news on Phys.org
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.
 
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
 
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.
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
 
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.
 
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.
 
This popular science magazine was SCIENTIFIC AMERICAN, August 2003.

Feature Article
August 2003 issue

PHYSICS

Information in the Holographic Universe
Theoretical results about black holes suggest that the universe could be like a gigantic hologram
By Jacob D. Bekenstein
 
Article You Mentioned

Laserblue,

https://www.physicsforums.com/showthread.php?s=&goto=lastpost&threadid=7628

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

Sol
 

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