Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Monte Carlo simulations on the Lefschetz thimble: taming the sign
  problem   We present the first practical Monte Carlo calculations of the recently
proposed Lefschetz thimble formulation of quantum field theories. Our results
provide strong evidence that the numerical sign problem that afflicts Monte
Carlo calculations of models with complex actions can be softened significantly
by changing the domain of integration to the Lefschetz thimble or
approximations thereof. We study the interacting complex scalar field theory
(relativistic Bose gas) in lattices of size up to 8^4 using a computationally
inexpensive approximation of the Lefschetz thimble. Our results are in
excellent agreement with known results. We show that - at least in the case of
the relativistic Bose gas - the thimble can be systematically approached and
the remaining residual phase leads to a much more tractable sign problem (if at
all) than the original formulation. This is especially encouraging in view of
the wide applicability - in principle - of our method to quantum field theories
with a sign problem. We believe that this opens up new possibilities for
accurate Monte Carlo calculations in strongly interacting systems of sizes much
larger that previously possible.

2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph