Episodes

  • 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

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  • 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

  • The certainty of mathematics and its place in the supposed hierarchy of subjects (assumed to be above science which is itself above philosophy in turn). Some more remarks on Bayesianism and somehow ghosts and alien life.

  • Everything and more one might ever want to know about the topic...that other epistemology people often talk about. The central project is to distinguish between 4 "species" of what is often called "Bayesianism"

    1. Bayes' Theorem.

    2. Bayesian Statistics.

    3. Bayesian Reasoning

    4. Bayesian Epistemology.

    Actual timestampes and chapters are:

    00:00 - Introduction to this podcast

    02:55 Epistemology

    11:30 Substrate Independence

    12:30 Inexplicit Knowledge/Knowledge without a knower

    21:30 Explanatory Universality and Supernaturalism

    24:30 When we lack good explanations

    29:00 Rational Decision Theory

    33:39: Bayes’ Theorem

    41:40 Bayesian Statistics

    1:07:50 Bayesian Reasoning

    1:16:00 Bayesian “Epistemology”

    1:20:13: Quick Recap

    1:20:49 A question from Stephen Mix

    1:21:50 “Confidence” in epistemology

    1:26:13 Measurement and Uncertainty

    1:31:50 Confidence and experimental replication

    Join the conversation https://getairchat.com/s/p3ql7kNB

  • This episode is an introduction to the chapter. Although there are some readings, they are limited and I provide context by diving deep into David's more recent work on all this. Specifically we go through the connection of Chapter 10 here (published in 1997) and Chapter 5 "The Reality of Abstractions" from "The Beginning of Infinity" (published in 2011) and then also in light of David's recent speech given at his Dirac Medal award ceremony (published in 2017) - here is the timestamped link to that https://www.youtube.com/live/J7HeDX_7... and the text of that speech is online here: https://www.daviddeutsch.org.uk/wp-co... None of that is essential reading (or listening) for this episode - but it can help. As always - buy "The Fabric of Reality" and read along as I never read the entire chapter - just excerpts!

  • Commentary (and Explainer) This podcast is largely an op-ed about the "feminisation" of Western militaries and the effect of so-called "diversity, equity and inclusion" ideologies on modern defence forces. I look at what the purpose of a military is and the tension between its aims and the ways some arms of some defence forces are "marketing" themselves to their own people. Of chief concern to some has been the way the US army has chosen to attempt to recruit people into its ranks. Timestamps/Chapters and references below.

    00:00 Introduction secs: concerns of late about military decline/changes in standards

    00:25 Concerns about politicising the military

    1:23 - Should physical standards be lowered to accommodate “diversity” in the military?

    2:18 The Military as a deterrent (as nuclear weapons are a special case of) First Pass

    3:08: The “Mutually Assured Destruction” trope is a lie

    5:01 - Chinese/Russian tech (military & other) is a stolen, poor imitation of Western innovation

    6:20 - A comparison of military forces in terms of numbers (expenditure, land/air/manpower, materiel, capabilities)

    10:30 The difference in Military Cultures (Jocko Willink on decentralised command).

    12:14 - Gandalf’s cameo

    12:18 - raw soldier numbers vs army cultures and capabilities

    12:31 Case Study: North Korea “the world’s 4th largest army”.

    13:54 - Case Study: The Russia Ukraine war

    14:24 Case Study: The First Gulf War - The Tank Battle

    16:18 Case study: the 6 day Israeli war

    17:46 The Military as a deterrent (Second Pass)

    19:08 Gratuitous Holiday Snap

    19:56 The Mother Military Thesis

    21:56 North Korea/Communism and Cancel Culture

    22:51 Contemporary Western Nations and Cancel Culture

    23:27 Woke Culture and Toxic Masculinity

    26:23 Is there sexism in custody proceedings?

    27:54 - Toxic “Father” Masculinity vs A Feminist “Mother” Military

    28:39 The US Army recruitment advertisement controversy 30:53 Alan Watts on “Prickles and Goo” 31:21 Masculine and Feminine traits: some comparisons

    33:50 James Damore and “the Google Memo” - commentary

    34:19 The function and public face of the military 35:46 Pathological Goo: Jordan Peterson and The Devouring Mother

    37:14 Early Signs of military culture rot?

