Riffing on Karl Popper and David Deutsch (especially). A broad overview, covering lots of the basics of "social" or "rational" choice theory, Bayesianism (again!), misconceptions, good ideas and bad. Errors my own as always.

Here we explore the distinction between classical notions of time (including spacetime physics) as approximations to how time is understood in the multiverse. How perfectly deterministic laws lead to subjective unpredictability. Consequences for free will, questions about what happened before time began (or after it ends), new discoveries since the publication of The Fabric of Reality was published in 1997 and David's subtle alterations to phrasing between The Fabric of Reality and The Beginning of Infinity (in particular with reference to identical vs fungible and how tossing "fair" coins in our universe isn't 50/50 heads and tails. If you would like to discuss any of the content in this video with me at length, sign up to Airchat at https://www.air.chat where I am active daily answering people's questions and engaging with those interested in the work of David Deutsch and associated thinkers and ideas explored in his work, wider physics, philosophy and everything.

If you are distracted by, or simply prefer a version without, the background music - you can find that here: https://youtu.be/xSbqTTs1nl0

My preferred version is here: https://youtu.be/2IneL4VpShE as there are some helpful (though not essential) visuals.

This is about knowledge creation and the the commonalities between the two forms known (evolution (by natural selection) and explanatory) and the differences between them. It teases out and synthesises some of the work of Darwin, Popper and Deutsch on these matters of what creativity means. I also consider the place of prediction and prophecy and the "urge" to know what the future will hold. This is sometimes the dividing line between optimism and pessimism.

You can support this ongoing exercise in optimism, exposition and encouraging rapid progress by following the links here: https://www.bretthall.org/ Thankyou for any and all support. Know it is much appreciated.

Sam Kuypers is a theoretical physicist who specialises in the physics of time. If you have the time, Sam can take up as much of it as you like telling you about how our ideas of time have changed…over time. As Sam will reveals: times, they are not a-changing. But there is change! Newtonian physics has a notion of time (or at least Newton himself did), Relativity as discovered by Einstein in the early 1900s radically transformed our notion of what time is and now, in the 21st Century, Sam Kuypers and others are beginning to develop a quantum theory of time. And this is why Sam joins me for this episode as we unpack time as a quantum concept: the very topic of Chapter 11 of “The Fabric of Reality” and go deep on Sam’s more recent contributions to our understanding of the reality of time. Appropriately, time stamps are below.

You may have to take your time with some of this.

00:00 - Introduction to this episode

05:04 - Introduction to Sam Kuypers

06:30 - The day-to-day of a theoretical physicist

10:30 - What led Sam to Oxford University

12:10 - What was Sam’s doctoral thesis about?

15:20 - The importance of Everett

16:30 - “Classical” Time and “universal time”.

27:00 - Julian Barbour and time as a series of instants

30:35 - Spacetime and the timeless view of physical reality.

33:35 - The clash of General Relativity and Quantum Theory I

37:20 - The clash of General Relativity and Quantum Theory II

40:40 - c-numbers and q-numbers

42:30 - The significance of (non) commutability (i.e the Heisenberg Uncertainty Principle).

46:05 - The Page-Wooters Construction (Quantum Time I).

53:15 - Can there be change if nothing is ever changing? (Quantum Time II)

55:31 - The Heisenberg vs Schrödinger “Pictures” of Quantum Theory.

57:35 - What is “locality” in physics?

58:40 - Entanglement and: "Does Quantum Theory allows for faster than light communication?” 

1:00:48 - Unitary Quantum Theory (vs: Everettian Quantum Theory)

1:05:33 - Philosophical Realism, Physics

1:06:40 - Does Time Exist?

1:07:58 - Is Time Travel Possible?

1:11:30 - How did Sam find his way into physics?

1:14:30 - The Dutch Enlightenment vs The British Enlightenment

1:20:50 - The Netherlands, international trade, tolerance and specialisation

1:23:08 - The Invention of Free Trade and misconceptions with long lifetimes.

1:16:30 - The peculiar rivalry between European Allies

1:28:40 - Prosperity and Pessimism: Are both on the ascendency?

1:32:19: Why are people special?

