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The frame rate of the universe (2009)

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Re: The frame rate of the universe (2009)

#21

Post by joshualedbetter »

AnIdiotOnTheNet wrote: post #14
tutfbhuf wrote: post #11

He did the monster math and calculated that the frame rate of the universe is 18 septillion FPS. Let's assume we are already in a game running with this FPS. Could we somehow prove that it's actually a simulation or disprove in the case it's not?

I think a more interesting question is: would it matter if it were?

Imagine a robot trying to argue that it doesn't if they live in Westworld; I mean, the robot bar tender still has to tend bar. Imagine Truman trying to convince himself that it doesn't matter if he's in a TV show or not.

Their arguments, no matter how clever, would be absurd when looking in from the outside.

If there's a high probability that the simulation hypothesis is true, it seems clinically insane to believe that it doesn't matter.

Re: The frame rate of the universe (2009)

#22

Post by tutfbhuf »

AnIdiotOnTheNet wrote: post #14
tutfbhuf wrote: post #11

He did the monster math and calculated that the frame rate of the universe is 18 septillion FPS. Let's assume we are already in a game running with this FPS. Could we somehow prove that it's actually a simulation or disprove in the case it's not?

I think a more interesting question is: would it matter if it were?

It depends on who you ask. I personally would like to have an answer to that question if it exists, but if it doesn't well that's okay too.

Re: The frame rate of the universe (2009)

#23

Post by xelxebar »

For those interested, the "3D projection of a 2D surface" that the author mentions is more formally called AdS-CFT Correspondence[0]. The AdS stands for "Anti-de Sitter spaces" and CFT for "Conformal Field Theories". This finds that the "surface" of the former looks like an example of the latter.

Man, the author has stumbled onto such a cool bit of physics/math. Wish I could ramble on about it more, but I'm about to head to work. Hopefully, someone else can elaborate!

[0]:https://en.wikipedia.org/wiki/AdS/CFT_correspondence

Re: The frame rate of the universe (2009)

#24

Post by CodexArcanum »

gzalo wrote: post #3
jdmoreira wrote: post #2

My physics almost stopped at Newton but I liked the article because it resonates with some thoughts I had about Zeno's arrow paradox - https://en.wikipedia.org/wiki/Zeno%27s_paradoxes#Arrow_parad... What if space is discrete and time is also discrete? Then there is no paradox. It disappears. I find the possibility that the Universe computes in `ticks` and space is discrete to be very soothing and I'm sure it has noth…

Some years ago, when learning about quantum mechanics, and how you could find a particle inside a forbidden region, I connected that with physics engines in games (and how computing them not fast enough can cause things to intersect in odd ways), and I had this idea: What if time flows in discrete steps, but the `ticks` aren't uniformly separated? For example, they could be distributed probabilistically as a Poisson…

There's a theory on how the universe is structured that instead of space-time being like a uniform grid, a Cartesian space, that space-time is made up of nodes which are linked together. I guess kind of like a voronoi diagram in 4 dimensions. I wish I could remember the name of those theories.

If space-time is packed together in most places, then it might resemble a grid to us. This model works in a lot of interesting ways too: wormholes are just links between two otherwise unconnected regions, the curvature of ST can vary depending on the region, and time can flow at varying rates depending on how "dense with time" an area is.

One thing I like about it is that Planck units kind of just represent a minimal distance between nodes (indeed, the connections between nodes defines "distance" and "duration") and everything else just falls out of the geometry of this ST graph.

Re: The frame rate of the universe (2009)

#25

Post by alasdair_ »

tutfbhuf wrote: post #11

He did the monster math and calculated that the frame rate of the universe is 18 septillion FPS. Let's assume we are already in a game running with this FPS. Could we somehow prove that it's actually a simulation or disprove in the case it's not?

I think it's possible to detect if we're in a simulation or not. I think of it in a similar way to detecting whether or not a system is running in a virtual machine or on the hardware machine itself. Even if the VM is really, really good, there may be sidechannel tests that can be done, like measuring the amount of heat generated for a given computation, or weird timing attacks, or edge conditions that affect the underlying hardware.

For every action taken inside the simulation, there will be things that happen on the "hardware" outside of the simulation and since it's simulated, not real, the "hardware" won't respond in precisely the same way as it would if it were actually real in every possible circumstance.

The only simulation that would respond in exactly the same way as a "real" universe under all circumstances has to be a perfect 1:1 mapping in terms of "universe hardware", which is exactly the same as running on "real" bare metal.

