The Compendium of Doom, Part 2 (collab w/ Isaac Arthur)

WATCH PART 1: • The Compendium of Doom...
This is Part 2 of a collab series with Isaac Arthur. How will the universe end, and how is it connected to the mysterious dark energy?
Support: / pmsutter
Follow: / paulmattsutter and / paulmattsutter

[@hynjus001]

Any intelligent organism that evolves after the local group has merged will never have the concept of galaxy. For them Galaxy is universe. There'll be no way for them to improve their knowledge on this. This makes me think that when we ask "what happened before the big bang", we might also be living in an irreversible bubble of ignorance that we can never improve on.

[@xdarkknightx09]

Yeah thats what I was thinking. Or the big bang was the fundamental laws randomly changing to what they are now, and everything that existed, suddenly reacts to each other differently. Which causes a massive instantaneous chain reaction which we precieve as the big bang expanding from a singularity. Because we have no way of knowing or measuring what the universe was like before the laws changed. We will probably never know how it all started, as that could have also happened an infinite amount of times. Lets just say we are in a simulation and call it a day Kappa.

[@Ziplock9000]

Actually that's *maybe* not true. Intelligent life does not need direct evidence of something on order to discover something else. This is what logical deduction, reasoning and speculation is good at. For example we knew about black holes before being able to observe them them directly. The Higgs Boson was theory before any evidence was discovered of it's existence. Equally iron deposits on an isolated planet would be enough for an intelligent species to deduce the processes that created it. There will be countless other such ways that other things can be deduced.

[@HadzabadZa]

@@Ziplock9000 The point is, all your discoveries mentioned HAD some evidence to their existence, we didn't generate those concepts out of completely nowhere. But the more intelligent we are, the more indirect evidence we can use to discover something. What if existence of intelligence itself (we just need to advance it enough) is enough of an evidence to discover all of the universe's secrets?

[@Ziplock9000]

@@HadzabadZa Black holes and the Higgs were 100% just a theory for decades before being inferred via any evidence at all. The rest of your paragraph is just fun speculation that I can't really say anything about due to lack of evidence.

[@HadzabadZa]

@@Ziplock9000 I see what you mean, but by evidence I mean other observations. We wouldn't have theorised black holes, if we wouldn't have noticed that something massive, unprobably so, at least by contemporary standards. is pulling things around it.

[@JohnMichaelGodier]

Yay! Great collab guys!

[@EliLowkr]

It's collaborations like these that expand my scientific KZbin subs. That's how I met Joe Scott, Fraser Cain and the excellent John Michael Godier. Any suggestions on who else I'm missing out on?

[@UpcycleElectronics]

Eli Lowkr From my subs list: Scott Manley Anton Petrov David Butler DeepSkyVideos Deep Astronomy Vintage Space PBS Space Time SciShow Space Astrum Dreksler Astral That's most of my regulars list...on space/astronomy. The quality/style/depth vary but all are worth a look in my opinion.

[@timothycrystal2623]

Can someone explain this to me? If I have data that cars were driving away from me, and the data shows that an hour ago, the cars driving away are traveling at 100 MPH, and 10 minutes ago the cars were driving at 50 MPH, and so I conclude that the further away the cars get, the faster they are moving so therefore the expansion of cars is increasing... Instead, doesn't it show that the expansion is slowing? Since the more recent data indicates that the cars are moving away slower? That is the same data we have on the expanding universe. The older the light we see, the more red-shifted it is, while the younger (closer) light is less red shifted. Since the most recent data is that the expansion is slowing and the oldest data indicates that is was moving faster in the past... why do cosmologists insist that the further away the light is, the better indication it is of the current expansion of the universe?

[@PaulMSutter]

+John Michael Godier Thanks John!

[@IudiciumInfernalum]

Fancy meeting you here. I'm off to your channel now good sir, i've received a notification for a new video!

[@AtheistBelgium]

Arthur, stop sending me to great youtube channels. i now need 25 hours a day ...

[@R.Instro]

Only _now_ do you need the extra hour? I'm still waiting for the 37hr Argelian day from MiB!! ^_^;;

[@isaacarthurSFIA]

:)

[@jirivegner3711]

Or Venus :)

[@savasemanuel4541]

or europa

[@PaulMSutter]

+Occam's Razor Ha! Well just promise you'll only watch in your spare hour :)

[@dennisdahl3]

Dreams are what expands universe, love holds it together.

