Computing a Universe Simulation

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Physics seems to be telling us that it’s possible to simulate the entire universe on a computer smaller than the universe.
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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Luke Maroldi
Assistant Editing and Sound Design by Mike Petrow
Made by Kornhaber Brown (www.kornhaberbrown.com)
I’m not saying the universe is a simulation. I mean it might be - I’m just not saying it. And perhaps it doesn’t make any difference. Even if this is the prime, the original physical universe, rather than somewhere deep in a simulation nest, we can STILL think of our universe’s underlying mechanics as computation. Imagine a universe in which the most elementary components are stripped of all properties besides some binary notion of existence or non-existence. Like, if the tiniest chunks of spacetime, or chunks of quantum fields, or elements in the abstract space of quantum-mechanical states can either be full or empty. These elements interact with their neighbors by a simple set of rules, leading to oscillations, elementary particles, atoms, and ultimately to all of the emergent laws of physics, physical structure, and ultimately the universe.
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سلطان الخليفي

[@CevelNet]

You know you did an extremely good job at AI programming, when the characters in your simulation start wondering if they are simulated.

[@cartermason3275]

InstaBlaster...

[@karana2260]

Nice point! if its a completely random system like game of life, with everything and anything happening, wont there be a chance that characters will pop up with consciousness in all the randomness? Or to say high entropy states will occur.

[@krinodagamer6313]

yep

[@krinodagamer6313]

I just said that the day we can simulate a simulation where people or animals has self awareness then Ill believe we are in a simulation everything is based on quantum and binary codes

[@l1mbo69]

@@karana2260 you have misunderstood what a game of life is. It is NOT a random board where anything and everything can happen, there are simple rules for interaction in place

[@DeGebraaideHaan]

Your universe needs to restart to install important updates...

[@alarafatlemon3219]

LoL

[@william41017]

That was the KT event

[@irvingchies1626]

Dammit Microsoft, your effing update deleted most dinosaur files!!!

[@victorrielly9363]

So that’s why Big Bang.

[@AspLode]

Not now, Adobe Reader!

[@terryboyer1342]

I've always imagined our "universe" was just a junior high school kids entry for a science fair in the real universe.

[@alexeysamokhin9629]

Real?

[@mixnewton5157]

because you don't actually know how complex is reality

[@adamlindfors5082]

If its that easy that person should also living in a simulated universe

[@matthewprovencio6020]

A goldfish in a bowl basically

[@terryboyer1342]

@@matthewprovencio6020 Or an ant farm.

[@matta5498]

If it's a simulation, thank God it allowed me to experience the 80's.

[@Therealwaweezy]

You must be a white dude!

[@antontomov8532]

@@Therealwaweezy You mean the admin. :D

[@rogerab1792]

and if it isn't, thank God/chance anyways

[@rashardmitchell7915]

The 80s was awesome 🥳

[@kamakirinoko]

No, I experienced the real 80s. You just experienced a simulation of the 80s. Thus, Sting. (And Michael Jackson).

[@ToastedFanArt]

Dang that Switzerland dig was savage... Edit: For those that missed the joke, he said Switzerland was also "a non-rotating, neutral black hole".

[@shashankramesh6982]

Why did he say that? I didn't understand 😅

[@LoverKittey]

the roast is strong with this one.

[@fllthdcrb]

"Neutral ... again, like Switzerland". I'm pretty sure that was it.

[@ferdinandkraft857]

Now I know why LHC was built in Switzerland...

[@Quantum_GirlE]

love your pic!

[@EldafoMadrengo397]

That Anti aliasing line lol xD

[@Fittiboy]

What a horrible mess reality would be though :D EDIT: We'd probably have different standards of beauty. Either our own form of AA or just embracing the jank and looking like Minecraft skins.

[@amicloud_yt]

A bit of a groaner but a 5-star joke nonetheless.

[@side-fish]

But what about ray tracing XD???

[@clairecelestin8437]

I appreciate that those with sufficient information storage and processing to answer the challenge question are awarded a prize proportional to their surface area

[@NaumRusomarov]

This is probably one of the more fundamental episodes as it shows that the universe might be informational in nature.

[@Jordan-zk2wd]

Actually Switzerland is rotating, so a nonrotating neutral black hole isn't perfectly analogous to Switzerland.

[@TheNipSnipper]

reeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

[@ilxstatus]

Also, as a flat Switzerland-er, I find the analogy of black hole to Switzerland very offensive.

[@mokopa]

Switzerland does not rotate relative to anything significant, so, no.

[@youteubakount4449]

how can switzerland rotate if earth is flat...

[@insertdeadmeme]

youteub akount Switzerland can rotate because the earth is neither spherical nor flat but rather cylindrical

[@mattio79]

In a 1D world, are there Point-Earthers?

[@u.v.s.5583]

That's ridiculous. Everybody knows this planet is a finite open interval!

[@balrighty3523]

For that matter, in a 0-dimensional universe, are there "-1 Earthers"?

