Deviation from Gaussianity in the cosmic microwave background temperature fluctuations
| dc.creator | Bernui, Armando | |
| dc.creator | Tsallis, Constantino | |
| dc.creator | Villela, Thyrso | |
| dc.date | 2007-03-28 | |
| dc.date.accessioned | 2026-07-07T10:21:56Z | |
| dc.date.available | 2026-07-07T10:21:56Z | |
| dc.description | Recent measurements of the temperature fluctuations of the cosmic microwave background (CMB) radiation from the WMAP satellite provide indication of a non-Gaussian behavior. Although the observed feature is small, it is detectable and analyzable. Indeed, the temperature distribution P^{CMB}(Delta T) of these data can be quite well fitted by the anomalous probability distribution emerging within nonextensive statistical mechanics, based on the entropy S_q = k (1 - \int dx [P(x)]^q)/(q - 1) (where in the limit case q -> 1 we obtain the Boltzmann-Gibbs entropy S_1 = - k \int dx P(x) ln[P(x)]). For the CMB frequencies analysed, ν= 40.7, 60.8, and 93.5 GHz, P^{CMB}(Delta T) is well described by P_q(Delta T) \propto 1/[1 + (q-1) B(ν) (Delta T)^2]^{1/(q-1)}, with q = 1.04 \pm 0.01, the strongest non-Gaussian contribution coming from the South-East sector of the celestial sphere. Moreover, Monte Carlo simulations exclude, at the 99% confidence level, P_1(Delta T) \propto e^{- B(ν) (Delta T)^2} to fit the three-year WMAP data. | |
| dc.description | 6 pages, 1 figure | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0703708 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0703708 | |
| dc.identifier | Europhys.Lett.78:19001,2007 | |
| dc.identifier | doi:10.1209/0295-5075/78/19001 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/175343 | |
| dc.subject | Astrophysics | |
| dc.subject | Statistical Mechanics | |
| dc.title | Deviation from Gaussianity in the cosmic microwave background temperature fluctuations | |
| dc.type | text |