相关论文: Cosmological Constraints on Theories with Large Ex…

It has been long discussed that cosmic rays may contain signals of dark matter. In the last couple of years an anomaly of cosmic-ray positrons has drawn a lot of attentions, and recently an excess in cosmic-ray anti-proton has been reported…

We review the implications of modern higher-dimensional theories of gravity for astrophysics and cosmology. In particular, we discuss the latest developments of space-time-matter theory in connection with dark matter, particle dynamics and…

In models with large extra dimensions, where quantum gravity effects become strong at the TeV scale, the rho-parameter can receive large contributions from one-loop diagrams involving exchange of multiple graviton and dilaton states. These…

The turn-around radii of the galaxy groups show the imprint of a long battle between their self-gravitational forces and the accelerating space. The standard $\Lambda$CDM cosmology based on the general relativity (GR) predicts the existence…

We review a set of the possible ways to constrain extended gravity models at Galaxy clusters scales (the regime of dark energy explanations and comparison with $\Lambda CDM$), for black hole shadows, gravitational wave astronomy, binary…

We investigate the cosmological perturbations around FLRW solutions to non- linear massive gravity with a new effective coupling to matter proposed recently. Unlike the case with minimal matter coupling, all five degrees of freedom in the…

TThe detection of gravitational waves from merging binary black holes has led to a bound on the mass of a hypothetical massive carrier of the gravitational interaction predicted by some modified gravity theories (a massive graviton, for…

We describe new no-go theorems for producing four-dimensional accelerating universes from warped dimensional reduction. The new theorems improve upon previous results by including dynamical extra dimensions and by treating four-dimensional…

Many extensions of the Standard Model predict large numbers of additional unstable particles whose decays in the early universe are tightly constrained by observational data. For example, the decays of such particles can alter the ratios of…

We investigate f(R) theories of gravity within the Palatini approach and show how one can determine the expansion history, H(a), for an arbitrary choice of f(R). As an example, we consider cosmological constraints on such theories arising…

We consider the cosmology that results if our observable universe is a 3-brane in a higher dimensional universe. In particular, we focus on the case where our 3-brane is located at the $Z_2$ symmetry fixed plane of a $Z_2$ symmetric…

In order to resolve the hierarchy problem, large extra dimensions have been introduced, and it has been suggested that the size of extra dimensions is sub-millimeter. On the other hand, we assume in this paper that the cosmological constant…

The constraints on the radion evolution in the Universal Extra Dimension (UED) model from Cosmic Microwave Background (CMB) and Type Ia supernovae (SNe Ia) data are studied. In the UED model, where both the gravity and standard model fields…

We argue that theories in which supersymmetry breaking originates at low energies often contain scalar particles that mediate coherent gravitational strength forces at distances less than a cm. We estimate the strength and range of these…

We reexamine the constraints on universal extra dimensional models arising from the inclusive radiative Bbar -> X_s gamma decay. We take into account the leading order contributions due to the exchange of Kaluza-Klein modes as well as the…

In the context of f(R) theories of gravity, we study the cosmological evolution of scalar perturbations by using a completely general procedure. We find that the exact fourth-order differential equation for the matter density perturbations…

We use measurements of the growth of cosmic structure, as inferred from the observed evolution of the X-ray luminosity function (XLF) of galaxy clusters, to constrain departures from General Relativity (GR) on cosmological scales. We employ…

The problem of Majorana neutrino mass generated in Arkani-Hamed--Dimopoulos-Dvali model with n extra spatial dimensions is discussed. Taking into account constraints on neutrino masses coming from cosmological observations, it is possible…

We reconsider the constraints on Universal Extra Dimensions (UED) models arising from precision electroweak data. We take into account the subleading contributions from new physics (expressed in terms of the X,Y ... variables), as well as…

We study the cosmological implications of gravity models which break diffeomorphisms (Diff) invariance down to transverse diffeomorphisms (TDiff). We start from the most general gravitational action involving up to quadratic terms in…