13,886 research outputs found
Detecting crystal symmetry fractionalization from the ground state: Application to spin liquids on the kagome lattice
In quantum spin liquid states, the fractionalized spinon excitations can
carry fractional crystal symmetry quantum numbers, and this symmetry
fractionalization distinguishes different topologically ordered spin liquid
states. In this work we propose a simple way to detect signatures of such
crystal symmetry fractionalizations from the crystal symmetry representations
of the ground state wave function. We demonstrate our method on projected
spin liquid wave functions on the kagome lattice, and show that
it can be used to classify generic wave functions. Particularly our method can
be used to distinguish several proposed candidates of spin liquid
states on the kagome lattice.Comment: main text: 6 pages, 1 figure. supplemental material: 8 pages, 2
figures. Added a few references and the journal referenc
Anomalous Crystal Symmetry Fractionalization on the Surface of Topological Crystalline Insulators
The surface of a three-dimensional topological electron system often hosts
symmetry-protected gapless surface states. With the effect of electron
interactions, these surface states can be gapped out without symmetry breaking
by a surface topological order, in which the anyon excitations carry anomalous
symmetry fractionalization that cannot be realized in a genuine two-dimensional
system. We show that for a mirror-symmetry-protected topological crystalline
insulator with mirror Chern number , its surface can be gapped out by an
anomalous topological order, where all anyons carry
mirror-symmetry fractionalization . The identification of such
anomalous crystalline symmetry fractionalization implies that in a
two-dimensional spin liquid the vison excitation cannot carry
if the spinon carries or a half-integer spin.Comment: 6+8 pages, 2 figures. v2: added a new section in the supplemental
material, the journal reference and some other change
Excitation function of initial temperature of heavy flavor quarkonium emission source in high energy collisions
The transverse momentum spectra of , , and produced in proton-proton (+), proton-antiproton
(+), proton-lead (+Pb), gold-gold (Au+Au), and lead-lead (Pb+Pb)
collisions over a wide energy range are analyzed by the (two-component) Erlang
distribution, the Hagedorn function (the inverse power-law), and the
Tsallis-Levy function. The initial temperature is obtained from the color
string percolation model due to the fit by the (two-component) Erlang
distribution in the framework of multisource thermal model. The excitation
functions of some parameters such as the mean transverse momentum and initial
temperature increase from dozens of GeV to above 10 TeV. The mean transverse
momentum and initial temperature decrease (increase slightly or do not change
obviously) with the increase of rapidity (centrality). Meanwhile, the mean
transverse momentum of is larger than that of
and , and the initial temperature for
emission is higher than that for and emission, which shows
a mass-dependent behavior.Comment: 26 pages, 12 figures. Advances in High Energy Physics, accepte
Loops, sign structures and emergent Fermi statistics in three-dimensional quantum dimer models
We introduce and study three-dimensional quantum dimer models with positive
resonance terms. We demonstrate that their ground state wave functions exhibit
a nonlocal sign structure that can be exactly formulated in terms of loops, and
as a direct consequence, monomer excitations obey Fermi statistics. The sign
structure and Fermi statistics in these "signful" quantum dimer models can be
naturally described by a parton construction, which becomes exact at the
solvable point.Comment: 9 pages, 12 figure
Causal holographic information does not satisfy the linearized quantum focusing condition
The Hubeny-Rangamani causal holographic information (CHI) defined by a region
of a holographic quantum field theory (QFT) is a modern version of the idea
that the area of event horizons might be related to an entropy. Here the event
horizon lives in a dual gravitational bulk theory with Newton's constant
, and the relation involves a factor of . The fact
that CHI is bounded below by the von Neumann entropy suggests that CHI is
coarse-grained. Its properties could thus differ markedly from those of . In
particular, recent results imply that when holographic QFTs are
perturbatively coupled to -dimensional gravity, the combined system
satisfies the so-called quantum focusing condition (QFC) at leading order in
the new gravitational coupling when the QFT entropy is taken to be that
of von Neumann. However, by studying states dual to spherical bulk (anti--de
Sitter) Schwarschild black holes in the conformal frame for which the boundary
is a -dimensional de Sitter space, we find the QFC defined by CHI is
violated even when perturbing about a Killing horizon and using a single null
congruence. Since it is known that a generalized second law (GSL) holds in this
context, our work demonstrates that the QFC is not required in order for an
entropy, or an entropy-like quantity, to satisfy such a GSL.Comment: 12 pages, 3 figures; v2: modifications to address referee comment
Comparing a few distributions of transverse momenta in high energy collisions
Transverse momentum spectra of particles produced in high energy collisions
are very important due to their relations to the excitation degree of
interacting system. To describe the transverse momentum spectra, one can use
more than one probability density functions of transverse momenta, which are
simply called the functions or distributions of transverse momenta in some
cases. In this paper, a few distributions of transverse momenta in high energy
collisions are compared with each other in terms of plots to show some
quantitative differences. Meanwhile, in the framework of Tsallis statistics,
the distributions of momentum components, transverse momenta, rapidities, and
pasudorapidities are obtained according to the analytical and Monte Carlo
methods. These analyses are useful to understand carefully different
distributions in high energy collisions.Comment: 11 pages, 7 figures. Results in Physics, Accepte
An Internal Observability Estimate for Stochastic Hyperbolic Equations
This paper is addressed to establishing an internal observability estimate
for some linear stochastic hyperbolic equations. The key is to establish a new
global Carleman estimate for forward stochastic hyperbolic equations in the
-space. Different from the deterministic case, a delicate analysis of the
adaptedness for some stochastic processes is required in the stochastic
setting
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