[@tedbell6523]

Both of you have wonderful content! Found Frasier Cain through Issac, then found Paul through Frasier. Nice to see you and Issac work together. I’m laying in a hospital bed after a spinal fusion yesterday, so you guys made my day, getting my mind off of being sore for a while. Thanks for the great work!

[@PaulMSutter]

+Ted Bell Glad we could help pass the time, and I hope you recover soon!

[@tedbell6523]

Paul M. Sutter Thanks for taking the time to reply, I truly appreciate it. I’m hoping to be discharged tomorrow.

[@Ryukachoo]

2 trillion years from now; the supergalaxy forms, all other galaxies are so red shifted even their gamma rays have wavelengths longer than the observable universe at that time. NINETY EIGHT TRILLION years later, star formation ends. We got plenty of party lights for a long time, folks

[@EvitoCruor]

lifesentence Shit? The metallicity of the universe will be much higher meaning a greater chance of planet formation and stars that fuse for a trillion or so years. Not counting the previous 97-102 trillion years. Even with immortality you'll be dead with near absolute certainty before you hit your first billionth birthday.

[@bobinthewest8559]

@Royal Freddy... I tend to think we will venture beyond our solar system within the next million years... If we haven't destroyed ourselves that is.

[@opsoc777]

What if the big bounce acts as a sorta clock in a giant universe or multi universe sized processor that big multiuniverse beings use over unimaginable timescales to calculate their big memes.

[@madcircle7311]

arthursday everyone

[@burns9281]

i like it but the sound of sutterursday not so much

[@dunn0r]

Arthursday, best day!

[@NicolasMarinos]

Happy Arthursday, my friend!

[@icantseethis]

Favourite day of the week.

[@isaacarthurSFIA]

'Sutterday' would work pretty well if Paul was doing Saturdays though :) But he releases more than weekly.

[@DrogoBaggins987]

Thanks for the wonderful pair of videos. I have a feeling that over the coming decades our understanding of the universe and how it will age will change a lot and really be refined. When we have a good understanding of dark matter and dark energy and a real model for how and when protons decay then we will be able to speak with confidence about the distant future.

[@PaulMSutter]

+Drogo Baggins I agree! It's so fascinating to me how much hinges on what dark energy will do. And to think that 100 years ago we didn't even know the universe evolved...

[@DinosaurEmperor84]

So the fate of life in the universe is far off death, a bit closer death or sudden death.

[@PaulMSutter]

+Dinosaur Emperor Basically, yeah.

[@bobinthewest8559]

Well... at least now we know...

[@dannyjbrigs]

Thanks Arthur for the channel referral, and great content to you Paul; subscribed.

[@PaulMSutter]

+Daniel Briggs Thanks so much, glad you enjoy!

[@saulw6270]

What if a boltzman brain is jus sitting alone in a universe quintillion of years in the future and life now is it thorizing the past

[@paulwalsh2344]

So, as I'm going to say in SFIA as well, we are most fortunate to live in the epoch that we CAN investigate and discern the nature and fate of the universe. As such fortunate intelligences, we owe it to cosmic posterity to compile, and if not exist long enough to teach to our descendants or the inevitable life-forms that will pop up and reach maturity during the end of the stelliferous era, then to archive and disseminate this information, bequeath it to future civilizations.

[@quailwatcher6798]

That sounds like a really neat sci-fi premise: an alien civilization nearing the end of time scours the remains of humanity to learn what the universe was like before.

[@jackvernian7779]

+Paul Walsh dare I disagree for the fact that we're not exactly sure if big bang was what started everything, it's just that we're able to see up to that point, but not beyond. So what if some lifeform formed in an isolated "megagalaxy", they would see redshift, and other laws of physics and prove them to be true, but they would not know what exactly awaits them or what happened before, same as we don't know right now. They most likely would know where approximately they came from, but less so, and they would also know how their observable universe would end. Same as us, they would not be able to look into the future of the past after a certain point, so to be quite honest, I think both us and they from the future are in a very similar informational bubble where there is no full certainty because our observable universe is limited.

