%I #20 Jul 13 2022 19:07:58

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

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

%U 4,8,1,6,0,6,2,6,5,2,3,3,2,6,0,8,2,5,7,1,8,5,7,7,7,0,4,4,6,8,8,7,0,3

%N Decimal expansion of the Stefan-Boltzmann constant sigma in the 2019 SI system in units Watt/(m^2*K^4).

%C From _Jeremy Tan_, Jun 13 2019: (Start)

%C The Stefan-Boltzmann law states that for a black body with temperature T, its radiant emittance j* (power radiated per unit area) is sigma * T^4.

%C In SI units, all the values in the defining relation in the Formula section are fixed as of May 20 2019 (see the BIPM link), so this constant is also fixed. (End)

%H BIPM, <a href="https://www.bipm.org/utils/common/pdf/CGPM-2018/26th-CGPM-Resolutions.pdf">On the revision of the International System of Units (SI)</a>, BIPM, Nov 13-16 2018.

%H NIST, <a href="http://physics.nist.gov/cgi-bin/cuu/Value?sigma">CODATA Value: Stefan-Boltzmann constant</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_constant">Stefan-Boltzmann constant</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law">Stefan-Boltzmann law</a>

%H <a href="/index/Na">Index entries for natural constants</a>

%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>

%F sigma = 5.6703744... * 10^-8 W m^-2 K^-4

%F Equals A222609*A070063^4/(A003676^3*A003678^2).

%t First@ RealDigits@ N[2 Pi^5 (1380649 10^-29)^4 / (15 (662607015 10^-42)^3 299792458^2), 120] (* _Jeremy Tan_, Jun 13 2019 *)

%Y Fixed SI constants used in deriving this constant: A003676 (h), A003678 (c), A070063 (k).

%K nonn,cons

%O -7,1

%A _Benoit Cloitre_, Apr 10 2003

%E Edited by _Andrey Zabolotskiy_, Jun 23 2017

%E Updated to 2019 SI by _Jeremy Tan_, Jun 13 2019