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Sep 22, 2013
09/13

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Chao-Guang Huang

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From the principle of relativity with two universal invariant parameters $c$ and $l$, 24 possible kinematical (including geometrical and static) algebras can be obtained. Each algebra is of 10 dimensional, generating the symmetry of a 4 dimensional homogeneous space-time or a pure space. In addition to the ordinary Poincar\'e algebra, there is another Poincar\'e algebra among the 24 algebras. New 4d geometries with the new Poincar\'e symmetry are presented. The motion of free particles on one...

Source: http://arxiv.org/abs/1004.1268v2

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Jun 30, 2018
06/18

by
Chao-Guang Huang; Lin Li

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The contraction method in different limits to obtain 22 different realizations of kinematical algebras is applied to study the supersymmetric extension of \AdS\ algebra and its contractions. It is shown that $\frak{p}_2$ $\frak{h}_-$, $\frak{p}'$, $\frak{c}_2$ and $\frak{g}'$ algebras, in addition to $\frak{d}_-$, $\frak{p}$, $\frak{n}_-$, $\frak{g}$ and $\frak{c}$ algebras, have supersymmetric extension, while $\frak{n}_{-2}$, $\frak{g}_2$ and $\frak{g}'_2$ algebras have no supersymmetric...

Topic: High Energy Physics - Theory

Source: http://arxiv.org/abs/1409.5498

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Jun 27, 2018
06/18

by
Chao-Guang Huang; Jingbo Wang

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It is shown in this paper that the symplectic form for the system consisting of $D$-dimensional bulk Palatini gravity and SO$(1,1)$ BF theory on an isolated horizon as a boundary just contains the bulk term. An alternative quantization procedure for the boundary BF theory is presented. The area entropy is determined by the degree of freedom of the bulk spin network states which satisfy a suitable boundary condition. The gauge-fixing condition in the approach and the advantages of the approach...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1506.02805

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Jun 27, 2018
06/18

by
Jingbo Wang; Chao-Guang Huang

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In this paper, the isolated horizons with rotation are considered. It is shown that the symplectic form is the same as that in the nonrotating case. As a result, the boundary degrees of freedom can be also described by an SO$(1,1)$ BF theory. The entropy satisfies the Bekenstein-Hawking area law with the same Barbero-Immirzi parameter.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1505.03647

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Jun 30, 2018
06/18

by
Jingbo Wang; Chao-Guang Huang

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In three dimensional spacetime with negative cosmology constant, the general relativity can be written as two copies of SO$(2,1)$ Chern-Simons theory. On a manifold with boundary the Chern-Simons theory induces a conformal field theory--WZW theory on the boundary. In this paper, it is show that with suitable boundary condition for BTZ black hole, the WZW theory can reduce to a massless scalar field on the horizon.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1703.08894

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Jun 30, 2018
06/18

by
Jingbo Wang; Chao-Guang Huang

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In this paper, we extend the calculation of the entropy of the nonrotating isolated horizons in 4 dimensional spacetime to that in a higher dimensional spacetime. We show that the boundary degrees of freedom on an isolated horizon can be described effectively by a punctured $SO(1,1)$ BF theory. Then the entropy of the nonrotating isolated horizon can be calculated out by counting the microstates. It satisfies the Bekenstein-Hawking law.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1409.0985

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Jun 28, 2018
06/18

by
Jingbo Wang; Chao-Guang Huang

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In this paper, the entropy of isolated horizons in non-minimally coupling scalar field theory and in the scalar-tensor theory of gravitation is calculated by counting the degree of freedom of quantum states in loop quantum gravity. Instead of boundary Chern-Simons theory, the boundary BF theory is used. The advantages of the new approaches are that no spherical symmetry is needed, and that the final result matches exactly with the Wald entropy formula.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1507.08807

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Sep 21, 2013
09/13

by
Chao-Guang Huang; Han-Ying Guo

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A new single-dynamical-scalar-field model of dark energy is proposed, in which either higher derivative terms nor structures of extra dimension are needed. With the help of a fixed background vector field, the parameter for the effective equation of state of dark energy may cross $w=-1$ in the evolution of the universe. After suitable choice of the potential, the crossing $w=-1$ and transition from decelerating to accelerating occur at $z\approx 0.2$ and $z\approx 1.7$, respectively.

