Bennett and Deutsch: The Nature of Computation, Incompleteness and Mathematics

In this conversation with Charles Bennett and David Deutsch, we delve into the nature of computation, incompleteness and mathematics. The discussion also touches on cosmology, the anthropic principle, the arrow of time, Boltzmann brains, high-level fundamental laws, AGI, probabilities, and quantum theory.

[thomasseptimius]

David Deutsch ability to create complete breakdown in colleagues understanding of the world only to slowly but confidently walk them through a rebuild of their world view to get them almost excited is amazing to watch.

[itsphysicsterry]

"I'm certainly not a mathematician, thems fightin' words" LOL

[isaacsaxton-knight]

I want Deutsch to make series after series of video explaining this, and more books

[kcltegu]

Thanks, Charles, fantastic discussion!

[krimdelko]

If the laws of physics are the ultimate arbiter between what is and what isn’t, can human ingenuity and/or creativity change them? Is that possible in principle? Who is the ultimate arbiter?

[FAAMS]

Just a couple of notes:
I have problems with the concepts of emergence, with the concept of creativity and even with the concept of Infinity. They all invoke IMO some form of magic conjuring! Now I am not a mathematician, not a physicist, not even a formal philosopher...I just think very hard about the meaning of words and try to stretch concepts to their breaking point to see what comes out.
Back on track my objection to emergence is related with another obscure concept which somewhat states Nothingness is somewhat a form of something, the empty set, and other similar definitions, but that inevitably are always relative to stuff that exists, so no absolute nothingness can be derived. And on this regard I invoke Parmenides to the problem. There is nothing to Nothingness, that simple!...non being has no properties. Nothingness is ultimately a self refuting concept, the absence of absence!
Now on my reasoning it follows that everything that can be in the future IS already as all space of Being, all that is possible "physically" has to be complete, and this fits well with the idea that time is relative, the idea of a block Universe is timeless. Also intriguing phenomenologically speaking the idea of retro causation would throw away the idea of emergence which sounds like magic when we look at it bottom up instead of top down. I rather start with maximum complexity, the set of the most things that can be correlated as "computed" or "constructed" and go down instead of going up...of course in a timeless block Universe this is just a phenomenological illusion, a mode of explanation...retro causation explains away emergence, and the idea of an expanding Universe into Nothingness, which makes no sense. But ultimately retro causation is just another form of bringing time and motion back into the equation, which is not compatible with a true block Universe. Regarding Infinity there is a distinction to be made between qualitative infinity (news) and quantitative infinity, which can be boundless but brings no new qualitative information, no new phenomena to perception, thus enter fractal patterns that do no halt but that do not inform anything infinitely new either...Fractals are informational finite but do not halt when you run them. My final point is that I am willing to put up with a very boring qualitatively finite Universe that does not halt but repeats in cycles just to stop magic conjuring being allowed in Science linguistic parlance. Fast and loose with obscure concepts is really really annoying!

[ptaylor]

You can really see the psychological struggle with infinity at certain points here.

[TechyBen]

Very good. However pi appears else where in math, the "mathematical pi". It's a "real" thing, not geometry dependent. Ah, you did mention that.

[ashikpanigrahi]

I wonder why David said that consciousness Must be a Physical process..? Doesn’t that already assume physicalism to be true?

[tarikozkanli]

Infinity is the surface concept in which universe exposes one of it's properties.