A Hubble diagram (HD) has recently been constructed in the redshift range 0 z 6.5 using a nonlinear relation between the ultraviolet (UV) and X-ray luminosities of quasi stellar objects (QSOs). The Type Ia Supernovae (SN) HD has already provided a high- precision test of cosmological models, but the fact that the QSO distribution extends well beyond the supernova range (z 1.8), in principle provides us with an important complementary diagnostic whose significantly greater leverage in z can impose tighter constraints on the distance versus redshift relationship. In this paper, we therefore per- form an independent test of nine different cosmological models, among which six are expanding, while three are static. Many of these are disfavored by other kinds of obser- vations (including the aforementioned Type Ia SNe). We wish to examine whether the QSO HD confirms or rejects these earlier conclusions. We find that four of these models (Einstein–de Sitter, the Milne universe, the static universe with simple tired light and the static universe with plasma tired light) are excluded at the > 99% C.L. The quasi-steady state model is excluded at > 95% C.L. The remaining four models (ΛCDM/wCDM, the Rh = ct universe, the Friedmann open universe and a static universe with a linear Hubble law) all pass the test.
Cosmological test with the QSO Hubble diagram / López-Corredoira, M.; Melia, F.; Lusso, E.; Risaliti, G.. - In: INTERNATIONAL JOURNAL OF MODERN PHYSICS D. - ISSN 0218-2718. - ELETTRONICO. - 25:(2016), pp. 1650060-1650070. [10.1142/S0218271816500607]
Cosmological test with the QSO Hubble diagram
Lusso, E.;RISALITI, GUIDO
2016
Abstract
A Hubble diagram (HD) has recently been constructed in the redshift range 0 z 6.5 using a nonlinear relation between the ultraviolet (UV) and X-ray luminosities of quasi stellar objects (QSOs). The Type Ia Supernovae (SN) HD has already provided a high- precision test of cosmological models, but the fact that the QSO distribution extends well beyond the supernova range (z 1.8), in principle provides us with an important complementary diagnostic whose significantly greater leverage in z can impose tighter constraints on the distance versus redshift relationship. In this paper, we therefore per- form an independent test of nine different cosmological models, among which six are expanding, while three are static. Many of these are disfavored by other kinds of obser- vations (including the aforementioned Type Ia SNe). We wish to examine whether the QSO HD confirms or rejects these earlier conclusions. We find that four of these models (Einstein–de Sitter, the Milne universe, the static universe with simple tired light and the static universe with plasma tired light) are excluded at the > 99% C.L. The quasi-steady state model is excluded at > 95% C.L. The remaining four models (ΛCDM/wCDM, the Rh = ct universe, the Friedmann open universe and a static universe with a linear Hubble law) all pass the test.I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.