Probing cosmological parameters with the CMB: forecasts from Monte Carlo simulations
By L. Perotto, Julien Lesgourgues, S. Hannestad, H. Tu, Y. Wong. 2006
215 citations recorded by the source corpus.
The Fisher matrix formalism has in recent times become the standard method for predicting the precision with which various cosmological parameters can be extracted from future data. This approach is fast and generally returns accurate estimates for the parameter errors when the individual parameter likelihoods approximate a Gaussian distribution. However, where Gaussianity is not respected (due, for instance, to strong parameter degeneracies), the Fisher matrix formalism loses its reliability. In this paper, we compare the results of the Fisher matrix approach with those from Monte Carlo simulations. The latter method is based on the publicly available CosmoMC code, but uses synthetic realizations of data sets anticipated for future experiments. We focus on prospective cosmic microwave background (CMB) data from the Planck satellite, with or without CMB lensing information, and its implications for a minimal cosmological scenario with eight parameters and an extended model with eleven parameters. We show that in many cases, the projected sensitivities from the Fisher matrix and the Monte Carlo methods differ significantly, particularly for models with many parameters. Sensitivities to the neutrino mass and the dark matter fraction are especially susceptible to change.
Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics
View Paper: https://www.semanticscholar.org/paper/e7f30662b5fcc29bf4b177a2ee1aa4ba4da1a9ec
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Astronomy and Astrophysics
In Nuclear and High Energy Physics
Citations in the corpus
- Refined bounds on MeV-scale thermal dark sectors from BBN and the CMB (2019, unknown): “The stepsizes used are of order ∆θi ∼ σ(θi), as to output a more reliable estimate of the confidence level [168].”
- Double-Disk Dark Matter (2013, result): “Further analysis of Planck data in combination with other experiments may help to clarify the number of relativistic species at the time of the CMB [57–59].”
- Thermalisation of light sterile neutrinos in the early universe (2012, methodology): “The upcoming measurement of δNeff by Planck will confirm or rule out the existence of such extra radiation with high precision [64, 65].”
- Neutrino Mass in Cosmology: Status and Prospects (2011, methodology): “ lensing of the CMB Light from the last scattering surface can also be lensed by the foreground matter [86]. Indeed, with Planck one can hope to probe P m with sensitivity of 0:1 eV via CMB lensing [69,87,88]. The main advantage of CMB lensing over galaxy lensing is that because the source lies at ”
- COrE (Cosmic Origins Explorer) A White Paper (2011, background): “While future distance-indicator measurements may help, to be conservative here we consider only constraints from COrE alone in a joint analysis of the unlensed temperature and E-mode polarization and the reconstructed deflection field, following [31].”
- Neutrino Mass from Cosmology (2012, methodology): “r constraints on P(k;z) at such high redshifts. In the very close future, signicant improvements on the neutrino mass bounds will be triggered by the Planck CMB satellite. The forecasts presented in [76] predict a neutrino mass sensitivity of ˙(M ) ˘0:1 eV from Planck alone, using the lensing extrac”
- Phases of new physics in the CMB (2015, methodology): “Our goal is to extend these results in two ways: (i) to include Yp and Nfluid to identify more clearly the types of BSM physics we might be sensitive to and (ii) to perform a full likelihood analysis (rather than a Fisher forecast) to ensure that degeneracies are treated correctly (see [47] for a di”