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1.
This is a reprinting of Part 2 of Brandon Carter’s lectures given at the 1972 Les Houches school on black holes, first published in a book of proceedings of that school in 1973, in which the author presents a general theory of stationary black holes. The paper has been selected by the Editors of General Relativity and Gravitation for re-publication in the Golden Oldies series of the journal. Several errors of the original text were corrected for this reprinting by the author. The reprinted article is accompanied by an editorial note written by Marek Abramowicz.  相似文献   

2.
H. Dandache 《Il Nuovo Cimento D》1989,11(10):1501-1506
Summary The semi-empirical Hugoniot equation of state is obtained by using the third-order tangency between the isentropic and the Hugoniot curves at the origin of coordinates. The results of this model are in good agreement with Carter’s experimental data for fourteen elements from the lanthanides series in the lower phase only. Due to postal troubles with Lebanon, it was impossible to send proffs to the author as he requested.  相似文献   

3.
This is a reprinting of the paper by Howard Percy Robertson, first published in 1933 in Rev. Mod. Phys., that is a very authoritative summary of relativistic cosmology at the stage at which it was up to 1933. The paper has been selected by the Editors of General Relativity and Gravitation for re-publication in the Golden Oldies series of the journal. This republication is accompanied by an editorial note written by George Ellis, and by Robertson’s biography, compiled by Andrzej Krasinski from printed sources.  相似文献   

4.
An interpretation of Carter's fourth invariant of the motion is presented and its significance is discussed.  相似文献   

5.
Kontsevich’s formality theorem and the consequent star-product formula rely on the construction of an L -morphism between the DGLA of polyvector fields and the DGLA of polydifferential operators. This construction uses a version of graphical calculus. In this article we present the details of this graphical calculus with emphasis on its algebraic features. It is a morphism of differential graded Lie algebras between the Kontsevich DGLA of admissible graphs and the Chevalley–Eilenberg DGLA of linear homomorphisms between polyvector fields and polydifferential operators. Kontsevich’s proof of the formality morphism is reexamined in this light and an algebraic framework for discussing the tree-level reduction of Kontsevich’s star-product is described. Mathematics Subject Classifications (2000): 53D55, secondary 18G55  相似文献   

6.
This is the second part of a two-part article about ISABELLE, a colliding-beam accelerator conceived in 1971, officially approved in 1978, partially constructed, and terminated in 1983. I cover here the period from ISABELLE’s groundbreaking in 1978 to its termination in 1983. I treat the problems with ISABELLE’s superconducting magnets, the steps by which the problems became clear within the laboratory and to the outside, the initial failure of the laboratory administration to take forceful steps, conflicts with Fermilab, the alternate magnet projects, the repeated missing of openings that eventually used up the window of opportunity. I cover Robert Palmer’s successful creation of an alternate magnet that used Brookhaven’s existing tooling and techniques and provided (too late) a technical solution to the project’s problems, and the name change to the Colliding Beam Accelerator (CBA). I also discuss the failure of the machine to hold the physics community’s interest, and the project’s termination.  相似文献   

7.
This Golden Oldie is a reprinting of a paper by F. A. E. Pirani first published in 1956. It is accompanied by a reprinting of a paper by J. L. Synge first published in 1934. Together these papers pointed the way to the interpretation of geodesic deviation and its relation to the curvature tensor. These two Golden Oldies are accompanied by an Golden Oldie Editorial containing an editorial note written by A. Trautman, and by the biography of F. Pirani written by himself and commented by A. Trautman. An editorial note to this paper and a biography can be found in this issue preceding this Golden Oldie and online via doi:. Original paper: F. A. E. Pirani, Acta Physica Polonica 15, 389–405 (1956). Reprinted with the kind permission of the Editors of Acta Physica Polonica, and of Felix Pirani.  相似文献   