    39:04 Exclusive Clubs, Bouncers and Gay Culture

    39:57 The Military as a Deterrent (Third Pass)

    40:34 - Comparison of Recruitment Tactics - US Army vs US Marines or US Army vs Russian/Chinese Army.

    41:24 Conclusions

    42:11 Credits, How to support the channel, podcast and me

    References: 1. https://youtu.be/MIYGFSONKbk?si=C8mFqnObEburxXqz

    2. A recent article from Australian media about coercion of "LGBTQIA+" ideologies on cadets: https://www.abc.net.au/news/2023-08-27/adf-academy-cadets-claim-they-were-pressured-to-remove-uniforms/102780562

    3. US Marine corps recruitment ad for comparison: https://www.youtube.com/watch?v=O9gTAjbiQEM

    4. Humorous Aussie analysis of US vs Russian & Chinese army recruitment commercials: https://www.youtube.com/watch?v=FXmyWdZfdgk

    5. Ex-Marine comments on US Military Matters (Jameson's Travels) - https://www.youtube.com/@UC-N44TadAniwC7v8Zj858nQ #woke #feminism #military #transition #army #philosophy "Like" my video and "subscribe" to my channel :)

  • Very brief readings from and lengthy reflections upon David Deutsch's paper "The Philosophy of Constructor Theory" published here https://link.springer.com/article/10.... and available in full here: https://www.constructortheory.org/por... #physics #knowledge #philosophy #epistemology #daviddeutsch #science

    Also available on Youtube at https://www.youtube.com/watch?v=hMCx2Com7LU

    Discuss this or any episode of ToKCast on ToKChat: a channel on "Airchat" available here for download for iPhone and Android: https://www.getairchat.com/

    ToKChat is here: https://www.getairchat.com/bretthall/tokchat

    Timestamps/chapters:

    00:00 Introduction

    00:45 Predictions are not always possible

    01:27 The Unpredictable

    02:33 The Content of Future Theories

    03:36 Better Theories Better Explain What Exists

    04:31 The Principle of Testability

    04:58 The Negation of an Explanation is Not an Explanation

    06:04 Knowledge is the most significant entity in the universe

    06:33 The Most Important Kind of Abstract Constructor Is Knowledge (Part 1)

    07:22 The Most Important Kind of Abstract Constructor Is Knowledge (Part 2)

    07:44 Physics is almost entirely the study of the effects of knowledge

    08:40 Knowledge is not primarily about the content of minds

    09:20 People are more significant than any religion realises

    10:15 Wealth = Knowledge + Resources

    11:15 Ultimately, Knowledge is the Only Scarce Resource

    12:05 Knowledge determines which physical transformations happen

    13:17 Knowledge is Information with Causal Power

    14:13 Knowledge is Substrate Independent (Part 1)

    15:11 Knowledge is Substrate Independent (Part 2)

    16:01 Knowledge is Substrate Independent (Part 3)

    16:12 Knowledge is Substrate Independent (Part 4)

    17:01 Knowledge is Substrate Independent (Part 5)

    17:44 Knowledge is Substrate Independent (Part 6)

    18:34 Knowledge is Substrate Independent (Part 7)

    19:35 The Role of Emotion in Objective Knowledge Creation

    20:31 On Why People are Unique

    21:16 Humans Routinely Defy Their Instincts

    22:13 People are Universal Explainers

    23:16 Human Brains obey the Laws of Physics

    23:57 Many “Rationalists” Endorse the Supernatural

    24:32 Good Explanations and Decision Making

    25:33 Inexplicit Knowledge and Misconceptions

    26:38 Quaila: We have them. We cannot describe them

    27:42 Intuitions are conjectures

    28:51 Either you have a Good Explanation or you don’t

    29:45 Vibes can be an indication to investigate further

    30:43 Knowledge is not just a “decision engine”

    31:31 Obsession with guessing the future is irrational

    32:15 A “simulation” of a mind is a mind.

    33:08 We cannot predict the output of a creative entity

    34:04 Knowledge Rekindles Light When Other Lights Go Out.