[@michaellv426]

Our Universe is a folded sheet of 2d space which is itself a folded 1d line of fixed-size points. At any given time, you can move on this thread only strictly 1 step left or right, but you can choose a step size from 3 options: x^0, x^1, x^2, where x is the length of one strand of this weaved space, equal to the length of the side of the Universe. By moving left or right by exactly x^0, you're moving left or right. By moving by x^1, you're moving back or forth, and by moving by x^2, you're moving up or down. So the Earth itself is a set A of several sets B of several line segments whose length varies from 0 to 12000 kilometers. Those segments are miraculously organized, i.e. lines of one member of set B are separated approximately by x^1, and those sets are separated approximately by x^2 on a universal thread, - that it gives an impression that the Earth is a sphere. While in fact it's just a mess from disjoint line segments, like everything else in this shitty universe.

[@cyberspore00]

mattio79 Pointless-Earthers

[@georgeabreu6392]

In a n dimension universe, are there (n - 1)ers?

[@wazzzuuupkiwi]

I really respect pbs's dedication to proper pronunciation. the amount of times I've heard "Swarts Child" over 'Swardz shild' made this episode refreshing

[@lawrenceshuda]

I love your humor! I enjoy chuckling while listening to you talk. I hope you continue these videos, for a very long time. Thanks.

[@alexjjgreen]

maybe turn off those ram hungry extra dimension visuals in settings

[@lwazishangase331]

NanoTree It just won't run without them. 😔

[@thstroyur]

Or install a GPU

[@HowBoutUHandleDeezNutz]

Visuals? Boi, 3 spacial dimensions and 1 of time are more than visuals

[@Erikulum]

"unfortunately you can only read out the simulation result... in hawking radiation" Made me laugh way too much

[@thstroyur]

There's C, Fortran, Java... but the real nerds program in Hawking++

[@colinfenn2517]

"Maybe if we turned off Anti-Aliasing...?" I'm dead. This line killed me.

[@jacoblongwell6419]

we are going to need a better compression algorithm.

[@jardy3597]

Hey Matt. I think the fact that we cannot simulate the universe within our universe is dependent on one assumption. The assumption is that we need to simulate every atom. Which might not be correct per se. If we look at the Delayed Choice experiment, we can see that photon's paths are not calculated as if they are particles unless they are observed. I'm a Software Engineer, and if i had to write a program that would simulate the universe - that's the same thing I would do. I would abstract things into simpler items. So light becomes a basic wave that consumes an order of magnitude less computing power than if I calculated each photon. Same goes for all kinds of particles. Why do I need to calculate what each atom in a core of a planet is doing, if i can just simulate a planet good enough to not be distinguishable from a 100% simulation? Only when the particles are being directly observed, would I use 100% simulation, to hide the fact that it's a simulation. In my opinion, this will allow us to simulate the universe to be indistinguishable for the average observer, in real-time. Cheers.

[@ecicce6749]

If you do that your Simulation is not correct and lossless anymore and is very likely to become unstable over time

[@journey8533]

At the beginning of the video they say that you need to represent the quantum States, not the atoms. I believe there is a fundamental difference there.

[@Zithorius]

Ecci Ecci Just like ours. It is in fact theorized that over time a quantum fluctuation could rip the entire universe apart as causality continues onward.

[@akrybion]

@@ecicce6749 Maybe that's where Dark Energy comes in. It's actually the simulation losing accuracy (which simulating a certain amount of gravity somehow prevents).

[@jardy3597]

Will I? Light works exactly the way I described and the universe is just fine

[@IanGrams]

Oh snap I got picked. Hi Mom! I will cherish the t-shirt immensely.

[@willypataponk]

I love this channel! You manage to explain very complicated things in a "simple" way. Keep up the good work!

[@RamzaBeoulves]

"That makes some intuitive sense" *Looks around* Yeah totally!

[@freesaxon6835]

Some very amusing computer related analogies

[@zero132132]

If you can simulate the universe on a computer smaller than the universe, then can you simulate that simulation on something even smaller? It seems like the implication should be that the universe has limitless computational capacity if that's the case, but I don't get how that could make sense

[@ToyokaX]

I think that he mentioned that such a simulation would not include things like Dark matter and all that, so it's not a 1:1 simulation of the full universe.

[@Prospektism]

ad infinitum

[@jaredgraham4022]

Each subsequent simulation is simulated at a slower speed so if you keep simulating universes inside each other an "infinite" times over you'd approach computational speeds of "infinitely slow". So no it doesn't have infinite computational capacity.

[@timbeaton5045]

I thought the implication would be that if you could run that simulation, in a smaller space than itself, it would NOT be an infinite regress...sooner or later, the processing volume if it did reduce, would become a black hole.

[@noahhounshel104]

You could, provided you had the nessicairy memory, simulate the universe using an 8 bit computer. Its impractically slow, but we're already taking longer than the heat death of the universe to calculate to "last Monday" soooooooooooooo Its absolutely possible. Anything has "limitless" computational capacity so long as it can compute, but because its computational speed is much slower it balances out.

[@SonOfPepsi]

When I started watching this channel, I sort of had a grasp of what was transpiring, but with each new episode, I become more and more perplexed.

[@hoffmankspengineering2034]

I have a bit of a theory regarding a computational universe: essentially, gravity wells form around areas where there is a lot of mass and energy. The more particles are packed into a space, the more interactions happen between particles and thus the more information that is being processed. Now, (here is the part where I make an assumption) IF the universe has a decentralized computational bottleneck ( in other words, the more computation happening in a localized area, the slower it goes ), it would create a time dilation effect around gravity wells similar to what happens in relativity. Black Holes would then be areas where the computations are queueing up faster than they can be processed.

