392 research outputs found
The nonrelativistic limit of the Magueijo-Smolin model of deformed special relativity
We study the nonrelativistic limit of the motion of a classical particle in a
model of deformed special relativity and of the corresponding generalized
Klein-Gordon and Dirac equations, and show that they reproduce nonrelativistic
classical and quantum mechanics, respectively, although the rest mass of a
particle no longer coincides with its inertial mass. This fact clarifies the
meaning of the different definitions of velocity of a particle available in DSR
literature. Moreover, the rest mass of particles and antiparticles differ,
breaking the CPT invariance. This effect is close to observational limits and
future experiments may give indications on its effective existence.Comment: 10 pages, plain TeX. Discussion of generalized Dirac equation and CPT
violation adde
Coulomb integrals for the SL(2,R) WZNW model
We review the Coulomb gas computation of three-point functions in the SL(2,R)
WZNW model and obtain explicit expressions for generic states. These amplitudes
have been computed in the past by this and other methods but the analytic
continuation in the number of screening charges required by the Coulomb gas
formalism had only been performed in particular cases. After showing that ghost
contributions to the correlators can be generally expressed in terms of Schur
polynomials we solve Aomoto integrals in the complex plane, a new set of
multiple integrals of Dotsenko-Fateev type. We then make use of monodromy
invariance to analytically continue the number of screening operators and prove
that this procedure gives results in complete agreement with the amplitudes
obtained from the bootstrap approach. We also compute a four-point function
involving a spectral flow operator and we verify that it leads to the one unit
spectral flow three-point function according to a prescription previously
proposed in the literature. In addition, we present an alternative method to
obtain spectral flow non-conserving n-point functions through well defined
operators and we prove that it reproduces the exact correlators for n=3.
Independence of the result on the insertion points of these operators suggests
that it is possible to violate winding number conservation modifying the
background charge.Comment: Improved presentation. New section on spectral flow violating
correlators and computation of a four-point functio
Rational Design of Novel Anticancer Small-Molecule RNA m6A Demethylase ALKBH5 Inhibitors
The RNA 6-N-methyladenosine (m6A) demethylase ALKBH5 has been shown to be oncogenic in several cancer types, including leukemia and glioblastoma. We present here the target-tailored development and first evaluation of the antiproliferative effects of new ALKBH5 inhibitors. Two compounds, 2-[(1-hydroxy-2-oxo-2-phenylethyl)sulfanyl]acetic acid (3) and 4-{[(furan-2-yl)methyl]amino}-1,2-diazinane-3,6-dione (6), with IC50 values of 0.84 mu M and 1.79 mu M, respectively, were identified in high-throughput virtual screening of the library of 144 000 preselected compounds and subsequent verification of hits in an m6A antibody-based enzyme-linked immunosorbent assay (ELISA) enzyme inhibition assay. The effect of these compounds on the proliferation of selected target cancer cell lines was then measured. In the case of three leukemia cell lines (HL-60, CCRF-CEM, and K562) the cell proliferation was suppressed at low micromolar concentrations of inhibitors, with IC50 ranging from 1.38 to 16.5 mu M. However, the effect was low or negligible in the case of another leukemia cell line, Jurkat, and the glioblastoma cell line A-172. These results demonstrate the potential of ALKBH5 inhibition as a cancer-cell-type-selective antiproliferative strategy.Peer reviewe
Local well-posedness for the space-time Monopole equation in Lorenz gauge
It is known from the work of Czubak that the space-time Monopole equation is
locally well-posed in the Coulomb gauge for small initial data in
for . Here we prove local well-posedness for
arbitrary initial data in with in the Lorenz gauge.Comment: To appear in NoDE
An aerodynamic tradeoff study of the scissor wing configuration
A scissor wing configuration, consisting of two independently sweeping wings was numerically studied. This configuration was also compared with an equivalent fixed wing baseline. Aerodynamic and stability and control characteristics of these geometries were investigated over a wide range of flight Mach numbers. It is demonstrated that in the purely subsonic flight regime, the scissor wing can achieve higher aerodynamic efficiency as the result of slightly higher aspect ratio. In the transonic regime, the lift to drag ratio of the scissor wing is shown to be higher than that of the baseline, for higer values of the lift coefficient. This tends to make the scissor wing more efficient during transonic cruise at high altitudes as well as during air combat at all altitudes. In supersonic flight, where the wings are maintained at maximum sweep angle, the scissor wing is shown to have a decided advantage in terms of reduced wave drag. From the view point of stability and control, the scissor wing is shown to have distinct advantages. It is shown that this geometry can maintain a constant static margin in supersonic as well as subsonic flight, by proper sweep scheduling. Furthermore, it is demonstrated that addition of wing mounted elevons can greatly enhance control authority in pitch and roll
The least common multiple of a sequence of products of linear polynomials
Let be the product of several linear polynomials with integer
coefficients. In this paper, we obtain the estimate: as , where is a constant depending on
.Comment: To appear in Acta Mathematica Hungaric
The Selberg trace formula for Dirac operators
We examine spectra of Dirac operators on compact hyperbolic surfaces.
Particular attention is devoted to symmetry considerations, leading to
non-trivial multiplicities of eigenvalues. The relation to spectra of
Maass-Laplace operators is also exploited. Our main result is a Selberg trace
formula for Dirac operators on hyperbolic surfaces
Some recursive formulas for Selberg-type integrals
A set of recursive relations satisfied by Selberg-type integrals involving
monomial symmetric polynomials are derived, generalizing previously known
results. These formulas provide a well-defined algorithm for computing
Selberg-Schur integrals whenever the Kostka numbers relating Schur functions
and the corresponding monomial polynomials are explicitly known. We illustrate
the usefulness of our results discussing some interesting examples.Comment: 11 pages. To appear in Jour. Phys.
Wigner quantization of some one-dimensional Hamiltonians
Recently, several papers have been dedicated to the Wigner quantization of
different Hamiltonians. In these examples, many interesting mathematical and
physical properties have been shown. Among those we have the ubiquitous
relation with Lie superalgebras and their representations. In this paper, we
study two one-dimensional Hamiltonians for which the Wigner quantization is
related with the orthosymplectic Lie superalgebra osp(1|2). One of them, the
Hamiltonian H = xp, is popular due to its connection with the Riemann zeros,
discovered by Berry and Keating on the one hand and Connes on the other. The
Hamiltonian of the free particle, H_f = p^2/2, is the second Hamiltonian we
will examine. Wigner quantization introduces an extra representation parameter
for both of these Hamiltonians. Canonical quantization is recovered by
restricting to a specific representation of the Lie superalgebra osp(1|2)
Quantum Limits of Eisenstein Series and Scattering states
We identify the quantum limits of scattering states for the modular surface.
This is obtained through the study of quantum measures of non-holomorphic
Eisenstein series away from the critical line. We provide a range of stability
for the quantum unique ergodicity theorem of Luo and Sarnak.Comment: 12 pages, Corrects a typo and its ramification from previous versio
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