24 research outputs found
Sustaining supercooled mixed phase via resonant oscillations of the order parameter
We investigate the dynamics of a first order transition when the order
parameter field undergoes resonant oscillations, driven by a periodically
varying parameter of the free energy. This parameter could be a background
oscillating field as in models of pre-heating after inflation. In the context
of condensed matter systems, it could be temperature , or pressure, external
electric/magnetic field etc. We show that with suitable driving frequency and
amplitude, the system remains in a type of mixed phase, without ever completing
transition to the stable phase, even when the oscillating parameter of the free
energy remains below the corresponding critical value (for example, with
oscillating temperature, always remains below the critical temperature
). This phenomenon may have important implications. In cosmology, it will
imply prolonged mixed phase in a first order transition due to coupling with
background oscillating fields. In condensed matter systems, it will imply that
using oscillating temperature (or, more appropriately, pressure waves) one may
be able to sustain liquids in a mixed phase indefinitely at low temperatures,
without making transition to the frozen phase.Comment: 17 pages, 7 figures, Expanded version with more detail
Smart Multiple Access Topologi Employing Intelligent Physical Layer for addressing the Mobile Node
Clinical utility of MRI biomarkers for identifying NASH patients’ high risk of progression: A multi-center pooled data and meta-analysis
Formation and Collapse of False Vacuum Bubbles in Relativistic Heavy-Ion Collisions
It is possible that under certain situations, in a relativistic heavy-ion
collision, partons may expand out forming a shell like structure. We analyze
the process of hadronization in such a picture for the case when the
quark-hadron transition is of first order, and argue that the inside region of
such a shell must correspond to a supercooled (to ) deconfined vacuum.
Hadrons from that region escape out, leaving a bubble of pure deconfined vacuum
with large vacuum energy. This bubble undergoes relativistic collapse, with
highly Lorentz contracted bubble walls, and may concentrate the entire energy
into extremely small regions. Eventually different portions of bubble wall
collide, with the energy being released in the form of particle production.
Thermalization of this system can lead to very high temperatures. With a
reasonably conservative set of parameters, at LHC, the temperature of the hot
spot can reach as high as 3 GeV, and well above it with more optimistic
parameters. Such a hot spot can leave signals like large partons,
dileptons, and enhanced production of heavy quarks. We also briefly discuss a
speculative possibility where the electroweak symmetry may get restored in the
highly dense region resulting from the decay of the bubble wall via the
phenomenon of non-thermal symmetry restoration (which is usually employed in
models of pre-heating after inflation). If that could happen then the
possibility may arise of observing sphaleron induced baryon number violation in
relativistic heavy-ion collisions.Comment: 32 pages, 9 figures, title changed, discussion added about
equilibration of decay products of bubble wall, discussions of baryon
violation significantly modified, new references added. (Version to appear in
Nucl.Phys.A
Novel WLL Architecture Based on Color Pixel Multiple Access Implemented on a Terrestrial Video Network as the Overlay
Light waves of different wavelengths and frequencies manifest in various colors. Color can be formulated electronically by video processing technologies for the purpose of multimedia, image processing and entertainment. Optoelectronic devices like DWDM use optical signals of various wave lengths for conveying data symbols from one end to other. The big question is: Is it feasible to implement color synthesized by the video systems for the purpose of telecommunications? In this paper we propose the ‘Color Pixel Multiple Access’ scheme for the radio access network and Color Pixel Multiplexing for core network, by implementing electronic color as a tool for addressing and bearing data overhead. The present day video systems that can generate millions of colors, in its electronic form have been utilized to set up a wireless network, serving mobile stations or computers as its nodes. The state of the art Wireless Local Loop deployments are based on the traditional cellular technologies. However there are limitations in terms of intricacy, cost and time to deploy .In this paper, the authors introduce a Wireless Local Loop architecture employing the proposed CPMA technique on existing overlay video/television network. Further we corroborate the advantages.</p