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arXiv · 2412.00924

Electrons Lost in Phase Space

Tomer Ravid
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Abstract

I review the formalism of patch bosonization of Fermi surfaces, with a focus on the problem of a two-dimensional metal at a quantum critical point. I argue that this formalism is fundamentally inapplicable to the problem, except in synthetic limits. One such limit is the small-$N$ limit, which was already discussed in early studies of the problem; a similar but slightly less unphysical large-$N$ limit is proposed. I show that it is at least formally possible to construct perturbative expansions around these synthetic limits. However, I argue that nonperturbative effects become important when $N\sim1$.

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Tomer Ravid. 2024-12-01. Electrons Lost in Phase Space. https://arxiv.org/abs/2412.00924

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