Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Maximum efficiency of steady-state heat engines at arbitrary power   We discuss the efficiency of a heat engine operating in a nonequilibrium
steady state maintained by two heat reservoirs. Within the general framework of
linear irreversible thermodynamics we derive a universal upper bound on the
efficiency of the engine operating at arbitrary fixed power. Furthermore, we
show that a slight decrease of the power below its maximal value can lead to a
significant gain in efficiency. The presented analysis yields the exact
expression for this gain and the corresponding upper bound.

13
The categories of this paper are: quant-ph
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The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph