Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fierz relations for Volkov spinors and the simplification of Furry
  picture traces   Transition probability calculations of strong field particle processes in the
Furry picture, typically use fermion Volkov solutions. These solutions have a
relatively complicated spinor due to the interaction of the electron spin with
a strong external field, which in turn leads to unwieldy trace calculations.
The simplification of these calculations would aid theoretical studies of
strong field phenomena such as the predicted resonance behaviour of higher
order Furry picture processes. Here, Fierz transformations of Volkov spinors
are developed and applied to a 1st order and a 2nd order Furry picture process.
Combined with symmetry properties, the techniques presented here are generally
applicable and lead to considerable simplification of Furry picture analytic
calculations.

11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics