Simulation-based clustering to constrain Modified Gravity theories
Carolina Cuesta-Lazaro
April 2022 - Britgrav
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FORGE Collaboration: Christian Arnold, Benjamin Giblin, Joachim Harnois-Deraps, Yan-Chuan Cai, Cesar Hernandez-Aguayo, Chris Davies, Enrique Paillas, Cheng-Zong Ruan and Baojiu Li
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Space-time
geometetry
Energy content
Adding new degrees of freedom
- To the energy content (dynamic) DARK ENERGY
- To the way space-time geometry reacts to the energy content MODIFIED GRAVITY (FIFTH FORCES)
?
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GRAVITATIONAL ACTIONS
N-BODY SIMULATIONS
LIKELIHOOD
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LARGE SCALE STRUCTURE DATA
DESI,Euclid ...
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GRAVITATIONAL ACTIONS
N-BODY SIMULATIONS
LIKELIHOOD
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LARGE SCALE STRUCTURE DATA
DESI,Euclid ...
DESI
Spectroscopic
30+ million redshifts
Credit: D. Schlegel/Berkeley Lab using data from DESI
EUCLID
Imaging
15,000 square degrees out to redshift z=2
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arxiv:2109.04984
nDGP
Can match expansion to LCDM
Screening mechanisms to pass solar system tests
Do not modify speed of gravitational wave propagation
Need a "cosmological constant"
f(R)
FORGE: F(R)
BRIDGE: nDGP
More models coming soon!
MG-GLAM x100 faster than MG-Arepo
arxiv:2110.00328
arxiv:2110.00566
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arxiv:2109.04984
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2-POINT STATISTICS
arxiv:2109.04984
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Credit: https://cs231n.github.io/convolutional-networks/
FORGE collaboration (in prep)
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Harnois-Deraps et al (in prep)
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Mimicking Euclid
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Environment dependent clustering
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- O(50) N-body simulations -> sub-percent accurate predictions for two point observables -> tight constraints on Modified gravity parameters through a Euclid-like survey
- We can engineer summary statistics that extract more information by exploiting environmental dependencies. But, can we model them to the same accuracy?
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What is the impact of baryons on small scales?
Are there degeneracies with other cosmological parameters that would alter our constraints?
Simulation-based clustering predictions to constrain Modified Gravity theories
By carol cuesta
Simulation-based clustering predictions to constrain Modified Gravity theories
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