[@mememem]

What if the universe is pre-rendered? And/or compressed with lossy algorithms?

[@cholten99]

In a previous video I mentioned the idea of procedural generation. That way you could potentially generate the state of the universe with a much smaller amount of underlying data.

[@Alaric323]

Then the future and past can't be changed (because it's a CGI film in reference to a video game) and details similar to one another are ignored by the compression. ...which would explain dark matter because then a large amount of mass focused in a single area would be compressed into a single chunk, but the original interpreted it as spread out, affecting the spin rate of galaxies and the like.

[@Joiner113]

@@cholten99 surely this is represented in the notion of deterministic natural laws? If not, we have to imagine a "pre-rendered" world where some or all events are predetermined.

[@snbeast9545]

SST is a pretty lossy algorithm. And if the universe is pre-rendered, that'd imply two things: 1. We have no free will, and 2. This universe is, was, and will be the same as the one that rendered it.

[@markstanbrook5578]

SNBeast there’s no mechanism for free will in any physics, simulated universe or otherwise.

[@ChrisBrown-pw2lb]

I dont understand half what is going on here. BUT I'M LEARNING! To everyone who worked on these videos. Thank you.

[@HowBoutUHandleDeezNutz]

Baby steps, 1 day it's Vsauce the next it's Isaac Arthur

[@HowBoutUHandleDeezNutz]

Even better

[@ParalyzedSociety]

Isaac Arthur is next level interstellar science shit!

[@u.v.s.5583]

One definitely learns much about Switzerland from this!

[@sirdgar]

You explaian everything so well...thank you….cheers

[@knasigboll]

"And you'll never need to defrag again..." I haven't done that in ages. Thanks for reminding me!

[@GameCyborgCh]

*laughs in ssd*

[@iseo247]

Why does everybody always assume our universe would be simulated from within itself, that would be boring for the programmers of that simulation. But what if our universe is being simulated from another universe with different laws of physics, e.g. maybe where the speed of light is faster, then it would be much simpler to do all those computations. :)

[@kyjo72682]

Exactly what I thought.. it could be much easier to run the simulation from one level up. We should assume only the necessary minimum about the potential simulator's universe. But from our perspective it doesn't matter how fast we would be simulated anyway. It could take years to compute a single frame of Planck time and we wouldn't notice. unless of course we were connected to the game from the outside. In that case we would notice the lag. ;)

[@badlydrawnturtle8484]

Indeed, I would argue that this whole ‘you need an absurd amount of computing power to simulate your own universe’ thing is true for most universes, potentially all of them. That would imply that any simulation would almost certainly be of a simpler universe than the universe the simulation is taking place in. It's not only possible that there would be a more ‘powerful’ universe simulating us, it's probable.

[@brokrokdale4909]

Infinity is too big how do you downsize it??? #Sciencethat

[@tomc.5704]

+Badly Drawn Turtle But it goes both ways. The universe above us is A.) much larger and more complex than our own and B.) also a simulation. Points A and B apply recursively. The only way to around that is to find a way to simulate a universe of the same complexity or greater than our own from within our universe,* or to accept that somewhere along the line there's a universe that's NOT a simulation. But if that's the case, why not this one? *I guess you could also claim that one of the parent universes has different laws of physics that allow them to accomplish this. That would certainly allow our universe to be a simulation, but it's a real cop out.

[@McMostaza]

Also consider that the sim could be slower than "real time", and we would never be able to know (not great for the operators, but maybe they are very patient) -- edit: video hints (?) at this, but more liberating with an unknown outside universe

[@JohnGrahamsBlog]

Was the camera on Matt out of focus in this episode?

[@TheReaverOfDarkness]

No, it's actually the difference in travel time of the different wavelengths of light, as their speed is reduced by traveling through the air between Matt and the camera.

[@catcollision8371]

No, you're just watching the simulation on low settings, it's probably running on a low spec machine.

[@Tom_Het]

No, you just need to put on your glasses.

[@Deffcolony]

I think the simulation is running on a low spec MS DOS machine

[@influencer20XX]

This is exactly the video i was looking for. Thank you!!

[@seerexplorer9578]

*_Thanks for having subtitles or captions_*

[@moofymoo]

3:20 - is it possible to make a doomsday device that downloads cat videos from youtube and stores it all in tiny region of space to make a black hole?

[@TheDuckofDoom.]

Tiny black holes are not significantly more threating than an equivalent amount of mass without black hole density. A cannonball and a black hole with the mass of a cannonball will have the exact same gravity at [and greater than] the radius of the cannonball. Tiny black holes also evaporate rather fast, so I suppose the next thought is how fast and will it grow or shrink, a 1000kg BH has a temperature of 1.2*10^20K and a lifetime of about 84 nanoseconds, even if formed at the surface of a solid rock and allowed to fall through the rock under earth gravitational acceleration it would evaporate much faster than it collected fresh matter and would quickly cease to be.

