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We are an international weekly online seminar for students and experts in the philosophy and history of physics. We meet each Monday from 13:00-14:30 (UK time) when there is not a Sigma Club meeting. The format is discussion-based: bring your questions and comments on the reading, or just listen on the discussion! Please contact the organisers if you would like to attend: Jeremy Butterfield (jb56@cam.ac.uk), Bryan W. Roberts (b.w.roberts@lse.ac.uk), and Dominic Ryder (d.ryder@lse.ac.uk).

Upcoming

This term we continue our discussion of black hole thermodynamics.

Wk Date Topic Reading
1 22 Jan 2024, 13:00-14:30 GMT What is black hole thermodynamics? Wallace (2019) The case for black hole thermodynamics part II: Statistical mechanics
2 29 Jan 2024, 13:00-14:30 GMT What is black hole thermodynamics? Wüthrich (2018) Are black holes about information? Optional further reading: Bekenstein (1973) Black holes and entropy
3 05 Feb 2024, 13:00-14:30 GMT What is black hole thermodynamics? Prunkl and Timpson (2019) Black Hole Entropy is Thermodynamic Entropy. Optional: Curiel (2023 manuscript) Are classical black holes hot?
4 12 Feb 2024, 13:00-14:30 GMT Information Loss Maudlin (2018) (Information) Paradox Lost, and Weatherall and Manchak (2018) (Information) Paradox Regained? A Brief Comment on Maudlin on Black Hole Information Loss
5 19 Feb 2024, 13:00-14:30 GMT No Bootcamp: Sigma Club LSE Sigma Club Seminar (Hybrid), 15:00-16:30 GMT: Bryan W Roberts, 'Is there a problem of thermodynamic irreversibility? (Optional: to prepare for the coming weeks on black hole information loss, check out Belot, Earman and Ruetsche (1999) and Rovelli and Vidotto (2014) Planck Stars)
6 26 Feb 2024, 13:00-14:30 GMT Information Loss Wallace (2020) Why Black Hole Information Loss is Paradoxical. Optional further reading: Page (1993) Information in black hole radiation
7 04 Mar 2024, 13:00-14:30 GMT Information Loss Saakshi Dulani, "The Phantom of the Space Opera: Why Black Hole Information Loss is Really Paradoxical", manuscript to be circulated
8 11 Mar 2024, 13:00-14:30 GMT No Bootcamp - Sigma Club LSE Sigma Club Seminar (Hybrid): Alex Franklin, 'Weather Probabilities are Ontic and Objective'
9 18 Mar 2024, 13:00-14:30 GMT TBD TBD
10 25 Mar 2024, 13:00-14:30 GMT No Bootcamp - Sigma Club LSE Sigma Club Seminar (Hybrid): Gábor Hofer-Szabó, 'Operational equivalence and causal structure'

Past Seminars

This term we discussed thermodynamics, black holes, and black hole thermodynamics. After getting off the ground with an article on thermodynamics, we spent some weeks thinking about the justification for treating black holes as thermodynamic objects. We then moved on to some papers covering issues in quantum field theory on curved spacetimes including the breakdown of predictability due to black hole evaporation, the trans-Planckian problem, and the Unruh effect.

Wk Date Topic Reading
1 23 Oct 2023, 13:00-14:30 BST Uffink on the 2nd Law of Thermodyanmics Jos Uffink (2001, sections 1-6) Bluff Your Way in the Second Law of Thermodynamics. Optional Reading: The rest of Uffink (2001)!
2 30 Oct 2023, 13:00-14:30 GMT Analogy between Black Hole Mechanics and Thermodyanmics Dougherty and Callender (2016) Black hole thermodynamics: More than an analogy? Optional Reading: Hawking (1974) Black Hole Explosions?
3 06 Nov 2023, 13:00-14:30 GMT Wallace on Black Hole Thermodynamics Wallace (2018) The case for black hole thermodyanmics, Part I: phenomenological thermodynamics. Optional Reading: Hawking (1975) Particle creation by black holes
4 13 Nov 2023, 13:00-14:30 GMT Breakdown of Predictability due to Evaporation Hawking (1976) Breakdown of predictability in gravitational collapse. Optional Reading: Wald (1975) On particle creation by black holes; Landsman (2021, section 10.12) Foundations of General Relativity (Radboud University Press)
5 20 Nov 2023, 13:00-14:30 GMT The Trans-Planckian Problem Gryb, Palacios and Thebault (2021) On the universality of Hawking radiation. Optional Reading: Fredenhagen and Haag (1990) On the derivation of Hawking radiation associated with the formation of a black hole.
6 27 Nov 2023, 13:00-14:30 GMT Earman on the Unruh Effect Earman (2011) The Unruh Effect for Philosophers
7 04 Dec 2023, 13:00-14:30 GMT A new idealisation paradox for black holes? Dominic Ryder, "The idealisation paradox in Hawking radiation", circulated by email
8 11 Dec 2023, 13:00-14:30 GMT TBD TBD

We will again begin this term with the delight of a book chapter manuscript by Erik Curiel on black hole thermodynamics, and then continue into the foundations of thermal and statistical physics.

Wk Date Topic Reading
1 13 Feb 2023, 15:00-16:30 GMT Curiel on Hawking Erik Curiel, "A Primer on the Hawking Effect", Harvard Black Hole Initiative, Special Zoom Link Here. Ordinary bootcamp will not take place this week so that we can attend Erik's lecture, as a primer also for reading his book manuscript.
2 27 Mar 2023, 15:00-16:30 GMT Curiel on Entropy Erik Curiel, "Energy, Entropy and the Intimate Relations between the Two in Semi-Classical Gravity", Harvard Black Hole Initiative, Special Zoom Link Here. Ordinary bootcamp will not take place this week so that we can attend Erik's lecture, as a primer also for reading his book manuscript, next week!
3 06 Mar 2023, 14:00-15:30 Sigma Club Tushar Menon Sigma Club lecture, More Information and Zoom Link: "Inferential Scientific Realism". Abstract: In this talk, following the Sellars-Brandom tradition, I argue that the semantic order of explanation should be reversed: a scientific expression gets its meaning via the inferences in which it is caught up....
4 27 Mar 2023, 15:00-16:30 Black hole thermodynamics Curiel chapter, "The Hawking Effect", from his book manuscript

This term we will begin a book manuscript by Erik Curiel on black hole thermodynamics, and read Sam Fletcher's new manuscript on the philosophy of general relativity for the Cambridge Elements series, as well as a final installment of Jeremy's book on the Multiverse.

Wk Date Topic Reading
1 03 Oct 2022, 13:30-15:00 Representation in General Relativity Fletcher Foundations of General Relativity Manuscript, Chapters 1-2 ONLY
2 10 Oct 2022, 13:30-15:00 Ontology in General Relativity Fletcher Foundations of General Relativity Manuscript, Chapters 3 and 5
3 14 Nov 2022, 13:30-15:00 Semiclassical gravity and black hole thermodynamics Erik Curiel's SEP article, Singularities and Black Holes, Sections 3, 5 and 6 only. Optional related Curiel video lectures, "A Primer on Black Hole Thermodynamics and the Hawking Effect", Part I and Part II (with slides here).
4 21 Nov 2022, 13:30-15:00 Semiclassical gravity and black hole thermodynamics Curiel, "Black Holes as Thermodynamical Systems: The Central Problem", Chapter VI of his forthcoming book, Simulacra, Saturnalia, and Wild Extrapolation: Black Hole Thermodynamics and Semi-Classical Gravity As a Way of Life.
5 05 Dec 2022, 13:30-15:00 Foundations of GR Foundations of General Relativity Manuscript, Chapter 6
6 12 Dec 2022, 13:30-15:00 Foundations of GR Curiel Chapter, "Chapter 12, 'The cogency of semi-classical gravity'. Optional related video lecture, "On the Cogency of Quantum Field Theory on Curved Spacetime and Semi-Classical Gravity".

This term we read Jeremy Butterfield's book manuscript on the multiverse, and also embarked on some further remarkable adventures in the quantum measurement problem..