  • This is a "return to regular format" episode in one respect - readings from and reflections upon "The Fabric of Reality" but also a departure from regular formatting in another respect: I teach a bunch of simple mathematics. This is for those who might think "quantum computation" and "quantum algorithms" will be forever beyond me. They are not! I begin with (quite literally) primary school mathematics level stuff (what's a prime number, what is the "fundamental theorem of arithmetic") and very gradually move up into algebra and some modular arithmetic and present examples using real numbers of what the problem is and then lead us to a place where we can glimpse the solution (which is Shor's Algorithm). I do not promise to bring the listener to a graduate quantum physics-degree-level of proficiency in quantum information theory and cryptography - but you will gain quite some insight. I refer to the following more in-depth expositions of all this and hopefully bridge the gap I think is there between "I know a little bit of maths and physics" and the kind of thing the following more "high level" videos offer (which I present in order of increasing technical difficulty) 1. The PBS Infinite Series on all this stuff is brilliant. In particular this introduction: • How to Break Cryp... and this video focussed more narrowly on Shor's algorithm: • Hacking at Quantu... 2. Here is Peter Shor himself explaining the history of his work: • The Story of Shor... 3. Artur Ekert's graduate level free online course on Quantum Information Theory: https://www.youtube.com/@ArturEkert/v... in particular his lecture focussed on Shor's Algorithm: • IQIS Lecture 6.9 ... (which, aside from "The Fabric of Reality" itself, served as the basis for this episode).

  • I recommend the version found here that contains visuals and music: https://www.youtube.com/watch?v=mlvgxEBekP4

    However the same message will come through on this audio only podcast.

    Full Credit for all ideas to:

    James (Jim) Pierce

    Naval and Nivi

    and

    David Deutsch

    With mistakes all my own

    See also James' website (and relevant article) here: https://www.james-pierce.com/writings/effortless-stoicism

    His instagram account including the original "Effortless Stoicism" video here: https://www.instagram.com/p/CuuDzL9sKOG/

    His Twitter and relevant thread here: https://twitter.com/jimmpierce/status/1190810962493788160?s=20

    Naval and Nivi's work on "How to get rich" where you can download their podcast from Naval's website here: https://nav.al/rich

    Or the Youtube version: https://www.youtube.com/watch?v=1-TZqOsVCNM

    See also Akira The Don's outstanding magical version along with other original music featuring Naval here: https://www.youtube.com/playlist?list=OLAK5uy_nX7x9AzwUTaGMFNVAxrLNXUJrKFotQ84Y

    And my new favorite Naval/Nivi/Akira song here: https://www.meaningwave.com/blogs/meaningwave/akira-the-don-naval-ravikant-ft-nivi-you-will-need-to-rent-your-time-to-get-started-single

  • This is a cross-post from my Substack podcast "The 3Rs: Reality, Reason, Rationality" the text of which can be found here: https://bretthall.substack.com/p/where-do-ideas-come-from?sd=pf#details

    This diagram is also relevant:

  • Science news from a "critical rational" perspective. No "believing" in explanations here, no time for instrumentalism and a focus on good explanations of the evidence.

    Introduction (epistemology in science): 00:00

    Dark Matter: 04:32

    Modified Newtonian Dynamics (MOND): 08:12

    Statistical confidence in physics: 15:23

    Instrumentalism in modern physics: 19:00

    Fusion Power 'News': 22:09

    "Spinoffs" from fusion research: 24:56

    Advice for investors in pure science: 28:26

    James Webb Space Telescope latest: 31:59

    Concluding Remarks: 37:42

  • Here in this second-to-last episode on the discussion of Chapter 9 from the Fabric of Reality we discuss some of the key distinctions between the classical and quantum - the philosophical and scientific implications and then some of the current experimental approaches to (and reporting on) the actual engineering of these devices.

  • This serves as "part 2" of my "Are Consciousness and Creativity the same thing?" podcast, the Youtube version of which can be found here: https://www.youtube.com/watch?v=lrjY4fR-qMU

  • This podcast was originally produced on Airchat: https://www.getairchat.com/bretthall/bretthall It is all about an interview that can be found here: https://www.youtube.com/watch?v=4fv4Uz_i1iQ

  • This podcast episode is based around two sets of chits (two "chats") found on airchat at https://www.getairchat.com/bretthall/bretthall?t=440630 The articles associated with these chits and in the latter case many links are here:

    https://www.bretthall.org/blog/the-white-swan-and-red-pen and here:

    https://www.bretthall.org/blog/the-problem-with-fallibilism