[@thetechoasis2179]

@@TheDuckofDoom. that is not true even a black hole of 1/1000th of 1mm orbiting our planet would tear it asunder

[@Twilumina]

Thank you! You have no idea how much it bothers me when sci-fi uses the term "dimension" improperly! Oh, and great episode, as always!

[@insertswear]

Funny that you should mention Conway's game of life. I always thought of it as an analogy for how physics work, or why they work in the specific way they do in our Universe, as if a deeper set of rules underlies why particles are the way they are.

[@vincentsimmons2423]

Frickin kool, awesome, brilliant, and such. Thank u! Very much!

[@MsBobZero]

Could you make a video about communication/internet in deep space? I can’t find a lot about it on youtube. I’m wondering for example; how much time does it take to send a message from pluto or voyager 1 to earth? Love your channel by the way!

[@engizmo]

Yes the univerise is a computer and will always be while we keep exploring and defining it with maths. Surely thats no surprise?!?

[@Sa-fd7ih]

Matt’s narration is especially soothing in this episode 😄

[@zodiacfml]

You're so timely, again. I've been pondering this on the concept of space. Space seems infinite and that it could be just built with Math or compute.

[@mathematicalninja2756]

Summary after reading the comments of this and previous video This universe is an algorithm/computation which finds the answer to the question of life, universe and everything. As soon as someone finds the answer to this question, the universe will cease to exist for that someone. The information stored in the universe can be approximated by the surface area instead of volume. This could mean some godly compression algorithm is being used and it increases the possibility that universe has everything precomputed. If the universe consists of set of precomputed states it implies two things: 1. We have no free will, and 2. This universe is, was, and will be the same as the one that rendered it. Also, the universe just needs to simulate the approximate nature of universe according to the observer instead of simulating everything. This greatly helps the universe in storing the information by a lossy compression algorithm. The lossy nature leads to noisy artefacts such as appearance of particle from nowhere and disappearing into nowhere which is basically birth and death. If an algorithm defines the simulacrum that is our Universe, then it is timeless... it just IS. The universe, the past, present, future has always existed and the observer experiences this "reality" until he finishes the computation of finding answer to life, universe and everything.

[@ToTheNines87368]

Wot..

[@davidwright8432]

'This universe is an algorithm/computation' - slight caution: it can be seen as this, but that doesn't oblige it to be so. It may be, but that's a separate question - which not every one agrees on (among those competent to make such claims). In fact, the universe is the universe, whatever that is.

[@paulponsford]

I have just found the answ

[@gstylez0107]

Great post, this guy's a real thinker

[@mykofreder1682]

A single 0 or 1 for each particle is not a lot of information, there is nothing about location and a lot of other important things. It's basically an inventory of one characteristic and does not seem like a simulation.

[@svenvancrombrugge9073]

Hi Space Time! Thank you for the great video! I think you could save the information much more effective than you proposed (needing the Switzerland diameter black hole). Not to mention the possibility of compression you could save enormous amount of space by storing information implicitly, not explicitly. This might actually destroy the deterministic nature of the universe, but if you save emerging features, like atoms, or protons, etc. instead elementary particles. You could save a lot of space. Also if you can compute when e.g. a lightray / a single photon would interact somewhere. You would not need to save and compute it for billions of years, only store it compressed in a storage, that waits for such interactions. Especially computation wise this would make a huge difference. I don't believe in the "single electron" idea, but this idea kinda aims in that direction for other features.

[@lawrenceworrell591]

Really. Reeeeeaaaally. Good luck searching that entire space for the single interaction. You'd also have to know in advance that particular piece of data is needed for decompression and data search. But then you'd have to pull it out regularly and compute it's next steps then put it back then pull it out, compute put it back. You'd have to resolve the entire universe on each clock tick. Otherwise things like Oumaumamamia ( can't remember the name) wouldn't appear unless they are hand crafted occurrences.

[@IgorDz]

I only understood one thing - about defragging, and I feel proud!

[@CRASS2047]

It makes total sense and explains so much. Even explains and lends credence to the belief in a creator.

[@renzocalcagno6742]

No problem, my old Pentium will be able to do it

[@Toonj00]

My celeron can generate more than 2 universes at the same time!

[@Lexivor]

Ah, nostalgia. My fifth computer was a pentium.

[@irvingchies1626]

Pentium III is actually faster than pentium 4 in most scenarios

[@Soupy_loopy]

Is it just me, or are computers getting slower?

[@TheReaverOfDarkness]

Computers are getting faster, and browsers are getting slower.

[@pierreabbat6157]

Why did the universe simulation crash? The programmer forgot to initialize the Cepheid variables.

[@tomf3150]

Constants aren't, variables don't.

[@johngibbs3223]

Love the Game of Life Easter egg! The ‘walkers’ were especially fun. Brought back memories of programming that game as a kid. Nice, graphics, folks. 👍

[@albertgerard4639]

The animations in this video where extra super awesome

[@CinemaRockPizza]

You are off focus, dude - in that case you seem to be not fully rendered...

[@vincentlevalois]

I checked my res settings to make sure I wasn't in 144p.

[@Spiralem]

Graphical fidelity is sacrificed to compute the universe.

[@starscape539]

Quite understandable. After all, they only have the surface area of the universe to store the full volume of the computed reality of the universe.

