Journal or Publication Title:

Բյուրականի աստղադիտարանի հաղորդումներ: Երևանի աստղադիտարանի բյուլետեն = Сообщения Бюраканской обсерватории. Бюллетень ереванской Астрономической обсерватории = Contributions from the Burakan observatory. Bulletin of the Erevan astronomical observatory

Date of publication:

2021

Volume:

68

Number:

1

ISSN:

2579-2276

Coverage:

38-49

Abstract:

Using a way of separating the spectral shifts into infinitesimally displaced relative spectral bins and sum over them, we overcome the ambiguity of the parallel transport of four-velocity, in order to give an unique definition of the so-called kinetic relative velocity of luminous source as measured along the observer's line-of-sight in a generic pseudo-Riemannian space-time. The ubiquitous relationship between the spectral shift and the kinetic relative velocity is utterly distinct from a familiar global Doppler shift rule (Synge, 1960). Such a performance of having found a kinetic relative velocity of luminous source, without subjecting it to a parallel transport, manifests its virtue in particular case when adjacent observers are being in free fall and populated along the null geodesic, so that it is reduced to a global Doppler velocity as studied by Synge. We discuss the implications for the instructive case of spatially homogeneous and isotropic Robertson-Walker space-time, which leads to cosmological consequences that the resulting kinetic recession velocity of a galaxy is always subluminal even for large redshifts of order one or more, and thus, it does not violate the fundamental physical principle of causality.

Format:

pdf

Identifier:

oai:arar.sci.am:292917

Language:

en

General note:

Communications of the Byurakan Astrophysical Observatory (ComBAO) is a peer-reviewed scientific journal, which publishes research in observational and theoretical astronomy/astrophysics and presents recent advances in these fields. It is being published by the NAS RA V. Ambartsumian Byurakan Astrophysical Observatory (BAO) in English in electronic form. The journal publishes original papers, review papers, brief reports, book reviews, special communications, observational and theoretical results in various fields of astronomy and related sciences, and some editorial notes, including anniversaries and obituaries. Under the heading “Legacy”, the renewed magazine will republish some old articles of high value in English. The heading “Guest articles” will bring to the attention of readers the articles of researchers who are not employees of BAO. ComBAO was founded in 1946 and regularly published in 1946-1990. However, the publication was interrupted because of the economic situation after the disintegration of the Soviet Union in 1991.

Location of original object:

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