共查询到20条相似文献,搜索用时 15 毫秒
1.
Richard G. Forbes 《Surface science》1978,70(1):239-254
Discrepancies are demonstrated to exist in the conventional mathematical treatment of the charge-exchange model for field evaporation, and a new treatment is presented that concentrates on the behaviour of the atomic nucleus prior to evaporation. The new approach seems physically more correct, produces markedly better agreement with experimental data concerning rate-constant field-sensitivity, and resolves several outstanding puzzles in field evaporation theory. The main numerical achievement is to predict a value of ?6 for the ratio of partial energies . 相似文献
2.
R. Eugene Collins 《Foundations of Physics》1977,7(7-8):475-494
It is shown that the Hilbert space formalism of quantum mechanics can be derived as a corrected form of probability theory. These constructions yield the Schrödinger equation for a particle in an electromagnetic field and exhibit a relationship of this equation to Markov processes. The operator formalism for expectation values is shown to be related to anL
2 representation of marginal distributions and a relationship of the commutation rules for canonically conjugate observables to a topological relationship of two manifolds is indicated. 相似文献
3.
R. P. Malik 《Physics of Particles and Nuclei Letters》2011,8(3):244-250
We derive absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry transformations for the 4D free
Abelian 2-form gauge theory by exploiting the superfield approach to BRST formalism. The antisymmetric tensor gauge field
of the above theory was christened as the “notoph” (i.e. the opposite of “photon”) gauge field by Ogievetsky and Palubarinov
way back in 1966–67. We briefly outline the problems involved in obtaining the absolute anticonimutativity of the (anti-)
BRST transformations and their resolution within the framework of geometrical superfield approach to BRST formalism. One of
the highlights of our results is the emergence of a Curci-Ferrari type of restriction in the context of 4D Abelian 2-form
(notoph) gauge theory which renders the nilpotent (anti-) BRST symmetries of the theory to be absolutely anticommutative in
nature. 相似文献
4.
We propose a new theoretical approach to near-field microscopy, which allows one to deal with scanning tunneling microscopy and scanning near-field optical microscopy with a unified formalism. Under the approximation of weak tip-sample coupling, we show that Bardeen's perturbation formula, originally derived for electron tunneling, can be derived from a scattering formalism which extends its validity to electromagnetic vector fields. This result should find broad applications in near-field imaging and spectroscopy. 相似文献
5.
Arthur Komar 《Foundations of Physics》1985,15(4):473-485
The constraint formalism of classical mechanics is extended to field theories with gauge groups. Explicit examples of Klein-Gordon and Maxwell fields are presented. The symmetry properties of the Maxwell fields have the unexpcted feature in this formalism of forming a first-class algebra which is not Lie, a situation already encountered in the general theory of relativity. 相似文献
6.
7.
Magnetized Rydberg positronium forms when an energetic positron ( e(+)) slows within a tungsten crystal and picks up an electron ( e(-)) as it emerges in a strong magnetic field. The signature is equal numbers of e(+) and e(-) when a weak electric field is applied, either of which can be accumulated and counted. The new e(+) accumulation technique is simple, robust, and much more efficient than any other demonstrated to be compatible with a cryogenic vacuum. Possible applications include the study of cold single component plasmas of e(+) and the formation of cold antihydrogen. 相似文献
8.
R. P. Malik 《The European Physical Journal C - Particles and Fields》2009,60(3):457-470
We derive the off-shell nilpotent Becchi–Rouet–Stora–Tyutin (BRST) and anti-BRST symmetry transformations for all the fields of a free Abelian 2-form gauge theory by exploiting the geometrical superfield approach to the BRST formalism.
The above four (3+1)-dimensional (4D) theory is considered on a (4, 2)-dimensional supermanifold parameterized by the four
even spacetime variables x
μ
(with μ=0,1,2,3) and a pair of odd Grassmannian variables θ and
(with
). One of the salient features of our present investigation is that the above nilpotent (anti-) BRST symmetry transformations
turn out to be absolutely anticommuting due to the presence of a Curci–Ferrari (CF) type of restriction. The latter condition emerges due to the application
of our present superfield formalism. The actual CF condition, as is well known, is the hallmark of a 4D non-Abelian 1-form
gauge theory. We demonstrate that our present 4D Abelian 2-form gauge theory imbibes some of the key signatures of the 4D
non-Abelian 1-form gauge theory. We briefly comment on the generalization of our superfield approach to the case of Abelian
3-form gauge theory in four, (3+1), dimensions of spacetime. 相似文献
9.
It is pointed out that the superoperator formalism, developed for the calculation of ionization potentials in molecular physics, is a very powerful tool in chemisorption theory. This is demonstrated by applying the formalism to the Anderson-Newns model and by showing how the different approximate solutions can be obtained by elegant and systematic procedures. It is also pointed out that using the formalism, solutions for more complicated hamiltonians can easily be obtained. 相似文献
10.
