Bekenstein bound Puns

I hope this question is appropriate for this sub (and I apologize for my english).

I have a doubt regarding the physical interpretation of the bekenstein bound (and of the black hole entropy). It is often portrait as to imply that the number of microstates inside a volume is bounded by the enclosing area (which hints that gravity is "holographic" in some sense).

However, studying entanglement entropy, area laws are ubiquitous. This makes sense, as the entanglement entropy (if I understood correctly) measures only those microstates which are entangled across the boundary (am I wrong on this understanding?). And in the past it has been proposed that the Bekenstein Hawking entropy is the entanglement entropy at the event horizon, which would explain the area scaling. But it seems to me that this would imply that the bekenstein hawking entropy does not measure the internal microstates but only those entangled across the event horizon (I think that prof. Ted Jacobson is of the same opinion).

Moreover, we have a proper demonstration of the Bekenstein bound in qft, due to Casini (2008). However in this demonstration the entropy appearing in the bound is exactly the entanglement one.

All of this seems to suggest to me that the bound is not on the total number of microstates inside a volume as it is often portrait, but "only" on those that are correlated at the boundary (and therefore is not that surprising that it scales like the area).

Where am I mistaken in my understanding? Have i misunderstood entanglement entropy?

The Bekenstein bound is the maximum amount of information required to perfectly describe a volume of space down to the quantum level. If a region of space exceeds the Bekenstein bound, it becomes a black hole. Counterintuitively, the Bekenstein bound does not scale with the volume of space, but rather the minimum surface area required to enclose a volume of space. This has led some physicists to accept a ‘holographic universe’ theory which states that the universe is actually the 2 dimensional surface of a sphere with 3-dimensional information encoded on this surface.

If we assume that the Bekenstein bound puts similar limitations on the amount of information capable of being stored in n-dimensional volumes, such that an n-dimensional volume can be perfectly described by an n-1 dimensional surface which can enclose the original n-dimensional volume, we can determine how large a proton would be if all its 8 extra dimensions (according to M theory, aka string theory) were unfolded into 2 dimensions.

The size of the extra dimensions in string theory is a subject of debate. These may range from the Planck scale (much smaller than a proton) to 44 micrometers (much larger than a proton). For now, I will assume that a proton's ‘lengths’ along the other dimensions are the same as its radius. After all, its radius is the same in all 3 spatial dimensions, so it could be the same in the 7 extra dimensions string theory provides. I will also assume a proton is a 10-dimensional sphere (M theory uses 11 dimensions, 1 of time, 10 of space).

The n-1 dimensional surface area of an n-dimensional sphere is given by the following equation:

https://preview.redd.it/wpdps35wtn181.png?width=85&format=png&auto=webp&s=62b8c8d67a01871d930addf518b5515187dd88c6

A proton has a radius of 855 attometers. The following table starts with the 10-dimensional volume of a proton with this radius and determines the minimum (n-1)-dimensional surface area required to describe that volume in the lower dimension.

https://preview.redd.it/gk4pm9q1un181.png?width=719&format=png&auto=webp&s=b48a0e0ae4d0c1af51732a1d5ecc77a5880db5be

1,011,250,285.6924 attometers squared is about 1.567e-24 square inches. If this area was in the shape of a square, it would be 31800.1617 by 31800.1617 attometers, so about 37 protons by 37 protons, much smaller than an atom, and

According to Wikipedia, the Bekenstein bound says that there is a limit on the amount of information required to describe a system of a given size and with a given amount of energy, and therefore a finite limit on the number of possible states of such a system. However, if physical quantities are real-valued, then it would seem that any system containing such a physical quantity would have infinitely many possible states.

I think there is a problem with this argument, but I do not know what it is.

I am sure many people on this forum know of this "holographic" aspect of physics, but this is for the layperson who is new and has not heard of it:

Basically, the max amount of info you can have in some 3D volume is proportional to its 2D surface area, otherwise that 3D volume will collapse into a singularity, information itself can literally form a black hole.

This has to do with entropy, and that the entropy of a black hole (3D object), is proportional to its surface area. Basically all the information that goes into the black hole must be also contained on the event horizon as a projection for quantum information conservation, which is released back via Hawking radiation.

