Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The critical geometry of a thermal big bang   We explore the space of scalar-tensor theories containing two
non-conformalmetrics, and find a discontinuity pointing to a "critical"
cosmological solution. Due to the different maximal speeds of propagation for
matter and gravity,the cosmological fluctuations start off inside the horizon
even without inflation, and will more naturally have a thermal origin (since
there is never vacuum domination). The critical model makes an unambiguous,
non-tuned prediction for the spectral index of the scalar fluctuations: $n_S=
0.96478(64)$. Considering also that no gravitational waves are produced, we
have unveiled the most predictive model on offer. The model has a simple
geometrical interpretation as a probe 3-brane embedded in an $EAdS_2\times E_3$
geometry.

19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con