8.
This paper is mainly concerned with elastic and acoustic properties of vitrous silica besides the computation of phonon frequencies. Thus the phonon frequencies of vitrous silica have been calculated assuming the electronic bulk modulus,K e, as equal to zero. New equations have been derived to relate the pressure derivatives of second order elastic constants to the acoustic Gruneisen’s parameters using both Bhatia-Singh’s parameters and Schofield’s equations. The calculated longitudinal and transverse Gruneisen’s parameters and the predicted absorption band spectra from Nagendranath’s equation and Bhatia Singh’s parameters are in good agreement with experiment. The calculated mean acoustic mode Gruneisen’s parameter evaluated from the pressure derivative of Nagendranath’s equation is also in good agreement with experiment. An erratum to this article is available at .  相似文献   

9.
This Golden Oldie is a reprinting of a paper by J. L. Synge first published in 1934. It is accompanied by a reprinting of a paper by F. A. E. Pirani first published in 1956. Together these papers pointed the way to the interpretation of geodesic deviation and its relation to the curvature tensor. These two Golden Oldies are accompanied by an Golden Oldie Editorial containing an editorial note written by A. Trautman, and by the biography of F. Pirani written by himself and commented by A. Trautman. An editorial note to this paper can be found in this issue preceding this Golden Oldie and online via doi:. Original paper: J. L. Synge, Annals of Mathematics 35, 705–713 (1934). Reprinted with the kind permission of the Editors of Annals of Mathematics. J. L. Synge: Deceased 30th March, 1995  相似文献   

10.
Bryce DeWitt was one of the great pioneers of quantum gravity. This unpublished lecture gives his recent views on the topic, which we believe will be of great interest not only to researchers involved in modern attempts to quantize Einstein’s theory, but also to a much wider audience. It is the first installment of a book “The Pursuit of Quantum Gravity 1946–2004; Memoirs of Bryce DeWitt” that Cecile DeWitt is preparing. We would like to thank her for the permission to publish this lecture separately in General Relativity and Gravitation. Readers who have unpublished material such as letters from Bryce, and would be willing to send copies to Cecile, are hereby invited to do so. She would be very grateful. G.F.R. Ellis, H. Nicolai (Editors-in-chief). This article was found in Bryce’s files without references and without an indication of its purpose. References and the name of a previously anonymous student have been supplied by Cecile DeWitt and Brandon DiNunno. Bryce DeWitt (1923–2004). An erratum to this article can be found at  相似文献   

11.
Controlled superdense coding with multi-particle GHZ state and multi-particles GHZ-class state via local measurement are explicitly exploited in this article. The amount of information transmitted from the senders to the receiver is controlled by the supervisor via his local measurement. It is shown that the amount of information is determined by the supervisor’s measurement in the former case of GHZ state, and by the supervisor’s measurement and the coefficients of the original GHZ-class state in the latter case.  相似文献   

12.
Summary The Stahl’s polariton equations for crystals, influenced by a uniform electric field, can be solved by means of an appropriate Green’s function. The Green’s function is calculated for the half-space geometry and the field directed along the z-axis. Using its asymptotic form a formula for the excitonic susceptibility is derived.  相似文献   

13.
Physics in Perspective - The article ‘Einstein’s Gyros’ written by József Illy was originally published electronically  相似文献   

14.
The physical properties of the process of heat transfer from a solar-flare’s energy source (a high-temperature reconnecting current layer) to the surrounding plasma of the Sun’s atmosphere are investigated. Major attention is given to consideration of the collisional relaxation of the heat flux and to analysis of its related effects. The physical meaning of this phenomenon is that the heat flux responds to a change in the spatial temperature distribution with a delay rather than immediately, as in the simplest approximation described by the classical Fourier’s law. It is shown that this mechanism describes the heat transfer in flares better than classical and anomalous heat conduction (see Part 1).  相似文献   

15.
In this paper we pay attention to the inconsistency in the derivation of the symmetric electromagnetic energy–momentum tensor for a system of charged particles from its canonical form, when the homogeneous Maxwell’s equations are applied to the symmetrizing gauge transformation, while the non-homogeneous Maxwell’s equations are used to obtain the motional equation. Applying the appropriate non-homogeneous Maxwell’s equations to both operations, we obtained an additional symmetric term in the tensor, named as “compensating term”. Analyzing the structure of this “compensating term”, we suggested a method of “gauge renormalization”, which allows transforming the divergent terms of classical electrodynamics (infinite self-force, self-energy and self-momentum) to converging integrals. The motional equation obtained for a non-radiating charged particle does not contain its self-force, and the mass parameter includes the sum of mechanical and electromagnetic masses. The motional equation for a radiating particle also contains the sum of mechanical and electromagnetic masses, and does not yield any “runaway solutions”. It has been shown that the energy flux in a free electromagnetic field is guided by the Poynting vector, whereas the energy flux in a bound EM field is described by the generalized Umov’s vector, defined in the paper. The problem of electromagnetic momentum is also examined.  相似文献   

