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Full-Text Articles in Physics
Type-1.5 Superconducting State From An Intrinsic Proximity Effect In Two-Band Superconductors, Egor Babaev, Johan Carlstrom, Martin Speight
Type-1.5 Superconducting State From An Intrinsic Proximity Effect In Two-Band Superconductors, Egor Babaev, Johan Carlstrom, Martin Speight
Egor Babaev
We show that in multiband superconductors even small interband proximity effect can lead to a qualitative change in the interaction potential between superconducting vortices by producing long-range intervortex attraction. This type of vortex interaction results in unusual response to low magnetic fields leading to phase separation into domains of a two-component Meissner states and vortex droplets.
A Switch In Retrograde Signaling From Survival To Stress In Rapid Onset Neurodegeneration, Jennifer Ross, Erika L.F Holzbaur, Robert G. Kalb, Karen E. Wallace, Ram Dixit, Goo-Bo Jeong, Eran Perlson
A Switch In Retrograde Signaling From Survival To Stress In Rapid Onset Neurodegeneration, Jennifer Ross, Erika L.F Holzbaur, Robert G. Kalb, Karen E. Wallace, Ram Dixit, Goo-Bo Jeong, Eran Perlson
Jennifer Ross
Retrograde axonal transport of cellular signals driven by dynein is vital for neuronal survival. Mouse models with defects in the retrograde transport machinery, including the Loa mouse (point mutation in dynein) and the Tgdynamitin mouse (overexpression of dynamitin), exhibit mild neurodegenerative disease. Transport defects have also been observed in more rapidly progressive neurodegeneration, such as that observed in the SOD1G93A transgenic mouse model for familial amyotrophic lateral sclerosis (ALS). Here, we test the hypothesis that alterations in retrograde signaling lead to neurodegeneration. In vivo, in vitro, and live-cell imaging motility assays show misregulation of transport and inhibition of retrograde signaling …
Non-Isotropy Of The Cmb Power Spectrum In Single Field Inflation, John Donoghue, Koushik Dutta, Andreas Ross
Non-Isotropy Of The Cmb Power Spectrum In Single Field Inflation, John Donoghue, Koushik Dutta, Andreas Ross
John Donoghue
Contaldi et al. [1] have suggested that an initial period of kinetic energy domination in single field inflation may explain the lack of CMB power at large angular scales. We note that in this situation it is natural that there also be a spatial gradient in the initial value of the inflaton field, and that this can provide a spatial asymmetry in the observed CMB power spectrum, manifest at low multipoles. We investigate the nature of this asymmetry and comment on its relation to possible anomalies at low multipoles.
Gauge Federation As An Alternative To Unification, John Donoghue, Preema Pais
Gauge Federation As An Alternative To Unification, John Donoghue, Preema Pais
John Donoghue
We motivate and explore the possibility that extra SU(N) gauge groups may exist independently of the Standard Model groups, yet not be subgroups of some grand unified group. We study the running of the coupling constants as a potential evidence for a common origin of all the gauge theories. Several different example are displayed. Some of the multiple options involve physics at the TeV scale.
Transitional Probabilities For The Four-State Random Walk On A Lattice In The Presence Of Partially Reflecting Boundaries, Ramakrishna Janaswamy
Transitional Probabilities For The Four-State Random Walk On A Lattice In The Presence Of Partially Reflecting Boundaries, Ramakrishna Janaswamy
Ramakrishna Janaswamy
The four-state random walk (4RW) model, wherein the particle is endowed with two states of spin and two states of directional motion in each space coordinate, permits a stochastic solution of the Schrödinger equation (or the equivalent parabolic equation) without resorting to the usual analytical continuation in complex space of the particle trajectories. Analytical expressions are derived here for the various transitional probabilities in a 4RW by employing generating functions and eigenfunction expansions when the particle moves on a 1+1 space-time lattice with two-point boundary conditions. The most general case of dissimilar boundaries with partially reflecting boundary conditions is treated …
A Percolation-Theoretic Approach To Spin Glass Phase Transitions, Jonathan Machta, C. M. Newman, D. L. Stein
A Percolation-Theoretic Approach To Spin Glass Phase Transitions, Jonathan Machta, C. M. Newman, D. L. Stein
Jonathan Machta
The magnetically ordered, low temperature phase of Ising ferromagnets is manifested within the associated Fortuin—Kasteleyn (FK) random cluster representation by the occurrence of a single positive density percolating cluster. In this paper, we review our recent work on the percolation signature for Ising spin glass ordering — both in the short-range Edwards—Anderson (EA) and infinite-range Sherrington—Kirkpatrick (SK) models — within a tworeplica FK representation and also in the different Chayes—Machta—Redner two-replica graphical representation. Numerical studies of the ±J EA model in dimension three and rigorous results for the SK model are consistent in supporting the conclusion that the signature of …
Strengths And Weaknesses Of Parallel Tempering, Jonathan Machta
Strengths And Weaknesses Of Parallel Tempering, Jonathan Machta
Jonathan Machta
Parallel tempering, also known as replica exchange Monte Carlo, is studied in the context of two simple free-energy landscapes. The first is a double-well potential defined by two macrostates separated by a barrier. The second is a “golf course” potential defined by microstates having two possible energies with exponentially more high-energy states than low-energy states. The equilibration time for replica exchange is analyzed for both systems. For the double-well system, parallel tempering with a number of replicas that scales as the square root of the barrier height yields exponential speedup of the equilibration time. On the other hand, replica exchange …
Comments On The Minimal Vectorial Standard Model, Mohamed M. Anber, Ufuk Aydemir, John Donoghue, Preema Pais
Comments On The Minimal Vectorial Standard Model, Mohamed M. Anber, Ufuk Aydemir, John Donoghue, Preema Pais
John Donoghue
We explore the available parameter space of the minimal vectorial Standard Model. In this theory, the gauge currents are initially vectorial but the Higgs sector produces chiral mass eigenstates, leading to a set of heavy right-handed mirror particles. We describe the phenomenology of the residual parameter space and suggest that the model will be readily tested at the LHC.