See 1:18 in the video, or watch the entire thing because its interesting. (And everyone should watch PBS Spacetime)

https://www.youtube.com/watch?v=XxVlGAFX7vA

Paging /u/deej_bng u/cozmo23

I think you guys need to go back and patch this ASAP. With Nolan North's new voice work being introduced it has also brought an egregious mistake in the pronunciation of "Bekenstein". It's pronounced STINE, not STEEN.

Jacob Bekenstein, is the theoretical physicist that formulated the Bekenstein Bound (limit). He also recently passed away (08/16/2015). This NEEDS to be corrected and patched in out of respect for the man and his contribution to science.

https://www.youtube.com/watch?v=beXMrgon4eo

As in mass, charge, and angular momentum.

Are there other quantities which can contribute towards a region of spacetime reaching its Bekenstein bound?

How is the equivalence of information (in bits) to area derived upon? That is, did Bekenstein make some assumption about the information contained in a Planck length or Planck area and extrapolate? How is the equivalence between mass and information arrived upon? What are the assumptions that form the basis of this information to area equivalence?

*I edited this so it would be more sensible, there was some strange bug when I was typing words into the dialogue box, so my question should be more clear now

Hi r/AskPhysics! This might be a weird question, but I’m writing a science-fiction concept album and I want to make sure I get my facts straight. So the premise is that the universe is dissolving because of information overload, so I read about the Bekenstein Bound, meaning there is a limit to entropy or information within a finite region of space. So take the universe, which is, for the sake of simplicity, finite, and more specifically, one random point in time instead of a period. My question is, what happens if you take an object from another point in time and bring it back? Does this mean information is added to the first point, thus exceeding the Bekenstein Bound and resulting in the collapse of the universe? Apologies in advance if I’m misinterpreting certain concepts!

It seems to me that if we extrapolate backwards in time we reach a point where the universe is simply not big enough to contain all of its information. What am I missing?

[Possible spoilers?] During the Moon mission where you have to get Dinklebot to download the data from the World's Grave, he mentions that the Hive have somehow broken the Bekenstein limit. It made me curious, and the TL;DR of it is that this is the theoretical limit of how much information can be stored in a given space. Thanks for making me smarter, Dinklebot! You may now return to opening locks very slowly.

http://en.wikipedia.org/wiki/Bekenstein_bound

I understand that it a upper limit of information that can be stored in a confined space, but does it apply to only large scale/theoretical space or does it actually exist and can be used to describe something like a hard drive with 500 GB of space and you have 499.99 GB of data you are approaching the Bekenstein limit of the hard drive?

My understanding was that experiments such as the Lorentz invariance results achieved by Fermilab in 2009 put the minimum "pixel size" for the universe (if the universe is discrete at all) to well below the Planck length. Doesn't this imply that the information needed to store even the position/velocity of a single photon would be higher than the Bekenstein bound for a volume enclosing it?

Is there a contradiction here? If not, why not?

I checked the wiki and I still have no clue what they are saying.

Perhaps this is because I'm not normal, but I simply cannot accept this limited reality as it is. I see this world as being a world of crude limitations, where infinity can never be reached or even approached past a certain point. The laws of physics impose all kinds of limits to all aspects of life, from physical to psychological to technological to social. I find this world of the finite and mortal simply repulsive, simply because things are finite, and are bound to decay and repeat.

The Universe was never made for my optimal enjoyment, so I guess this is to be expected. But I just can't stop fantasizing about living in a better world, a world where everything goes right and there are no limits to what one can accomplish. A world without information limits, speed of light limit, no Bekenstein bounds, limits to the amount of things and how they can be arranged, or limits to how intelligent and wise one can get. I want to live in a world where one can choose to live forever and enjoy it, instead of being cursed by technological limits and entropy. I want a world where everyone can choose whether or not to exist. I want a world where everyone can choose how intelligent/educated/creative they are at the click of a button, where no education is necessary. I want a world where nobody has to work and resources are unlimited and free, making money non-existent. I want a world where space isn't an issue. I want a world where gravity isn't an issue, or any other phenomenon. I want a world where one is free to do what they want, whenever they want, as long as it doesn't cause suffering. And most of all, I want a world where suffering and boredom are non-existent.