1:37:14: Liberalism, Authoritarianism and Climate Change

1:40:25: Science, Morality and (eg: Dutch) Innovation

1:43:30 - Concluding Remarks 

Part 2: Time is in the instant. The instant is not in time. More on the quantum theory of time and how the "spacetime" view of time, and the flow of time are false. How time relates to the "block universe" model and how the multiverse fixes the paradoxes at the heart of our common sense (and classical physics) ideas about time - more readings from "The Fabric of Reality" chapter 11 and in addition:

A couple of acrostics about David Deutsch in terms of "Popper".

David's changing view of free will.

Readings on "free will" from "A Science of Can and Can't" by Chiara Marletto.

A summary of a paper by Marletto and Vedral on the "Page and Wooters" construction.

Brief remarks on Marietto's "Constructor Theory of Thermodynamics"

Kuyper's thesis "Developments in Unitary Quantum Theory"

The paradoxes involved in trying to picture time using diagrams.

Machian Dynamics (Ernst Mach's idea about absolute space and time being false and instead how the universe has dynamics of its own).

The Schrödinger vs Heisenberg Pictures

The Kuypers and Deutsch paper on "Everettian Relative States in the Heisenberg picture"

"And other topics" as Sam Harris says. Reference: Mentions of Sam Kuypers paper on "q number time" throughout: https://royalsocietypublishing.org/doi/full/10.1098/rspa.2021.0970

This is really "episode 0" but not quite because we do indeed get to some readings and unpackings of the chapter. But in the overall scheme, that forms a minor part of a longer introduction to the "common sense" understanding of time and then to some relativity (of simultaneity) and reflections on the work of other physicists and popularisers.

Note clips from "The Lord of the Rings" and "Spaceballs" movies are owned by their respective copyright holders.

Some more long introductory remarks and commentary throughout readings of the closing pages of the chapter culminating in the explanation of the "punchline" conclusion of the chapter which is: "Necessary truth is the subject matter of mathematics. It is not the reward we get for doing mathematics". This is a good exploration of fallibility, the relationship of physics to mathematics and how science is, in a sense, logically prior to mathematics (and logic for that matter!)...all because proof is a physical process.

The nature of proof and mathematics as a creative enterprise. Not all that is true can be proved as such, the high hopes of David Hilbert for placing the entirety of mathematics on a "firm foundation", the mathematical world-shattering results of Kurt Gödel which frustrated that project, a history of proof and finally Roger Penrose and whether human brains are computers in the Turing sense. And some very long remarks by me, especially in the introduction. Become a subscriber at https://patreon.com/tokcast?utm_medium=unknown&utm_source=join_link&utm_campaign=creatorshare_creator&utm_content=copyLink

Drawing on Chapter 15 "The Evolution of Culture" from "The Beginning of Infinity" by David Deutsch and then applying it to some special cases.

Come and chat to me about this or anything else at https://www.getairchat.com/brett

Timestamps:

00:00 Speech, Trade and Democracy

02:39 Is Democracy under attack?

07:05 Free Speech as Error Identification

09:14 Limits on Free Speech?

13:02 Case Study 1: North Korea

14:18 Case Study 2: Afghanistan and Iraq

17:30 Case Study 3: South Korea

19:43 Case Study 4: China

24:43 The Evolution of Culture by David Deutsch 1

29:43 Protecting liberty in Western Nations

30:30 Bringing Liberty to nations without it.

32:25 Case Study 5: Japan

35:01 Immigration: Why worry?

35:58 The Evolution of Culture by David Deutsch 2

39:01 Preserve the means of error correction at all costs

Support me at www.bretthall.org

00:00 Introduction

08:03 Interview Begins

09:42 How Chiara found herself at the foundations of physics

15:30 How Chiara found Everett

19:13 No Special Physics is required for Observers

21:02 What is a counterfactual? How is it linked to a constructor?

29:05 What is (classical) information? How is it different to quantum information?

32:30 Quantum Information is more constrained. This makes it more powerful.

34:08 Is the universe made of information?

38:04 The Simulation Hypothesis

40:33 The second law of thermodynamics

53:16 The AI Apocalypse?

58:02 How do we help a human become passionate about knowledge?

59:39 The Fine Tuning Problem

01:07:48 The Constructor Theoretic Notion of Knowledge

01:10:52 Constructor Theoretic Knowledge as a window on the origins of life.

01:12:16 The links between physics, epistemology and biology

01:14:15 Experimentally testing the quantum nature of gravity

01:26:05 Where to find out more

Support me by following the links at www.bretthall.org