Wk Date Topic Reading
1 05 Apr 2022 Introduction to the multiverse Butterfield Chapter 1 "Introduction" and Chapter 2 "Physics and Philosophy from 1600 to 1900"
2 19 Apr 2022 Logically possible worlds Butterfield Chapter 3 "All the logically possible worlds"
3 03 May 2022 The Everettian multiverse Butterfield Chapter 4, "All the worlds encoded in the quantum state of the cosmos"
4 10 May 2022 The Deutsch-Wallace Approach Dawid and Thébault (2015), 'Many worlds: decoherent or incoherent?' Optional ancillary reading: Dawid and Thébault (2014), 'Against the empirical viability of the Deutsch–Wallace–Everett approach to quantum mechanics'. The approach that these papers critique is presented in detail by Wallace (2012), especially Sections 4.8-4.12 (with proofs of the decision-theoretic results appearing in Appendix C).
5 17 May 2022 The Cosmological Multiverse Butterfield Chapter 5
6 24 May 2022 Bohemian Mechanics and Determinism Landsman (manuscript) Bohmian mechanics is not deterministic. Optional ancillary reading: Valentini (2020) Foundations of statistical mechanics and the status of the Born rule in de Broglie-Bohm pilot-wave theory
7 31 May 2022 Everett and Branch Counting Saunders (2021) Branch counting in the Everett Interpretation of Quantum Mechanics
8 07 June 2022 Probabilities in Quantum Mechanics Myrvold (2021) Beyond Chance and Credence: A Theory of Hybrid Probabilities, Chapter 9: Probabilities in Quantum Mechanics
9 14 June 2022 Psi-Ontic and Psi-Epistemic Models Luc (manuscript) States vs. changes of states: A reformulation of the ontic vs. epistemic distinction in quantum mechanics (9 April draft)
comic panel displaying a scene in which a person is baking cookies in the kitchen becomes progressively stranger as one moves into ever more distant parallel universes

This term continued our discussion of the hole argument.

Wk Date Topic Reading
1 25 Jan 2022 On the mathematics and metaphysics of the hole Pooley and Read (2021), "On the mathematics and metaphysics of the hole argument"
2 1 Feb 2022 General remarks and morals on symmetries Gomes (2022), Chapter 1 ONLY of Why gauge? Conceptual Aspects of Gauge theories (Cambridge PhD Thesis, 21 Dec 2021 version)
3 8 Feb 2022 The hole argument: Same diff? Gomes (2022), Chapter 2 ONLY (skipping 2.3) of Why gauge? Conceptual Aspects of Gauge theories (Cambridge PhD Thesis, 21 Dec 2021 version)
4 15 Feb 2022 Some philosophical implications of the hole Stachel (2014), "The Hole Argument and Some Physical and Philosophical Implications" (Springer Open Access)
5 22 Feb 2022 What hole? Halvorson and Manchak (forthcoming), What hole argument?
6 01 Mar 2022 Again: what hole? Halvorson and Manchak (forthcoming) What hole argument? - Further discussion.
7 08 Mar 2022 On the well-posedness of the substantivalist question Erik Curiel, On the existence of spacetime structure
8 15 Mar 2022 Jacobs and Cudek - Two new arguments on the hole Circulated via email - Ask Jeremy or Bryan if you don't receive it!
9 22 Mar 2022 Reopening the hole argument Landsman, Reopening the Hole Argument manuscript, regarding David Hilbert's formulation of the hole argument.
Break: We will not meet on 29 Mar 2022, so you can collapse after the Cambridge term. But we meet again on 5 Apr 2022 with our own Jeremy Butterfield: on the Multiverse!

This term in philosophy of physics bootcamp, we faced the storied hole argument.

Wk Date Topic Reading
1 12 Oct 2021 The Hole Story Norton and Earman (1987) "What price spacetime substantivalism? The hole story", together with Norton (2019) "The hole argument", Stanford Encyclopedia of Philosophy.
2 19 Oct 2021 Substantivalism and Relationism Pooley (2012) "Substantivalist and relationist approaches to spacetime"
3 26 Oct 2021 The Hole Truth Butterfield (1989) "The hole truth". Optional further reading: Butterfield (1987) "Substantivalism and determinism", and Brighouse (1994) "Spacetime and holes"
4 02 Nov 2021 Regarding the hole argument Weatherall (2017) "Regarding 'the hole argument" and Roberts Regarding 'Leibniz equivalence'
5 09 Nov 2021 Prehistory of the hole argument Weatherall (2020) "Some philosophical prehistory of the hole argument". Optional further reading: Stein (1975) "Some philosophical prehistory of general relativity"
6 16 Nov 2021 New work for counterpart theorists Belot (1995) "New Work for Counterpart theorists: Determinism" and Melia (1999) "Holes, haecceitism and two conceptions of determinism". Optional further reading: Belot (1995) "Determinism and ontology"
7 23 Nov 2021 When and where things happen Belot (2018) "50 million Elvis fans can't be wrong" Optional ancillary reading: Fletcher (2021) "On representational capacities, with an application to general relativity"
8 30 Nov 2021 Physical equivalence and symmetry-related models Joanna Luc (Forthcoming, Synthese), "Arguments from scientific practice in the debate about the physical equivalence of symmetry-related models" Come back next term: we plan to do a few more meetings on the hole argument, before turning to our next topic!

