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Physics 8.286: The Early Universe November 13, 2018 Prof. Alan Guth Lecture Notes 7 THE COSMOLOGICAL CONSTANT INTRODUCTION: Much excitement has been generated since January 1998 over observations that show that the expansion of the universe today is accelerating, rather than decelerating. Two
Fundamental Physical Constants — Extensive Listing Relative std. Quantity Symbol Value Unit uncert. u r UNIVERSAL speed of light in vacuum c;c 0 299792458 m s 1 (exact) magnetic constant 0 4π 10 7 N A 2 = 12:566370614::: 10 7 N A 2 (exact) electric constant 1/ 0c2 0 8:854187817::: 10 12 F m 1 (exact) characteristic impedance of vacuum p 0=
The ten dimensionless universal constants to be used here have already been listed at the beginning of §1.1. In this chapter we describe what these constants are. The set of universal constants adopted depends upon the most fundamental physical theory considered. Our ambitions are modest.
Twenty-three of the fundamental physical constants, including the Planck constant, Coulomb constant and the gravitational constant (G), are derived by wave equations based on four, new fundamental constants: wave speed, wavelength, amplitude and density.
Fundamental Physical Constants — Extensive Listing Relative std. Quantity Symbol Value Unit uncert. u r UNIVERSAL speed of light in vacuum c 299792458 m s−1 exact vacuum magnetic permeability 4πα¯h/e 2c µ 0 1.25663706127(20) ×10−6 N A−2 1.6 ×10−10 µ 0/(4π×10−7) 0.99999999987(16) N A−2 1.6 ×10−10 vacuum electric ...
Source: Peter J. Mohr and Barry N. Taylor, CODATA Recommended Values of the Fundamental Physical Constants: 1998, Journal of Physical and Chemical Reference Data, Vol. 28, No. 6, 1999 and Reviews of Modern Physics, Vol. 72, No. 2, 2000.
k k G µ 8.854187817 h Fundamental Physical Constants Quantity Symbol Value Avogadro’s number N A 6.02214129(27) × 10 23 / mol Boltzmann’s constant B 1.3806488(13) × 10 −23 J/K Coulomb constant =1/ 4πε