[@aeropasta]

do you wear glasses?

[@ichbinein123]

He's off focus in every video. A bit annoying to be honest, considering their otherwise amazing production value.

[@H4kkk0]

The Line Earth conspiracy theory starts here now boys ! Let's go spread the word !

[@Okuni_]

i can barely understand things these channels has spewed out over the years but i still watch it

[@TusharSharma-km3bt]

If universe is a computer , there must be a way to clear the RAM (decreasing entropy)

[@Iamsofuckingspecial]

coronavirus)

[@xenithmusic3029]

Although we are dead the same amount of matter exists. Data cannot be removed.

[@melissawhite5116]

Not without breaking the rules. Nothing is ever lost...ever. it all breaks down if information is lost.

[@benbennit]

You only measure what you require during a microscopic slice of time.

[@andreys7944]

>If you want to include photons, neutrinos, dark matter, etc. Does it include black holes larger than Sag. A*?

[@LordMichaelRahl]

Didn't know about some of these principles, thanks PBS.

[@JustForComments666]

Is it possible possible that this universe is inside the black hole of a 4-dimensional reality? Like you explained in one video (penrose video I think) once you are in a black hole one direction becomes time. So could it be that inside the black holes in this reality there is a 2-dimensional reality and inside the black holes of that reality there are 1-dimensional realities? Like a never ending matryoshka of dimensions. Also, how is 1 bit per particle enough? Don't you need more than one variable to define position and momentum?

[@JosefHabdank]

8:31 thumbs up for using the sound of fireball from Doom 1 :) I have played the game so much I picked up on the easter egg :)

[@EMan32x]

I love this channel so much.

[@jacoboneill2494]

Very interesting! I love this show! I don't see how we'd ever get all the information we would need to enter into it. Nowadays, there's processing of encrypted data, which could reduce the requirements by quite a bit. Still, the processing and getting output would be extremely difficult. We don't know enough about cosmic rays and neutrinos to even start, now.

[@akashchandrabehera7667]

But sir the Margolus-Levitian theorem says that max. No. of Ops/sec a system can perform is ≤ 4E/h, thus if our black hole simulator starts to perform Ops then it's speed (i.e. Ops/sec) must decrease as the energy of the black hole decreases and it becomes smaller, so One must integrate the expressions rather than just division. Also you said that output will through slow Hawking's radiation but the output shall be transmitted immediately as the black holes performs Ops and loses energy. Why is there a time lag when the computation is taking place on event horizon (where the Hawking's radiation originates)?

[@stuffums]

I'm writing down my dream life scenario so when I die there might be a small chance I can chat with a simulator tech and ask to be put back in as this character.

[@nolanwestrich2602]

Hey God! Reincarnate me as a celebrity!

[@SuviTuuliAllan]

Isekai protagonist volunteer #3 here!

[@TheBackyardChemist]

Not a good idea, someone did that ~2000 years ago, and look where that lead

[@badlydrawnturtle8484]

What's the likelihood that someone running the simulation would pull out your code and reactivate it to talk to you after you die? It's not like people go around asking video game characters how they feel.

[@stuffums]

Like 1 in a quadrillion chance but better than 0, and I'll also request all weebs can be sent to a parallel simulation where Anime is real

[@lawrenceshuda]

This was a crazy video! I did enjoy it.

[@MeinDeinSeinCraft]

14:56 that was a good one 😂

[@RoySchl]

Book recommendation: Permutation City

[@Ryukachoo]

6:15 What the what? Did the EHT finish it's work way faster than I thought or is that a heavily tweaked cg rendering based on little data

[@Vinniewashere]

that's what I thought. made me wonder if since matt is a scientist and in the business they can get leaks of unpublished images would be sweet but the more logical explanation would be it's a rendering from EHT

[@watsisname]

It is a simulation of what an accreting black hole like SgrA* might look like, run by Hotaka Shiokawa. You can find many other simulations on the Event Horizon Telescope project's home page, as well as here on youtube. :) Running these simulations helps the scientists understand what to look for in the real data and how to use them to test general relativity's predictions.

[@luci75d76]

Ok. This rime you Really blow my mind. So many factors !

[@ThomasSorensen1]

The shirt you're wearing in this video - can you explain it? I remember it being something like, possible stable orbits around a black hole. But I'd love more details (e.g. it seems like rotation, or the lack thereof, would be relevant) and even a large print of this (could make a cool piece of art on a wall!) to purchase.... Thanks, love getting the notification for these videos!

[@priyapramesi6026]

I'm confused...wouldn't simulating the universe with something smaller and running faster than the universe itself lead to paradox? That means if you have simulation of the universe inside itself, you could build a computer that simulates the universe and itself, which then recursively simulate universes (and itself) infinitely. Wouldn't that require infinite storage space? Same problem arises when the computer is able to simulate the universe faster than the universe itself. If the computer is running faster than the universe, let's say by only 0.0001%, the computer can then simulate itself recursively and infinitely, making the speedup infinite (because then the future will have already happen in the simulation), which is a contradiction. Like let's say a computer can simulate arbitrary physical process that takes 2 seconds in real time in only 1 second. If it simulates itself, then after 1 second, the simulated computer will have ran for 2 seconds, which itself has simulated a simulation that ran for 4 seconds, ad infinitum. But that's a contradiction, because the original, physical computer can only simulate physical process in half the time, not infinitely. Am i missing something here?

