Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Proof for an upper bound in fixed-node Monte Carlo for lattice fermions   We justify a recently proposed prescription for performing Green Function
Monte Carlo calculations on systems of lattice fermions, by which one is able
to avoid the sign problem. We generalize the prescription such that it can also
be used for problems with hopping terms of different signs. We prove that the
effective Hamiltonian, used in this method, leads to an upper bound for the
ground-state energy of the real Hamiltonian, and we illustrate the
effectiveness of the method on small systems.

30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn