119177731
Spectroscopy of the Einstein–Maxwell–Dilaton–Axion black hole
The entropy spectrum of a spherically symmetric black hole was derived via the Bohr–Sommerfeld quantization rule in Majhi and Vagenas’s work. Extending this work to charged and rotating black holes, we quantize the horizon area and the entropy of an Einstein–Maxwell–Dilaton–Axion black hole via the Bohr–Sommerfeld quantization rule and the adiabatic invariance. The result shows the area spectrum and the entropy spectrum are respectively equally spaced and independent on the parameters of the black hole.
55495910
Homogeneous Field and WKB Approximation in Deformed Quantum Mechanics with Minimal Length
In the framework of the deformed quantum mechanics with a minimal length, we consider the motion of a nonrelativistic particle in a homogeneous external field. We find the integral representation for the physically acceptable wave function in the position representation. Using the method of steepest descent, we obtain the asymptotic expansions of the wave function at large positive and negative arguments. We then employ the leading asymptotic expressions to derive the WKB connection formula, which proceeds from classically forbidden region to classically allowed one through a turning point. By the WKB connection formula, we prove the Bohr-Sommerfeld quantization rule up to . We also show that if the slope of the potential at a turning point is too steep, the WKB connection formula is no longer valid around the turning point. The effects of the minimal length on the classical motions are investigated using the Hamilton-Jacobi method. We also use the Bohr-Sommerfeld quantization to study statistical physics in deformed spaces with the minimal length.
55601550
Fermion's Tunnelling with Effects of Quantum Gravity
In this paper, using Hamilton-Jacobi method, we address the tunnelling of fermions in a 4-dimensional Schwarzschild spacetime. Based on the generalized uncertainty principle, we introduce 
the influence of quantum gravity. After solving the equation of motion of the spin-1/2 field, we 
derive the corrected Hawking temperature. It turns out that the correction depends not only on 
the black hole’s mass but also on the mass (energy) of emitted fermions. It is of interest that, in 
our calculation, the quantum gravity correction decelerates the temperature increase during the radiation 
explicitly. This observation then naturally leads to the remnants in black hole evaporation. 
Our calculation shows that the residue mass is , where is the Planck mass and is a dimensionless parameter accounting for quantum gravity effects. The evaporation singularity is 
then avoided.
1154617
Stress Tensors in p-adic String Theory and Truncated OSFT
We construct the stress tensors for the p-adic string model and for the pure tachyonic sector of open string field theory by naive metric covariantization of the action. Then we give the concrete energy density of a lump solution of the p-adic model. In the cubic open bosonic string field theory, we also give the energy density of a lump solution and pressure evolution of a rolling tachyon solution.
13902096
Dilaton deformations in closed string field theory
The dilaton theorem implies that the contribution to the dilaton potential from cubic interactions of all levels must be cancelled by the elementary quartic self-coupling of dilatons. We use this expectation to test the quartic structure of closed string field theory and to study the rules for level expansion. We explain how to use the results of Moeller to compute quartic interactions of states that, just like the dilaton, are neither primary nor have a simple ghost dependence. Our analysis of cancellations is made richer by discussing simultaneous dilaton and marginal deformations. We find evidence for two facts: as the level is increased quartic interactions become suppressed and closed string field theory may be able to describe arbitrarily large dilaton deformations.
118539816
Superluminal Neutrinos and Monopoles
In this letter, we show that superluminal neutrinos announced by OPERA could be explained by the existence of a monopole, which is left behind after the spontaneous symmetry breaking (SSB) phase transition of some scalar fields in the universe. We assume the 't Hooft-Polyakov monopole couples to the neutrinos but not photon fields. The monopole introduces a different effective metric to the neutrinos from the one experienced by photons. We find that the superluminal propagation only exists in a very short distance from the monopole, about $10^3$ cm in OPERA. No matter how far they travel, neutrinos always arrive earlier than photons by the same amount of time, provided a monopole existing on or close to their trajectories. This conclusion can be tested by future experiments. The result reconciles the contradiction between OPERA and supernova neutrinos. We further exclude cosmic strings as a possible theoretical explanation.
14942523
Studies of stability and robustness for artificial neural networks and boosted decision trees
In this paper, we compare the performance, stability and robustness of Artificial Neural Networks (ANN) and Boosted Decision Trees (BDT) using MiniBooNE Monte Carlo samples. These methods attempt to classify events given a number of identification variables. The BDT algorithm has been discussed by us in previous publications. Testing is done in this paper by smearing and shifting the input variables of testing samples. Based on these studies, BDT has better particle identification performance than ANN. The degradation of the classifications obtained by shifting or smearing variables of testing results is smaller for BDT than for ANN.
119092503
Anyonic physical observables and spin phase transition
The quantization of charged matter system coupled to Chern-Simons gauge fields is analyzed in a covariant gauge fixing, and gauge invariant physical anyon operators satisfying fractional statistics are constructed in a symmetric phase, based on Dirac's recipe performed on QED. This method provides us a definite way of identifying physical spectrums free from gauge ambiguity and constructing physical anyon operators under a covariant gauge fixing. We then analyze the statistical spin phase transition in a symmetry-broken phase and show that the Higgs mechanism transmutes an anyon satisfying fractional statistics into a canonical boson, a spin 0 Higgs boson or a topologically massive photon.
14202450
On the point - like structure for super p-branes
We present an efficient method to understand the p-brane dynamics in a unified framework. For this purpose, we reformulate the action for super p-branes in the form appropriate to incorporate the pointlike (parton) structure of higher dimensional p-branes and intend to interpret the p-brane dynamics as the collective dynamics of superparticles. In order to examine such a parton picture of super p-branes, we consider various superparticle configurations that can be reduced from super p-branes, especially, a supermembrane, and study the partonic structure of classical p-brane solutions.
15148506
Baryon Spectroscopy at Beijing Electron Positron Collider
Baryons are the basic building blocks of our world. If we cut any piece of object smaller and smaller,we will ﬁnally reach the nucleons, i.e., the lightest baryons, and we cannot cut them smaller anyfurther. So without mention any theory, we know that the study of baryon structure is at theforefront of exploring microscopic structure of matter. From theoretical point of view, since baryonsrepresent the simplest system in which the three colors of QCD neutralize into colorless objectsand the essential non-Abelian character of QCD is manifest, understanding the baryon structure isabsolutely necessary before we claim that we really understand QCD.Spectroscopy has long proved to be a powerful tool for exploring internal structures and basicinteractions of microscopic world. Ninety years ago detailed studies of atomic spectroscopy resultedin the great discovery of Niels Bohr’s atomic quantum theory [1]. Forty to sixty years later, stilldetailed studies of nuclear spectroscopy resulted in Nobel Prize winning discoveries of nuclear shellmodel [2] and collective motion model [3] by Aage Bohr et al. Comparing with the atomic andnuclear spectroscopy at those times, our present baryon spectroscopy is still in its infancy [4].Many fundamental issues in baryon spectroscopy are still not well understood [5]. The possibilityof new, as yet unappreciated, symmetries could be addressed with accumulation of more data.The new symmetries may not have obvious relation with QCD, just like nuclear shell model andcollective motion model.Joining the new eﬀort on studying the excited nucleons, N
11205361
The CP(n) model on noncommutative plane
We construct the consistent CP(n) model on noncommutative plane. The Bogomolny bound on the energy is saturated by (anti-)self-dual solitons with integer topological charge, which is independent of their scaling and orientation. This integer quantization is satisfied for our general solutions, which turns out regular everywhere. We discuss the possible implication of our result to the instanton physics in Yang–Mills theories on noncommutative R4.