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We formulate a kinetic theory of quantum information scrambling in the context of a paradigmatic model of interacting electrons in the vicinity of a superconducting phase transition. We carefully derive a set of coupled partial differential equations that effectively govern the dynamics of information spreading in generic dimensions. Their solutions show that scrambling propagates at the maximal speed set by the Fermi velocity. At early times, we find exponential growth at a rate set by the inelastic scattering. At late times, we find that scrambling is governed by shock-wave dynamics with traveling waves exhibiting a discontinuity at the boundary of the light cone. Notably, we find perfectly causal dynamics where the solutions do not spill outside of the light cone.
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Electromagnetic Casimir–Polder Interaction for a Conducting Cone
Using the formulation of the electromagnetic Green’s function of a perfectly conducting cone in terms of analytically continued angular momentum, we compute the Casimir–Polder interaction energy of a cone with a polarizable particle. We introduce this formalism by first reviewing the analogous approach for a perfectly conducting wedge, and then demonstrate the calculation through numerical evaluation of the resulting integrals.
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- Award ID(s):
- 2209582
- PAR ID:
- 10504030
- Editor(s):
- Klimchitskaya, Galina L.; Mostepanenko, Vladimir M.
- Publisher / Repository:
- MDPI Physics
- Date Published:
- Journal Name:
- Physics
- Volume:
- 5
- Issue:
- 4
- ISSN:
- 2624-8174
- Page Range / eLocation ID:
- 1003 to 1012
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/physics5040065