Source: http://arxiv.org/abs/astro-ph/0508171v1

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Jul 20, 2013
07/13

by
Chao-Guang Huang; Han-Ying Guo

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A new kind of uniformly accelerated reference frames with a line-element different from the M{\o}ller and Rindler ones is presented, in which every observer at $x, y, z=$consts. has the same constant acceleration. The laws of mechanics are checked in the new kind of frames. Its thermal property is studied. The comparison with the M{\o}ller and Rindler uniform accelerated reference frames is also made.

Source: http://arxiv.org/abs/gr-qc/0604008v1

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Sep 22, 2013
09/13

by
Chao-Guang Huang; Meng-Sen Ma

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It is shown that all torsion-free vacuum solutions of the model of dS gauge theory of gravity are the vacuum solutions of Einstein field equations with the same positive cosmological constant. Furthermore, for the gravitational theories with more general quadratic gravitational Lagrangian ($F^2+T^2$), the torsion-free vacuum solutions are also the vacuum solutions of Einstein field equations.

Source: http://arxiv.org/abs/0906.2622v1

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Sep 19, 2013
09/13

by
Chao-Guang Huang; Jia-Rui Sun

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We aim to study the thermodynamic properties of the spherically symmetric reference frames with uniform acceleration, including the spherically symmetric generalization of Rindler reference frame and the new kind of uniformly accelerated reference frame. We find that, unlike the general studies about the horizon thermodynamics, one cannot obtain the laws of thermodynamics for their horizons in the usual approaches, despite that one can formally define an area entropy (Bekenstein-Hawking...

Source: http://arxiv.org/abs/gr-qc/0701078v1

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Sep 21, 2013
09/13

by
Chao-Guang Huang; Yuan-Zhong Zhang

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The Poynting vector, energy density and energy velocity of light pulses propagating in anomalous dispersion medium (used in WKD-like experiments) are calculated. Results show that a negative energy density in the medium propagates along opposite of incident direction with such a velocity similar to the negative group velocity while the direction of the Poynting vector is positive. In other words, one might say that a positive energy density in the medium would propagate along the positive...

Source: http://arxiv.org/abs/physics/0104005v1

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Sep 21, 2013
09/13

by
Jia-An Lu; Chao-Guang Huang

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Weak field approximate solutions in the Lambda-->0 limit of a model of de Sitter gravity have been presented in the static and spherically symmetric case. Although the model looks different from general relativity, among those solutions, there still exist the weak Schwarzschild fields with the smooth connection to regular internal solutions obeying the Newtonian gravitational law. The existence of such solutions would determine the value of the coupling constant, which is different from that...

Source: http://arxiv.org/abs/1301.5796v1

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Sep 22, 2013
09/13

by
Chao-Guang Huang; Meng-Sen Ma

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In the model of de Sitter gauge theory of gravity, the empty homogenous and isotropic spacetimes with constant curvature scalar and nonvanishing homogenous and isotropic torsion must have de Sitter metrics. The static de Sitter spacetime with static, O(3)-symmetric, vector torsion is the only spherically symmetric, vacuum solution with the metric of the form $g_{\mu\nu}={\rm diag}(A^2(r),-B^2(r),-r^2,-r^2\sin^2\th)$. The expressions of the torsion for different de Sitter spacetimes are...

