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arXiv · 1709.03578

Fermion bag approach to Hamiltonian lattice field theories in continuous time

Emilie Huffman·Shailesh Chandrasekharan
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Abstract

We extend the idea of fermion bags to Hamiltonian lattice field theories in the continuous time formulation. Using a class of models we argue that the temperature is a parameter that splits the fermion dynamics into small spatial regions that can be used to identify fermion bags. Using this idea we construct a continuous time quantum Monte Carlo algorithm and compute critical exponents in the 3d Ising Gross-Neveu universality class using a single flavor of massless Hamiltonian staggered fermions. We find $η$=0.54(6) and $ν$=0.88(2) using lattices up to N=2304 sites. We argue that even sizes up to N=10,000 sites should be accessible with supercomputers available today.

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Emilie Huffman, Shailesh Chandrasekharan. 2017-09-11. Fermion bag approach to Hamiltonian lattice field theories in continuous time. https://doi.org/10.1103/physrevd.96.114502

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