This seminar dealt with geometric techniques and with symmetry in the philosophy of physics, in both Hamiltonian (symplectic) mechanics and in its (2n+1f)-dimensional cousin contact geometry.

Wk Date Topic Reading
1 13 Apr 2021 Units and physical dimension Carlos Zapata Carratala, "Dimensioned algebra" (esp. Section 2). This work asks: "How do we rigorously implement physical dimension into current mathematical theories of physics?" Optional further background reading: Jacobi Geometry and Hamiltonian Mechanics: the Unit-Free Approach (especially Sections 1, 4 and 5), and also: Dimensioned Algebra and Geometry.
2 20 Apr 2021 Spacetime State Realism Swanson (2020) How to be a relativistic spacetime state realist" (Optional related readings: Wallace and Timpson (2010) and Wallace (2006) "In Defence of Naiveté" and Wallace and Timpson (2010) Quantum Mechanics on Spacetime, I: Spacetime State Realism")
3 27 Apr 2021 BREAK We'll be back next week for more philosophy of physics! In the meantime, try this reminder of our place in the universe: Zoom Out
4 04 May 2021 Direct Empirical Significance of symmetries NEW TIME: 4:45pm BST Gomes (manuscript) Holism as the empirical significance of symmetries
5 11 May 2021 Black Holes Landsman, Chapter 10, "Black Holes", from book manuscript (Optional further materials: Chapter 9, "Black Holes I: Exact Solutions" and Updated Bibliography)
6 18 May 2021 Thermodynamic Mixing James Wills, "Homogeneity and ientity in thermodynamics" (manuscript)
7 25 May 2021 Analogue Black Holes Grace Field, "The latest frontier in analogue gravity: new roles for analogue experiments" (manuscript)
8 01 Jun 2021 DISanalogies between black holes and acoustics Curiel, "Dumb Hole Disanalogies" (2-page manuscript)
9 08 Jun 2021 The Aharanov-Bohm Effect Ruward Mulder, "Gauge‐Underdetermination and Shades of Locality in the Aharonov–Bohm Effect"
10 15 Jun 2021 Gauge Caspar Jacobs, "Case Study on Gauge Quantities"

In the first five weeks of this seminar we finished the book manuscript of Bryan Roberts, Reversing the Arrow of Time, following our reading of the first three chapters in Michaelmas Term, mixed in with some influential recent articles on symmetry and on the nature of the CPT transformation.

Wk Date Topic Reading
1 19 Jan 2021 Philosophy of time symmetry Roberts, Chapter 4
2 26 Jan 2021 Symmetries and reference Dewar (2019) 'The role of symmetry in the interpretation of physical theories'
3 02 Feb 2021 Symmetry, duality and gauge Martens and Read (2020) "Sophistry about symmetries?". Option further reading: Witten (2017) "Symmetry and emergence"
4 09 Feb 2021 QFT and CPT Swanson (2017) A philosopher's guide to the foundations of quantum field theory and the (short) review, Swanson (2018) Review of Jonathan Bain's CPT Invariance and the Spin-Statistics Connection
5 16 Feb 2021 Caulton on Symmetry and Gauge Caulton (2015) On the role of symmetry in the interpretation of physical theories
6 23 Feb 2021 Misfiring arrows of time Roberts, Chapter 5
7 02 Mar 2021 Are Rindler quanta real? Clifton and Halvorson (2001) Are Rindler quanta real? Inequivalent particle concepts in quantum field theory, and/or Buchholz and Verch, Unruh versus Tolman: on the heat of acceleration. Supporting handout: Bryan and Jeremy handout on the Unruh effect.
8 09 Mar 2021 CPT reversal: The weak and strong arrows Roberts Chapter 6
9 09 Mar 2021 More on CPT + Unruh Redux Roberts Chapter 6 (updated with some minor edits) plus any final discussion on the Unruh effect.

