Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Space-time dispersion of graphene conductivity   We present an analytic calculation of the conductivity of pure graphene as a
function of frequency $\omega $, wave-vector $k$, and temperature for the range
where the energies related to all these parameters are small in comparison with
the band parameter $\gamma =3$ eV. The simple asymptotic expressions are given
in various limiting cases. For instance, the conductivity for $kv_{0}\ll T\ll
\omega $ is equal to $\sigma (\omega, k)=e^{2}/4\hbar $ and independent of the
band structure parameters $\gamma $ and $v_{0}$. Our results are also used to
explain the known dependence of the graphite conductivity on temperature and
pressure.

3
The categories of this paper are: physics
1
The categories of this paper are: cs
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph