Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The normal phase of an imbalanced Fermi gas   Recent experiments on imbalanced Fermi gases have raised interest in the
physics of an impurity immersed in a Fermi sea, the so-called Fermi polaron. In
this letter, a simple theory is devised to describe dilute Fermi-polaron
ensembles corresponding to the normal phase of an imbalanced Fermi gas. An
exact formula is obtained for the dominant interaction between polarons,
expressed solely in terms of a single polaron parameter. The physics of this
interaction is identified as a signature of the Pauli exclusion principle.

16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
9
The categories of this paper are: nlin