Schwinger model on an interval: analytic results and DMRG
- URL: http://arxiv.org/abs/2210.00297v2
- Date: Wed, 22 Mar 2023 07:44:56 GMT
- Title: Schwinger model on an interval: analytic results and DMRG
- Authors: Takuya Okuda
- Abstract summary: We show that the conventional Gauss law constraint commonly used in simulations induces a strong boundary effect on the charge density.
We obtain by bosonization a number of exact analytic results for local observables in the massless Schwinger model.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Quantum electrodynamics in $1+1$ dimensions (Schwinger model) on an interval
admits lattice discretization with a finite-dimensional Hilbert space, and is
often used as a testbed for quantum and tensor network simulations. In this
work we clarify the precise mapping between the boundary conditions in the
continuum and lattice theories. In particular we show that the conventional
Gauss law constraint commonly used in simulations induces a strong boundary
effect on the charge density, reflecting the appearance of fractionalized
charges. Further, we obtain by bosonization a number of exact analytic results
for local observables in the massless Schwinger model. We compare these
analytic results with the simulation results obtained by the density matrix
renormalization group (DMRG) method and find excellent agreements.
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