Search Publications
Probing Space-Time in the Solar System:. from Cassini to Bepicolombo
Iess, Luciano; Asmar, Sami
Spacecraft radio science techniques can be used for precision solar system tests of relativistic gravity, as was demonstrated by the measurement of the Doppler shift of radio signals with the Cassini mission. Similar experiments are planned for the BepiColombo mission to Mercury. Recent theoretical developments based on string theory and inflation…
Do Recent Supernovae ia Observations Tend to Rule Out all the Cosmologies?
Vishwakarma, Ram Gopal
Dark energy and the accelerated expansion of the universe have been the direct predictions of the distant supernovae Ia observations which are also supported, indirectly, by the observations of the CMB anisotropies, gravitational lensing and the studies of galaxy clusters. Today these results are accommodated in what has become the concordance cos…
Light Superconducting Strings in the Galaxy
Ferrer, Francesc; Vachaspati, Tanmay
Observations of the Milky Way by the SPI/INTEGRAL satellite have confirmed the presence of a strong 511 keV gamma ray line emission from the bulge, which requires an intense source of positrons in the galactic center. These observations are hard to account for by conventional astrophysical scenarios, whereas other proposals, such as light DM, face…
Constraints on Simplified Quartessence Cosmology from the Latest Observational Data
Wu, Puxun; Dong, Sumei
The simplified generalized Chaplygin gas (GCG) model as a candidate of UDME is studied in this paper. By using the latest 162 ESSENCE type Ia supernovae (Sne Ia) data, 30 high red shift Sne Ia data and the distance ratio from z = 0.35 to z = 1089 (the red shift of decoupling), we obtain Ω k = 0.076-0.077+0.093 and …