Physics Frontiers – Détails, épisodes et analyse

Jim talks with Bruna Shinohara of CMC Microsystems. Quantum computing and machine learning are both currently making huge strides.  So it is not strange that people are trying to use quantum computing for machine learning.

Jim talks with Alex Jurgens about Maxwellian ratchets, automata that are similar to Maxwell's Demon.  They talk about their implications for information processing and entropy.

http://frontiers.physicsfm.com/77

Jim talks with Gilad Gour of the University of Toronto about quantum resource theories.  These are theories of largish systems that describe the relationships between possible states by the different levels of resources required for each.  By using resources, a system can move from one state to another.  This results in a partial order where between two states there could be two different states inaccessible to one another. Although (usually) these coalesce into an order based on a single property of thermodynamically-sized systems, the entropy, a few do not.

Show Notes: http://frontiers.physicsfm.com/68

Jim talks with Matthew R. Edwards about his theory of Optical Gravity.  This is a Le Sage model of gravity based on graviton filiments.

Show Notes: http://frontiers.physicsfm.com/67

Jim 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 

Jim talks with Michal Eckstein of the Copernicus Institute for Interdisciplinary Studies about how two different kinds of ordering, chronological and causal, give rise to a robust idea of time.  Additionally, we discuss the Experiment Paradox, a generalization of other measurement-type paradoxes in physics.

Show Notes: http://frontiers.physicsfm.com/65

Jim talks with Blake Stacey about recent attempts to replace Born's rule.  Born's rule is the principle used in quantum mechanics that associates quantum states to the probability of measurement.  There has been a recent interest in Quantum Foundations to try to find a less arbitrary rationale for this procedure.  

Show Notes: http://frontiers.physicsfm.com/64

Jim talks with Blake Stacey about Gleason's Theorem, a foundational topic in the foundations of quantum mechanics.  Gleason's theorem gives us a set of characteristic states for a measurement and the probability rule associated measuring them.  This is the first part of the interview.  The second part will discuss recent attempts to replace the Born Rule.

Show Notes: http://frontiers.physicsfm.com/63

Jim and Randy talk about how special relativity might be amended to incorporate a minimum length scale.  Such scales are common in quantum gravity theories, and in the limit where both QM and GR are less important, QG should induce first order corrections to SR.  We then talk about how these corrections seem to lead to unreasonable paradoxes.

Show Notes: http://frontiers.physicsfm.com/62

Jim and Randy talk about alternatives to black holes without event horizons or singularities.

Show Notes: http://frontiers.physicsfm.com/61