arXiv subjects

Yong-Chang Huang

Publications and source records attributed to Yong-Chang Huang.

At least 37 records · Page 2Linked to original sources

arXiv2016

Some New Symmetric Relations and the Prediction of Left and Right Handed Neutrino Masses using Koide's Relation

Masses of the three generations of charged leptons are known to completely satisfy the Koide's mass relation. But the question remains if such a relation exists for neutrinos? In this paper, by considering SeeSaw mechanism as the mechanism generating tiny neutrino masses, we show how neutrinos satisfy the Koide's mass relation, on the basis of which we systematically give exact values of not only left but also right handed neutrino masses.

hep-ph↗

arXiv2016

Tackling tangledness of cosmic strings by knot polynomial topological invariants

Cosmic strings in the early universe have received revived interest in recent years. In this paper we derive these structures as topological defects from singular distributions of the quintessence field of dark energy. Our emphasis is placed on the topological charge of tangled cosmic strings, which originates from the Hopf mapping and is a Chern-Simons action possessing strong inherent tie to knot topology. It is shown that the Kauffman bracket knot polynomial can be constructed in terms of this charge for un-oriented knotted strings, serving as a topological invariant much stronger than the traditional Gauss linking numbers in characterizing string topology. Especially, we introduce a mathematical approach of breaking-reconnection which provides a promising candidate for studying physical reconnection processes within the complexity-reducing cascades of tangled cosmic strings.

hep-th↗

arXiv2016

Counting similarities between tetraquark and mesonic/gluonic operators

After the study of the preclusion of exotic meson states in large-$N_c$ limit QCD, combining Weinberg's opposite proposal, we get different counting orders for a tetraquark operator to create or destroy an one-tetraquark state. Meanwhile, by comparing tetraquark operator with the mesonic and gluonic operators, we find that tetraquark operators are similar with mesonic and gluonic operators in the counting. Furthermore, we find a mixing of different kinds of operators.

hep-ph↗

arXiv2015

The cosmology in f(R,T) gravity without dark energy

We examine the evolution of universe in $f(R,T)$ gravity where $R$ is the Ricci curvature and $T$ is the trace of energy momentum tensor. We focus on the specific form $f(R,T) = R+f(T)$ and explicitly find out the relation between $f(T)$ and state of equation $w$ by adiabatic condition. All possible modes of evolution of the scale factor for the five kinds of state of equation, $w= \pm 1, \pm 1/3, 0$ are exhibited. We simulate numerically the plots of redshift versus distance modulus for three interesting modes and then obtain the good fitting curve compared with the astronomical observation data.

gr-qc↗

arXiv2015

Entropy spectrum of the apparent horizon of Vaidya black holes via adiabatic invariance

The spectroscopy of the apparent horizon of Vaidya black holes is investigated via adiabatic invariance. We obtain an equally spaced entropy spectrum with its quantum equal to the one given by Bekenstein. We demonstrate that the quantization of entropy and area is a generic property of horizon, not only for stationary black holes, and the results also exit in a dynamical black hole. Our work also shows that the quantization of black hole is closely related to Hawking temperature, which is an interesting thing.

gr-qc↗

arXiv2015

Kerr Black string flow

We give a general theory of a rotated black string stream into a rotational horizon in dimension D=5. It is a configuration about one smooth intersection between these two objects when the spacetime is axisymmetric and in the limit that the thickness of the black hole is much larger than the thickness of the black string. Following this configuration we extend to a more general situation, the rotational charged flows.

hep-th↗

arXiv2015

Symmetry of Generalized Randall-Sundrum Model and Distribution of 3-Branes in Six-Dimensional Spacetime

A generalization from the usual $5$-dimensional two-brane Randall-Sundrum (RS) model to a $6$-dimensional multi-brane RS model is presented. The extra dimensions are extended from one to two; correspondingly the single-variable warp function is generalized to be a double-variable function, to represent the two extra dimensions. In the analysis of the Einstein equation we have two remarkable discoveries. One is that, when branes are absent, the cosmological parameter distributed in the two extra dimensions acts as a function describing a family of circles. These circles are not artificially added ones but stem from the equations of motion, while their radii are inversely proportional to the square root of the cosmological parameter. The other discovery is that, on any circle, there symmetrically distribute four branes. Their tensions, $V_1 \sim V_4$, satisfy a particular relationship $V_1=V_3=-V_2=-V_4=3M^4$, where $M$ is the $6$-dimensional fundamental scale of the RS model.

gr-qc↗

arXiv2015

Thermodynamic fluctuation in black string flow

It has long been noticed that Laudau-Lifshitz theory can be used to study the fluctuation of a system that contains a black hole. Since the black string can be constructed by extending n-dimensional black hole into one extra dimension. We study the fluctuation of black string flow with a Schwarzschlid-like metric in D=n+1 dimensional spacetime and a charged solution in D=5 dimensional spacetime and get the second moments of the fluctuation of the mass flux and charge flux.

gr-qc↗

arXiv2015

Spectroscopy of a weakly isolated horizon

The spectroscopy of a weakly isolated horizon (WIH) has been investigated. We obtain an equally spaced entropy spectrum with its quantum equal to the one given by Bekenstein [5]. We demonstrate that the quantization of entropy and area is a generic property of horizon, and the results exit in a wide class of spacetimes admitting weakly isolated horizons. Our results also indicate that the entropy quantum of the black hole horizon is closely related to Hawking temperature.

gr-qc↗

arXiv2015

Variable Extra Dimensional Spacetime and Solution to Initial Singularity Paradox of Our Universe From Extra Dimensions

