Multiverse or Cyclic Universe ? Alan Guth vs Roger Penrose

Do we live in a multiverses or a cyclic universe? Most cosmologists today accept the universe underwent a very rapid period of expansion called inflation. But inflation seems to lead to an infinite multiverse. Not everyone is happy with this multiverse ; and some cosmologists have sought alternatives to inflation. These alternative schemes are often cyclic. The chief proponent of one such cyclic model is 2020 Nobel Prize Winner Sir Roger Penrose. In this video the father of inflation Alan Guth and Sir Roger discuss the pros and cons of the inflationary multiverse versus Sir Roger's Conformal Cyclic Universe.
We highly recommend watching our film on eternal inflation with Alan Guth and colleagues
and our film on CCC with Roger Penrose and colleagues
and other films in our Before the Big Bang Series which features Stephen Hawking, Alex Vilenkin and others.

[miacrowell]

Fabulous content.. great job. Perfect moderation and what sterling guests. Thank you for this delicious treat.

[albat]

Such a spectacular discussion featuring two legendary scientists! The arguments from both sides were so sharp that I had a feeling that I was watching a thriller. And the moderation was top-notch, with concise and precise comments done at the right time to allow for a less prepared audience to follow the discussion. Have never seen anything better in many years. Great thanks to everybody who made this event for us.

[moftan]

Absolutely the best cosmological discussion that I've seen in the last 10-15 years. At least from a CCC perspective which is what interests me most. Thank you so much for expertly moderating this in such an informed and entertaining way! And thank you to Prof.s Guth and Penrose for such a good natured, friendly and illuminating discussion! Truly wonderful experience up listen to this!

[sswwooppee]

Both Guth and Penrose are such heavyweights. I have nothing but respect for both of them. I really enjoyed this conversation.

[enricodirocco]

Penrose is the greatest mind of our time

[JrobAlmighty]

Absolutely love a good well intentioned debate without nonsense argued in good faith.

[akumar]

Oh my word this is unbelievable Guth and Penrose together, this is wonderful, I shall cherish this video and listen to this over and over again .

[quantumcat]

Alan Guth and Sir Roger Penrose are two giants! Listening to them, exposing their thought about the "immensity", is like listening to music to me. It elicit so much fascinating ideas. Can't have enough of that stuff. Thanks for this wonderful piece. Merci beaucoup!

[illogicmath]

The moderator's work is truly commendable

[rickcygnusx]

Wow!!! I'm speechless! This episode is too important to be on You Tube!!
I think Alan and Roger should definitely get together and collaborate on analyzing the CMB data a little better. They should even write a paper presenting their results

[patekswiss]

Every few weeks we seem to get some over the top hype about some boxing or MMA prize fight. Now, THIS is a prize fight! We’ve heard all the smack talking, now let’s see who has the goods. Seriously, thanks so much for this momentous video, to you and your participants.

[leighedwards]

Great stuff - I'm so glad that this debate took place. Both Roger and Alan were firm, but gracious, in presenting their respective arguments and very well moderated by Phil too.

[coniferviveur]

This discussion was a captivating intellectual delight, enhanced by the intelligent and pertinent contributions of the moderator.

[scottahunt]

What an engaging and respectful discussion of competing ideas by two brilliant thinkers. And a superb job by the moderator. This was a joy to watch. Thank you for your hard work to make this happen.

[tommylakindasorta]

I respect Penrose and his team for going up against the establishment on this, regardless of whether their conjecture turns out to be correct. The one issue I have is that, according to this interview, the primary problem with inflation that CCC seeks to solve is, according to inflation, not actually a problem.

[throwabrick]

Bless Roger Penrose! He is a personal hero and I cherish all the crazy things he says. I am a huge fan of CCC and ORCH O-R theories: even if they will be proven wrong they are courageous attempts at solving BIG problems that are grounded in solid math and that is what we need more of.

[Rossion]

Magnificent. I get the feeling that Sir Roger is much closer to the truth.

[TheDrakmannen]

Clicked this literally seconds after I saw this in my feed. GOAT of science videos managing to get Alan Guth AND Roger Penrose at the same time. Kudos!

[tokiamsterdam]

This is why I love YouTube. A true clash of the titans. I thoroughly enjoyed this. Thank you.

[maxidejf]

What an absolute delight to be able to listen to this discussion! Thanks to all involved!