Related papers: Comments on 'Controversy on a Dispersion Relation …
Considering thermal conduction, compressive viscosity and optically thin radiation as damping mechanisms for MHD waves, we derive a six-order general dispersion relation. We point out a fundamental flaw in the derivation of five-order…
We consider viscosity and thermal conductivity as dissipation mechanisms to derive a general dispersion relation for MHD waves propagating in a homogeneous plasma. We show that the actual dispersion relation for MHD waves in a homogeneous…
In this Comment, we refute conclusions made in Phys. Rev. Lett. 112, 233601 (2014) by L.-G. Wang, L. Wang, M. Al-Amri, S.-Y. Zhu, and M. S. Zubairy. These conclusions stem from the use of the linear theory, which is not applicable to…
Pandey & Dwivedi (2007) again tried to claim that the dispersion relation for the given set of equations must be a sixth degree polynomial. Through a series of papers, they are unnecessarily creating confusion. In the present communication,…
Dispersion relations for the scattering of hadrons are considered within the framework of Quantum Chromodynamics. It is argued that the original methods of proof remain applicable. The setting and the spectral conditions are provided by an…
Kumar et al. (2006) obtained a fifth order polynomial in $\omega$ for the dispersion relation and pointed out that the calculations preformed by Porter et al. (1994) and by Dwivedi & Pandey (2003) seem to be in error, as they obtained a…
It is showed that, in general, classical and quantum dispersion relations are different due to the presence of the Bohm potential. There are exact particular solutions of the quantum (wave) theory which obey the classical dispersion…
We investigate non-contraction of large perturbations around intermediate entropic shock waves and contact discontinuities for the three-dimensional planar compressible isentropic magnetohydrodynamics (MHD). To do that, we take advantage of…
We comment on the recent paper by Srivastava and Dwivedi (J. Astrophs. Astr. {\bf 28}, 1, 2007). In the said paper the derived dispersion relation $\nu \eta \cos^4 \theta k^4 + [v_A^2 - i \omega (\nu + \eta)] \cos^2 \theta k^2 - \omega^2 =…
The quantum theory of relativistic particles, based on the first quantization technique similar to that used by Schroedinger and Dirac in formulating quantum mechanics, is reconsidered on the basis of a photon-like dispersion relation…
Cosmological tensor perturbations equations are derived for Hamiltonian cosmology based on Ashtekar's formulation of general relativity, including typical quantum gravity effects in the Hamiltonian constraint as they are expected from loop…
Deeply Virtual Compton Scattering and electroproduction of mesons involve amplitudes that are analytic in energy. Analyticity enables Dispersion Relations (DR's) for such amplitudes, relating real and imaginary parts. Lately it has been…
In a recent paper [ J. Stat. Mech. P07006 (2004)], E.G.D. Cohen and David Mauzerall (CM) have argued that the derivation of the nonequilibrium work relation given in [C. Jarzynski, Phys. Rev. Lett. 78, 2690 (1997)] is flawed. Here I attempt…
In a recent work, S.A.R. Horsley and coworkers [Nature Photon 9, 436-439 (2015)] showed rather interestingly that planar dielectric media, for which the real and imaginary parts of the dielectric permittivity are related by spatial…
We study the spectral representation and dispersion relations that follow from some basic assumptions and the reduced spacetime symmetries on noncommutative (NC) space. Kinematic variables involving the NC parameter appear naturally as…
An outstanding problem in the study of possible kaon condensation is the striking discrepancy between the results of chiral perturbation theory and those of the PCAC-plus-current-algebra approach. I discuss here what causes this discrepancy…
Sharp uncertainty relations restricting the values of variances in the position space and in the momentum (wavevector) space are derived. They have the same form $\Delta r\Delta k\ge 5/2$ in the classical theory of light beams, in the…
Chandra [1] made an attempt to show that the work of Dwivedi and Srivastava [2] (hereinafter DS) can be investigated even analytically and their results are erroneous. Dwivedi and Srivastava [3] picked up some values of Chandra [1] and…
We derive the dispersion relation for linearized small-amplitude gravity waves for various choices of non-constant vorticity. To the best of our knowledge, this relation is only known explicitly in the case of constant vorticity. We provide…
In a recent Letter, Cummer et al. give a description of material parameters for acoustic wave propagation giving rise to a 3D spherical cloak, and verify the cloaking phenomenon on the level of scattering coefficients. A similar…