A383267 Decimal expansion of (4/11)^(1/3).

7, 1, 3, 7, 6, 5, 8, 5, 5, 5, 0, 3, 6, 0, 8, 1, 7, 0, 6, 7, 1, 8, 9, 9, 9, 9, 1, 7, 6, 2, 6, 6, 1, 2, 4, 7, 5, 9, 0, 7, 9, 6, 5, 4, 7, 5, 8, 9, 0, 3, 8, 0, 6, 6, 9, 1, 5, 6, 2, 6, 7, 5, 2, 0, 8, 4, 5, 8, 3, 1, 4, 7, 0, 6, 7, 7, 1, 8, 7, 5, 6, 4, 6, 3, 2, 4, 0, 3, 3, 9, 9, 3, 2, 2, 6, 8, 1, 7, 1, 7, 2, 4, 4, 6, 4

Offset: 0

Author

Arkadiusz Wesolowski, Apr 21 2025

Keywords

• nonn
• cons
• easy

Comments

In the standard cosmology, the temperature of the free-streaming neutrinos which formed the cosmic neutrino background is (4/11)^(1/3) of the relic photon temperature after the electron-positron annihilation in the early universe (assuming that all electrons and positrons annihilated into photons).

Examples

			0.713765855503608170671899991762661247590796547589038066915626752084583...
		

References

• E. W. Kolb and M. S. Turner, The Early Universe, Addison-Wesley, Redwood City, CA, 1990, p. 503 Appendix A.
• R. E. Lopez, S. Dodelson, A. Heckler and M. S. Turner, Precision detection of the cosmic neutrino background, Physical Review Letters 82 (1999) 3952-3955, p. 3952.
• Steven Weinberg, Gravitation and Cosmology Principles and Applications of the General Theory of Relativity, John Wiley, New York, 1972, p. 537.

Links

• Wikipedia, Cosmic neutrino background.

Crossrefs

Cf. A111728.

Programs

Magma

SetDefaultRealField(RealField(106)); n:=(4/11)^(1/3); Reverse(Intseq(Floor(10^105*n)));

Mathematica

RealDigits[(4/11)^(1/3),10,105][[1]] (* Stefano Spezia, Apr 25 2025 *)

PARI

(4/11)^(1/3)

Formula

Equals 1/A111728 = A005480/A010583.