In this seminar we read the manuscript of Neil Dewar's book, Structure and Equivalence, which has since been published in Cambridge University Press's Elements: See here for access options. We will then began the manuscript by Bryan Roberts on Reversing Time's Arrow, which is now published Open Access through Cambridge University Press.

Wk Date Topic Reading
1 13 Oct 2020 Introduction and Overview No Reading!
2 20 Oct 2020 Logic: Models, theories, and Ramsey sentences Dewar Part 1
3 27 Oct 2020 Newtonian Mechanics Dewar Part 2
4 03 Nov 2020 Electromagnetism Dewar Part 3
5 10 Nov 2020 Categories and Theories Dewar Part 4 and Appendices/Bibliography
6 17 Nov 2020 A brief history of time reversal Roberts Chapter 1, Time reversal and time's arrow
7 24 Nov 2020 What time reversal means Roberts Chapter 2, What time reversal means
8 01 Dec 2020 Time reversal in physical theory Roberts Chapter 3, Time reversal in physical theory

This seminar, like fine wine with fine dining, paired a classic paper 🍷 in philosophy of spacetime with a chapter 🍔 from Klaas Landsman's book on the foundations of general relativity, when it was still in draft form. Participants were welcomed to read just one or the other, depending on their interests, or both! Following this seminar, the manuscript was published Open Access by Radboud University Press as: Foundations of General Relativity: From Einstein to Black Holes.