Knowing that this Universe is full of limitations and finitudes causes me great suffering. I have a saying in my head; "The Garden of Potential Knowledge is Infinite". I believe knowledge/information has no bounds, from the perfect chess game(s) to all the digits of pi. You just have to have the necessary amount of computational power and memory storage to grasp them. However, in this Universe, the amount of power and memory possible is finite. This is one of the biggest things that bothers me, as someone that is fascinated by math, science, and the concept of infinity. I hate the fact that there will always be something unknown. And worst of all, I know that my dreams will probably never come true, and even if there was a world like I describe, that world will probably be full of suffering, and thus im

I saw this article: https://www.google.com/amp/s/www.space.com/amp/29477-did-information-create-the-cosmos.html

And this reddit comment: https://www.reddit.com/r/Physics/comments/ibmgkk/comment/g21u227/

That both made somewhat compelling points towards reality being made of information. I also saw this article: https://www.google.com/url?sa=t&source=web&rct=j&url=https://blogs.scientificamerican.com/cross-check/why-information-cant-be-the-basis-of-reality/&ved=2ahUKEwi-5Ojoouz0AhVPgXIEHQRUCoIQFnoECAUQAQ&usg=AOvVaw0Naz0j6qJuDJ2u1uiD9a5X

That implies the opposite. Kinda confused on which points to believe, was hoping for some help here.

Edit: I also saw these two wiki articles: https://en.m.wikipedia.org/wiki/Bousso%27s_holographic_bound

https://en.m.wikipedia.org/wiki/Bekenstein_bound

That both mention this idea that information is fundamental, or not a human made construct

I'm trying to understand the quantum Bekenstein bound, and the equation refers to something called a modular Hamiltonian.

Specifically, the Von Neumann entropy of the excited state minus the Von Neumann entropy of the vacuum state is less than or equal to the modular Hamiltonian in the excited state minus the modular Hamiltonian in the vacuum state.

I'm hoping for a fairly simple explanation, not something overly technical. Not that I would necessarily not be able to understand a technical explanation, but right now that's just not what I need.

I don't want to step on anybody's toes here, but the amount of non-dad jokes here in this subreddit really annoys me. First of all, dad jokes CAN be NSFW, it clearly says so in the sub rules. Secondly, it doesn't automatically make it a dad joke if it's from a conversation between you and your child. Most importantly, the jokes that your CHILDREN tell YOU are not dad jokes. The point of a dad joke is that it's so cheesy only a dad who's trying to be funny would make such a joke. That's it. They are stupid plays on words, lame puns and so on. There has to be a clever pun or wordplay for it to be considered a dad joke.

Again, to all the fellow dads, I apologise if I'm sounding too harsh. But I just needed to get it off my chest.

Do your worst!

I'm surprised it hasn't decade.

For context I'm a Refuse Driver (Garbage man) & today I was on food waste. After I'd tipped I was checking the wagon for any defects when I spotted a lone pea balanced on the lifts.

I said "hey look, an escaPEA"

No one near me but it didn't half make me laugh for a good hour or so!

Edit: I can't believe how much this has blown up. Thank you everyone I've had a blast reading through the replies 😂

It really does, I swear!

They’re on standbi

Because she wanted to see the task manager.

Pilot on me!!

Nothing, he was gladiator.

Dad jokes are supposed to be jokes you can tell a kid and they will understand it and find it funny.

This sub is mostly just NSFW puns now.

If it needs a NSFW tag it's not a dad joke. There should just be a NSFW puns subreddit for that.

Edit* I'm not replying any longer and turning off notifications but to all those that say "no one cares", there sure are a lot of you arguing about it. Maybe I'm wrong but you people don't need to be rude about it. If you really don't care, don't comment.

When I got home, they were still there.

What did 0 say to 8 ?

" Nice Belt "

So What did 3 say to 8 ?

" Hey, you two stop making out "

I won't be doing that today!

[Removed]

Where ever you left it 🤷‍♀️🤭

This morning, my 4 year old daughter.

Daughter: I'm hungry

Me: nerves building, smile widening

Me: Hi hungry, I'm dad.

She had no idea what was going on but I finally did it.

Thank you all for listening.

You take away their little brooms

There hasn't been a post all year!

It was about a weak back.

I am referring to this: http://en.wikipedia.org/wiki/Bekenstein_bound