Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pair creation by time-dependent electric fields: Analytic solutions   Exact analytical solutions are presented for the time evolution of the
density of pairs produced in the QED vacuum by a uniform electric field that is
adiabatically switched on starting at minus infinity. Pair production is
described by the Dirac-Heisenberg-Wigner function introduced before [Phys. Rev.
D 44, 1825 (1991)]. The explicit solution is obtained by an extension of the
method of the spinorial decomposition to deal with a time-varying electric
field. The main result of this work is that the pair density is an analytic
function of the field strength; it can be expanded into a convergent power
series. Therefore, the essential singularity present in the Schwinger formula
is to be attributed to the infinitely long duration of the process of pair
creation by a time-independent field.

36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph