Zobrazeno 1 - 10
of 10
pro vyhledávání: '"Hayley J. Macpherson"'
Publikováno v:
The Open Journal of Astrophysics, Vol 7 (2024)
Anisotropies in the distance-redshift relation of cosmological sources are expected due to large-scale inhomogeneities in the local Universe. When the observed sources are tracing a large-scale matter flow in a general spacetime geometry, the distanc
Externí odkaz:
https://doaj.org/article/3b9f105884bf4ca8ba67b768e3caf721
Autor:
Hayley J. Macpherson
Publikováno v:
The Astrophysical Journal, Vol 970, Iss 2, p 111 (2024)
We study the impact of nearby inhomogeneities on an observer’s inference of the Hubble constant. Large-scale structures induce a dependence of cosmological parameters on observer position as well as an anisotropic variance of those parameters acros
Externí odkaz:
https://doaj.org/article/b66757f41bee45159efdaef2d191679a
Publikováno v:
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society, 2023, 519 (4), pp.4841-4855. ⟨10.1093/mnras/stac3812⟩
Monthly Notices of the Royal Astronomical Society, 2023, 519 (4), pp.4841-4855. ⟨10.1093/mnras/stac3812⟩
The cosmological principle asserts that the Universe looks spatially homogeneous and isotropic on sufficiently large scales. Given the fundamental implications of the cosmological principle, it is important to empirically test its validity on various
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::be173eafd1d93504669524895eeadb6c
Second-order tensor modes induced by nonlinear gravity are a key component of the cosmological background of gravitational waves. A detection of this background would allow us to probe the primordial power spectrum at otherwise inaccessible scales. U
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5ca580619e46d4ee5916bc707e7e084c
http://arxiv.org/abs/2111.09163
http://arxiv.org/abs/2111.09163
Autor:
Hayley J. Macpherson, Asta Heinesen
Publikováno v:
Physical Review D. 104
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3302825e911e5a17cf7ddf7e7eb01fba
https://doi.org/10.1103/physrevd.104.109901
https://doi.org/10.1103/physrevd.104.109901
We perform large-scale cosmological simulations that solve Einstein's equations directly via numerical relativity. Starting with initial conditions sampled from the cosmic microwave background, we track the emergence of a cosmic web without the need
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::62d21c6a83e7f740673698280eb5fdd2
Publikováno v:
Physical Review D. 95
We perform three-dimensional numerical relativity simulations of homogeneous and inhomogeneous expanding spacetimes, with a view towards quantifying non-linear effects from cosmological inhomogeneities. We demonstrate fourth-order convergence with er
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c7c02db91f724bd0fff81229dfdaa04d
https://doi.org/10.1103/physrevd.95.064028
https://doi.org/10.1103/physrevd.95.064028
Publikováno v:
The Astrophysical Journal. 865:L4
In a fully inhomogeneous, anisotropic cosmological simulation performed by solving Einstein's equations with numerical relativity, we find a local measurement of the effective Hubble parameter differs by less than 1\% compared to the global value. Th
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0d1ada958a4653d923e01cdc325d0b29
https://doi.org/10.3847/2041-8213/aadf8c
https://doi.org/10.3847/2041-8213/aadf8c
Publikováno v:
Astrophysical Journal Letters; 9/20/2018, Vol. 865 Issue 1, p1-1, 1p
Autor:
Hayley J. Macpherson, Marco Bruni, Cristian Barrera-Hinojosa, Julian Adamek, Baojiu Li, James B. Mertens
Publikováno v:
Adamek, J, Barrera-Hinojosa, C, Bruni, M, Li, B, MacPherson, H J & Mertens, J B 2020, ' Numerical solutions to Einstein's equations in a shearing-dust universe : A code comparison ', Classical and Quantum Gravity, vol. 37, no. 15, 154001 . https://doi.org/10.1088/1361-6382/ab939b
Classical and Quantum Gravity
Classical and Quantum Gravity
A number of codes for general-relativistic simulations of cosmological structure formation have been developed in recent years. Here we demonstrate that a sample of these codes produce consistent results beyond the Newtonian regime. We simulate solut
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0f5d5af11c6a2df34c33f8dd5da88fc5