Talk:Gravitational coupling constant

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Just why is it that this dimensionless number, unlike the fine structure constant, commands so little attention in modern physics?? The strong force coupling constant is mentioned even less.202.36.179.65 21:59, 7 April 2006 (UTC)

[edit] More from Barrow and Tipler (1986)

I had the temerity to create this entry even though I have never taken a university class in physics. Hence edits to this entry, and criticisms posted on this talk page, by trained physicists are most welcome. My fascination with this topic began when a physics grad student first told me about the "weird number 137." Years later, I realised he had the fine structure constant in mind. Later yet, I discovered Barrow and Tipler (1986), the only extended discussion in print I've found on the subject of this entry, and later yet the easier Barrow (2002).

According to (4.5) and (4.6) in Barrow and Tipler, Eddington concluded that the physics of his day was grounded in the fine structure constant, α, and three dimensionless numbers resulting from dividing m_e by (unlike B&T, I assume Planck units):

m_N = 1/β (β ≈ 1836 is the usual ratio);
e (this ratio subsumes the subject of this entry);
Hubble's constant times the square root of the cosmological constant.

α and β suffice for QED. The other two constants matter for cosmology.

Barrow and Tipler go on to define dimensionless constants, analogous to the fine structure constant, for the:

Weak force (p. 354), = G_F (Fermi coupling constant) x m_e²;
Strong force (5.72), = Yukawa coupling constant / 4π ≈ 0.2.

A curiosum. 1836x137 requires 17 binary digits to express. The prime factorization of 1836 = 2²x3³x17. 137 is prime. 202.36.179.65 18:09, 15 April 2006 (UTC)