Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Conformal Gravity: Dark Matter and Dark Energy   This short review examines recent progress in understanding dark matter, dark
energy, and galactic halos using theory that departs minimally from standard
particle physics and cosmology. Strict conformal symmetry (local Weyl scaling
covariance), postulated for all elementary massless fields, retains standard
fermion and gauge boson theory but modifies Einstein-Hilbert general relativity
and the Higgs scalar field model, with no new physical fields. Subgalactic
phenomenology is retained. Without invoking dark matter, conformal gravity and
a conformal Higgs model fit empirical data on galactic rotational velocities,
galactic halos, and Hubble expansion including dark energy.

4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
1
The categories of this paper are: cs
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas