119111044
Finsler geometric perspective on the bulk flow in the universe
Abstract Astronomical observations showed that there may exist a bulk flow with peculiar velocities in the universe, which contradicts with the ΛCDM model. The bulk flow reveals that the observational universe is anisotropic at large scales. In fact, a more reliable observation on the anisotropy of spacetime comes from the CMB power spectra. The WMAP and Planck satellites both show that there is a hemispherical power asymmetry at large-angular scales. In this Letter, we propose a “wind” scenario to the bulk flow (or the anisotropy of spacetime). Under the influence of the “wind”, the spacetime metric could become a Finsler structure. By resolving the null geodesic equation, we obtain the modified luminosity distance, which has a dipolar form at the leading order. Thus, the “wind” describes well the bulk flow. In addition, we perform a least- χ 2 fit to the data of type Ia supernovae (SNe Ia) in the Union2.1 compilation. The peculiar velocity of the bulk flow has an upper limit v bulk ≲ 4000 km / s , which is compatible with all the existing observational values.
118432739
An inflationary scenario taking into account of possible dark energy effects in the early universe
We investigate the possible effect of cosmological-constant type dark energy during the inflation period of the early universe. This is accommodated by a new dispersion relation in de Sitter space. The modified inflation model of a minimally coupled scalar field is still able to yield an observation-compatible scale-invariant primordial spectrum, simultaneously having the potential to generate a spectrum with lower power at large scales. A qualitative match to the WMAP 7-year data is presented. We obtain an ΩΛ of the same order of that in the Λ-CDM model. Possible relations between the de Sitter scenario and Doubly Special Relativity (DSR) are also discussed.
118324583
A study of meson-meson potential in the chiral quark model
An effective potential in a meson-meson system is discussed based on the SU(3) chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is employed to study the bound state problem of ω, which is related to the new resonance of f0(1810) observed in BES II very recently.