[@danbaurceanu129]

No. This whole thing is one untestable wild speculation.

[@frankguy6843]

You're right, this is pretty much nonsense, an entertaining video but it approximates and estimates so much it doesn't make any real conclusion.

[@rubiks6]

As far as the size paradox goes, I agree with you completely, Priya. I also saw the problem, almost immediately. It seems so obvious. I'm really don't understand why Matt doesn't see it.

[@johnreza8746]

'If you assume the universe is evolving at the maximum computational rate' -- I believe the correct interpretation of this is that with a universe simulator that simulates at a rate much faster than the universe itself the simulation must always end up having less fidelity than the actual universe.

[@wasd____]

No, it doesn't lead to a paradox. The computer isn't simulating itself within the simulated universe, and the universe doesn't contain the maximum density of information (because if it did, it would be a black hole), therefore there it is possible to simulate a universe the size of the one the computer is in on the surface area of the event horizon of a black hole smaller than the universe itself.

[@MeinDeinSeinCraft]

0:33 this is not full HD! Is the camera out or focus or what?

[@alice_in_wonderland42]

yes

[@renatogolia211]

I love your videos! Do you think you could add a link to the videos you suggest in the description? That would help a lot!

[@ASAWProductions]

Weird to say this, but I loved the Chris had field Master class ad before this

[@vovacat1797]

"A non-rotating neutral black hole... Like Switzerland"

[@v.sandrone4268]

matter (gold) enters Switzerland and information never leaves it just like a black hole.

[@danieljensen2626]

Since the universe contains tons of black holes wouldn't you need to add all the black hole masses to those figures you came up with to actually simulate the whole universe, including black holes?

[@scotthammond3230]

This! How can you fit the universe into a galactic black hole, when you also have to include all galactic black holes? This makes no sense. You cant pack black holes tighter.. they just get larger. Does the 10^80 H count come from the initial big bang, or is this the current count excluding what has fallen into black holes? Second, if you dont include black holes in the universe simulation, this means that current galactic black holes have enough information inside of them to actually be separate universes.

[@MegaFonebone]

I think I can actually answer this one. The reason black holes don’t add much to the storage requirement or computational complexity of the universe simulation is that, informationally speaking, each black hole requires no more information (parameters) to describe than a single elementary particle. Just 3 parameters, in fact: charge, spin (angular momentum), and mass. If the “no hair” conjecture is correct, anyway. We’re not talking about fitting the actual mass of a black hole into our memory storage medium (which happens to also be a black hole, just because we’re visualizing the minimum possible space needed for all the information). We’re only fitting the information needed to completely describe a black hole. See, I can store all the information needed to completely describe an entire hypothetical Swarzchild black hole right here: {0,0,42}. The first parameter is the black hole’s charge, i.e., it has no net charge. The second parameter its angular momentum, i.e., it’s not spinning. The third parameter is its mass in solar masses.

[@danieljensen2626]

@@MegaFonebone Clearly you haven't been watching the rest of the videos in this series... Current theories suggest black holes retain all the information of every particle that ever fell into them and this information is imprinted in the Hawking radiation. Thus to simulate a black hole accurately you basically need a copy of that black hole or an even larger black hole.

[@zodiacfml]

They are somehow correct because black holes don't do much in the universe once it captures the particles inside. It's like a drawing a black circle in your computer program which is simple to do. The video only considered visible matter in the universe an approximation of the real universe, kindly like throwing out some information from a CD quality audio, turning it to an MP3/lossy compression file. However, I can argue that black hole mergers spread out a ton of energy through gravitational waves

[@danieljensen2626]

@@zodiacfml I'm pretty sure storing your simulation inside the big bang is cheating, haha.

[@alimibrahem8120]

My question is if we want to compare this simulation with Maxwell's Demon thought experiment, this means that this human mind has a very very high entropy, because he was a ble to return this universe to the state of low entropy (the beginnig of the universe) and he simulate this state on a computer, so does this mean that there was a source of a high entropy informations before the big bang, and this high entropy informations caused the state of low entropy at the beginning of the universe.

[@JordanEdmundsEECS]

Do black holes necessarily contain maximal information? Or is the Bekenstein bound a limit on the information they *can* contain?

[@Aidan42781]

I don't think we'll be stimulating universes atom by atom anytime soon but shouldn't it be possible to simulate smaller regions of space? Maybe a planet? A Solar System? Let's say you simulate the Earth in precise detail down to the last quark and gluon but simulate the rest of the solar system in much more crude detail. Then you simulate the rest of the Galaxy and universe in even cruder detail. Doesn't really matter if X Nebula light years away is just a fairly simplistic particle effect as long as any simulated life forms that develop don't develop near-light speed travel. We can take that one step further and say that we make some kind of algorithm so that finer details only render if something observes it. ... Wait a minute.... Nah, until the simulation hypothesis has a reasonable way to be tested it's largely irrelevant. But it's also interesting to talk about because I think there would be value in us humans simulating 'chunks' of universes. For instance, simulating the Solar System and seeing if it spawns life and how that process takes place.

