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arXiv · 2609.34402

Discontinuity of Continuum Fermion Dynamics

Oliver Siebert
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Abstract

We study the Heisenberg dynamics of continuum fermions in $\IR^d$ interacting through a pair potential. For a large class of nonconstant pair potentials and under suitable assumptions on the dispersion relation and external potential, we prove that the dynamics fails to be pointwise-norm continuous even on the gauge-invariant CAR algebra. An automatic-continuity argument then shows that neither the CAR algebra nor its gauge-invariant subalgebra is invariant under the dynamics, with non-invariance occurring for almost all times.

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Oliver Siebert. 2026-09-28. Discontinuity of Continuum Fermion Dynamics. https://arxiv.org/abs/2609.34402

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