[@hupekyser]

both great, fantastic content, love the more informational and scientific content, but Isaac's style of delivery is sooo fricken slick, and his voice is so great to listen to, I could just hear him speak all day.

[@MusiCaninesTheMusicalDogs]

This is so damn awesome! Two of my favorite KZbinrs together! I hope this collaboration will give your channel a so deserved boost, Paul! 👌👏👍

[@PaulMSutter]

+L Galicki Band Thanks, it was a fun collab to do!

[@bluepixelworks9302]

You need schooling for real.

[@jamesburleson1916]

Kinda makes me wonder how many cosmologists are nihilists. The existential angst this topic can bring about in people can get a little funny to me, everybody freaking out about the heat death of the universe or whichever bit they fear. It challenges the belief a lot of people have that their lives have measurable meaning in the universe. Personally I believe that the entirety of humanity is meaningless when viewed from the perspective of the universe as a whole, and people tell me I'm a depressing guy to be around, but I prefer to evaluate my existence based on that which I derive from my existence. Put another way, nihilists are right about believing that everything is futile, however they have also stopped seeing the beauty of the world around them. So while I am certain my life is meaningless, I can still enjoy the utter majesty of the universe and appreciate it's breathtaking beauty, be that at a macro or micro scale.

[@jackvernian7779]

+James Burleson too many people presume nihilism to be a negative thing. Done right, it does not get you depressed, on the contrary, it inspires you.

[@TerenceMichaelReeves]

Acknowledging a terminus does not in itself preclude a full and meaningful life.

[@utvara1]

the meaning of life, not your life but in fact all life, is to evolve to stop universal vacuum death life is universes attempt to fight the ever consuming nothing

[@jackvernian7779]

+utvara1 we can't stop death, and we can't stop heat death either. You can bend and pul laws of physics however you like, but you can't break them. Unless the system is fundamentally flawed and most likely our understanding of it is, as always, flawed.

[@utvara1]

Jack Vernian not with that attitude you cant

[@CarBENbased]

Happy Arthursday Dr. Sutter!

[@PaulMSutter]

+CarBENbased Thanks, I'm now aware that this is a thing!

[@ungoyone]

Came here from part 1. Didn't realize I traveled to a different channel. You guys are like, space wizards.

[@downsidebrian]

Came from Issac Arthur's channel. Heard "general relativity is simple," and thought, "I like this guy."

[@PaulMSutter]

+Brian Emerson it's simple, but not easy ;)

[@therearenoshortcuts9868]

if all that's left in the end is a blackhole, and the accelerating expansion will eventually rip stuff apart faster than the speed of light would the final blackhole also get ripped apart? (Before they even evaporate)

[@PaulMSutter]

+MGTOW Lawyer The black hole will remain stable until it evaporates.

[@coopergates9680]

@@PaulMSutter So dive into a SMBH just before the big rip? haha

[@piguyalamode164]

Well, the expansion of the universe seems to be constant

[@piguyalamode164]

Per unit distance

[@steriopticon2687]

As Peter Cook quotes Nesbitt in Beyond the Fringe, "...He ends on a note of hope, he says, 'I hope this doesn't happen.'".

[@12201185234]

I love this stuff. I'm glad you did this collaboration, since it helped me find your channel.

[@tamasmihaly1]

I've decided to watch all of Isaac's lessons over and over until I understand at least half of the material. It should take the better part of my life, I suppose. Well worth the time. I learn something new each time. You're the best, Isaac. Paul is a very appealing newcomer.

[@modulator7861]

Great episode guys! Questions: 1) How about Inflation Theory? Hypothetically, if Inflation Theory is true, as new/additional "space" is added to the Universe, wouldn't NEW/additional energy and matter ALSO be created/generated (as I imagine it, sort of "filling in the the stretch-marks" on our expanding balloon of a Universe? If so, wouldn't that mean it's self-populating" itself with new/additional materials for new star formation? 2) What effect does Zero Point energy (i.e. energy spontaneously popping in and out of existence) have on the data/energy/matter content of our current Universe? Is it so even/ balanced that it's irrelevant to any of the theories these guys have presented here?

[@ToyokaX]

Another great collab! Loving these, hope to see more from the both of you (and perhaps others!) :)

[@PaulMSutter]

+Toyoka Thanks, glad you liked it!

[@patches3432]

I absolutely love this kind of stuff, thank you guys for giving great content!

