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1.
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 entropy). In fact, the common horizon for a set of uniformly accelerated observers does not always exist, even though the Hawking-Unruh temperature is still well-defined. This result indicates that the Hawking-Unruh temperature is only a kinematic effect, and to gain the laws of thermodynamics for the horizon, one needs the help of dynamics. Our result is in accordance with those from the various studies about the acoustic black holes.  相似文献   

2.
We give a study on the general Møller transformation and emphatically introduce its differential form. In this paper, a definition of acceleration is given in spacetime language and the inertial reference frame is also settled. With a discussion of thegeodesic equations of motion, the differential form of the general Møller transformation at arbitrary direction is presented.  相似文献   

3.
Recently, corrections to the standard Einstein-Hilbert action were proposed to explain the current cosmic acceleration in stead of introducing dark energy. In the Palatini formulation of those modified gravity models, there is an important observation due to Arkani-Hamed: matter loops will give rise to a correction to the modified gravity action proportional to the Ricci scalar of the metric. In the presence of such a term, we show that the current forms of modified gravity models in Palatini formulation, specifically, the 1/ R gravity and In R gravity, will have phantoms. Then we study the possible instabilities due to the presence of phantom fields. We show that the strong instability in the metric formulation of 1/R gravity indicated by Dolgov and Kawasaki will not appear and the decay timescales for the phantom fields may be long enough for the theories to make sense as effective field theory. On the other hand, if we change the sign of the modification terms to eliminate the phantoms, some other inconsistencies will arise for the various versions of the modified gravity models. Finally, we comment on the universal property of the Palatini formulation of the matter loops corrected modified gravity models and its implications.  相似文献   

4.
I discuss the modification of Einstein's Theory of General Relativity based on a periodic functional approach. In this new approach, a corrected periodic gravitational coupling constant arises and plays the role of periodic damping term acting on the theory. It is found that it is achievable to have an oscillating universe dominated by dark energy and expanding aceeleratedly in time.  相似文献   

5.
6.
The field equations of general relativity are solved to post-Newtonian order for a frame of reference having an arbitrary time-dependent, translational acceleration and an arbitrary time-dependent angular velocity. The derivation is based on a new 3+1 decomposition of the Einstein field equations and geodesic equation of motion. The resulting space-time metric and equation of motion contain gravitational terms, inertial terms, and coupled gravitational-inertial terms. These effects are expressed explicitly in terms of the Newtonian potential and standard post-Newtonian scalar and vector potentials. The physical meaning of the formulas derived is illustrated by application to a system of point-like gravitating masses. These results should be useful for the investigation of general relativistic effects in the analysis of real experimental measurements made with respect to a noninertial frame of reference, such as the surface of the rotating earth or an accelerated spacecraft.  相似文献   

7.
8.
By considering the fluctuation of grand potential f~ around equilibrium with respect to small one-particle density fluctuations δpα(r→), the phase instability of restricted primitive model (RPM) of ionic systems is investigated. We use the integral equation theory to calculate the direct correlation functions in the reference hypernetted chain approximation and obtain the spinodai line of RPM. Our anaiysis explicitly indicates that the gas-fluid phase instability is induced by k = 0 fluctuation mode, while the fluid-solid phase instability is related to k ≠ 0 fluctuation modes. The spinodai line is qualitatively consistent with the result of computer simulations by others.  相似文献   

9.
Grounds and applications of Bargmann-Michel-Telegdi equations for the precession of the polarization vector of relativistic particles are considered. A critical question in the discussion is the orientation of the rest frame reference vectors. Møller reference frames which keep constant the mutual orientation of the two infinitely close in time rest frames are shown to have a special role. The generally covariant form of the equations is discussed. The assertion that the principle of relativity is violated in the phenomenon of spin precession is proved to be untrue.  相似文献   