16.
In this paper, a tracking method for optoelectronic imaging platform of tethered balloon based on difference global positioning system/inertial navigation system is presented in detail. The location and attitude information of optoelectronic imaging platform, the azimuth and elevation angles of camera’s line of sight are used by this method to locate the ground target at the centre point of the camera’s field of view through corresponding coordinate transformation. And then, the method makes use of the update position and attitude information to solve the theoretical point of camera’s line of sight inversely. Finally, an angle control commend will be sent to the inertially-stabilized turntable on the optoelectronic imaging platform, which will adjust its azimuth and elevation angle to make the camera’s line of sight to the ground target. A lot of experiments are conducted, and the results show that the initial ground target is always in the centre of camera’s field of view no matter how the balloon’s position and attitude change, and the new location data of ground target has little difference with the initial location data, while the difference between them is close to 0.  相似文献   

17.
Jagmeet Singh 《Pramana》1999,53(5):807-813
Biswas and Soni [4] have surmised a semiclassical formula for Berry’s phase in terms of a generating function. We derive this formula apart from showing that it is not true in general and investigate its domain of validity. We also derive transformation formulae for Berry’s phase (Hannay’s angle) under general canonical transformations. A simpler proof for total angle invariance than hitherto available, is given.  相似文献   

18.
Amitabha Ghosh 《Pramana》1986,27(6):725-730
A quantitative model of inertial induction has been earlier proposed by the author which not only results in the exact equivalence of inertial and gravitational masses but also gives rise to an exceedingly small drag dependent on the velocity with respect to the mean rest frame of the universe. This leads to a cosmological redshift in close agreement with the observation. When this velocity drag due to local interaction is considered it is seen that a significant proportion of the secular retardation of the earth’s spin and the moon’s orbital motion can be attributed to this drag. This also resolves the problem of the moon’s close approach to the earth in the past as suggested by a purely tidal friction theory. The observed large secular acceleration of the Phobos is also explained. The present article shows that local interaction also yields a redshift. When applied to the solar radiation it is seen that the observed supergravity shift at the limb can be very satisfactorily explained.  相似文献   

19.
Classical mechanics is presented so as to render the new formulation valid for an arbitrary temporal variable, as opposed to Newton’s Absolute Time only. Newton’s theory then becomes formally identical (in a precise sense) to relativity, albeit in a three-dimensional manifold. (The ultimate difference between the two dynamics is traced to the existence of the relativistic ‘mass-shell’ condition.) A classical Lagrangian is provided for our formulation of the equations of motion and it is related to one of the known forms of the corresponding relativistic Lagrangian, which is the analogue of the Polyakov Lagrangian of string theory. Dedicated to Emeritus Professor D. Speiser (Université Catholique de Louvain, Belgium) who provided the inspiration for this article.  相似文献   

20.
Dozens of countries are executing national nanotechnology plans. No rigorous evaluation scheme for these plans exists, although stakeholders—especially policy makers, top-level agencies and councils, as well as the society at large—are eager to learn the outcome of these policies. In this article, we recommend an evaluation scheme for national nanotechnology policies that would be used to review the whole or any component part of a national nanotechnology plan. In this scheme, a component at any level of aggregation is evaluated. The component may be part of the plan’s overarching policy goal, which for most countries is to create wealth and improve the quality of life of their nation with nanotechnology. Alternatively, the component may be a programme or an activity related to a programme. The evaluation could be executed at different times in the policy’s life cycle, i.e., before the policy is formulated, during its execution or after its completion. The three criteria for policy evaluation are appropriateness, efficiency and effectiveness. The evaluator should select the appropriate qualitative or quantitative methods to evaluate the various components of national nanotechnology plans.  相似文献   

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