Global Journal of Science Frontier Research, A: Physics and Space Science, Volume 23 Issue 1

Global Journal of Science Frontier Research: A Physics and Space Science Volume 23 Issue 1 Version 1.0 Year 2023 Type: Double Blind Peer Reviewed International Research Journal Publisher: Global Journals Online ISSN: 2249-4626 & Print ISSN: 0975-5896 TheHeatTransferbyRadiationunderRelativisticConditions Strictly as per the compliance and regulations of: © 2023. Emil V. Veitsman. This research/review article is distributed under the terms of the Attribution-NonCommercial- NoDerivatives 4.0 International (CC BY-NC-ND 4.0). You must give appropriate credit to authors and reference this article if parts of the article are reproduced in any manner. Applicable licensing terms are at https://creativecommons.org/licenses/by-nc- nd/4.0/. The Heat Transfer by Radiation under Relativistic Conditions By Emil V. Veitsman Abstract- An expression was obtained for the energy density of the moving black-body radiation, i.e., the Stefan-Boltzmann law valid in the interval of object velocities from zero to the velocity of light in vacuo when the angle of observation θ equals zero. The object temperature is shown to comprise two parts. The first one is a scalar invariant under the Lorentz transformations. The second one is a vector depending on the velocity of system motion. The scalar component of the temperature is a contraction of two tensor components of rank 3. Under normal conditions this mathematical object is a scalar. Taking account of a tensor character of the temperature a new formulation is given for the second thermodynamics law. The results obtained are of the great practical importance, in particular, while designing devices to measure the radiation temperature of moving cosmic objects, e.g., quasars. Keywords: heat transfer; radiation; relativistic conditions; temperature; thermodynamics; entropy. GJSFR-A Classification: DDC Code: 621.4022 LCC Code: TJ260