Source: http://arxiv.org/abs/0906.2837v2

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Jun 30, 2018
06/18

by
Jingbo Wang; Chao-Guang Huang; Lin Li

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In this paper, the BF theory method is applied to the nonrotating isolated horizons in Lovelock theory. The final entropy matches the Wald entropy formula for this theory. We also confirm the conclusion got by Bodendorfer et. al. that the entropy is related to the flux operator rather than the area operator in general diffeomorphic-invariant theory.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1411.0190

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Jun 29, 2018
06/18

by
Zhe Chang; Chao-Guang Huang; Zhi-Chao Zhao

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Recently, the LIGO Scientific Collaboration and Virgo Collaboration published the second observation on gravitational wave GW151226 [Phys. Rev. Lett. 116, 241103 (2016)] from the binary black hole coalescence with initial masses about 14 M$_\odot$ and 8 M$_\odot$. They claimed that the peak gravitational strain was reached at about 450 Hz, the inverse of which has been longer than the average time a photon staying in the Fabry-Perot cavities in two arms. In this case, the phase-difference of a...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1612.01615

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Sep 23, 2013
09/13

by
Xiaoning Wu; Chao-Guang Huang; Jia-Rui Sun

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Based on the idea of the work by Wilczek and his collaborators, we consider the gravitational anomaly near weekly isolated horizon. We find that there exists a universal choice of tortoise coordinate for any weakly isolated horizon. Under this coordinate, the leading behavior of a quite arbitrary scalar field near horizon is a 2-dimensional chiral scalar field. This means we can extend the idea of Wilczek and his collaborators to more general cases and show the relation between gravitational...

Source: http://arxiv.org/abs/0801.1347v1

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Jun 29, 2018
06/18

by
Zhe Chang; Chao-Guang Huang; Zhi-Chao Zhao

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The response of a detector to gravitational wave is a function of frequency. When the time a photon moving around in the Fabry-Perot cavities is the same order of the period of a gravitational wave, the phase-difference due to the gravitational wave should be an integral along the path. We present a formula description for detector response to gravitational wave with varied frequencies. The LIGO data for GW150914 and GW 151226 are reexamined in this framework. For GW150924, the traveling time...

Topics: Astrophysics, High Energy Astrophysical Phenomena, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1606.07644

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Sep 20, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Bin Zhou

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It is found that there is no period in the imaginary Beltrami-time of the de Sitter spacetime with Beltrami metric and that the `surface-gravity' in view of inertial observers in de Sitter spacetime is zero! They show that the horizon might be at zero temperature in de Sitter spacetime and that the thermal property of the horizon in the de Sitter spacetime with a static metric should be analogous to that of the Rindler horizon in Minkowski spacetime.

Source: http://arxiv.org/abs/hep-th/0404010v2

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Sep 19, 2013
09/13

by
Chao-Guang Huang; Han-Ying Guo; Xiaoning Wu

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The Noether-charge realization and the Hamiltonian realization for the $\diff({\cal M})$ algebra in diffeomorphism invariant gravitational theories are studied in a covariant formalism. For the Killing vector fields, the Nother-charge realization leads to the mass formula as an entire vanishing Noether charge for the vacuum black hole spacetimes in general relativity and the corresponding first law of the black hole mechanics. It is analyzed in which sense the Hamiltonian functionals form the...

Source: http://arxiv.org/abs/gr-qc/0304037v1

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Jun 29, 2018
06/18

by
Zhe Chang; Chao-Guang Huang; Zhi-Chao Zhao

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The photon motion in a Michelson interferometer is re-analyzed in both geometrical optics and wave optics. The classical paths of the photons in the background of gravitational wave are derived from Fermat principle, which is the same as the null geodesics in general relativity. The deformed Maxwell equations and the wave equations of electric fields in the background of gravitational wave are presented in flat-space approximation. Both methods show that the response of an interferometer...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1612.06939

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77

Sep 19, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Xiaoning Wu

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It is shown in the covariant phase space formalism that the Noether charges with respect to the diffeomorphism generated by vector fields and their horizontal variations in general relativity form a diffeomorphism algebra. It is also shown with the help of the null tetrad which is well defined everywhere that the central term of the reduced diffeomorphism algebra on the Killing horizon for a large class of vector fields vanishes.

