Shows
Physics FrontiersThe Limit of General Relativity with James Owen WeatherallJim talks with James Owen Weatherall about his work on viewing general relativity as an effective field theory and where it should give way to another theory. General relativity does a very good job of describing the world we see in astronomical observations, but certain results, e.g. singularities, and certain limits, e.g. the Planck scale, hint that there should be another theory that supersedes it. Jim Weatherall argues that this is in a high curvature regime.Show Notes: http://frontiers.physicsfm.com/66 2022-06-2630 min
PhysicsFMCounting UnviersesJim goes on a diatribe about infinities and the multiverse.2021-10-2532 min
PhysicsFMEntropy v. EntropyIn this episode, I discuss a paper talking about the relationship between physical entropy and information-theoretic entropy in the context of quantum communication.2020-06-1921 minPhysicsFMThe Machine in the GhostThis week, I talk about the fate of the universe in Bohmian Cosmology. Specifically, how Torres, Fabris, and Piattella use the de Broglie-Bohm interpretation of quantum mechanics to modify the Wheeler-De Witt equation in the an accelerating universe.Show Notes: http://papers.physicsfm.com/32020-05-1424 minPhysicsFMItty Bitty PhysicsI talk about a paper by John Archibald Wheeler, "Information, Physics, Quantum: The Search for Links."Show Notes: http://papers.physicsfm.com/22020-04-3032 minPhysicsFMThe Quantum BookieI talk about Quantum Bayesianism, the extension of the Bayesian interpretation of probability to quantum mechanics, through the work of Christopher Fuchs.Show Notes: http://papers.physicsfm.com/12020-04-1929 minPhysicsFMPhysicsFM - Intermission - Quantum MetaphysicsJim and Randy discuss the ways in which we interpret the wavefunction, quantum indeterminancy, and other strange things that happen in quantum mechanics -- going through nine classes of interpretation and what they mean about the underlying reasons for quantum mechanical behavior.2017-03-041h 28PhysicsFMPhysicsFM - Quantum Paradoxes 9 - Quantum CatsRandy and Jim discuss the implications of Schroedinger's Cat. In light of the measurement problem, in light of the collapse of the wave function, how can you understand what is happening to a quantum mechanical system?2015-08-061h 05
PhysicsFMPhysicsFM - Quantum Paradoxes 8 - Measurement and CompensationJim and Randy discuss how "compensation forces" allow measurements of non-canonical variables without the difficulties discovered in the previous episode. They also discuss why some very important concepts of classical physics -- velocity and the electric field -- are not canonical.2015-07-0342 minPhysicsFMPhysicsFM - Quantum Paradoxes 7 - Quantum Measurements - Jim Rantschler and Randy MorrisonRandy and Jim talk about measurements of quantum systems, specifically in terms of a paradox involving the measurement of the velocity. This includes a long discussion of the von Neumann model of quantum mechanics.2015-04-2236 minPhysicsFMPhysicsFM - Quantum Paradoxes 6 - Nonlocality and Causality - Randy Morrison and Jim RantschlerJim and Randy discuss Aharonov and Rohrlich's suggestion that quantum mechanics should be formulated in terms of axioms based upon its physical peculiarities -- Nonlocality and Causality.2015-03-2552 minPhysicsFMPhysicsFM - Quantum Paradoxes 5 - Modular Variables - Randy Morrison and Jim RantschlerRandy and Jim discuss modular variables and how looking at an infinite number of slits in a diffraction grating can better elucidate the process of quantum interference than the two-slit experiment.2015-02-2149 minPhysicsFMPhysicsFM - Quantum Paradoxes 4 - Phases and Gauges - Randy Morrison and Jim RantschlerJim and Randy talk about two paradoxes that help describe the Aharonov-Bohm effect. This requires an excursion into the gauge invariance of the vector potential of electrodynamics -- and how that gauge has real effects in quantum theory, even though it did not in classical physics.2015-01-2452 minPhysicsFMPhysicsFM - Quantum Paradoxes 3 - Is Quantum Theory Complete? - Randy Morrison and Jim RantschlerRandy and Jim discuss the completeness of quantum theory via the EPR Paradox, Bell's Theorem, and the Aspect Experiment and they discuss the Block Universe and David Bohm's interpretation of quantum mechanics.2014-12-2031 minPhysicsFMPhysicsFM - Quantum Paradoxes 2 - How to Weigh a Quantum - Randy Morrison and Jim RantschlerJim and Randy discuss the meaning of consistency, black body radiation, the Compton effect, uncertainty relationships, single-slit diffraction, and the clock in a box paradox.2014-11-2138 minPhysicsFMPhysicsFM - Quantum Paradoxes 1 - The Uses of Paradox - Randy Morrison and Jim RantschlerRandy and Jim discuss paradoxes in general, some quantum effects, what paradoxes mean to physics, and the twin paradox.2014-10-2141 min