Physics / research
Cosmological models confronted with observations
Translate cosmological models into distance, lensing, clustering, and microwave-background observables, tracking degeneracies and limits of inference.
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Module 01 research
Cosmological models confronted with observations
Translate cosmological models into distance, lensing, clustering, and microwave-background observables, tracking degeneracies and limits of inference.
- 01
Distance measures and distance duality
Translate angles, fluxes, and redshifts into explicitly defined FLRW distances, then test the assumptions behind reciprocity.
28 min - 02
Standard candles and supernova Hubble diagrams
Build a standardized supernova distance modulus while tracking absolute calibration, correlated errors, and selection.
29 min - 03
Baryon acoustic oscillations as standard rulers
Infer distance-to-ruler ratios from transverse and radial BAO while separating late-time geometry from early-time calibration.
29 min - 04
Cosmic microwave background acoustic peaks
Connect coherent photon–baryon oscillations to angular spectra while distinguishing acoustic geometry, transfer physics, and cosmic variance.
30 min - 05
CMB polarization and E–B mode decomposition
Distinguish local Stokes measurements from spatial E/B patterns, including rotation conventions and foreground or lensing contamination.
30 min - 06
Weak gravitational lensing and cosmic shear
Relate local image distortion to projected matter while tracking reduced shear, redshift kernels, and mass-sheet degeneracy.
30 min - 07
Galaxy bias and redshift-space distortions
Derive a linear anisotropic clustering prediction and expose its bias, velocity, amplitude, and survey-window assumptions.
29 min - 08
Cosmological likelihoods and parameter degeneracy
Construct correlated-data likelihoods with nuisance parameters, finite-covariance caveats, and a transparent calibration-floor example.
30 min - 09
Dark-energy equations of state and model tests
Translate a specified equation of state into expansion and acceleration, then separate a parametrized fit from a physical discovery.
30 min - 10
Cosmological tensions and systematic cross-checks
Quantify a dated one-parameter discrepancy and design cross-checks that distinguish correlated errors, model dependence, and new-physics proposals.
31 min