Small cosmological signatures from multi-brane models (2008)
Contaldi, Carlo R., Nicholson, Gavin, Stoica, Horace
We analyse the signatures of brane inflation models with moduli stabilisation. These are hybrid inflation models with a non-trivial field-space metric which can induce complex trajectories for the...
Dynamics of F/D networks: the role of bound states (2008)
Sakellariadou, Mairi, Stoica, Horace
We study, via numerical experiments, the role of bound states in the evolution of cosmic superstring networks, being composed by p F-strings, q D-strings and (p,q) bound states. We find robust...
Constraints on Brane Inflation and Cosmic Strings (2007)
Battye, Richard A., Garbrecht, Bjorn, Moss, Adam, Stoica, Horace
By considering simple, but representative, models of brane inflation from a single brane-antibrane pair in the slow roll regime, we provide constraints on the parameters of the theory imposed by...
Kaluza-Klein relics from warped reheating (2007)
Berndsen, Aaron, Cline, James M., Stoica, Horace
It has been suggested that after brane-antibrane inflation in a Klebanov-Strassler (KS) warped throat, metastable Kaluza-Klein (KK) excitations can be formed due to nearly-conserved angular momenta...
Brane Decay and Defect Formation (2007)
Topological defects are generically expected to form in models of brane inflation. Brane-anti-brane annihilation provides a way to gracefully end inflation, and the dynamics of the tachyon field...
Numerical experiments with p F- and q D-strings: the formation of (p,q) bound states (2007)
Rajantie, Arttu, Sakellariadou, Mairi, Stoica, Horace
We investigate the behaviour of (p,q) string networks, focusing on two aspects: (1) modelling more realistic (p,q) string networks than the Z_N networks used so far and (2) investigating the effect...
13th International Symposium on Particles, Strings and Cosmology (2006)
Rajantie, Arttu, Contaldi, Carlo, Dauncey, Paul, Stoica, Horace
Defect Formation with Bulk Fields (2006)
It has recently been realized that brane-antibrane annihilation (a possible explanation for ending inflation) may result in defect formation, due to the dynamics of the tachyon field. Studies of this...
Multibrane Inflation and Dynamical Flattening of the Inflaton Potential (2005)
Cline, James M., Stoica, Horace
We investigate the problem of fine tuning of the potential in the KKLMMT warped flux compactification scenario for brane-antibrane inflation in Type IIB string theory. We argue for the importance of...
Constraining the New Aether: Gravitational Cherenkov Radiation (2005)
Elliott, Joshua W., Moore, Guy D., Stoica, Horace
We study the simplest concrete theory for spontaneous Lorentz violation, the ``New Aether Theory'' of Jacobson and Mattingly, which is a vector-tensor gravitational theory with a fixed-modulus...
Overproduction of cosmic superstrings (2004)
Barnaby, Neil, Berndsen, Aaron, Cline, James M., Stoica, Horace
We show that the naive application of the Kibble mechanism seriously underestimates the initial density of cosmic superstrings that can be formed during the annihilation of D-branes in the early...
Inter-brane Interactions in Compact Spaces and Brane Inflation (2003)
Shandera, Sarah, Shlaer, Benjamin, Stoica, Horace, Tye, S. -H. Henry
It was pointed out that brane-anti-brane inflation without warped geometry is not viable due to compactification effects (in the simplified scenario where the inflaton is decoupled from the...
The Production, Spectrum and Evolution of Cosmic Strings in Brane Inflation (2003)
Jones, Nicholas T., Stoica, Horace, Tye, S. -H. Henry
Brane inflation in superstring theory predicts that cosmic strings (but not domain walls or monopoles) are produced towards the end of the inflationary epoch. Here, we discuss the production, the...
Brane Interaction as the Origin of Inflation (2002)
Jones, Nicholas, Stoica, Horace, Tye, S. -H. Henry
We reanalyze brane inflation with brane-brane interactions at an angle, which include the special case of brane-anti-brane interaction. If nature is described by a stringy realization of the brane...
Comment on 4D Lorentz invariance violations in the brane-world (2001)
The brane-world scenario offers the possibility for signals to travel outside our visible universe and reenter it. We find the condition for a signal emitted from the brane to return to the brane. We...
Particle Horizon and Warped Phenomenology (2001)
Stoica, Horace, Tye, S. -H. Henry, Wasserman, Ira
Giant resonances of gravity Kaluza-Klein modes (with tensor couplings) in high energy collisions are expected in the Randall-Sundrum orbifold model that incorporates a plausible solution to the...
A Brane World Perspective on the Cosmological Constant and the Hierarchy Problems (2000)
Flanagan, Eanna, Jones, Nicholas, Stoica, Horace, Tye, S. -H. Henry, Wasserman, Ira
We elaborate on the recently proposed static brane world scenario, where the effective 4-D cosmological constant is exponentially small when parallel 3-branes are far apart. We extend this result to...
Cosmology in the Randall-Sundrum Brane World Scenario (2000)
Stoica, Horace, Tye, S. -H. Henry, Wasserman, Ira
The cosmology of the Randall-Sundrum scenario for a positive tension brane in a 5-D Universe with localized gravity has been studied extensively recently. Here we extend it to more general...