Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Work Required for Selective Quantum Measurement   In quantum mechanics, we define the measuring system $M$ in a selective
measurement by two conditions. Firstly, when we define the measured system $S$
as the system in which the non-selective measurement part acts, $M$ is
independent from the measured system $S$ as a quantum system in the sense that
any time-dependent process in the total system $S+M$ is divisible into parts
for $S$ and $M$. Secondly, when we can separate $S$ and $M$ from each other
without changing the unitary equivalence class of the state of $S$ from that
obtained by the partial trace of $M$, the eigenstate selection in the selective
measurement cannot be realized. In order for such a system $M$ to exist, we
show that in one selective measurement of an observable of a quantum system
$S_0$ of particles in $S$, there exists a negative entropy transfer from $M$ to
$S$ that can be directly transformed into an amount of Helmholtz free energy of
$k_BT$ where $T$ is the thermodynamic temperature of the system $S$.
Equivalently, an extra amount of work, $k_BT$, is required to be done by the
system $M$.

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The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th