I Is the Holographic Principle the Key to Understanding Our Universe?

[craigi]

Can I refer back to what Craigi said that the idea that there is a reality in 2D at the edge of the cosmos is a popularisation of what the Holographic Principle is really all about. Is it an inaccurate simplification of ideas which are beyond most folk's mathematical training ?

I watched a few things by Susskind and his colleagues on this, and to me they seemed to be pretty much saying that (theoretically) this really is a 3D projection from a 2D reality. How far should it be taken as truth or analogy.

The problem with this is that without knowing what it is that is encoded on the boundary it doesn't tell you much. We can encode in any number of dimensions we choose. For example, the computer you're using right now, uses a 1 dimensional memory system, from that you're looking at a 2D image. We can create 3D representations with it and so on.

If you want to make genuine progress in understanding the Holographic Principle, the question you need to be asking is what it is which is encoded on the boundary.

I also want to re-iterate that it makes little sense to talk of the lower dimensional representation as more real than your familiar instinctive human representation of the world.

Also, in holography there is a light source, it only works with a laser beam. Is there an equivalent light source in the holographic principle ?

No. There is no analogue of the light source in the Holographic Principle. The term Holographic simply refers to a higher dimensional representation stored on a lower dimensional surface.

If the analogy was a really close one then shouldn't there be a source of energy beyond the edge of the cosmos which animates the hologram ? How far should we take the analogy with a mundane hologram.

This has no meaning in the Holographic Principle.

 

[phinds]

For example, the computer you're using right now, uses a 1 dimensional memory system ...

? How do you arrive at that conclusion? Do you understand the addressing schemes used in computers?

 

[craigi]

? How do you arrive at that conclusion? Do you understand the addressing schemes used in computers?

Yup.

 

[phinds]

Yup.

Yup, what ?? I asked how you arrived at the conclusion.

 

[craigi]

Yup, what ?? I asked how you arrived at the conclusion.

It is typical in a computer system for each memory address to be assigned a unique integer from a set of contiguous numbers, in essence a one dimensional array.

I'm not sure where you're going with this, but I don't really want to go into memory banks, video memory, virtual addressing, memory mapping, indirect jump vectors, multi-dimensional arrays, etc. because I don't think it's helpful to the discussion at hand.

 

[phinds]

I simply meant that the memory is NOT 1D as you stated. It is 2D and I wondered how you concluded that it is 1D. when you say it is a 1D array, what you are completely ignoring is that it is a 1D array of strings of binary digits, which means it is actually a 2D array.

 

[craigi]

I simply meant that the memory is NOT 1D as you stated. It is 2D and I wondered how you concluded that it is 1D. when you say it is a 1D array, what you are completely ignoring is that it is a 1D array of strings of binary digits, which means it is actually a 2D array.

In this sense, I would say that it can be seen as either 1D, as I described, 2D as you describe, or even higher dimensional when we take into account memory banking etc. Which can be a useful example of the point I was making. We can represent information in any number of dimensions which we choose and the key to understanding the Holographic Principle is to understand what it is that is encoded on the lower dimensional surface.

 

[Krill]

Re: computer thing. Computers are objects, their memory hardware is built in 3D. You may be able to argue that the electrons used in the memory are point particles. Maybe it is too much of an abstraction to say that memory and monitors work in less than 3D. Or maybe you mean that the binary 0 or 1 is a dimension, but not a physical one - dimension in a broader sense ?
But taking that to holographic principle, how would information be held in 2D on the surface of a volume ? That is, would it be in some abstract informational form that is perfectly and truly 2D ? Or would it be in matter, which is really 3D ?
For example in Susskind's black hole, anything that fell into the black hole can be represented in the configuration of energy or matter on it's event horizon ?
I got to admit that I get confused about what people mean by 1D and 2D in the real world, given that these are mathematical abstractions applied to things which have 3 dimensions.
What does the information theory say, can information really have 2 dimensions ? Maybe that's another discussion for another thread.

 

[craigi]

Re: computer thing. Computers are objects, their memory hardware is built in 3D. You may be able to argue that the electrons used in the memory are point particles. Maybe it is too much of an abstraction to say that memory and monitors work in less than 3D. Or maybe you mean that the binary 0 or 1 is a dimension, but not a physical one - dimension in a broader sense ?

Not quite. The bit is a unit of information. A bit is stored in a physical form in the familiar 3 spatial dimensions. Within computer hardware and software, each group of 8 bits, a byte, is referenced in an abstract 1 dimensional form. Any section of that same memory can also be referenced in 2 dimensions, or in any number of dimensions which the programmer chooses.

But taking that to holographic principle, how would information be held in 2D on the surface of a volume ? That is, would it be in some abstract informational form that is perfectly and truly 2D ? Or would it be in matter, which is really 3D ?
For example in Susskind's black hole, anything that fell into the black hole can be represented in the configuration of energy or matter on it's event horizon ?

Yes. The information is encoded in an abstract mathematical form.

The only way we can access information in the physical world is through a collection of particle interactions which take place in the familiar 3 spatial dimensions.

I got to admit that I get confused about what people mean by 1D and 2D in the real world, given that these are mathematical abstractions applied to things which have 3 dimensions.

When we talk of 2D it might be a mathematical abstraction or it might be a 2D projection within the familiar 3 spatial dimensions.

What does the information theory say, can information really have 2 dimensions ?

Yes. We can represent information in however many dimensions we like, but again this is a mathematical abstraction.

 

[Krill]

OK thanks. We can say some things about computer memory using the holographic principle can't we ?
Wikipedia says,

"For a given energy in a given volume, there is an upper limit to the density of information (the Bekenstein bound) about the whereabouts of all the particles which compose matter in that volume, suggesting that matter itself cannot be subdivided infinitely many times and there must be an ultimate level of fundamental particles. As the https://www.physicsforums.com/javascript:void(0) of a particle are the product of all the degrees of freedom of its sub-particles, were a particle to have infinite subdivisions into lower-level particles, the degrees of freedom of the original particle would be infinite, violating the maximal limit of entropy density. The holographic principle thus implies that the subdivisions must stop at some level, and that the fundamental particle is a bit (1 or 0) of information."​

So our adoption of binary in the use of computers is a representation, in a way, of a more fundamental digital nature that matter has.
What does it mean that the fundamental particle is a bit of information ? Does that mean that the matter turns out to not really be matter at it's smallest scale and smallest subdivision, but rather is something abstract - a bit ?
What is it that is being flipped between 1 and 0, or yes and no, at that scale ?

And information is proportional to surface area, an example given is that spheres packed within a larger sphere mean there can be more information stored in the larger sphere. So would that mean that a computer memory of a given volume can store more information if it is compartmentalized into smaller volumes within itself ?

I just read a meditation on holographic theory and computer bits here
https://www.scientificamerican.com/article/information-in-the-holographic-univ/

This seems to me to be saying that any analogue conception of the universe cannot be true,

"Fields, such as the electromagnetic field, vary continuously from point to point, and they thereby describe an infinity of degrees of freedom. Superstring theory also embraces an infinite number of degrees of freedom. Holography restricts the number of degrees of freedom that can be present inside a bounding surface to a finite number; field theory with its infinity cannot be the final story."​

Does this mean we live in a digital universe of points that are either yes or no, that matter or energy cannot simply slide around anywhere but has to have specific locations where it either does or doesn't exist ? Or am I off on my own tangent there ?

thanks

 

[craigi]

So our adoption of binary in the use of computers is a representation, in a way, of a more fundamental digital nature that matter has.
What does it mean that the fundamental particle is a bit of information ? Does that mean that the matter turns out to not really be matter at it's smallest scale and smallest subdivision, but rather is something abstract - a bit ?
What is it that is being flipped between 1 and 0, or yes and no, at that scale ?

This seems to me to be saying that any analogue conception of the universe cannot be true,

Does this mean we live in a digital universe of points that are either yes or no, that matter or energy cannot simply slide around anywhere but has to have specific locations where it either does or doesn't exist ? Or am I off on my own tangent there ?

That's a simple model where a region of space would have a finite maximum information storage capacity, but it doesn't match the physics.