Source: http://arxiv.org/abs/gr-qc/0208067v1

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Sep 23, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Hong-Tu Wu

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We show that if Yang's model as the earliest TSR is completed, it should contain both Snyder's quantized space-time model as the earliest DSR, the de Sitter SR and their duality.

Source: http://arxiv.org/abs/0801.1146v2

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Sep 18, 2013
09/13

by
Hong-Tu Wu; Chao-Guang Huang; Han-Ying Guo

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By means of Dirac procedure, we re-examine Yang's quantized space-time model, its relation to Snyder's model, the de Sitter special relativity and their UV-IR duality. Starting from a dimensionless dS_5-space in a 5+1-d Mink-space a complete Yang model at both classical and quantum level can be presented and there really exist Snyder's model, the dS special relativity and the duality.

Source: http://arxiv.org/abs/0809.3560v1

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Sep 23, 2013
09/13

by
Chao-Guang Huang; Hai-Qing Zhang; Han-Ying Guo

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The torsion is shown to be vitally important in the explanation of the evolution of the universe in a large class of gravitational theories containing quadratic terms of curvature and torsion. The cosmological solutions with homogeneous and isotropic torsion in a model of de Sitter gauge theory of gravity are presented, which may explain the observation data for SN Ia when parameters are suitably chosen and supply a natural transit from decelerating expansion to accelerating expansion without...

Source: http://arxiv.org/abs/0801.0905v1

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Jul 20, 2013
07/13

by
Zhe Chang; Cheng-Bo Guan; Chao-Guang Huang; Xin Li

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We investigate the gravitational collapse of a spherically symmetric, inhomogeneous star, which is described by a perfect fluid with heat flow and satisfies the equation of state $p=\rho/3$ or $p=C\rho^\ga$ at its center. Different from the ordinary process of gravitational collapsing, the energy of the whole star is emitted into space. And the remaining spacetime is a Minkowski one at the end of the process.

Source: http://arxiv.org/abs/0804.3892v1

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Sep 21, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Zhan Xu; Bin Zhou

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Since the special relativity can be viewed as the physics in an inverse Wick rotation of 4-d Euclid space, which is at almost equal footing with the 4-d Riemann/Lobachevski space, there should be important physics in the inverse Wick rotation of 4-d Riemann/Lobachevski space. Thus, there are three kinds of special relativity in de Sitter/Minkowski/anti-de Sitter space at almost equal footing, respectively. There is an instanton tunnelling scenario in the Riemann-de Sitter case that may explain...

Source: http://arxiv.org/abs/hep-th/0508094v1

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Sep 21, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Zhan Xu; Bin Zhou

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Based on some important properties of $dS$ space, we present a Beltrami model ${\cal B}_\Lambda$ that may shed light on the observable puzzle of $dS$ space and the paradox between the special relativity principle and cosmological principle. In ${\cal B}_\Lambda$, there are inertial-type coordinates and inertial-type observers. Thus, the classical observables can be defined for test particles and light signals. In addition, by choosing the definition of simultaneity the Beltrami metric is...

Source: http://arxiv.org/abs/hep-th/0311156v1

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Sep 22, 2013
09/13

by
Xiaoning Wu; Han-Ying Guo; Chao-Guang Huang; Ke Wu

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The Noether current and its variation relation with respect to diffeomorphism invariance of gravitational theories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian, respectively. For Einstein's GR in the stationary, axisymmetric black holes, the mass formula in vacuum can be derived from this Noether current although it definitely vanishes. This indicates that the mass formula of black holes is a vanishing Noether charge in this case. The...

Source: http://arxiv.org/abs/gr-qc/0201100v1

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Sep 22, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Zhan Xu; Bin Zhou

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Based on the principle of relativity and the postulate of invariant speed and length, we propose the theory of special relativity with cosmological constant ${\cal SR}_{c,R}$ if the invariant length whose square is the inverse of the one-third cosmological constant of the universe. It is on the Beltrami-de Sitter spacetime ${\cal B}_R$ with de Sitter invariance. We define the observables of free particles and generalize famous Einstein's formula. We also define two kinds of simultaneity. The...

Source: http://arxiv.org/abs/hep-th/0403171v1

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Sep 18, 2013
09/13

by
Zhe Chang; Cheng-Bo Guan; Chao-Guang Huang; Xin Li

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We investigate the gravitational collapse of a spherically symmetric, inhomogeneous star, which is described by a perfect fluid with heat flow and satisfies the equation of state $p=\rho/3$ at its center. In the process of the gravitational collapsing, the energy of the whole star is emitted into space. And the remaining spacetime is a Minkowski one without a remnant at the end of the process. For a star with a solar mass and solar radius, the total energy emitted is at the order of $10^{54}$...

Source: http://arxiv.org/abs/0803.3661v1

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Jul 20, 2013
07/13

by
Chao-Guang Huang; Yu Tian; Xiaoning Wu; Han-Ying Guo

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It is shown that all vacuum solutions of Einstein field equation with a positive cosmological constant are the solutions of a model of dS gauge theory of gravity. Therefore, the model is expected to pass the observational tests on the scale of solar system and explain the indirect evidence of gravitational wave from the binary pulsars PSR1913+16.

Source: http://arxiv.org/abs/0804.4339v1

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Sep 23, 2013
09/13

by
Chao-Guang Huang; Jia-Rui Sun; Xiaoning Wu; Hai-Qing Zhang

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We apply Wilczek and his collaborators' anomaly cancellation approach to the 3-dimensional Schwarzschild- and BTZ-like brane world black holes induced by the generalized C metrics in the Randall-Sundrum scenario. Based on the fact that the horizon of brane world black hole will extend into the bulk spacetime, we do the calculation from the bulk generalized C metrics side and show that this approach also reproduces the correct Hawking radiation for these brane world black holes. Besides, since...

Source: http://arxiv.org/abs/0710.4766v2

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Sep 18, 2013
09/13

by
Zhe Chang; Shao-Xia Chen; Cheng-Bo Guan; Chao-Guang Huang

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We discuss the threshold anomaly in ultra-high energy cosmic ray physics by assuming that the matter world just be perturbation of a de Sitter universe, which is consistent with the recent astronomical observations: about two thirds of the whole energy in the universe is contributed by a small positive cosmological constant. One-particle states are presented explicitly. It is noticed that the dispersion relation of free particles is dependent on the degrees of freedom of angular momentum. This...

Source: http://arxiv.org/abs/astro-ph/0505612v1

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Sep 22, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Hong-Tu Wu; Bin Zhou

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Based on the principle of relativity and the postulate on universal invariant constants (c,l), all possible kinematics can be set up with sub-symmetries of the Umov-Weyl-Fock transformations for the inertial motions. Further, in the combinatory approach, all these symmetries are intrinsically related to each other, e.g. to the very important dS kinematics for the cosmic scale physics.

Source: http://arxiv.org/abs/0812.0871v2

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Jul 20, 2013
07/13

by
Chao-Guang Huang; Yu Tian; Xiao-Ning Wu; Zhan Xu; Bin Zhou

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The algebras for all possible Lorentzian and Euclidean kinematics with $\frak{so}(3)$ isotropy except static ones are re-classified. The geometries for algebras are presented by contraction approach. The relations among the geometries are revealed. Almost all geometries fall into pairs. There exists $t \leftrightarrow 1/(\nu^2t)$ correspondence in each pair. In the viewpoint of differential geometry, there are only 9 geometries, which have right signature and geometrical spatial isotropy. They...

Source: http://arxiv.org/abs/1007.3618v1

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Sep 22, 2013
09/13

by
Chao-Guang Huang; Han-Ying Guo; Yu Tian; Zhan Xu; Bin Zhou

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Based on the Beltrami-de Sitter spacetime, we present the Newton-Hooke model under the Newton-Hooke contraction of the $BdS$ spacetime with respect to the transformation group, algebra and geometry. It is shown that in Newton-Hooke space-time, there are inertial-type coordinate systems and inertial-type observers, which move along straight lines with uniform velocity. And they are invariant under the Newton-Hooke group. In order to determine uniquely the Newton-Hooke limit, we propose the...

Source: http://arxiv.org/abs/hep-th/0403013v3

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Sep 20, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Yu Tian; Zhan Xu; Bin Zhou

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Weakening the Euclidean assumption in special relativity and the coordinate-independence hypothesis in general relativity for the de Sitter space, we propose a de Sitter invariant special relativity with two universal constants of speed $c$ and length $R$ based on the principle of relativity and the postulate of universal constants $c$ and $R$ on de Sitter space with Beltrami metric. We also propose a postulate on the origin of the inertial motions and inertial systems as a base of the...

Source: http://arxiv.org/abs/hep-th/0405137v3

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Sep 20, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Yu Tian; Zhan Xu; Bin Zhou

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There is a one-to-one correspondence between Snyder's model in de Sitter space of momenta and the \dS-invariant special relativity. This indicates that physics at the Planck length $\ell_P$ and the scale $R=3/\Lambda$ should be dual to each other and there is in-between gravity of local \dS-invariance characterized by a dimensionless coupling constant $g=\ell_P/R\sim 10^{-61}$.

Source: http://arxiv.org/abs/hep-th/0607016v2

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Sep 19, 2013
09/13

by
Chao-Guang Huang; Yu Tian; Xiao-Ning Wu; Zhan Xu; Bin Zhou

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The new 4D geometry whose Killing vectors span the Poincar\'e algebra is presented and its structure is analyzed. The new geometry can be regarded as the Poincar\'e-invariant solution of the degenerate extension of the vacuum Einstein field equations with a negative cosmological constant and provides a static cosmological space-time with a Lobachevsky space. The motion of free particles in the space-time is discussed.

Source: http://arxiv.org/abs/0909.2773v2

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Sep 23, 2013
09/13

by
Yu Tian; Han-Ying Guo; Chao-Guang Huang; Zhan Xu; Bin Zhou

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We focus on the dynamical aspects of Newton-Hooke space-time ${\cal NH}_+$ mainly from the viewpoint of geometric contraction of the de Sitter spacetime. We first discuss the Newton-Hooke classical mechanics, especially the continuous medium mechanics, in this framework. Then, we establish a consistent theory of gravity on the Newton-Hooke space-time as a kind of Newton-Cartan-like theory, parallel to the Newton's gravity in the Galilei space-time. Finally, we give the Newton-Hooke invariant...

Source: http://arxiv.org/abs/hep-th/0411004v2

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Sep 21, 2013
09/13

by
Chao-Guang Huang; Yu Tian; Xiao-Ning Wu; Zhan Xu; Bin Zhou

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The second Poincar\'e kinematical group serves as one of new ones in addition to the known possible kinematics. The geometries with the second Poincar\'e symmetry is presented and their properties are analyzed. On the geometries, the new mechanics based on the principle of relativity with two universal constants $(c,l)$ can be established.

Source: http://arxiv.org/abs/1204.4290v1

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Sep 19, 2013
09/13

by
Han-Ying Guo; Chao-Guang Huang; Yu Tian; Hong-Tu Wu; Zhan Xu; Bin Zhou

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Between Snyder's quantized space-time model in de Sitter space of momenta and the \dS special relativity on \dS-spacetime of radius $R$ with Beltrami coordinates, there is a one-to-one dual correspondence supported by a minimum uncertainty-like argument. Together with Planck length $\ell_P$, $R\simeq (3/\Lambda)^{1/2}$ should be a fundamental constant. They lead to a dimensionless constant $g{\sim\ell_PR^{-1}}=(G\hbar c^{-3}\Lambda/3)^{1/2}\sim 10^{-61}$. These indicate that physics at these...

Source: http://arxiv.org/abs/gr-qc/0703078v2