Re: The frame rate of the universe (2009)

#26

Post by logologology »

worker767424 wrote: post #8

> If we want to fit the universe into a box, its sides would have to be twice that size. That is 5.4 × 10^61 Planck lengths. 206 bits is enough to address the precise position of anything in the universe.

care to explain this one?

edit: right its log(2, 5.4*10^61). Its been a long morning...

Re: The frame rate of the universe (2009)

#27

Post by zamadatix »

alasdair_ wrote: post #25
tutfbhuf wrote: post #11

He did the monster math and calculated that the frame rate of the universe is 18 septillion FPS. Let's assume we are already in a game running with this FPS. Could we somehow prove that it's actually a simulation or disprove in the case it's not?

I think it's possible to detect if we're in a simulation or not. I think of it in a similar way to detecting whether or not a system is running in a virtual machine or on the hardware machine itself. Even if the VM is really, really good, there may be sidechannel tests that can be done, like measuring the amount of heat generated for a given computation, or weird timing attacks, or edge conditions that affect the und…

You can only tell it's a VM via sidechannel because you know what not-a-VM would do already. In the case of the universe we have nothing to compare to, no way to say "that's an effect of running on the underlying hardware" vs "that's a special case of how the hardware runs". E.g. one could take speculative execution rollback after certain workloads as timing jitter from being in a VM if they didn't know that's just how things work on a CPU and the instructions recently ran have an impact on how the next ones will predict.

Re: The frame rate of the universe (2009)

#28

Post by tutfbhuf »

alasdair_ wrote: post #25
tutfbhuf wrote: post #11

He did the monster math and calculated that the frame rate of the universe is 18 septillion FPS. Let's assume we are already in a game running with this FPS. Could we somehow prove that it's actually a simulation or disprove in the case it's not?

I think it's possible to detect if we're in a simulation or not. I think of it in a similar way to detecting whether or not a system is running in a virtual machine or on the hardware machine itself. Even if the VM is really, really good, there may be sidechannel tests that can be done, like measuring the amount of heat generated for a given computation, or weird timing attacks, or edge conditions that affect the und…

The problem with the VM example is that in this case you can actually compare the VM behavior with your knowledge of real bare metal behavior and try to detect differences. But what if you have nothing to compare to. If you are inside a VM and never heard of bare-metal and have no chance to get at it for comparison.

Re: The frame rate of the universe (2009)

#29

Post by pfraze »

gzalo wrote: post #3
jdmoreira wrote: post #2

My physics almost stopped at Newton but I liked the article because it resonates with some thoughts I had about Zeno's arrow paradox - https://en.wikipedia.org/wiki/Zeno%27s_paradoxes#Arrow_parad... What if space is discrete and time is also discrete? Then there is no paradox. It disappears. I find the possibility that the Universe computes in `ticks` and space is discrete to be very soothing and I'm sure it has noth…

Some years ago, when learning about quantum mechanics, and how you could find a particle inside a forbidden region, I connected that with physics engines in games (and how computing them not fast enough can cause things to intersect in odd ways), and I had this idea: What if time flows in discrete steps, but the `ticks` aren't uniformly separated? For example, they could be distributed probabilistically as a Poisson…

A few years ago, I saw a proposal for multiplayer games which suggested that the time passage between ticks vary depending on how many users are playing within a close space, to help deal with the increased network load. This is something that Eve Online does, but it segments its game-space into discrete sectors and therefore it slows down time uniformly in these sectors. This proposal was to do the same, but variably within one contiguous gamespace, meaning players would observe each other “slowing down.”

This seemed interesting to me because, well, what on earth would it do to your game physics to have varying time passage between ticks depending on your position in space? So I rigged up a simple simulation of 2 points connected by a spring force (a “body”), gave them an initial velocity, and set the tick to slow down linearly according to distance from a “center.”

The end result was that the body orbited around the center. The varying time passage meant that the spring force’s effect on the point masses would be reduced for the points in the slower tick speed. So it seems like you can create a kind of “gravity” by bending time but not space.

Here’s a link to the sim: https://pfrazee.github.io/gsim/

Re: The frame rate of the universe (2009)

#30

Post by pkt_nspktr »

rbanffy wrote: post #13

Kind of on the same vibe, you can think of the speed of light as the bandwidth of spacetime.

I recall a blog post or article posted several years ago, somewhere, that discussed the networking consequences of lightspeed being an upper bound for bandwidth. Unfortunately "lightspeed networking" is not a unique search term! Does this ring a bell with anyone and does anyone have a link to that article?
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