The End of the Universe - with Geraint Lewis

Come with us on a very final journey as we wander forwards in time at breakneck speeds to see what happens at the very end of the universe.

Will there forever be stars in the sky? Will humanity roam the cosmos for eternity? What does the future hold for our Universe? This is a journey through space and time, from galactic collisions and hyperactive black holes, on to the death of the last star.

This talk and Q&A was filmed in the Ri on 24 July 2018.

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[huhuruz]

I was asleep and this video appeared on my list and I gave it a Play ... I enjoyed every second and now I can't sleep. I think of everything Mr. Geraint Lewis said ! I learned a lot tonight.
Thank you very much !

[Saleemsan]

Oh, and Ri, since my kids were little, we've been listening to all these wonderful Ri talks, and now they are teenagers, and still like them, as do I

[afterthedrjay]

So glad the audience wasn't interrupting Mr. Lewis' presentation. They were actually listening to him and the concepts he presented. The Douglas Adams line was a great thought provoking ending. I loved this presentation and the speaker.

[tappajavittu]

To everyone who enjoyed this lecture and doesn't know about Geraint Lewis' and Luke Barnes' youtube channel Alas Lewis & Barnes, I'd highly recommend it for anyone interested in cosmology, good stuff!

[vin]

not just gorgeous ( a real silver fox!), not just gorgeous AND intelligent, not just gorgeous, intelligent AND a superb communicator - but gorgeous, intelligent, a superb communicator, AND Welsh! A quadruple whammy....what a joy to find this series.

[rahulgosavi]

Being an enthusiast since the age of 6 and now watching this, makes me want to leave my digital marketing job and study cosmology full-time. I wish life were that easy.

[markiliff]

Why haven't I heard of Lewis before?! This was beautifully clear, nicely constructed and delivered with just the right amount of dry humour.

Oh, and I read Black Cloud 50 years ago and hadn't thought about it until last week. Now here it is again. Miraculous.

[boxelder]

This was so encouraging. Finally I got the assurance that I needed that eventually all my enemies will be dead and I won’t have to ever pay taxes again or listen to politicians give non-answers to the people that they were hired to represent. Ahhhh! Peace at last.

[pampa]

beautifully communicated, I enjoyed this lecture very much!! Thanks to the RI for putting on these lectures, and thank you to Geraint Lewis for a great talk!

[celestialaeonproject]

Thank you for posting this, an excellent presentation! This is one of my favourite subjects as it really resonates with the human condition and wonder, what are we supposed to do with our time here? I think it is quite safe to say that either one accepts that whatever we do "here" doesn't really matter that much because of what was presented here, or one states that the only meaningful thing to aim for is to at least try to go as far as we can in this puzzle that is the Universe. Which would basically mean going forward on Kardashev scale and just try work out the physics until we truly understand everything there is.

Whichever way we go, i think most of the stuff we humans spend our time and effort currently on which is basically more or less tribal warfare and squabbles regarding who gets what back from somebody else who took the stuff back in the day and eventually will lose it again is something we should just stop. We are acting like a spoiled brat and we should grow up, because there is the heat death of the Universe that awaits us.

[Dss-bmrz]

I can't get enough of these intellectual conversations, it's the one thing that actually stimulates my mind and gets my neurotransmitters pumping. Thank you guys.

[brianhubis]

This one is so good, my favorite so far. I will actually watch this one more than once.

[steveirons]