[@mikaeleriksson144]

How we understand the physics our universe as of now... I'm pretty sure we will look back at this sad gloomy doom video, probably in a couple of 100 years and snicker to ourselves... how little we understood and so recently, oh well... life goes on, and it will forever. HUMAN SUPREME!! :D

[@PaulMSutter]

+Mikael Eriksson Perhaps!

[@sohrabroozbahani4700]

OK, that just turned me on, already have a saga ready to launch and having thoughts about a second trilogy following that story line. i was planning to play with these end of the universe theories and that was such a great heads up on that subject. awesome job, thank you.

[@maracachucho8701]

I wonder what the effects of the accelerating expansion would be on black holes, specially big ones that won't evaporate as fast. Would it cause them to spew out their content? Would it slowly reduce their event horizon for hawking radiation to consume them?

[@IJustMadeAComment]

1-100 trillion years. I thought the weatherman was guessing when he said 0-120 degrees, now I’ve seen everything.

[@shaman444444]

We are part of the 4th dimension and we are just one of infinite scenarios of our Universe in the 4th dimension. So, whatever happens to this (Our Universe) already happened and only those from the 4th dimension can tell what happened. I just found your theories and it is helping me describe mine which I called it "Dimensional Universe Theories" hope to complete one day. I have been working on it forever and started to write it since 2009. Thanks for the help.

[@ravenlord4]

So if a civilization is born after the local group merger (and after the disappearance of the other galaxies), what conclusions could they draw about the nature of the universe once they got to our technological level?

[@mba321]

Not nearly as much as we could today. There should still be some faint, distant galaxies visible by powerful telescopes, but their civilization wouldn't be treated to the same menagerie of galaxies and clusters that we have in our sky today. It will be a great deal harder for them to draw the kinds of conclusions that we have been able to draw. To them, the entire universe would be the local group. Not much different than pre-industrial astronomy, in a way.

[@PaulMSutter]

+raven lord They could still end up discovering an expanding universe by mapping velocities of ejected stars, and calculate a rough age based on stellar metallicity, but that's it.

[@ravenlord4]

Thanks for the answers Michael and Paul. And I'm now a new sub brought over from Isaac's channel :)

[@TheOneWhoMightBe]

"... 120 trillion years from now, the last star will die." *existential crisis intensifies*

[@PaulMSutter]

I know, right?

[@ynkybomber]

I always thought we are in 1 universe floating in an ocean of other universes.

[@R.Instro]

Has anyone seriously considered the possibility of "The Big Rip" being a catalyst for a new "Big Bang?" Since we know that separating quarks from one another requires enough energy to bring new quark pairs into existence, shouldn't the Big Rip, once sufficiently intense to begin tearing quark pairs apart, provide a ready source of energy for the mass creation of new particles similar to what we expect from the Big Bang?

[@mven]

I don't think so. As I understand it, the Big Rip is what would happen to the universe if the observed expansion of spacetime never stops accelerating, to the point where the expansion outpaces the ability of fundamental forces to hold things together. First the expansion overcomes gravity at increasingly smaller scales - causing galaxies and solar systems to fly apart. Eventually the expansion overcomes even the strong nuclear force's ability to hold nuclei together. So the Big Rip isn't exerting any force to make this happen, it's just that the underlying spacetime eventually stretches faster than the fundamental forces can pull things back together.

[@saraeva]

I have also considered the Big Rip as an end state of this universe... I say 'this universe' because we don't know if there are others. However, in addition to separating quarks requires enough energy to do so, and also create other pairs of them, I also considered the effect of dark energy at the event horizons of black holes. Where dark energy is sufficient to rip quarks apart (thus creating new pairs), it should also affect Hawking radiation. Once a virtual pair of particles is created at the event horizon, and before annihilation occurs, dark energy would grab a hold of one, or both particles, thus creating new matter... and new energy (Einsteins equations of mass/energy equivalence).

[@MrGeneralPB]

iirc there was some youtube vids on it, based on some papers, think it was related to white holes, i cant remember from who or where... hope it helps, it has to be at least a few years old by now =/

[@glenecollins]

bigbenhoward if inflation is caused by gravity/ mass at long ranges? ;-p

[@timothycrystal2623]

What if the light from the closer galaxies was actually emitted more recently than the light from the more distant galaxies? A billion years ago, the galaxies were expanding at a given speed, and a million years ago they were at a slower speed... that somehow indicates that the expansion is increasing? How is this possible?

[@StopChangingUsernamesYouTube]

"And General Relativity is very simple[...]" Well, I guess I'm stuck here now.

[@PaulMSutter]

I like to keep things light and easy around here ;)

[@NexAlea]

The vacuum decay one is actually pretty terrific ... I love science for all the new nightmare you can get :D Now back to "The Simulation Hypothesis" video from Mr Isaac Arthur to complete my night-without-sleep. Anyway, great video, brought here by Part 1, always nice to discover a new channel, take this like, and this sub.

[@PaulMSutter]

Very cool, welcome aboard!

[@Deadsoc]

Really enjoyed your delivery and explanation of concepts, great video

[@braderickson9996]

Outstanding part 2. The big thoughts just keep coming. Now, another big thoughter(yes, I made that up) to investigate.

[@PaulMSutter]

+Brad Erickson totally stealing that word

[@s.wollberg4247]

Always love it when two of my favorite youtubers/podcasters collaborate like this. ^^b

[@PaulMSutter]

Glad you enjoyed it!

[@hokiturmix]

I love when Isaac talks about the end of times with our computer powers simulating endless universes with endless life with the power of a light bulb.

[@PaulMSutter]

I doubt that's realistic :)

[@mariokajin]

It certainly be interesting to be able to somehow harvest dark energy to get an overview of the ending of the future universe.

[@Jacob-yg7lz]

There's also conformal cyclic cosmology, where, if there's nothing left but massless radiation travelling at the speed of light, there would be no reference frame relative to eachother, so they would converge and cause another big bang.

[@sarcasmo57]

The universe tells the best jokes.

[@richhooker1263]

So glad I found your channel! Thank you for sharing

[@PaulMSutter]

Thank you, I appreciate it!

[@rebelbeammasterx8472]

If multiverse theory is right, and you can build a strong enough wormhole perhaps we could migrate to another universe??

[@scifirealism5943]

Correct

[@Jenab7]

Intelligent creatures that can do controlled hydrogen fusion, in possession of a gas giant planet of 100 Earth masses, can live for 1e20 years (with an average population of 1 billion) by siphoning and using its hydrogen as reactor fuel. They had better never lose the ability to do hydrogen fusion, however. Or its curtains.

[@Happymars24]

I'm going to sing the doom song now. Doom doom, doom doom doom.

[@Cybernatural]

So the answer to the Fermi Paradox is the study of vacuum decay. When a civilisation gets that far they accidently settle the local vacuum into a lower energy state from which point the end of the universe radiates from each of them.

[@BenieTheDragon]

20:47 "It's WAY far into the future" "Because you'll likely be long dead before it happens." which isn't any less depressing.

[@LA_Viking]

“Rinse and repeat!” I love it!

[@jackvernian7779]

I like your style of delivery more than Isaac's, you're quicker with explanation and overall more in-depth on the topics. Keep up the great work!

[@davidofmorris]

Why wouldn't we expect that distant objects would appear to be moving away more quickly because we're looking back in time to when the universe was expanding more quickly.

[@ChrisBrengel]

Wow! "Most stars to be born will live and die in a period when there was only one giant galaxy and no others to be seen beyond."

[@robo336]

Imagine if our universe is some gigantic alien who spilled a bucket of something and the acceleration of our universe is the contents of the bucket spreading out over the floor.

[@IABITVpresents]

the only feasible theory

[@atomiclemon77]

When you clean your chalkboard but it still looks dirty - awesome video :)

[@supershenron9162]

Somewhere between 1 and 100 trillion years?? I didn't realize we where talking about the cosmological cable man.

[@PaulMSutter]

Yeah welcome to cosmological predictions :)

[@RobinPillage.]

Great work guys! Subscribed Paul.

[@PaulMSutter]

Thank you!

[@mopnem]

Great job here guys.

[@PaulMSutter]

Thanks!

[@phoule76]

oh well, at least we got a postcard

[@PaulMSutter]

It's something!

[@silvadelshaladin]

It is always a major step forward when you have an argument between two factions of the scientific community and the answer comes back, "Congratulations, you're BOTH wrong!"