Jerzy Kijowski 《Communications in Mathematical Physics》1973,30(2):99-128
A canonical formalism based on the geometrical approach to the calculus of variations is given. The notion of multi-phase space is introduced which enables to define whole the canonical structure (physical quantities, Poisson bracket, canonical fields) without use of functional derivatives. All definitions are of pure geometrical (finite dimensional) character.The observable algebra
(physical quantities algebra) obtained here is much smaller then the algebra of all (sufficiently smooth) functionals on the space of states, derived from the standard infinite-dimensional formulation. As it is known, the latter is much too large for purposes of quantization. As the examples prove, our algebra
could be an adequate start-point for quantization.For simplifying the language the notion of observable-valued distribution is introduced. Many concrete physical examples are given. E.g. it is shown that some problems connected with gauge in electrodynamics are automatically solved in this approach. The introduced language allows to obtain the Noether theorem in a most natural way. 相似文献
11.
We extend the Einstein-aether theory to include the Maxwell field in a nontrivial manner by taking into account its interaction with the time-like unit vector field characterizing the aether. We also include a generic matter term. We present a model with a Lagrangian that includes cross-terms linear and quadratic in the Maxwell tensor, linear and quadratic in the covariant derivative of the aether velocity four-vector, linear in its second covariant derivative and in the Riemann tensor. We decompose these terms with respect to the irreducible parts of the covariant derivative of the aether velocity, namely, the acceleration four-vector, the shear and vorticity tensors, and the expansion scalar. Furthermore, we discuss the influence of an aether non-uniform motion on the polarization and magnetization of the matter in such an aether environment, as well as on its dielectric and magnetic properties. The total self-consistent system of equations for the electromagnetic and the gravitational fields, and the dynamic equations for the unit vector aether field are obtained. Possible applications of this system are discussed. Based on the principles of effective field theories, we display in an appendix all the terms up to fourth order in derivative operators that can be considered in a Lagrangian that includes the metric, the electromagnetic and the aether fields. 相似文献
12.
A revised formalism of SBS is given based on a new optical nonlinear wave equation which explicitly accounts for the macroscopic spatial inhomogeneity resulting from the induced acoustic wave in the medium. The new equation applies to other scattering phenomena, and more generally to optical wave propagation and interaction in nanostructured media for which characteristic spatial scale lengths of material structures (existing or optically induced) are smaller than the optical wavelength. 相似文献
13.
K. B. Korotchenko 《Russian Physics Journal》1995,38(8):789-791
The paper considers a field equation for representing a microparticle as an extended object constructed from that field (K field). It is shown that in contrast to the equation of an S field (i.e., Schrödinger equation), the boundary-value problem for the K-field equation cannot be used for a unique determination of the parameters of a microparticle in steady states. An auxiliary equation, therefore, is necessary to ensure that the solution of the K -field equation is unique. This is in complete agreement with the physical meaning of K field.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 30–33, August, 1995. 相似文献
14.
15.
It is shown that the application of the Lax-Phillips scattering theory to quantum mechanics provides a natural framework for the realization of the ideas of the Many-Hilbert-Space theory of Machida and Namiki to describe the development of decoherence in the process of measurement. We show that if the quantum mechanical evolution is pointwise in time, then decoherence occurs only if the Hamiltonian is time-dependent. If the evolution is not pointwise in time (as in Liouville space), then the decoherence may occur even for closed systems. These conclusions apply as well to the general problem of mixing of states. 相似文献
16.
17.
I. Ya. Aref'eva
P. B. Medvedev
A. P. Zubarev
《Physics letters. [Part B]》1990,240(3-4):356-362In the framework of the background formalism we analyse possible versions of the Witten-type NSR superstring field theory. We find the picture for string fields to be uniquely fixed by the requirement that the perturbative classical solutions are well-defined. This uniquely defined picture and the corresponding action are different from the ones in Witten's theory and coincide with the ones proposed from different reasons in our previous paper. Following the same background method we calculate the tree-level scattering amplitudes for the new action and argue that in contrast to the ones in Witten's original theory, the amplitudes are singularity-free and hence there is no need to add any tree-level counterterms. We also prove the amplitudes to reproduce correctly the first quantized results. 相似文献
18.
19.
We propose a novel formalism for inflation from a 5D vacuum state which could explain both, seeds of matter and magnetic fields in the early universe. 相似文献
20.
《Nuclear Physics B》1988,295(3):422-442
Matrix field theories (MFT) have recently been used to describe the metal-insulator transition for interacting disordered electrons. With a suitable parametrization of the field we show a correspondence between these models and the usual many-body perturbation theory. By use of this correspondence it is easier to perform two-loop calculations of the physical quantities. For some of these quantities this technique has already been used but not explicitly described. Our task is to put forward in an explanatory way the main aspects of this formalism.As an application we explicitly perform the two-loop expansion of the single-particle density of states (DOS) in the particular case when magnetic impurities are present.Such calculations turn out to be consistent with the prediction of the first order renormalization group (RG) scaling equations. 相似文献