Home Site Map Search

GeoAstro Applets

Chaos Game

Java

Miscel- laneous

Physics Quiz

Who is Who ?

Astrophysics deutsch  The Mysterious Eddington-Dirac Number Different relations between atomic and cosmic quantities and fundamental constants are leading to the same large number in the order of magnitude of 1040. 1. Forces The electrostatic force between an electron and a proton and the gravitational force have a ratio independent of distance = 2,27·1039 For two electrons the ratio becomes Fc / Fg = 4,2·1042 2. Lengths The "classic electron radius" r can be computed assuming that the energy W=mec2 is equal to the potential energy of the elementary charge e spread over a sphere of radius r: r = 3·10-15 m The ratio of this "elementary length" to the radius of the universe R = 1·1026 m R / r = 3·1040 is a number of the same order of magnitude as in (1). 3. Times The light takes the time t to pass the elementary length t = r / c = 10-23 s This "elementary time" is contained in age of the universe T = 6,2·1017 s by a number of the same order of magnitude as in (1) and (2): T / t = 6·1040 4. Particles The mass M of the universe 2,4·1051 kg to 2,0·1052 kg compared to the mass of a proton mp = 1,67·10-27 kg is the number of protons M / mp = 6·1078 and the number of particles (protons and electrons) is N = 1,2·1080 This is nearly the square of the number found in (1), (2) and (3) ! N = (Fe / Fg)2 = (R / r)2 = (T / t)2 By chance or not ?   Dirac suggested in 1937 that this coincidence could be understood if fundamental constants - in particular, G - varied as the Universe aged.   Fundamental Constants: electron charge e = 1.602·10-19 C electron mass me = 9.109·10-31 kg proton mass mp = 1.673·10-27 kg electric constant 8.854·10-12 As/(Vm) constant of gravitation G = 6.674·10-11 m3/(kg s2) speed of light (vakuum) c = 2.998·108 m/s   Web Links Fundamental Physical Constants (NIST CODATA) [sci.astro] Astrophysics (Astronomy Frequently Asked Questions) (4/9) The Akinetic Principle Basic Units of Physics Dirac's "Coincidences" Sixty Years On Last modified: 2008, Jun 04