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Cosmological magnetic fields from primordial Kerr-Newman black holes
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Implications on cosmology from Dirac neutrino magnetic moments
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de Sitter space decay and cosmological constant relaxation in unimodular gravity with charged membranes
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Improved modeling of the kinematic Sunyaev-Zel’dovich projected-fields signal and its cosmological dependence
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Probing cosmological particle production and pairwise hotspots with deep neural networks
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Role of strange quarks in the D -term and cosmological constant term of the proton
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Recurrent axion stars collapse with dark radiation emission and their cosmological constraints
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Adaptive friend-of-friends algorithm for identifying gravitationally bound cosmological structures
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Cosmological constraints from the Subaru Hyper Suprime-Cam year 1 shear catalogue lensing convergence probability distribution function
Here we utilize the probability distribution function (PDF) of normalized convergence maps reconstructed from the Subaru Hyper Suprime-Cam (HSC) year 1 shear catalogue, in combination with the power spectrum, to measure the matter clustering amplitude S 8 = σ 8 $\sqrt {Ω_{m}/0.3}$. The large-scale structure’s statistical properties are incompletely described by the traditional two-point statistics, motivating our investigation of the PDF—a complementary higher-order statistic. By defining the PDF over the standard-deviation-normalized convergence map, we are able to isolate the non-Gaussian information. We use tailored simulations to compress the data vector and construct a likelihood approximation. We mitigate the impact of survey and astrophysical systematics with cuts on smoothing scales, redshift bins, and data vectors. We find S 8 = $0.860^{+0.066}_{–0.109}$ from the PDF alone and S 8 = 0.798$^{+0.029}_{–0.042}$ from the combination of the PDF and power spectrum (68% confidential level (CL)). The PDF improves the power-spectrum-only constraint by about 10%.
Stasis, stasis, triple stasis: A theoretical study of cosmological stasis
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Unsupervised searches for cosmological parity violation: An investigation with convolutional neural networks
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Relativistic bulk rheology: From neutron star mergers to viscous cosmology
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Displacement field analysis via optimal transport: Multitracer approach to cosmological reconstruction
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Superresolution emulation of large cosmological fields with a 3D conditional diffusion model
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Cosmological dynamics of string theory axion strings
The quantum chromodynamics (QCD) axion may solve the strong CP problem and explain the dark matter (DM) abundance of our Universe. The axion was originally proposed to arise as the pseudo-Nambu-Goldstone boson of global U(1) PQ Peccei-Quinn (PQ) symmetry breaking, but axions also arise generically in string theory as zero modes of higher-dimensional gauge fields. In this work we show that string theory axions behave fundamentally differently from field theory axions in the early Universe. Field theory axions may form axion strings if the PQ phase transition takes place after inflation. In contrast, we show that string theory axions do not generically form axion strings. In special inflationary paradigms, such as D-brane inflation, string theory axion strings may form; however, their tension is parametrically larger than that of field theory axion strings. We then show that such QCD axion strings overproduce the DM abundance for all allowed QCD axion masses and are thus ruled out, except in scenarios with large warping. A loop-hole to this conclusion arises in the axiverse, where an axion string could be composed of multiple different axion mass eigenstates; a heavier eigenstate could collapse the network earlier, allowing for the QCD axion to produce the correct DM abundance and also generating observable gravitational wave signals.