Wk Date Topic Reading
1 11 Aug, 16:30 BST Einstein's philosophy of space, time and geometry 🍔 Landsman Chapter 1 paired with 🍷 Einstein (1921), "Geometry and Experience" Notable further reading: Norton (1993), "General covariance and the foundations of general relativity: eight decades of dispute"; Lehmkuhl (2014), "Why Einstein did not believe that general relativity geometrizes gravity"; and Janssen and Renn (2015), "Arch and scaffold: How Einstein found his field equations".
2 18 Aug, 16:30 BST The spacetime manifold 🍕 Landsman Chapter 2 paired with 🍷 Riemann (1854) "On the Hypotheses, Which Lie at the Basis of Geometry" Notable recent work: Manchak (2016), "Epistemic 'holes' in space-time" and Doboszewski (2019), "Epistemic Holes and Determinism in Classical General Relativity". See also Roberts (unpublished) "Notes on holes"
3 25 Aug, 16:30 BST Physical geometry 🍖 Landsman Chapter 3 paired with 🍷 Reichenbach (1958) "The problem of physical geometry", Chapter 1.3 of The Philosophy of Space and Time. Notable recent work: Weatherall and Manchak (2013), "The geometry of conventionality" and Pitts (2016) "Space–time philosophy reconstructed via massive Nordström scalar gravities? Laws vs. geometry, conventionality, and underdetermination".
4 01 Sep, 16:30 BST Curvature and underdetermination 🍗 Landsman Chapter 4 paired with 🍷 Earman (1989) "Chapter 2: Classical space-times", in World enough and spacetime. Notable recent work: Knox (2011) "Newton–Cartan theory and teleparallel gravity: The force of a formulation" and Weatherall (2016) "Are Newtonian Gravitation and Geometrized Newtonian Gravitation Theoretically Equivalent?"
5 08 Sep, 16:30 BST Causal structure 🥘 Landsman Chapter 5 paired with 🍷 Geroch (1977) Prediction in General Relativity. Notable extra reading: Manchak (2008) "Is prediction possible in general relativity" and reply, McCoy (2017) "Prediction in general relativity"
6 15 Sep, 16:30 BST Spacetime singularities 🌮 Landsman Chapter 6 paired with 🍷 Earman (1995) Chapters 2. Notable extra reading: Geroch (1968) "What is a singularity in general relativity", Earman (1996) "Tolerance for spacetime singularities", Earman (1998) "The Penrose-Hawking Singularity Theorems: History and Implications and Curiel (1999) "The analysis of singular spacetimes" (see also Curiel's SEP article on singularities)
7 22 Sep, 16:30 BST Einstein's Equations and Cosmic Censorship 🌭 Landsman Chapter 7 paired with 🍷 Earman (1995) Chapter 3 and Penrose (1979) "Singularities and time asymmetry". Further reading: Doboszewski (2017) "Hyperbolic spacetimes in classical general relativity: A philosophical survey"
8 29 Sep, 16:30 BST The problem of time 🍝 Landsman Chapter 8 paired with 🍷 Butterfield and Gomes (manuscript), "Geometrodynamics as Functionalism about Time"
9 06 Oct, 16:30 BST Black Holes 🥪 Landsman Chapter 9 paired with 🍷 Curiel (2019) "The many definitions of a black hole"
Wk Date Topic Reading
2 04 Aug, 16:30 BST Healey on Gauge, Part 2 Sections 4.4 + 4.5 of Healey's (2007) book. Optional: Read the whole chapter!
1 28 Jul, 16:30 BST Healey on Gauge, Part 1 Sections 4.1 + 4.2.1 of Healey's (2007) book
Wk Date Topic Reading
8 20 Jul, 16:30 BST Final Redux Reviews of Halvorson (2019), whichever you would like to read: Andreas, Davey, Dewar, van Fraassen, Weatherall.
7 13 Jul, 16:30 BST Reviews of Logic in Philosophy of Science Reviews of Halvorson (2019), whichever you would like to read: Andreas, Davey, Dewar, van Fraassen, Weatherall.
6 06 Jul, 16:30 BST More Logic in Philosophy of Science Halvorson (2019) Chapter 8 (Whatever sections you like. Optional, encouraged: read all!)
5 30 Jun, 16:30 BST More Logic in Philosophy of Science Halvorson (2019) Chapter 7 (Whatever sections you like. Optional, encouraged: read all!)
4 23 Jun, 16:30 BST More Logic in Philosophy of Science Halvorson (2019) Chapters 5-6 (Whatever sections you like. Optional, encouraged: read all!)
3 16 Jun, 16:30 BST More Logic in Philosophy of Science Halvorson (2019) Chapters 3-4 Sections 3.6-3.7 and Sections 4.4-4.6 (Optional, encouraged: Read the whole chapters!)
2 09 Jun, 16:30 BST Problem of time redux This meeting wraps up loose threads and offers more open discussion of our 26 May reading on Gryb and Thébault (2016). Optional further reading: Gryb and Thébault (2015) "Time remains".
1 02 Jun, 16:30 BST The Logic in Philosophy of Science Halvorson (2019) Chapter 1 of The logic in philosophy of science, Cambridge University Press, with optional Chapter 2 and Chapter 3; see also the bibliography - With special guest Hans Halvorson. His recommendation: Focus on pgs.1-18 and pgs.24-27; Chapter 2 can be skipped; then skim Chapter 3.
Wk Date Topic Reading
8 26 May, 16:30 BST The hole argument and the problem of time Gryb and Thébault (2016), "Regarding the hole argument and the problem of time" - With special guest Sean Gryb (Bonus: Sean's slides and Klaas' slides).
7 19 May,, 16:30 BST Belot on Symmetry and Equivalence Belot (2013) "Symmetry and Equivalence", in The Oxford Handbook of Philosophy of Physics, Batterman (Ed.), OUP., Bryan to present
6 12 May, 16:30 BST Belot on counting possibilities - wrap-up Belot (2016), "Fifty million Elvis fans can't be wrong"
5 05 May, 16:00 BST Belot on counting possibilities in space and time: physics Belot (2016), "Fifty million Elvis fans can't be wrong", Section 4 to End (Henrique presents) - With special guest Gordon Belot.
4 28 Apr, 16:00 BST Belot on counting possibilities in space and time Belot (2016), "Fifty million Elvis fans can't be wrong", through Section 3 (Bryan presents)
3 21 Apr, 16:00 BST Belot on Symmetry and Gauge Freedom Belot (2003), "Symmetry and gauge freedom" (Jeremy to present - handout)
2 14 Apr, 16:00 BST Belot on Symmetries Belot (2003), "Notes on Symmetries", in Brading and Castellani, Symmetries in Physics: Philosophical Reflections, Cambridge University Press. (Jeremy handout)
1 7 Apr, 16:00 BST Belot on Gauge Belot (1998), "Understanding Electromagnetism" (Jeremy to present - handout)

  

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