Existential physics: answering life's biggest questions - with Sabine Hossenfelder

Do we have free will? Is the universe compatible with God? Do we live in a computer simulation? Does the universe think?

In this talk, Sabine explores counterintuitive insights, and interviews with other leading scientists, to reshape your understanding of science and the limits of what we can know.

This talk was filmed at the Ri on 19 August 2022

0:00 Introduction - what is existential physics?
3:54 Does the past still exist?
9:55 The block universe
11:40 Can information be destroyed?
16:42 The measurement problem
17:27 Black hole evaporation
21:20 How did the universe begin?
29:17 Are we part of a multiverse?
34:53 Can particles think?

Sabine Hossenfelder is a physicist and science writer.

Sabine is currently a research fellow at the Frankfurt Institute for Advanced Studies. Sabine's research focuses on the foundations of physics, but her interests extend to the philosophy and sociology of science.

Sabine partly works as science writer. Her writing has been published, among others, in 'Scientific American', 'New Scientist', 'Nautilus', 'Aeon', and the 'New York Times'. Sabine has an active YouTube Channel dedicated to communicating current science news and scientific methods in general.

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[TimBitts]

Sabine is a gem. The kind of teacher we all wish we had.

[BonsaiBurner]

For an intellectual, Sabine always comes off as intellectually honest and having a "real" conversation. This is refreshing and appreciated in an ever polarized world.

[lrvogt]

I really appreciate how Ms Hossenfelder insists on what we don't know or can't know... yet.
Her YouTube videos are excellent

[davidpantoja]

Just love that I can watch content like this at my leisure.

[captainoates]

Sabine. I am in awe of you trying to cover most of what I have learned over several years of watching your videos in one go to an audience. Your communication skills no no bound.

[gefginn]

Sabine has a great gift for delivery of tough topics. A great teacher.

[iv]

As a former physics student I find Sabine's videos refreshing. I can recall when I first learned about a concept and why I still find it interesting, basic curiosity about the world. What I find most amazing is that the physical laws haven't changed as much as we have. I am an entirely different person today than the kid who liked reading about new particles and worm-holes at the library after school. Then I dreamed of discovering something that would change the world, now I am not sure technology is really the right means to do it. Science can tell us what we can do and how to do it, but not if or why. It is important to understand where we live and what we are made from, what is time...etc. But a more important question for me now is, what is consciousness, its function and how does it fit with what is being observed? I would like to see more on this....many "big" scientists have contemplated these questions, even without a theory or proof. Yes, That guy again : ) Sabine, you have a crush on Einstain!

[needheartranken]

Everytime I get crazy contemplating about what reality is really, I look at Sabine's videos and gets calmed. Thank you, Sabine. My existential crisis saviour! We DON'T KNOW, and I think that's enough. Living as a human in the blip of time is an amazing ride!

[MandoDan]

Much thanks to Sabine. Big concepts translated to an easy to understand, honest presentation about what our collective observations teach us. (And clarity about what they don't).

[arasharfa]

Sabine is so extremely clear in describing complexities, i love her lecturing style.

[wacomtexas]

Thank you Sabine for a great talk, and for reminding us that what we don't understand is as important as what we think we understand..

[michaelhunter]

I like simple stand-up presentations like this rather than videos with sound effects and flashy video editing. This was a special treat for me.

[crowlsyong]

You and Matt O'Dowd are keepin it real for us all. Thank you.

[davidkent]

Why is intellectual honesty so rare? Thank you, Sabine

[spirosmatthaios]

Sabine is always impressive and inspiring! Allways to the point and "down to earth" despite being an astrophysicist!

[edwemail]

Thank you RI for bringing us a great lecture from Dr. Hossenfelder.

[plasmaburndeath]

OMG I am so excited that Sabine got to be in person lecture 😀 I discovered her work and her YouTube Channel a few weeks ago and now she is popping up everywhere heh.

[AlexanderWerner]

Sabine talking at the RI. Like Christmas and Birthday at the same day! Superb!

[rayoflight]

Congratulations Dr. Hossenfelder for the great intervention!

[carlosalbertoteixeira]

How great to see you here, dear Sabine! Grüß dich from Niterói, Rio de Janeiro, Brasil!