16,254 research outputs found
Hydrodynamic Modes of a holographic wave superfluid
In this work we analyze the hydrodynamics of a wave superfluid on its
strongly coupled regime by considering its holographic description. We obtain
the poles of the retarded Green function through the computation of the
quasi-normal modes of the dual AdS black hole background finding diffusive,
pseudo-diffusive and sound modes. For the sound modes we compute the speed of
sound and its attenuation as function of the temperature. For the diffusive and
pseudo-diffusive modes we find that they acquire a non-zero real part at
certain finite momentum.Comment: 16 pag., 6 fig. Reference added. Minor corrections. Version accepted
for publication in JHE
Backreacting p-wave Superconductors
We study the gravitational backreaction of the non-abelian gauge field on the
gravity dual to a 2+1 p-wave superconductor. We observe that as in the
system a second order phase transition exists between a superconducting and a
normal state. Moreover, we conclude that, below the phase transition
temperature the lowest free energy is achieved by the p-wave solution. In
order to probe the solution, we compute the holographic entanglement entropy.
For both and systems the entanglement entropy satisfies an area law.
For any given entangling surface, the p-wave superconductor has lower
entanglement entropy.Comment: Minor Typos corrected, version published in JHE
Vacuum stability conditions of the economical 3-3-1 model from copositivity
By applying copositivity criterion to the scalar potential of the economical
model, we derive necessary and sufficient bounded-from-below conditions
at tree level. Although these are a large number of intricate inequalities for
the dimensionless parameters of the scalar potential, we present general
enlightening relations in this work. Additionally, we use constraints coming
from the minimization of the scalar potential by means of the orbit space
method, the positivity of the squared masses of the extra scalars, the Higgs
boson mass, the gauge boson mass and its mixing angle with the SM
boson in order to further restrict the parameter space of this model.Comment: 22 pages, 7 figures, added text and references. Matches published
versio
One-dimensional compressibility of intermediate non-plastic soil mixtures
The results of high stress, one-dimensional compression testing on intermediate soils are presented. Nevada Sand and silica silt mixtures were subjected to very high vertical stresses (140 MPa) in one-dimensional, monotonic compression. Each soil mixture was tested in a nominally loose condition. A specially designed mold with an integrated sensor array was fabricated to contain the soil during pre-consolidation and loading. The 1-D compression curve was plotted for each mixture in the double-logarithmic void ratio (e), and vertical effective stress (σ’v) space and characteristics of the Limiting Compression Curve (LCC) were identified. Initial and post test grain size distribution curves were plotted. Significant crushing of the soil grains was observed during one-dimensional loading. The influence of factors including initial density, mineralogy, particle shape, particle size, and grain size distribution on compression behavior of intermediate soil mixtures is discussed. Specimen preparation techniques and testing protocol are presented herein
- …