767 citations · 17k across the 373 of their papers we have counts for
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Fluctuations in a Hořava-Lifshitz Bouncing Cosmology
Xian Gao, Yi Wang, Wei Xue +1
Hořava-Lifshitz gravity is a potentially UV complete theory with important implications for the very early universe. In particular, in the presence of spatial curvature it is possi…
Searching for Signatures of Cosmic Superstrings in the CMB
Rebecca J. Danos, Robert H. Brandenberger
Because cosmic superstrings generically form junctions and gauge theoretic strings typically do not, junctions may provide a signature to distinguish between cosmic superstrings an…
Zipping and Unzipping of Cosmic String Loops in Collision
Hassan Firouzjahi, Johanna Karouby, Shahram Khosravi +1
In this paper the collision of two cosmic string loops is studied. After collision junctions are formed and the loops are entangled. We show that after their formation the junction…
Cosmological Perturbations in Hořava-Lifshitz Gravity
Xian Gao, Yi Wang, R. Brandenberger +1
We study cosmological perturbations in Hořava-Lifshitz Gravity. We consider scalar metric fluctuations about a homogeneous and isotropic space-time. Starting from the most general…
Processing of Cosmological Perturbations in a Cyclic Cosmology
Robert H. Brandenberger
The evolution of the spectrum of cosmological fluctuations from one cycle to the next is studied. It is pointed out that each cycle leads to a reddening of the spectrum. This opens…
Non-Thermal Production of WIMPs, Cosmic Excesses and -rays from the Galactic Center
Xiao-Jun Bi, Robert Brandenberger, Paolo Gondolo +3
In this paper we propose a dark matter model and study aspects of its phenomenology. Our model is based on a new dark matter sector with a U(1)' gauge symmetry plus a discrete symm…
Matter Bounce in Horava-Lifshitz Cosmology
Robert Brandenberger
Horava-Lifshitz gravity, a recent proposal for a UV-complete renormalizable gravity theory, may lead to a bouncing cosmology. In this note we argue that Horava-Lifshitz cosmology m…
Constraints on Models with a Break in the Primordial Power Spectrum
Hong Li, Jun-Qing Xia, Robert Brandenberger +1
One of the characteristics of the "Matter Bounce" scenario, an alternative to cosmological inflation for producing a scale-invariant spectrum of primordial adiabatic fluctuations o…
Thermal Fluctuations and Bouncing Cosmologies
Yi-Fu Cai, Wei Xue, Robert Brandenberger +1
We study the conditions under which thermal fluctuations generated in the contracting phase of a non-singular bouncing cosmology can lead to a scale-invariant spectrum of cosmologi…
The Trans-Planckian Problem for Inflationary Cosmology Revisited
Robert Brandenberger, Xinmin Zhang
We consider an inflationary universe model in which the phase of accelerated expansion was preceded by a non-singular bounce and a period of contraction which involves a phase of d…
Non-Gaussianity in a Matter Bounce
Yi-Fu Cai, Wei Xue, Robert Brandenberger +1
A nonsingular bouncing cosmology in which the scales of interest today exit the Hubble radius in a matter-dominated contracting phase yields an alternative to inflation for produci…
Alternatives to Cosmological Inflation
Robert H. Brandenberger
The inflationary paradigm, although very successful phenomenologically, suffers from several conceptual problems which motivate the search for alternative scenarios of early univer…
Cosmic Ray Positrons from Cosmic Strings
Robert Brandenberger, Yi-Fu Cai, Wei Xue +1
We study the spectrum of cosmic ray positrons produced by a scaling distribution of non-superconducting cosmic strings. In this scenario, the positrons are produced from the jets w…