Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improved constraint on primordial gravitational waves in light of the
  Hubble tension and BICEP/Keck   The Hubble tension that the standard $\Lambda$CDM model is suffering from can
be resolved with pre-recombination early dark energy. We present the first
constraint on the tensor-to-scalar ratio $r$ in corresponding
Hubble-tension-free cosmologies using the most recent BICEP/Keck cosmic
microwave background (CMB) B-mode polarization data. We find, combining
BICEP/Keck with Planck18 CMB and baryon acoustic oscillation data, that the
models with larger Hubble constant $H_0$ will have tighter upper bound on $r$,
and resolution $H_0\sim73$ km/s/Mpc of the Hubble tension tightens the upper
bound to $r<0.028\ (95\%\text{C.L.})$, $25\%$ tighter than the $\Lambda$CDM
constraint $r<0.036$. We clarify the origin of this tightening bound.

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The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex