15,229 research outputs found
Ultra-low-frequency electromagnetic waves as signals and special counterparts of gravitational waves (from binary mergers) having tensorial and possible nontensorial polarizations
Gravitational waves (GWs, from binary merger) interacting with super-strong
magnetic fields of the neutron star (in the same binary system), would lead to
perturbed electromagnetic waves [EMWs, in the same frequencies of these GWs,
partially in the ultra-low-frequency (ULF) band for the EMWs]. Such perturbed
ULF-EMWs are not only the signals, but also a new type of special EM
counterparts of the GWs. Here, generation of the perturbed ULF-EMWs is
investigated for the first time, and the strengths of their magnetic components
are estimated to be around 10^{-12}Tesla to 10^{-17}Tesla (in fISCO) at the
Earth for various cases [not including the influence of interstellar medium
(ISM)].The components with higher frequencies of the ULF-EMWs (e.g., especially
produced by the GWs of the post-merger stage) above 1.8kHz (typical plasma
frequency around solar system in the Milky way), could propagate through the
ISM from the source until the Earth, and the perturbed ULF-EMWs will be
reprocessed before they arrived at the Earth due to the ISM. Also, the
waveforms of the perturbed ULF-EMWs will be modified into shapes different but
related to the waveforms of the GWs, by the amplification process during the
binary mergers which could amplify the magnetic fields into 10^{12}Tesla or
even higher. Specific connection relationships between the polarizations of the
perturbed ULF-EMWs and the polarizations (tensorial and possible nontensorial)
of the GWs of binary mergers, are also addressed here. Characteristic
properties of the perturbed ULF-EMWs (which would bring us some different new
information of fundamental properties of the gravity and Universe) will be very
helpful for extracting the signals from background noise for possible
observations in the future.Comment: 16 pages, 6 figure
Counting Multiplicities in a Hypersurface over a Number Field
We fix a counting function of multiplicities of algebraic points in a
projective hypersurface over a number field, and take the sum over all
algebraic points of bounded height and fixed degree. An upper bound for the sum
with respect to this counting function will be given in terms of the degree of
the hypersurface, the dimension of the singular locus, the upper bounds of
height, and the degree of the field of definition.Comment: 23 page
A twisted -Neumann problem and Toeplitz -tuples from singularity theory
A twisted -Neumann problem associated to a singularity
is established. By constructing the connection to the
Koszul complex for toeplitz -tuples on Bergman spaces
, we can solve this -Neumann problem. Moreover, we
can compute the cohomology of the holomorphic Koszul complex
explicitlyComment: 20 page
On the L2-Hodge theory of Landau-Ginzburg models
Let X be a non-compact Calabi-Yau manifold and f be a holomorphic function on
X with compact critical locus. We introduce the notion of f-twisted Sobolev
spaces for the pair (X,f) and prove the corresponding Hodge-to-de Rham
degeneration property via L2-Hodge theoretical methods when f satisfies an
asymptotic condition of strongly ellipticity. This leads to a Frobenius
manifold via the Barannikov-Kontsevich construction, unifying the
Landau-Ginzburg and Calabi-Yau geometry. Our construction can be viewed as a
generalization of K.Saito's higher residue and primitive form theory for
isolated singularities. As an application, we construct Frobenius manifolds for
orbifold Landau-Ginzburg B-models which admit crepant resolutions.Comment: 41 pages, comments are welcom
Stability of Steady Solutions to Reaction-Hyperbolic Systems for Axonal Transport
This paper is concerned with the stability of steady solutions to
initial-boundary-value problems of reaction-hyperbolic systems for axonal
transport. Under proper structural assumptions, we clarify the relaxation
structure of the reaction-hyperbolic systems and show the time-asymptotic
stability of steady solutions or relaxation boundary-layers
Improving spin-based noise sensing by adaptive measurements
Localized spins in the solid state are attracting widespread attention as
highly sensitive quantum sensors with nanoscale spatial resolution and
fascinating applications. Recently, adaptive measurements were used to improve
the dynamic range for spin-based sensing of deterministic Hamiltonian
parameters. Here we explore a very different direction -- spin-based adaptive
sensing of random noises. First, we identify distinguishing features for the
sensing of magnetic noises compared with the estimation of deterministic
magnetic fields, such as the different dependences on the spin decoherence, the
different optimal measurement schemes, the absence of the modulo-2\pi phase
ambiguity, and the crucial role of adaptive measurement. Second, we perform
numerical simulations that demonstrate significant speed up of the
characterization of the spin decoherence time via adaptive measurements. This
paves the way towards adaptive noise sensing and coherence protection.Comment: 13 pages, 7 figure
Simulating the Chiral Magnetic Wave in a Box System
The chiral magnetic wave from the interplay between the chiral magnetic
effect and the chiral separation effect is simulated in a box system with the
periodic boundary condition based on the chiral kinetic equations of motion.
Simulation results are compared with available limits from theoretical
derivations, and effects of the temperature, the magnetic field, and the
specific shear viscosity on the key properties of the chiral magnetic wave are
discussed. Our study serves as a baseline for further simulations of chiral
anomalies in relativistic heavy-ion collisions.Comment: 7 pages, 5 figure
Strange Quark Stars as Probe of Dark Matter
We demonstrate that the observation of old strange quark stars (SQSs) can set
important limits on the scattering cross sections between the light
quarks and the non-interacting scalar dark matter (DM). By analyzing a set of
1403 of solitary pulsarlike compact stars in the Milky Way, we find the old
solitary pulsar PSR J1801-0857D can set the most stringent upper limits on
or the DM-proton scattering cross sections . By converting
into based on effective operator analyses, we show the
resulting limit by assuming PSR J1801-0857D to be a SQS could be
comparable with that of the current direct detection experiments but much
weaker (by several orders of magnitude) than that obtained by assuming PSR
J1801-0857D to be a neutron star (NS), which requires an extremely small
far beyond the limits of direct detection experiments. Our findings
imply that the old pulsars are favored to be SQSs rather than NSs if the scalar
DM were observed by future terrestrial experiments.Comment: 6 pages, 4 figures. Some results updated and discussions added.
Accepted version to appear in Ap
Effects of the U-boson on the inner edge of neutron star crusts
We explore effects of the light vector -boson, which is weakly coupled to
nucleons, on the transition density and pressure at the
inner edge separating the liquid core from the solid crust of neutron stars.
Three methods, i.e., the thermodynamical approach, the curvature matrix
approach and the Vlasov equation approach are used to determine the transition
density with the Skyrme effective nucleon-nucleon interactions. We
find that the and depend on not only the ratio of coupling
strength to mass squared of the -boson but also its mass
due to the finite range interaction from the -boson exchange. In
particular, our results indicate that the and are sensitive
to both and if the -boson mass is larger than
about 2 MeV. Furthermore, we show that both and can
have significant influence on the mass-radius relation and the crustal fraction
of total moment of inertia of neutron stars. In addition, we study the exchange
term contribution of the -boson based on the density matrix expansion
method, and demonstrate that the exchange term effects on the nuclear matter
equation of state as well as the and are generally
negligible.Comment: 16 pages, 8 figures. Fig. 1 and Fig. 4 revised, typos fixed.
Published version in PR
Weak entropy solutions of nonlinear reaction-hyperbolic systems for axonal transport
This paper is concerned with a class of nonlinear reaction-hyperbolic systems
as models for axonal transport in neuroscience. We show the global existence of
entropy-satisfying BV-solutions to the initial-value problems by using
hyperbolic-type methods. Moreover, we rigorously justify the limit as the
biochemical processes are much faster than the transport ones
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