Considering a n-dimensional general spacetime, we deduce its 4-dimensional Einstein equation and Friedman equations, and discover a general dual relation between the scale factor $a(t)$ of our universe and the scale factor $B(t)$ of extra dimensions. Based on the dual relation equation, predictions of shrinking of extra dimensions and free of singularity problem of our universe are given. Therefore, solution to initial singularity paradox of our universe is achieved. Because the dual relation is general, this Letter discovers that it is just the extra dimensional shrinking contribution that results in our universe's expanding in terms of the dual relation in the bulk space, and actually the dual relation is deduced doesn't depend on the 4-dimensional matter concrete Lagrangian, these are key important for a lot of future relative investigations.

gr-qc↗

arXiv2015

Revisiting the tunneling spectrum and information recovery of a general charged and rotating black hole

In this paper we revisit the tunneling spectrum of a charged and rotating black hole--Kerr-Newman black hole by using Parikh and Wilczek's tunneling method and get the most general result compared with the works [9, 10]. We find an ambiguity in Parikh and Wilczek's tunneling method, and give a reasonable description. We use this general spectrum to discuss the information recovery based on the Refs. [11-13]. For the tunneling spectrum we obtained, there exit correlations between sequential Hawking radiations, information can be carried out by such correlations, and the entropy is conserved during the radiation process. So we resolve the information loss paradox based on the methods [11-13] in the most general case.

gr-qc↗

arXiv2014

Vector particles tunneling from BTZ black holes

In this paper we investigate vector particles' Hawking radiation from a BTZ black hole. By applying the WKB approximation and the Hamilton-Jacobi Ansatz to the Proca equation, we obtain the tunneling spectrum of vector particles. The expected Hawking temperature is recovered.

gr-qc↗

arXiv2014

Recovering information of tunneling spectrum from Weakly Isolated Horizon

In this paper we investigate the properties of tunneling spectrum from weakly isolated horizon(WIH). We find that there are correlations among Hawking radiations from weakly isolated horizon, the information can be carried out in terms of correlations between sequential emissions, and the radiation is an entropy conservation process. We generalize Refs.[11-13]' results to a more general spacetime. Through revisiting the calculation of tunneling spectrum of weakly isolated horizon, we find that Ref.[12]'s requirement that radiating particles have the same angular momenta of unit mass as that of black hole is not needed, and the energy and angular momenta of emitting particles are very arbitrary which should be restricted only by keeping the cosmic censorship of black hole.

gr-qc↗

arXiv2014

Gas Model of Gravitons with Light Speed

We first review some aspects of gravitational wave and the thermodynamic expression of Einstein field equations, these achieved conclusions allow people to think of Einstein's gravitational wave as a kind of sound wave in ordinary gas which propagates as an adiabatic compression wave. In the following, using the properties of photon gas in "white wall box", we find an analogous relationship between ordinary gas and photon gas through sound velocity formula. At last, by taking the ordinary gas as an intermediary, we find that gravitational wave is analogous to photon gas, or equally, gravitons are analogous to photons although they are different in some ways such as spins and coupling strengths, and these different properties don't affect their propagation speeds. Utilizing this analogous relationship, we achieve the gas model of gravitons and this model naturally gives out the light speed of gravitons

gr-qc↗

arXiv2014

Extra Dimensions, Dual Relation and the Cosmological Constant

We consider a general n dimensional manifold, which is a direct product manifold of $M^4 \times M^{n-4}$ representing our universe and extra spatial dimensions. From Einstein-Hilbert action of the manifold, we deduce effective 4 dimensional Fridemann equations. Matching it with the normal Fridemann equations with the cosmological constant, we give an expression of the cosmological constant, and the expression under different conditions are discussed. Also according to a deduced relation, we reveal a connection between Hubble parameter and extra dimensions. In this regard, we take into account all possible states of extra dimension which are consistent with current experimental result as well.

gr-qc↗

arXiv2013

$f(T)$ gravity from holographic Ricci dark energy model with new boundary conditions

Commonly used boundary conditions in reconstructing $f(T)$ gravity from holographic Ricci dark energy model (RDE) are found to cause some problem, we therefore propose new boundary conditions in this paper. By reconstructing $f(T)$ gravity from the RDE with these new boundary conditions, we show that the new ones are better than the present commonly used ones since they can give the physically expected information, which is lost when the commonly used ones are taken in the reconstruction, of the resulting $f(T)$ theory. Thus, the new boundary conditions proposed here are more suitable for the reconstruction of $f(T)$ gravity.

gr-qc↗

arXiv2013

Quantum Radiation Properties of Dirac Particles in General Nonstationary Black Holes

Quantum radiation properties of Dirac particles in general nonstationary black holes in the general case is investigated by both using the method of generalized tortoise coordinate transformation and considering the asymptotic behaviors of both the first and second order forms of Dirac equations near the event horizon. It is generally shown that the temperature and shape of event horizon of this kind of black holes depend on both the time and different angles. Further, we give a general expression of the new extra coupling effect in thermal radiation spectrum of Dirac particles which is missing in that of scalar particles. Also, we reveal a relationship that is ignored before between thermal radiation and non-thermal radiation in the case of scalar particles, which is that the chemical potential in thermal radiation spectrum is equal to the highest energy of the negative energy state of scalar particles in non-thermal radiation for general nonstationary black holes.

gr-qc↗

arXiv2013

Entropic corrections and modified Friedmann equations in the emergence of cosmic space

In the emergent cosmic space scenario recently proposed by Padmanabhan, the expansion of the universe is attributed to the difference between the number of degrees of freedom on a holographic surface and the one in the bulk. Based on this idea, we explore the cases where logarithmic and power-law entropic corrections are present, respectively. The previously found modified Friedmann equations are reproduced through an improved proposal, and we show that the same results can be obtained using a generalized expansion law.

gr-qc↗