相关论文: Angular momentum of isolated systems
Often it is asserted that only by using of the symmetric Landau-Lifschitz energy-momentum complex one is able to formulate a conserved angular momentum complex in General Relativity ({\bf GR}). Obviously, it is an uncorrect statement. For…
In teleparallelism one is able to tackle the gravitational energy and angular momentum problems in a way that distinguishes this theory from other theories of gravity, such as general relativity. However, unlike the $4$-momentum, the…
We show that the intrinsic angular momentum of matter in curved spacetime requires the metric-affine formulation of gravity, in which the antisymmetric part of the affine connection (the torsion tensor) is not constrained to be zero but is…
For paraxial and non-paraxial light, numerous measures of electromagnetic attribute are expressible in terms of photon annihilation and creation. Accordingly, energy, angular momentum and chirality measures acquire a consistent…
Complex and spinorial techniques of general relativity are used to determine all the states of the $SU(2)$ invariant quantum mechanical systems in which the equality holds in the uncertainty relations for the components of the angular…
The intrinsic angular momentum, or spin, is a cornerstone of modern physics with profound applications from nuclear magnetic resonance to spintronics. While its mathematical structure within quantum theory is well-defined, its fundamental…
A new approach has been used to evaluate the momentum and angular momentum of the isotropic and homogeneous cosmological models. It is shown that the results obtained for momentum exactly coincide with those already available in the…
For a charge-monopole pair, though the definition of the orbital angular momentum is different from the usual one, and the transverse part of the momentum that includes the vector potential as an additive term turns out to be the so-called…
In this note, we transform the linear order (at order $G$) metric from a system of pointlike bodies source in the post-Minkowskian expansion to the Bondi coordinates. We show that the Bondi 4-momentum and angular momentum coincide with the…
Penrose limits are considered in space-times admitting two abelian, space-like Killing vectors in vacuum as well as in the presence of an electromagnetic field. This type of space-times describe inhomogeneous cosmologies as well as…
Creation of angular momentum in a relativistic electron-positron plasma is explored. It is shown that a chain of angular momentum carrying vortices is a robust asymptotic state sustained by the generalized nonlinear Schrodinger equation…
The supertranslation ambiguity of angular momentum is a long-standing problem in general relativity, which arises the puzzle of the angular momentum loss in the post-Minkowskian (PM) expansion. The angular momentum loss in gravitational…
We discuss in depth the application of the classical concepts for interpreting the quantal results from the triaxial rotor core without and with odd-particle. The corresponding limitations caused by the discreteness and finiteness of the…
In condensed matter systems it is necessary to distinguish between the momentum of the constituents of the system and the pseudomomentum of quasiparticles. The same distinction is also valid for angular momentum and pseudoangular momentum.…
The quantum-mechanical description of the collective angular motion in a system of two touching fission fragments is proposed. The main peculiarities of excitation spectrum and the structure of the wave functions are investigated. As found,…
Almost a hundred years ago, two different expressions were proposed for the energy--momentum tensor of an electromagnetic wave in a dielectric. Minkowski's tensor predicted an increase in the linear momentum of the wave on entering a…
Nuclear scissors modes are considered in the frame of Wigner function moments method generalized to take into account spin degrees of freedom and pair correlations simultaneously. A new source of nuclear magnetism, connected with…
The purpose of this note is to point out ambiguities that appear in the calculation of angular momentum and its radiated counterpart when some simple formulae are used to compute them. We illustrate, in two simple different examples, how…
Spinors for an arbitrary Minkowski space with signature ($t$, $s$) are reassessed in connection with $D$-dimensional free Dirac action. The possibility of writing down kinetic and mass terms for charge-conjugated spinors is discussed in…
Orbital angular momentum is a fundamental degree of freedom of light that manifests itself even at the single photon level. The coherent generation and beaming of structured light usually requires bulky and slow components. Using wave…