1,070 research outputs found
Finite density QCD with chiral invariant four-fermion interactions
A mean field analysis of finite density QCD is presented including the
effects of additional chiral invariant four-fermion interactions. A lattice
regularization is used with N_f=4 flavors of staggered fermions. The use of the
four-fermion coupling as an improved extrapolation parameter over the bare
quark mass in Monte Carlo simulations is discussed. Particular attention is
given to the structure of the phase diagram and the order of the chiral phase
transition. At zero gauge coupling, the model reduces to a Nambu-Jona-Lasinio
model. In this limit the chiral phase transition is found to be second-order
near the zero-density critical point and otherwise first-order. In the strong
gauge coupling limit a first-order chiral phase transition is found. In this
limit the additional four-fermion interactions do not qualitatively change the
physics. The results agree with previous studies of QCD as the four-fermion
coupling vanishes.Comment: 18 pages, RevTeX, 12 figures using epsf.st
Prophetic Imagination in the Light of Narratology and Disability Studies in Isaiah 40–48
Analyzes Isaiah 40–48 as a single literary work through levels of speakers (frame and subordinate) with implications for its construction of divine potency and communication
A Kingdom of Priests and Its Earthen Altars in Exodus 19–24
Argues that, reversing the trope of subjects visiting the magnificent, the Elohistic history has Yahweh interested in the simplest, flimsiest altars only, which he will visit when and where he is invited to do so. The implication rules out temple-altars and temples for their royal sponsorship
The Face of God and the Etiquette of Eye-Contact: Visitation, Pilgrimage, and Prophetic Vision in Ancient Israelite and Early Jewish Imagination
Uses social poetics to analyze talk in the Bible of looking at Yahweh's fac
Nodal inequalities on surfaces
Given a Laplace eigenfunction on a surface, we study the distribution of its
extrema on the nodal domains. It is classically known that the absolute value
of the eigenfunction is asymptotically bounded by the 4-th root of the
eigenvalue. It turns out that the number of nodal domains where the
eigenfunction has an extremum of such order, remains bounded as the eigenvalue
tends to infinity.
We also observe that certain restrictions on the distribution of nodal
extrema and a version of the Courant nodal domain theorem are valid for a
rather wide class of functions on surfaces. These restrictions follow from a
bound in the spirit of Kronrod and Yomdin on the average number of connected
components of level sets.Comment: 14 pages, added a discussion of a connection with the
Alexandrov-Backelman-Pucci inequalit
On the divine clockwork: the spectral gap for the correspondence limit of the Nelson diffusion generator for the atomic elliptic state
The correspondence limit of the atomic elliptic state in three dimensions is
discussed in terms of Nelson's stochastic mechanics. In previous work we have
shown that this approach leads to a limiting Nelson diffusion and here we
discuss in detail the invariant measure for this process and show that it is
concentrated on the Kepler ellipse in the plane z=0. We then show that the
limiting Nelson diffusion generator has a spectral gap; thereby proving that in
the infinite time limit the density for the limiting Nelson diffusion will
converge to its invariant measure. We also include a summary of the Cheeger and
Poincare inequalities both of which are used in our proof of the existence of
the spectral gap.Comment: 30 pages, 5 figures, submitted to J. Math. Phy
On Ptolemaic metric simplicial complexes
We show that under certain mild conditions, a metric simplicial complex which
satisfies the Ptolemy inequality is a CAT(0) space. Ptolemy's inequality is
closely related to inversions of metric spaces. For a large class of metric
simplicial complexes, we characterize those which are isometric to Euclidean
space in terms of metric inversions.Comment: 13 page
Implementation of arbitrary real-valued correlation filters for the shadow-casting incoherent correlator
International audienceWe describe an incoherent correlator, based on the shadow-casting principle, that is able to implement any real-valued linear correlation filter. The correlation filter and the input image are displayed on commercial liquid-crystal television ~LCTV! panels. Although it cannot handle high-resolution images, the incoherent correlator is lensless, compact, low cost, and uses a white-light source. A bipolar technique is devised to represent any linear filter, computed from a single reference image or composite, in the correlator. We demonstrate experimentally the efficiency of the design in the case of optimal trade-off ~OT! filters and optimal trade-off synthetic discriminant function ~OT-SDF! filter
Spectral Evolution of the Universe
We derive the evolution equations for the spectra of the Universe.
Here "spectra" means the eigenvalues of the Laplacian defined on a space,
which contain the geometrical information on the space.
These equations are expected to be useful to analyze the evolution of the
geometrical structures of the Universe.
As an application, we investigate the time evolution of the spectral distance
between two Universes that are very close to each other; it is the first
necessary step for the detailed analysis of the model-fitting problem in
cosmology with the spectral scheme.
We find out a universal formula for the spectral distance between two very
close Universes, which turns out to be independent of the detailed form of the
distance nor the gravity theory. Then we investigate its time evolution with
the help of the evolution equations we derive.
We also formulate the criteria for a good cosmological model in terms of the
spectral distance.Comment: To appear in Phys. Rev.
Strings and Aharonov-Bohm Effect in Abelian Higgs Model
We investigate numerically the properties of the Abrikosov-Nielsen-Olesen
strings in 4D abelian Higgs model. The fractal dimension D_f of the vortex
strings was found to be large in the Coulomb phase and it is close to 2 in the
Higgs phase. We also show that the Wilson loop for non-integer charges is
correlated with the linking number of the vortex string world sheets and the
test particle world trajectory. We find that this topological (Aharonov-Bohm)
interaction gives the main contribution to the Wilson loop quantum average for
non-integer test charges in the vicinity of the Coulomb-Higgs phase transition.Comment: 8 pages, LaTeX, 5 EPS-figures, uses epsf.st
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