Tully-Fisher relation

The Tully-Fisher relation or The Tully-Fisher law is expression of observations showing that for disk galaxies the fourth power of the circular velocity of stars around the core of the galaxy^[1] is proportional to the luminosity $L$ .^[2] M.Carmeli was able to derive this well-known relation after 5-dimensional modification and extension of Einstein's general theory albeit in fact he showed that the relationship was with the mass of the galaxy which is assumed to relate to its luminosity.^[1] The Tully-Fisher relation is considered to be so reliable in astronomy that it is routinely used to measure the distance to galaxy, because it gives a measure of the brightness of the source.^[1]

The Tully-Fisher relation and halo dark matter

Since $L$ is proportional to the mass $M$ of the galaxy, it follows that the fourth power of the circular velocity is proportional to $M$ . Newtonian mechanics, however, states that the square of the circular velocity is proportional to $M$ . In order to rectify this discrepancy, astronomers assume the existence of halo dark matter.^[2]

References

↑ ^1.0 ^1.1 ^1.2 Hartnett, John (2007). Starlight, Time and the New Physics. Creation Ministries International, 47-54. ISBN 978-0-949-906687. “...Technically, what astronomers are doing is measuring the rotation speeds of the outermost tracer gases on the edge of the disks of stars. In these regions the rotation curves are usually constant as a function of radial distance, so one can imagine this to be a rotation speed for the whole galaxy.”
↑ ^2.0 ^2.1 Silvia Behar, Moshe Carmeli (19 Jul 1999). Derivation of the Tully-Fisher Law from General Relativity Theory: Doubts about the Existence of Halo Dark Matter 1397-1404.

[starlight-1] 1.0 ^1.1 ^1.2 Hartnett, John (2007). Starlight, Time and the New Physics. Creation Ministries International, 47-54. ISBN 978-0-949-906687. “...Technically, what astronomers are doing is measuring the rotation speeds of the outermost tracer gases on the edge of the disks of stars. In these regions the rotation curves are usually constant as a function of radial distance, so one can imagine this to be a rotation speed for the whole galaxy.”

[Dark_Matter-2] 2.0 ^2.1 Silvia Behar, Moshe Carmeli (19 Jul 1999). Derivation of the Tully-Fisher Law from General Relativity Theory: Doubts about the Existence of Halo Dark Matter 1397-1404.

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