Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Performance analysis of a physically constructed orthogonal
  representation of imaginary-time Green's function   The imaginary-time Green's function is a building block of various numerical
methods for correlated electron systems. Recently, it was shown that a
model-independent compact orthogonal representation of the Green's function can
be constructed by decomposing its spectral representation. We investigate the
performance of this so-called \textit{intermedaite representation} (IR) from
several points of view. First, for two simple models, we study the number of
coefficients necessary to achieve a given tolerance in expanding the Green's
function. We show that the number of coefficients grows only as $O(\log \beta)$
for fermions, and converges to a constant for bosons as temperature $T=1/\beta$
decreases. Second, we show that this remarkable feature is ascribed to the
properties of the physically constructed basis functions. The fermionic basis
functions have features in the spectrum whose width is scaled as $O(T)$, which
are consistent with the low-$T$ properties of quasiparticles in a Fermi liquid
state. On the other hand, the properties of the bosonic basis functions are
consistent with those of spin/orbital susceptibilities at low $T$. These
results demonstrate the potential wide application of the IR to calculations of
correlated systems.

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The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs
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The categories of this paper are: math-ph
10
The categories of this paper are: q-bio