[@kensimmons9960]

If galaxies are moving apart, why are we going to collide with the Andromida?

[@PaulMSutter]

Galaxies more apart on average at large scales. Collisions can still happen.

[@horacecarter2081]

You cant make assumptions about stars not being born in the entire universe at a certain point when we cant even see the entire universe or even estimate its true size. We can only go by the observable universe and that is just a small speck.

[@PaulMSutter]

I'm talking about the observable universe.

[@lukemcniven4131]

Once the fundamental particles are each alone in a near zero energy state, doesn't that basically mean time has stopped? How can you have time without work being possible? All time can really be described as is things working on each other...

[@testblustacks5799]

I would like to know more about the Conformal Cyclic Cosmology model. Does this fit best with the big freeze or the big rip?

[@ariessweety8883]

I love ur videos and am so glad I have found u Mr. Sutter! Thanks to J.M. Godier (I hope I spelled that rite 😉) Also thanks to Mr. Issac Arthur whom both I ABSOLUTELY LOVE, LOVE LOVE!! Honestly I'm not sure why I haven't seen u b4 now since all I watch on YT is space science stuff (ok mostly) Anyhow I'm so glad to have found all 3 of u and I love all of u equally. I love learning about this stuff and I'm not smarter than ur average bear and so u guys make it really easy to understand. Sorry this is a book lol Please keep the videos coming, love the colabs, I'm now binge watching 😁😁 best of luck to all of u. Your really awesome ppl.

[@PaulMSutter]

Ha, glad you found me and enjoy my videos!

[@misterflibble6601]

My prediction: In the near or far future cosmologist will say everything we thought we new about the universe is wrong

[@lexington476]

Your chalkboard looks absolutely fantastic and factory new.

[@PaulMSutter]

Haha, thanks! It will get dirty enough soon...

[@colinmaclaughlanweir9670]

Cold dark and alone sounds nice

[@Volksjager277]

what about when you get to quarks? if i remember correct the amount of energy it takes to pull a pair of quarks apart makes more quarks. Could we have growing clouds of quarks or would expansion accelerate to the point that it could pull particles apart at the plenk length?

[@Ziplock9000]

Came here from Isaac Arthur's channel. Great content. Have a like and sub!

[@PaulMSutter]

Thanks, welcome aboard!

[@mikelfunderburk5912]

Welcome. I'm rewatching some of these. Always like seeing more people interested in science.

[@PeteofHartainia]

It seems like we shall all submit to the auspices of the King in Yellow.

[@atomiclemon77]

Sorry for the dumb question, but would a galaxy be outside of causal contact even with quantum tunnelling etc?

[@mrhamtastic3385]

So. Let's plan on our uploaded minds getting together for some virtual coffee in 10 billion years and see which one it looks like then?

[@rickpercy87]

Your thumbs bend back really far. Subscribed

[@zexks]

I didn’t see dark matter included in either part. Have to wonder how that will effect things just as much as dark energy.

[@ynkybomber]

When Isaac says sub I sub. :)

[@anthonyrsullivan]

Not sure if you have covered this topic but maybe u could do a video on stellar encounters and different stars that have passed by us or will pass nearby in the future? Seems an interesting topic.

[@stefanr8232]

Is that a remnant at 5:14? I thought type 1a SN did not leave one.

[@RJL738]

Thank you for explaining this.

[@PaulMSutter]

+RJL738 You're welcome!

[@oonmm]

I just beat Bayonetta in 2 days! I have never been so hooked on something that I have to do it all the time till it's all done.

[@TDQ_Gaming]

If E=mc Squared defines our causal bubble maybe the speed of light isn't a constant and dark energy isn't an "energy" but it's an equilibrium that's more a property of space time and the amount matter that is disappearing from the casual bubble is roughly equal to the amount of matter spontaneously created.

[@ColonelEviscerator]

The Degenerate Era. In more ways than one!

[@smorrow]

In which white dwarves become more like black dwarves.

[@robinhyperlord9053]

Dark Helmet!

[@Jai_Lopez]

Great video collaboration Paul & Isaac, i think a video talking about what will happened to these galaxies that are the most furthest out in this expansion? as one day i supposed it will be our turn although by then i doubt we will be living in planet Earth but its worth a shot as it will bring in ears as this topic i doubt it has been brought out by anyone and most certainly not by your guys!

