Carol's favourite topics

 

Carolina Cuesta-Lazaro

IAIFI Fellow (CfA/MIT)

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Observe galaxies

4

Pick your favourite analytical likelihood (Gaussian!)

5

Compute ~1Million times to get posterior

Constrain cosmology 101

Missing Information!

Perturbation Theory inaccurate / hard to compute

Is it always true?

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Work on your analytical theory

2

Count pairs as a function of distance

+ Galaxy formation

+ Observational systematics (Cut-sky, Fiber collisions)

+ Lightcone, Redshift Space Distortions....

Forward Model

N-body simulations

Observations

 SIMBIG arXiv:2211.00723

Credit: Siddharth Mishra-Sharma

We can simulate the observable Universe, we just need hydrodynamical simulations

25 \, h^{-1}\mathrm{Mpc}
10^{10} - 10^{11} M_\odot

Super massive black hole seeding in dark matter halos

BH feedback impacts galactic scales

Black holes can also growth through mergers

they can even teleport!

Can ML bridge the scale gap to help us carry out full physics simulations across all scales?

Subresolution models

(Credit: http://tigress-web.princeton.edu/~changgoo/)

Resolving star formation

We can't model galaxy formation, how do we make our models robust?

Robust Summarisation

\mathcal{L} = I(S(x_\mathrm{sims})|\theta_\mathrm{sims}) + \blue{\lambda p_\mathrm{sims}(S(x_\mathrm{obs}))}
S:

Summariser (neural net)

(\theta_\mathrm{sims}, x_\mathrm{sims})
x_\mathrm{obs}
\mathcal{L} = I(S(x_\mathrm{sims})|\theta_\mathrm{sims})

Increase the evidence of the observations

Sims misspecified

deck

By carol cuesta