Exploring cosmological expansion parametrizations with the gold SnIa data set
Φόρτωση...
Ημερομηνία
Συγγραφείς
Lazkoz, R.
Nesseris, S.
Perivolaropoulos, L.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Journal of Cosmology and Astroparticle Physics
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
We use the SnIa gold data set to compare LCDM (lambda cold dark matter) with ten representative parametrizations of the recent Hubble expansion history H(z). For the comparison we use two statistical tests: the usual X(min)(2) and a statistical test that we call the p-test which depends on both the value of X(min)(2) and the number n of parametrization parameters. The p-test measures the confidence level to which the parameter values corresponding to LCDM are excluded from the viewpoint of the parametrization tested. For example, for a linear equation of state parametrization w(z) = w(0) + w(1)z, the LCDM parameter values (w(0) = -1, w(1) = 0) are excluded at the 75% confidence level. We use a. at prior and Omega(0)m = 0.3. All parametrizations tested are consistent with the gold data set at their best fit. According to both statistical tests, the worst fits among the ten parametrizations correspond to the Chaplygin gas, the brane world and the Cardassian parametrizations. The best fit is achieved by oscillating parametrizations which can exclude the parameter values corresponding to LCDM at the 85% confidence level. Even though this level of significance does not provide a statistically significant exclusion of LCDM ( it is less than 2 sigma) and does not by itself constitute conclusive evidence for oscillations in the cosmological expansion, when combined with similar independent recent evidence for oscillations coming from the cosmic microwave background and matter power spectra, it becomes an issue worthy of further investigation.
Περιγραφή
Λέξεις-κλειδιά
dark energy theory, cosmological constant experiments, gravity, cosmology of theories beyond the sm, dark energy density, equation-of-state, chaplygin-gas, cardassian expansion, galactic poles, phantom matter, scalar field, universe, constraints, supernova
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000233746000001
http://iopscience.iop.org/1475-7516/2005/11/010/pdf/1475-7516_2005_11_010.pdf
http://iopscience.iop.org/1475-7516/2005/11/010/pdf/1475-7516_2005_11_010.pdf
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών και Τεχνολογιών. Τμήμα Βιολογικών Εφαρμογών και Τεχνολογιών