[@PaulMSutter]

+Jai Lopez this has already happened! It's all a matter of perspective. To distant galaxies, we are the ones receding from view.

[@achtsekundenfurz7876]

Just one nitpick: Paul, you managed to misspell "compenium". (check Isaac's part 1) ;)

[@RuthBingham]

When people think about the subatomic particles being pulled apart by inflation, nobody seems to consider the particles that are made of quark pairs. Is my info on the behavior of quark pairs out of date? I always thought that, when you pull a quark pair apart, you don't get individual quarks - you get two quark pairs. All the energy of pulling them apart has transformed into new matter. So I imagine starting with one quark pair being pulled apart, then there are two, then 4, then 8, then 16....exponential creation of new matter out of the inflation energy. To my mind, this could be how Penrose cycles work.

[@JB-ym4up]

No offense to Paul but I've grown accustomed to Issac's distinctive voice and now listening to space stuff without it just doesn't sound right anymore. Nice collaboration.

[@MrWorld-hc5rs]

mind blown.

[@jonathanhensley6141]

Awesome collaboration and i wonder what the origin of dark matter and energy is. Wonder if its outside the observable universe or another dimension. The timeline is like in the last question.

[@JohnBoen]

I consider the fate of the galaxy when a razor ad comes on... Hmmm.

[@petrino]

WHY IS THERE A FACE? isaac never has a face. he has pretty pictures.

[@robinchesterfield42]

For anybody feeling bummed out by the dark, cold, lonely nothingness of the stars all dying off...now go watch Isaac Arthur's Black Hole Farming and Iron Stars videos. :D

[@chromabotia]

I'll admit, this has been a pretty good gloss of future possibilities. What about branes though? And folks, if you like this, try "A Universe from Nothing" by Lawrence Krauss it is a good read. Remember that if one invokes quantum field theory and quantum mechanics in general - and one waits forever, literally anything will happen.

[@enlightedjedi]

All of that assuming a "natural" development. But assuming future us or similar will be around., and I think it is a pretty safe assumption we could have tech to change many of those, although I can't imagine how we would "master" dark energy.

[@IABITVpresents]

It could be either some fifth force or not even exist (some calculations need to be rewritten in that case).

[@bradhaaf4749]

I've always thought of our universe as a stick of dynamite thrown into a lake, it goes boom and for a second there is a "universe" within the lake but eventually the force of the bang will exhaust it's energy and whatever was there before will rush back into the void. What i think of dark energy, the water rushing back in after the bang filling the gaps and forcing the pieces of the bang apart. What theory does that fall under ?

[@sizur]

If you approach c, would distance contraction expand our universe horizon making lost galaxies reappear even to the point of us reaching galaxies that went way past the horizon?

[@rJaune]

I heard that when you try to pull quarks apart it actually just makes 2 sets of quarks. So what happens when Dark Energy tries to rip apart protons and neutrons?

[@johnharbinger4637]

forgets about bubble areas of space that are now going faster than light would be going backwards in time. So excelleration of space would create a big crunch through time aka A Time Loop that is however still moving forward in time as per the perspective of any matter within those bubbles of space.

[@firejuggler31]

Is it plausible that humans (or whatever exists at the time) could add or remove dark energy from the universe, thus choosing its fate? Is dark energy subject to conservation of energy?

[@robinhyperlord9053]

Try and implode the Universe to harvest its remaining energy then escape to the Multiverse for infinity.

[@GrandpasPlace]

So the galaxies in the local group collapse into a single galaxy with a supermassive black hole at the center that is the collection of all black holes in the local group. The galaxy then eventually cools and falling into the black hole, the black hole cools and evaporates due to hawking radiation. Leaving a naked singularity. A naked singularity is not stable on it's own and thus explodes in a big bang. ;) Just an idea. lol Personally, the bit I never got was dark energy. If you imagine the universe as a bubble expanding into the foam of the multiverse. Like a balloon that is expanding in a vacuum, then from inside the balloon you would perceive a energy pushing the universe apart when really it is a pressure differential and not energy inside the balloon. I have always perceived dark energy as an energy differential between the universe and the foam of the multiverse. It is the foam of the multiverse that is pulling the universe and causing the expansion.