Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Competing bounds on the present-day time variation of fundamental
  constants   We compare the sensitivity of a recent bound on time variation of the fine
structure constant from optical clocks with bounds on time varying fundamental
constants from atomic clocks sensitive to the electron-to-proton mass ratio,
from radioactive decay rates in meteorites, and from the Oklo natural reactor.
Tests of the Weak Equivalence Principle also lead to comparable bounds on
present variations of constants. The "winner in sensitivity" depends on what
relations exist between the variations of different couplings in the standard
model of particle physics, which may arise from the unification of gauge
interactions. WEP tests are currently the most sensitive within unified
scenarios. A detection of time variation in atomic clocks would favour
dynamical dark energy and put strong constraints on the dynamics of a
cosmological scalar field.

7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an