[@AbsoluteArch]

You must also program the way every atom reacts with it's surrounding because any mistakes at the atomic level will scale into the larger image and change the results of a simulation. Most programmers rely on prewritten algorithms that mimic real life physics of motion, but that wouldn't work on a universal level.

[@WojtekWawrow]

Double hiccup at 8:39 - the 7 should be in the exponent with the 1, and the unit right next to it should be sec, not ops/sec

[@markmiller4414]

This episode reminds me of one of the first ever CG movies in the 1980s, The Last Starfighter, where we discover a space video game was placed here on Earth by an alien civilization hoping to find a high enough scorer to become a "starfighter". I wonder if Matthew O’Dowd and PBS SpaceTime are really space aliens trying to find the next Einsteins to solve their way out of a universe-ending cataclysm ;)

[@FdaApprvd]

So fun to watch

[@Sound_.-Safari]

I'd love to know the implications of theoretically computing a smaller universal simulation wherein the scope of the computation is only for a small area of the universe? Could you possibly outpace the computation of the real universe but only for a subset area of it?

[@mixnewton5157]

no it can't outpace, or even be as good as the universe, the problem with this video is not simulate the black holes, also having a lot of assumptions and over simplify the reality, we actually don't know exactly if the space-time is actually quantized or not

[@thekillshootable]

Since quantum particles only exist in so far as they interact with other particles, doesn't it make more sense to attribute the information of the universe to these interactions rather than the particles themselves?

[@nah6110]

I don't think so because interactions between particles would be the result of computations in a computer.

[@kylemiller2414]

But the particles have to have some kind of fundamental value in order to interact, right?

[@vrzrea795]

Hello, thaks for the video. Does the supermassive black holes at the center of the galaxies contain more information than the observable universe? Thank you.

[@eddiegaltek]

I thought of this, about the universe, the first time a saw Conway's Game of Life running, about 30+ years ago.

[@edemilsonlima]

This universe is expanding because of an endless loop that is filling up memory in God's computer.

[@TheFlyingTVsNOW]

And thats why only the ones God remembers will be saved. Only confessing you're sins to Jesus and asking for forgiveness will save you. Amen

[@Iamsofuckingspecial]

buffer overflow = coronavirus

[@raptecclawtooth9046]

This universe is a troyan!

[@PoppyB2011]

@@TheFlyingTVsNOW Comment brought to you by the Onion.

[@BradWatsonMiami]

== The Conglomerate - Universe Creation Theory == combining GOD/Nature, GOD=7_4 or FOD=6_4 theory, ancient religions, astronomy, cosmology, laws of physics, general relativity, quantum mechanics, chaos theory/fractals, laws of biology & chemistry, linguistics/code-breaking, computer programming, mysticism, and philosophy "Energy can’t be created or destroyed, only transformed/transferred in an isolated system." General relativity allows black holes, white holes and Big Bang. 'The BIG Bang-Bit Bang' inflation/expansion of energy and information into the void 13.8 billion years ago was a supermassive white hole spawned by a supermassive black hole at the heart of a galaxy in our 'parent universe'. This duality combines general relativity’s singularities of infinite density breaking through spacetime in ‘Cosmic Egg hatchings’ of all created universes within 'The Conglomerate: multiverse with no random quantum fluctuation bubble universes, no parallel worlds, and no universe with different physical laws. Our Universe is 1-in-2 trillion 'self-similar offspring' each with the same inherited ‘DNA’. "In the beginning”, the Planck density of the core of a SBH is a birth canal. 'Quantum bounce SBH-SWH seed transitions' are 'quantum tunneling umbilical wormholes' with energy-matter and data transformed/transferred, albeit scrambled and encoded. The ubiquitous cause-and-effect 'circle of life cycle': birth-life-death-transformation-rebirth explains infinite space and eternity - a necessity. Reproduction is GOD/Nature’s plan for greatly spreading life from cells to universes. GOD=7_4 or FOD=6_4 is the #1 program/law/initial condition (see GOD704.fandom.com ). Why does this Universe exist? It’s our playground (god + run = ground). - Seal #1a of the “7 Seals” revealed as ‘Beyond Einstein Theories’; see 7seals.blogspot.com . Only the returned Christ & Albert Einstein reincarnated could produce this. It's triggered The Apocalypse/Revelation which is NOT the 'end of the world'. COVID-19 is part of Seal #4

[@CanorousFlatulence]

Does this mean that sagittarius a* has as much...stuff in it as the entire observable universe has matter and radiation? Roughly speaking, of course.

[@lamacat]

This is what I was wondering as well. Surely you couldn't store all the information of the universe into a space that size when there are countless bigger black holes that would require their entire surface area to be described

[@zodiacfml]

11:26 I agree. We already are applying/using these in the real world, computer virtualization or virtual machines. Virtual machines can never equal its host in terms of compute/storage.

[@Kynk]

If we thought of a plank length as a pixel, what approximate resolution do we see the world in?

[@ghyslainabel]

Question unrelated to the episode. 1- We know the universe is infinite, or at least big enough that we see only a part of it. 2- There should be as much matter as antimatter. 3- We do not see a frontier where matter and antimatter annihilate each other. So, is it possible that the distribution of matter and antimatter is uniform only in the largest scales, and we just just happen to be in a place where the frontier between our section of matter and outside antimatter is outside the observable universe?

[@xhelloselm]

It would be strange that everything else we observe is very evenly distributed even across the observable universe while antimatter is not and only even across larger scales. But sure, in principle everything is possible.

[@timothymclean]

Is it possible? I suppose. But AFAIK, there's no reason to think that the discontinuities should be that large. If a theory was developed which had that as a prediction, and its other predictions bore fruit, we might solve the problem. Until then, it's just more speculation to throw on the pile. (Also, we don't have any clue how much universe there is beyond the observable.)

[@ghyslainabel]

Unaussprechlicher Name, I expect there was a lot of annihilation in the first few moments of the universe, and the gamma rays produced are lost in the microwave background by now. The only matter and antimatter left would have been in separate pockets to still exist today. The initial annihilation would explain why the distribution is not as even as everything else on smaller scales.

[@tabularasa0606]

What if the anti-matter is just moving in negative time.

[@ghyslainabel]

Timothy McLean, of course it is only speculation. But I have to ask, how certain are we that the universe should be exactly the same as the observable part we are in. I sometime wonder if we are doing the same mistake on larger and larger scale: the Earth is the centre of the universe, the Sun is the centre of the universe, the observable universe is an accurate representation of the whole universe. If someone with a physic background could prove me wrong, I would be happy to read the explanation.

[@gb-nz]

Let me roll one and watch again

[@DBoonful]

Excellent Video as usual. Keep up the fantastic work. Have you been studying posture? This is the first video Ive seen where your stance and hands look pretty relaxed -I miss the old stance where you always looked like you were going to pounce out of the video and grab the viewer by the throat to get your science points into their heads.

[@regularjoe6137]

Love the videos

[@markfudge5642]

If a computer creates a universe, Isn't it then a universe ?

[@DanielDogeanu]

Indeed. Maybe this is exactly what we are. A simulation of an highly advanced civilization trying to figure out their own Universe.

[@markfudge5642]

As long as we are not in an advanced version of The Sims.

[@burnhamist]

Microverse

[@ovidiudans]

Teenyverse

[@LyubomirIko]

Or we are the escaped souls of entities that have lost its own Universe due to heat death of their Universe

[@UpcycleElectronics]

14:57 Toe the line Matt. Toe the line.

[@todmann67]

I was hoping someone else saw that.

[@LaughterOnWater]

By "Universe" we're of course talking about the observable. How do we handle edge detection in our model? Because whatever is outside the observable will still affect our model.

[@georgehugh3455]

Makes sense - _the Heisenberg Uncertainty Principle is just the computer's way of interlacing for a faster refresh rate_

[@HauntaskhanHYPNOSIS]

I thought about this once, then I realized that my brain doing this was the powerful computer I was looking for.

[@kyjo72682]

Your brain doing what? Simulating the universe? Nah..

[@WaveOfDestiny]

I can barely run halo on my brain

[@LyubomirIko]

I can imagine simulating the Universe - its vast spaces and unlimited galaxies, all rule by my thoughts. It is pretty easy than actually make my dinner, ah the irony! XD

[@Zatmos]

My brain can simulate 99% of the universe. The vacuum part that is.

[@astroadventures3559]

Booooom!!!! Mind blown😦

[@UserAnonymus1995]

What if you take a small volume and make a fractal-like 3D shape out of it? We could get a way bigger surface area than what we’d get by shaping that volume into a sphere. Would we also magically be able to store more information in that volume?

[@ferdinandkraft857]

Annie - nope, that's not the way the Bekenstein bound works. Check its wikipedia page.

[@aeropasta]

Triply-Periodic Minimal Surfaces

[@dogwaffles]

You have to find the perfect balance between getting your mind blown and not understanding a word to keep up with this channel.

[@PhiladelphiaPhilms]

Thanks for the "Digital Physics" shout-out! Can we rule out a small Kolmogorov-Chaitin complexity for the universe (i.e. a small classical algorithm)?

[@Anonomousxxx]

What if simulate only the part of universe to which human can get to? No need to simulate all the long away stars and galaxies in detail

[@goofsterngafster8411]

Butterfly effect in the universe The atoms in your body were created in a distant supernova

[@petermoygannon698]

exactly they don't need distant gallaxys to be useing much power just coulerfull dots. in other words low download power to create. we never going to get there and they know it. we're stuck here . mabee mars at best.

[@goofsterngafster8411]

@@petermoygannon698 what about the fact that gamma ray burst 5000 ly away may have already caused one extinction event here on earth How do you account for that?

[@petermoygannon698]

@@goofsterngafster8411 has that happened.

[@goofsterngafster8411]

@@petermoygannon698 yes, scientists say may have happened once

[@TheTwick]

The answer to the question is 42

[@Ebani]

The question was?

[@JavRexgteneg2pIift]

Says the comment that was posted 42 minutes ago.

[@Forty2de]

you're not wrong

[@JB_inks]

Yet another predictably and boring comment. Sigh.

[@tabularasa0606]

Ebani If you know both the question and the answer the universe will collapse and a new even more confusing universe will appear.