What We Cannot Know - with Marcus du Sautoy

Is it possible that we will one day know everything? Or are there fields of research that will always lie beyond the bounds of human comprehension? Marcus du Sautoy investigates.

Is it possible that we will one day know everything? Or are there fields of research that will always lie beyond the bounds of human comprehension? Former Christmas Lecturer Marcus du Sautoy will lead us on a thought-provoking expedition to the furthest reaches of modern science.

Marcus du Sautoy is a mathematician and popular science writer and speaker. He delivered the 2006 CHRISTMAS LECTURES on mathematics, titled THE NUM8ER MY5TERIES. He is currently the Charles Simonyi Professor for the Public Understanding of Science at the Oxford University.

This talk and Q&A was filmed at the Ri on 13 October 2016.

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[youtoober]

18:18
"Ah... so I mean where did that come from?! _Unbelievable!"_
-Pure joy.

[ratsukutsi]

I absolutely love this guy. The pendulum example was an event on itself

[DavidMcCoul]

13:25 Chaos theory: Predicting the future
28:00 Quantum mechanics: Heisenberg uncertainty
39:14 Quantum cosmology: The origin of the universe
43:12 Quantum physics: The "smallest" particles
44:12 Astronomy: Seeing past the observable universe
45:36 Cosmology: Time and events before the Big Bang
46:44 Neuroscience: The origin and definition of consciousness

If the "Theory of Everything" (M-Theory or similar) can ever be confirmed and completed (even if by indirect observation), then we may have insight into all of the above on some level. For example, Heisenberg uncertainty, quantum fluctuations/gravity/cosmology, the source of the fundamental particles, and even events before the Big Bang may all be more knowable from this unified theory. Chaos theory may also depend on quantum fluctuations. Even consciousness may arise from quantum effects since neurotransmitters are close to the de Broglie wavelength.

Also, we could see past the observable universe if we could build a telescope with a warp drive. This is something that is theoretically possible, but is practically impossible due to the present inability to generate gravitational waves. However, a unified theory could help us understand more about gravity as well.

While highly speculative, all the above may actually be potentially knowable, at least in part. I think it would have been interesting to discuss NP complexity as well as Gödel's incompleteness theorem that he references at 46:15. While more abstract, these two topics more conclusively show what cannot be known given a certain approach.

[macrovigilance]

he's my favourite on the stand-up science circuit!

[cripmeister]

This video holds the record of "largest number of words spoken in under an hour" on youtube

[yereverluvinuncleber]

Does infinite amounts of coffee give infinite amounts of energy? Marcus seems to have tried to test this theory...

[nihil]

His role in "the code" was a perspective altering experience for me. Marcus's insights sparked my desire for mathematics and by extension my will to persist. For that, I'm grateful for his contributions.

[erictaylor]

In the 1980's we knew that the universe was expanding. We knew that we did not know the rate at witch the expansion of the universe was slowing. We did not know that we did not know why the the expansion rate of the universe was accelerating.
In the 1990's, in an effort to measure the rate at which the expansion of the universe was slowing we made the astonishing discovery that it was not slowing at all, it was accelerating.
In an effort to discover something we knew we did not know, we discovered something we did not even know to ask about.

[bikashthapa]

i love the way he is excited about science thanks man you are inspiration to me

[DavoidJohnson]

What better way to explain chaos than to have a seriously chaotic person to present it.

[myronww]

There is a theorom that answers this: If something can be known, then there must exist a series of questions that if asked and answered, can get you from what is currently known to what one wants to know.

This is pretty significant because it means you just have to be able to:

1. Find and ask a question that will get you closer to the answer and can be answered in sufficient time with an affordable amount of resources.
2. Continue to perform step 1

Eventually, you will bridge the gap from what was originally known to what you started off wanting to know.

[imnogrejones]

I work in a casino. If my boss sees that pendulum it will be the newest Roulette game.

[katestevenson]

form is emptiness ~ emptiness is form ♡ love all these videos, makes me so glad I am a Buddhist, so grateful for l this life ♢

[ReginavariedintrC]

I love listenignto the ri lectures used to watch them when very young now 48 not a scientist and still enjoythem. ;-)

[josfitz]

I loved when he was explaining how we might know which side the dice would show and it unexpectedly flew right off the desk.

[gbear]

The human experience is that we can imagine. So much of what we know came from trying to explain what we observe.

[mollanoori]

Watch with 0.75x speed to sound normal!

[Roedygr]

This guy is a hoot. He is funny. He knows his science. He talks about things you have not heard a thousand times before.
Highly recommended!

[bazsnell]

Always good to see Marcus giving a lecture. Never ever disappointing.

[DrJeeps]

I've now watched the same lecture nine months later still fascinating!