The determination of best values of the fundamental physical constants

2005 ◽  
Vol 363 (1834) ◽  
pp. 2105-2122 ◽  
Author(s):  
Barry N Taylor
Keyword(s):  
Least Squares ◽  
Science And Technology ◽  
Fundamental Constants ◽  
Fundamental Physical Constants ◽  
Physical Constants ◽  
Self Consistent ◽  
Modern Physics ◽  
Least Squares Adjustment ◽  
Fundamental Physical

The purpose of this paper is to provide an overview of how a self-consistent set of ‘best values’ of the fundamental physical constants for use worldwide by all of science and technology is obtained from all of the relevant data available at a given point in time. The basis of the discussion is the 2002 Committee on Data for Science and Technology (CODATA) least-squares adjustment of the values of the constants, the most recent such study available, which was carried out under the auspices of the CODATA Task group on fundamental constants. A detailed description of the 2002 CODATA adjustment, which took into account all relevant data available by 31 December 2002, plus selected data that became available by Fall of 2003, may be found in the January 2005 issue of the Reviews of Modern Physics . Although the latter publication includes the full set of CODATA recommended values of the fundamental constants resulting from the 2002 adjustment, the set is also available electronically at http://physics.nist.gov/constants .

scholarly journals Fundamental physical constants: looking from different angles

2005 ◽  
Vol 83 (8) ◽  
pp. 767-811 ◽  
Author(s):  
S G Karshenboim
Keyword(s):  
Fundamental Physical Constants ◽  
Physical Constants ◽  
Modern Physics ◽  
Fundamental Physical

We consider fundamental physical constants that are among a few of the most important pieces of information we have learned about Nature after intensive centuries-long study. We discuss their multifunctional role in modern physics including problems related to the art of measurement, natural and practical units, the origin of the constants, their possible calculability and variability, etc.PACS Nos.: 06.02.Jr, 06.02.Fn

scholarly journals DISCRETE QUANTUM GRAVITY: A MECHANISM FOR SELECTING THE VALUE OF FUNDAMENTAL CONSTANTS

2003 ◽  
Vol 12 (09) ◽  
pp. 1775-1781 ◽  
Author(s):  
RODOLFO GAMBINI ◽  
JORGE PULLIN
Keyword(s):  
Quantum Gravity ◽  
Selection Process ◽  
Einstein Equations ◽  
Fundamental Constants ◽  
Fundamental Physical Constants ◽  
Physical Constants ◽  
Random Fashion ◽  
The One ◽  
The Universe ◽  
Fundamental Physical

Smolin has put forward the proposal that the universe fine tunes the values of its physical constants through a Darwinian selection process. Every time a black hole forms, a new universe is developed inside it that has different values for its physical constants from the ones in its progenitor. The most likely universe is the one which maximizes the number of black holes. Here we present a concrete quantum gravity calculation based on a recently proposed consistent discretization of the Einstein equations that shows that fundamental physical constants change in a random fashion when tunneling through a singularity.

scholarly journals ON THE ISSUE OF STUDYING FUNDAMENTAL PHYSICAL CONSTANTS

2020 ◽  
Author(s):  
M. Volkova ◽  
Keyword(s):  
Fundamental Constants ◽  
Fundamental Physical Constants ◽  
Physical Constants ◽  
Fundamental Properties ◽  
The World ◽  
Fundamental Physical

The article analyzes the most profound and fundamental properties of the world around us, manifested in the sense of fundamental physical constants. The stages of studying and forming ideas about fundamental constants are considered.

Possible new definitions of the kilogram

2005 ◽  
Vol 363 (1834) ◽  
pp. 2249-2264 ◽  
Author(s):  
R.S Davis
Keyword(s):  
International System ◽  
Fundamental Constants ◽  
Planck Constant ◽  
Fundamental Physical Constants ◽  
Target Uncertainty ◽  
Long Term Stability ◽  
Modern Physics ◽  
Newtonian Constant ◽  
Fundamental Physical

Summary The kilogram is the unit of mass in the International System. Its definition dates from 1889 and, therefore, predates most of modern physics. The definition simply states that the ‘kilogram’ is the mass of an object known as the international prototype. Thus, we have the extraordinary situation that certain fundamental physical constants (the Planck constant, the Newtonian constant of gravitation, the mass of an electron, the mass of an atom of carbon-12, etc.) are measured in terms of an artefact that was manufactured in the nineteenth century. We begin by describing what is presently known about the long-term stability of artefact standards and how this stability can be experimentally monitored with respect to fundamental constants of physics. Finally, we suggest that present experiments are close to achieving the target uncertainty of the order 10 −8 , although the current incoherence between two classes of experiments is cause for concern.

The fundamental constants and theory

2005 ◽  
Vol 363 (1834) ◽  
pp. 2123-2137 ◽  
Author(s):  
Peter J Mohr
Keyword(s):  
Experimental Data ◽  
Least Squares ◽  
Science And Technology ◽  
Fundamental Constants ◽  
Conversion Factors ◽  
Self Consistent ◽  
Theoretical Predictions

The Committee on Data for Science and Technology has recently recommended a new self-consistent set of values of basic constants and conversion factors of physics and chemistry. These values are based on a least-squares analysis that takes into account all of the latest relevant experimental and theoretical information in a consistent framework. Theory plays a role, because the experimental data are compared to the corresponding theoretical predictions which are functions of the fundamental constants. The best values of the constants are taken to be those that give the best agreement between the data and these predictions, in the least-squares sense. An overview of the calculations that influence the recommended values of the constants will be given.

Sign in / Sign up

Export Citation Format

Share Document