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The formula for this relation is Luminosity = Mass^3.5

Taking logs of both sides we get log (lum) = 3.5 * log (mass)

and using a little algebra we find that the exponent (3.5) should equal log (lum) ÷ log (mass)

I have selected stars from a table located here: http://www.essex1.com/people/speer/main.html [Broken]

and I have computed what the exponent value should be in each case.

STAR Lum Mass EXP

Orionis C 30,000.00 18.00 3.566653

Becrux 16,000.00 16.00 3.491446

Spica 8,300.00 10.50 3.837759

Achernar 750.00 5.40 3.925568

Rigel 130.00 3.50 3.885439

Sirius A 63.00 2.60 4.336039

Fomalhaut 40.00 2.20 4.678604

Altair 24.00 1.90 4.951367

Polaris A 9.00 1.60 4.674910

Eta Scorpii 6.30 1.50 4.539354

Procyon A 4.00 1.35 4.619371

Alpha Centauri A 1.45 1.08 4.827943

The Sun 1.00 1.00

Mu Cassiopeiae 0.70 0.95 6.953637

Tau Ceti 0.44 0.85 5.051600

Pollux 0.36 0.83 5.483033

Epsilon Eridani 0.28 0.78 5.123395

Alpha Centauri B 0.18 0.68 4.446371

Lalande 21185 0.03 0.33 3.162872

Ross 128 0.0005 0.20 4.722706

Wolf 359 0.0002 0.10 3.698970

No matter whether we concentrate on low mass or high mass stars, we see that the exponent value varies quite a bit .

Does anyone know why there is so much variance in the mass luminosity relation?

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# Mass Luminosity relation doesn't hold true when applied to actual data

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