Related papers: Lifetimes of light stringy states
An approach towards a statistical survey of four dimensional supersymmetric vacua in the string theory landscape is described and illustrated with three examples of ensembles of intersecting D-brane models. The question whether it is…
We present a supersymmetric model of space-time foam with two stacks of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that represent quantum fluctuations in the space-time…
It was recently suggested that the discrepancy between two methods of measuring the lifetime of the neutron may be a result of an unseen decay mode into a dark matter particle which is almost degenerate with the neutron. We explore the…
At the final stage of unstable D-brane decay in the effective field theory approach, all energy and momentum of the initial state are taken up by two types of fluids, known as string fluid and tachyon matter. In this note, we compare motion…
The mediator particle between the Standard Model sector and a hidden sector might have a long lifetime to show the observable displaced vertices in experiments. Considering a fermionic dark matter model in which the hidden sector is…
We study the dissipative decay of states with a doubly occupied site in a two-electron Hubbard model, known as doublons. For the environment we consider charge and current noise which are modelled as a bosonic heat bath that couples to the…
Dark Matter is essential for structure formation in the late Universe so it must be stable on cosmological time scales. But how stable exactly? Only assuming decays into relativistic particles, we report an otherwise model independent bound…
In the context of brane world scenario, cosmic superstrings can be formed in D-brane annihilation at the end of the brane inflationary era. The cosmic superstring network has a scaling solution and the characteristic scale of the network is…
We investigate the cosmological evolution of an interacting phantom energy model in which the phantom field has interaction with the dark matter. We discuss the existence and stability of scaling solutions for two types of specific…
Topological phases of matter remain a focus of interest due to their unique properties -- fractionalisation, ground state degeneracy, and exotic excitations. While some of these properties can occur in systems of free fermions, their…
This paper explores the possibility of the existence of dark photons within the visible light range and provides evidence for their existence through a thought experiment. A new model of dark photons is established based on extensive…
We consider the inhomogeneous decay of an unstable D-brane of bosonic string theory in a linear dilaton background in a light-cone frame. At the lowest level, the dynamical equation that describes this process is a generalisation (that…
We discuss a model of non perturbative decay of dark energy into hot and cold dark matter. This model provides a mechanism from the field theory to realize the energy transfer from dark energy into dark matter, which is the requirement to…
Recently, the CDMS experiment has reported the possible first direct-detection of dark matter. We update the direct-detection constraints for neutralino dark matter arising in a realistic string model constructed from intersecting D6-branes…
By employing D6-branes intersecting at angles in $D = 4$ type IIA strings, we construct {\em four stack string GUT models} (PS-I class), that contain at low energy {\em exactly the three generation Standard model} with no extra matter…
The mechanism of recombination of intersecting D-branes is investigated within the framework of effective tachyon field theory. We regard the branes as the kink-type tachyon condensed states and use the effective two-tachyon Lagrangian to…
We discuss novel properties of the string field and the Open String Field Theory action arising in a system with multiple D-branes, then use the level truncation scheme to study marginal deformations and tachyon condensation in a system…
We calculate the pair-annihilation cross section of real scalar singlet dark matter into two mono-energetic photons. We derive constraints on the theory parameter space from the Fermi limits on gamma-ray lines, and we compare with current…
One possible probe to physics beyond the standard model is to look for scalar bilinears, which couple to two fermions of the standard model. We point out that the scalar bilinears allow new diagrams contributing to the neutrinoless double…
We consider extensions of the standard model based on open strings ending on D-branes, in which gauge bosons and their associated gauginos exist as strings attached to stacks of D-branes, and chiral matter exists as strings stretching…