Zobrazeno 1 - 10
of 521
pro vyhledávání: '"Heavens, A. F."'
We develop extreme data compression for use in Bayesian model comparison via the MOPED algorithm, as well as more general score compression. We find that Bayes factors from data compressed with the MOPED algorithm are identical to those from their un
Externí odkaz:
http://arxiv.org/abs/2306.15998
Autor:
Sellentin, E., Loureiro, A., Whiteway, L., Lafaurie, J. S., Balan, S. T., Olamaie, M., Jaffe, A. H., Heavens, A. F.
Inference in cosmology often starts with noisy observations of random fields on the celestial sphere, such as maps of the microwave background radiation, continuous maps of cosmic structure in different wavelengths, or maps of point tracers of the co
Externí odkaz:
http://arxiv.org/abs/2305.16134
Publikováno v:
The Open Journal of Astrophysics, Vol 6, 2023
We present a field-based signal extraction of weak lensing from noisy observations on the curved and masked sky. We test the analysis on a simulated Euclid-like survey, using a Euclid-like mask and noise level. To make optimal use of the information
Externí odkaz:
http://arxiv.org/abs/2210.13260
The 3D matter power spectrum, $P_{\delta}(k,z)$ is a fundamental quantity in the analysis of cosmological data such as large-scale structure, 21cm observations, and weak lensing. Existing computer models (Boltzmann codes) such as CLASS can provide it
Externí odkaz:
http://arxiv.org/abs/2105.02256
Autor:
Jimenez, Raul, Heavens, Alan F.
Publikováno v:
Monthly Notices of the Royal Astronomical Society Letters. 498, L93, 2020
In the light of the discovery of numerous (almost) dark galaxies from the ALFALAFA and LITTLE THINGS surveys, we revisit the predictions of Jimenez et al. 1997, based on the Toomre stability of rapidly-spinning gas disks. We have updated the predicti
Externí odkaz:
http://arxiv.org/abs/2005.11798
In this paper, we propose a Gaussian Process (GP) emulator for the calculation of a) tomographic weak lensing band-power spectra, and b) coefficients of summary data massively compressed with the MOPED algorithm. In the former case cosmological param
Externí odkaz:
http://arxiv.org/abs/2005.06551
Autor:
Leclercq, Florent, Faure, Baptiste, Lavaux, Guilhem, Wandelt, Benjamin D., Jaffe, Andrew H., Heavens, Alan F., Percival, Will J., Noûs, Camille
Publikováno v:
A&A 639, A91 (2020)
Existing cosmological simulation methods lack a high degree of parallelism due to the long-range nature of the gravitational force, which limits the size of simulations that can be run at high resolution. To solve this problem, we propose a new, perf
Externí odkaz:
http://arxiv.org/abs/2003.04925
Autor:
Jones, Daniel M., Heavens, Alan F.
Future cosmological galaxy surveys such as the Large Synoptic Survey Telescope (LSST) will photometrically observe very large numbers of galaxies. Without spectroscopy, the redshifts required for the analysis of these data will need to be inferred us
Externí odkaz:
http://arxiv.org/abs/1907.10572
Autor:
Jimenez, Raul, Maartens, Roy, Khalifeh, Ali Rida, Caldwell, Robert R., Heavens, Alan F., Verde, Licia
Publikováno v:
JCAP05(2019)048
We propose a method to probe the homogeneity of a general universe, without assuming symmetry. We show that isotropy can be tested at remote locations on the past lightcone by comparing the line-of-sight and transverse expansion rates, using the time
Externí odkaz:
http://arxiv.org/abs/1902.11298
We use Dataflow Engines (DFE) to construct an efficient Wiener filter of noisy and incomplete image data, and to quickly draw probabilistic samples of the compatible true underlying images from the Wiener posterior. Dataflow computing is a powerful a
Externí odkaz:
http://arxiv.org/abs/1810.02821