10.
11.
Potential energy curves (PECs) for the ground state (X2∑+) and the four excited electronic states (A2∏, B2∏, C2∑+, 4∏) of a Bell molecule are calculated using the multi-configuration reference single and double excited configuration interaction (MRCI) approach in combination with the aug-cc-pVTZ basis sets. The calculation covers the internuclear distance ranging from 0.07 nm to 0.70 nm, and the equilibrium bond length Re and the vertical excited energy Te are determined directly. It is evident that the X2∑+, A2∏, B2∏, C2∑+ states are bound and 4∏ is a repulsive excited state. With the potentials, all of the vibrational levels and inertial rotation constants are predicted when the rotational quantum number J is set to be equal to zero (J = 0) by numerically solving the radial SchrSdinger equation of nuclear motion. Then the spectroscopic data are obtained including the rotation coupling constant w e, the anharmonic constant WeXe, the equilibrium rotation constant Be, and the vibration-rotation coupling constant ae. These values are compared with the theoretical and experimental results currently available, showing that they are in agreement with each other.  相似文献   

12.
Huey-Wen Lin 《中国物理 C》2009,33(12):1238-1243
In this proceeding, I review the attempts to calculate the Nucleon resonance (including Roper as first radially excited state of nucleon and other excited states) using lattice quantum chromodynamics (QCD). The latest preliminary results from Hadron Spectrum Collaboration (HSC) with mπ≈ 380 MeV are reported. The Sachs electric form factor of the proton and neutron and their transition with the Roper at large Q2 are also updated in this work.  相似文献   

13.
After presenting the infinite operator-sum form solution to the Milburnequation d ρ/dt=γ (Uρ U+-ρ ) =γU[ρ,U+], where U=exp(-i H/\hbar{γ}), and verifying that this equation preserves the three necessary conditions of density operators during time evolution, we prove that the von Neumann entropy increases with time. We also point out that if A and B both obey the Milburn equation, then the product AB obeys (d/dt)( AB) =γ U[ AB,U+] -(1/γ) (dA/dt)(dB/dt), which violates the Milburn equation, this reflects that a pure state will evolve to a mixture in general.  相似文献   

14.
In this paper, we intend to clarify the energy-momentum problem of higher dimensional Vaidya space-time in the general theory of relativity. In this connection, Møller energy and momentum for the higher dimensional Vaidya space-time are evaluated in the frame of general relativity. We have obtained that the Møller energy distribution of higher dimensional Vaidya space-time is equal to zero, while the Møller momentum distribution of higher dimensional Vaidya space-time is not equal to zero.  相似文献   

15.
C. Alexandrou 《中国物理 C》2009,33(12):1093-1101
We present recent lattice results on the baryon spectrum, nucleon electromagnetic and axial form factors, nucleon to △ transition form factors as well as the △ electromagnetic form factors. The masses of the low lying baryons and the nucleon form factors are calculated using two degenerate flavors of twisted mass fermions down to pion mass of about 270 MeV. We compare to the results of other collaborations. The nucleon to △ transition and △ form factors are calculated in a hybrid scheme, which uses staggered sea quarks and domain wall valence quarks. The dominant magnetic dipole nucleon to △ transition form factor is also evaluated using dynamical domain wall fermions. The momentum frame are extracted using the form factors transverse density distributions of the △ in the infinite determined from lattice QCD.  相似文献   

16.
This note concerns the motion of relativistic strings in the Minkowski space R^(1+n). We rederive the general solution formula in closed form for the equation for the motion of relativistic string. Our method is different completely from others.  相似文献   

17.
A more general representation of the Poincare group where translation generators are generalized by Pμ= i∂μ+kγμ[(l+γ5)/2] is discussed. The corresponding spinor gauge field is studied in detail. It is shown that the Lagrangian of fermion keeps its form invariant under the above translation. An additional hidden symmetry of the Dirac field leads to a prediction of existence of an intrinsic energy-momentum for the fernlion.  相似文献   

18.
19.
A new kind of weak Noether symmetry for a general holonomic system is defined in such a way that the methods to construct Hojman conserved quantity and new-type conserved quantity are given. It turns out that we introduce a new approach to look for the conserved laws. Two examples are presented.  相似文献   

20.
Recently, Xiu et al. [Commun. Theor. Phys. 49 (2008) 905] proposed two schemes of teleporting an N particle arbitrary and unknown state when N groups of three particle general W states are utilized a.s quantum channels. They gave the maximal probability of successful teleportation. Here we find that their operation is not the optimal and the successful probability of the teleportation is not maximum. Moreover, we give the optimal schemes operation and obtain maximal successful probability for teleportation.  相似文献   

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