Tim Maudlin | Bell’s Theorem and Beyond: Nobody Understands Quantum Mechanics

The Cartesian Cafe

Tim Maudlin is a philosopher of science specializing in the foundations of physics, metaphysics, and logic. He is a professor at New York University, a member of the Foundational Questions Institute, and the founder and director of the John Bell Institute for the Foundations of Physics.

Patreon (bonus materials + video chat):
https://www.patreon.com/timothynguyen

In this very in-depth discussion, Tim and I probe the foundations of science through the avenues of locality and determinism as arising from the Einstein-Poldosky-Rosen (EPR) paradox and Bell's Theorem. These issues are so intricate that even the Nobel Prize committee incorrectly described the significance of Bell's work in their press release for the 2022 prize in physics. Viewers motivated enough to think deeply about these ideas will be rewarded with a conceptually proper understanding of the nonlocal nature of physics and its manifestation in quantum theory.

I. Introduction 00:00 :

• 00:25: Biography
• 05:26: Interdisciplinary work
• 11:54 : Physicists working on the wrong things
• 16:47 : Bell's Theorem soft overview
• 24:14: Common misunderstanding of "God does not play dice."
• 25:59: Technical outline

II. EPR Paradox / Argument

• 29:14 : EPR is not a paradox
• 34:57 : Criterion of reality
• 43:57 : Mathematical formulation
• 46:32 : Locality: No spooky action at a distance
• 49:54 : Bertlmann's socks
• 53:17 : EPR syllogism summarized
• 54:52 : Determinism is inferred not assumed
• 1:02:18 : Clarifying analogy: Coin flips
• 1:06:39 : Einstein's objection to determinism revisited

III. Bohm Segue

• 1:11:05 : Introduction
• 1:13:38: Bell and von Neumann's error
• 1:20:14: Bell's motivation: Can I remove Bohm's nonlocality?

IV. Bell's Theorem and Related Examples

• 1:25:13 : Setup
• 1:27:59 : Decoding Bell's words: Locality is the key!
• 1:34:16 : Bell's inequality (overview)
• 1:36:46 : Bell's inequality (math)
• 1:39:15 : Concrete example of violation of Bell's inequality
• 1:49:42: GHZ Example

V. Miscellany

• 2:06:23 : Statistical independence assumption
• 2:13:18: The 2022 Nobel Prize
• 2:17:43: Misconceptions and hidden variables
• 2:22:28: The assumption of local realism? Repeat: Determinism is a conclusion not an assumption.

VI. Interpretations of Quantum Mechanics

• 2:28:44: Interpretation is a misnomer
• 2:29:48: Three requirements. You can only pick two.
• 2:34:52: Copenhagen interpretation?

Further Reading:

J. Bell. Speakable and Unspeakable in Quantum Mechanics

T. Maudlin. Quantum Non-Locality and Relativity

Wikipedia: Mermin's device, GHZ experiment

Twitter: @iamtimnguyen

Webpage: http://www.timothynguyen.org