Condensed Matter

2506 Submissions

[3] viXra:2506.0153 [pdf] submitted on 2025-06-27 02:13:19

The Bragg Law with Radiative Corrections

Authors: Miroslav Pardy
Comments: 10 Pages. Original article

The one-loop radiative corrections to the photon propagator, called vacuum polarization, can be represented by the Feynman diagram of the second order. The physical meaning of this diagram is the virtual proces, where photon can exist in the intermediate state with an electron and a positron being the virtual particles. The photon propagation function based on such process is determined in the framework of he Schwinger source QED methods. Then, the modication of the Brag equation is derived.
Category: Condensed Matter

[2] viXra:2506.0092 [pdf] submitted on 2025-06-17 20:48:30

An Icelandic-English Dictionary and The Graphical Law

Authors: Anindya Kumar Biswas
Comments: 21 Pages. (Note by ai.viXra.org Admin: Further repetition may not be accepted)

We study An Icelandic-English Dictionary, the Second Edition, brought out by the Oxford University Press, way back in the year 1957.We draw the natural logarithm of the number of head words, normalised, starting with a letter vs the natural logarithm of the rank of the letter, normalised. We find that the head words underlie a magnetisation curve. The agnetisation curve i.e. the graph of the reduced magnetisation vs the reduced temperature is the exact Onsager solution of the two dimensional Ising model in the the absence of external magnetic field.
Category: Condensed Matter

[1] viXra:2506.0071 [pdf] replaced on 2026-03-06 16:37:34

Deriving Fermi Arcs of Generic Nature Spanning Nodes Featuring Multibands, Nonlinear Dispersion, And/or Multipoles

Authors: Ipsita Mandal
Comments: 5 Pages. Journal versiom

Fermi arcs appear as the surface states at the boundary of a three-dimensional topological semimetal with the vacuum, reflecting the Chern number ($mathcal C$) of a nodal point in the momentum space, which represents singularities (in the form of monopoles) of the Berry curvature. They are finite arcs, attaching/reattaching with the bulk-energy states at the tangents of the projections of the Fermi surfaces of the bands meeting at the nodes. The number of Fermi arcs emanating from the outermost projection equals $mathcal C$, revealing the intrinsic topology of the underlying bandstructure, which can be visualised in experiments like ARPES. Here we outline a generic procedure to compute these states for generic nodal points, (1) whose degeneracy might be twofold or multifold; and (2) the associated bands might exhibit isotropic or anisotropic, linear- or nonlinear-in-momentum dispersion. This also allows us to determine whether we should get any Fermi arcs at all for $mathcal C = 0$, when the nodes host ideal dipoles.
Category: Condensed Matter