Thank you Geraint Lewis for expressing ideas that I have had myself, & you express them with such clarity & give me so much by doing that. The final theme suggesting that it could be that the big bang has all happened before & could be a recurring moment in an overall universal "tiem-line" going on forever is one that I have been going on about to my friends for decades. They go "whatever". But it makes a lot of sense to me, although many will expect any expression relating to it to be accompanied by the scientific opt-out "we just don't know". Recently I have been listening to other addresses in this TRI series & in doing so a thought crossed my mind (mainly when listening to David Tong on field theory, which is given more definition by Harry Cliff's address on the Higgs boson) that there may well be, in this new strong acceptable/accepted definition of fields, an underlying explanation of Hubble's continuous expansion of the universe that you refer to that might just bring it all together. I am not a scientist & so not in a position to express this idea in any acceptable scientific form, & it may make little sense to those working in physics but 'll express it anyway. Who knows, there may be some benefit in doing that. It goes like this: There is only one independent force in the universe, the force of gravity. The rest are dependent forces, dependent upon the big bang. The energy available to be played out in the "life" of the universe that you describe, all exists at the moment of the big bang. Tong & Cliff give us the Standard Model. This is suggesting that the cosmic energy field is what exists after the whole thing settles down, and what you are left with, what is left over after matter versus antimatter has annihilated itself, the subsequent electromagnetic forces, the strong nuclear force, the weak nuclear force, the Higgs field that gives rise to mass, electrons, protons, etc. energy itself is there as a temporary adjustment to the failure of matter to completely be annihilated by antimatter. Harry Cliff showed us a picture of "what the universe should look like" applying the Standard Model and it looks extremely similar if not identical to the "end of the universe" you describe, the only difference being space and time. If it were possible to have a "clean annihilation" in the first few hundred thousand years after the big bang, he says, that's what it would look like. So the clouds, the galaxies, the suns, the planets, etc. are simply an expression of the uncertainty principle, proven to be correct by elements making up the background radiation in Tong's talk, not long after the big bang, that such a clean annihilation is never gunna happen. The universe is simply an expression of that; what is left over is fundamentally unstable; energy is the movement from "unstable" in the present to "stable" in the end of time that you describe. The process you describe, which is a picture of the "life" of the universe along the way, gives Cliff what he is hanging out for, "in the end". The "fields" described by Tong & Cliff are created by that process of movement from unstable to nothing. The uncertainty, the instability, the energy, "creating the fields", is responsible for everything in the universe, except for the force of gravity. It is responsible for the gas, the particles, their separation, the clustering you describe, their creation of suns, of galaxies, their burning, hydrogen, helium, their emission, photons, for their turning into red giants, into dwarfs, for dark matter, for the expansion of the universe, everything, You describe clearly the "end of life". But when the "life" of the universe has ended, what are we left with? You seem to be describing everything moving away from everything else at the speed of light, dark energy, the force of repulsion, is now everything, and it is also nothing because there is nothing to repulse. Because the big bang exists, the universe only exists because of the expansion of the universe. Take that away and everything is turning in on itself. When dark energy is universal, the expansion is ended, the only force available is the force of gravity. This means that the disarray within the repulsion caused by the history of the universe leads to clusterfuck, the clustering of dead/dark matter. The force of gravity may be weak, but it is the only force in the end. It brings all this matter back together again, setting up the ideal conditions for another big bang. Because we see no evidence for the creation of the universe, & because the universe exists at all, we know that the big bangs have been happening forever. And because of this, we know that the idea that a big bang at some "tiem" in the future will lead to complete annihilation is a nonsensical idea. It could happen, but because uncertainty has reigned supreme, forever, up until the present, it is highly unlikely in the future.

[bigpompano]

It hurt me each time they didn’t laugh at his little jokes lol

[davidbrown]

I wasn't worried about what I'm what I was going to do ten billion years from now till I watched this show.

[danielschaeffer]

I'm reminded of the Peter Cook line. "Still, there is hope. I hope this will not happen."

[maximuscomfort]

Never tire of these talks, Thank you.

[dadsmidnightcreation]

outstanding lecture. I have learnt so much from this guy in the last hour than I did all the way through school. wow I actually feel more clever than I did an hour ago :)

[thekingofmojacar]

Nice lecture, thank you The Royal...
Life is an expression of the universe, a part that has to do with existence, consciousness and nature. Stars and galaxies and all other celestial bodies and sometimes structures also have their existence and their cycles, everything lives and moves. And so one can say that this constant movement of everything (in the whole universe, at least in this one in which we are currently located) is an expression of life and existence... 🌞

[davidsavage]

So well-spoken and a pleasant conveyance of complicated information, with great graphics.