81. Reference/Data And Constants Resources - PhysicsWeb physicsWeb, The web site for physicists, physicsWorld, Institute of physics,Electronic Publishing, online products and services. http://physicsweb.org/resources/index.cfm/Reference/Data_and_constants/

Advanced site search resources Resources home What's new Add a link Edit my links ... Advanced resource search quick search Search resources iop resources IOP Select PEERS PhysicsWeb Reference links in this category 3-D Crystal Structures - G.Imbalzano - "La "struttura fine" ¨ una costante termodinamica?" AIF1996 - SIF1998 ABSTRACT. The value of the constant "alpha" is deduced as statistical limit, compatibily with the quantistic hypotesis E=hf and a slight interaction among electric charges. Under these circumstances, in the given system of measure, the Planks constant h= q^2/2c.eps.alpha should assume the slightest value as far possible. jmbalzan@iol.it G.Imbalzano - Moncalieri - ITALY. - The Statistics Division of the American Institute of Physics conducts research and provides survey services. Within the research portion of our mission, we collect, analyze and disseminate data on education and employment in physics and related fields. Acoustooptics database - Site contains information about basic acoustooptics consepts, devices, materials and literature dedicated to this area of physics. Astronomical Data Center ADC Astrophysics Data Facility ADF Atomic Mass Data Center - The AMDC and its electronic bulletin aim at being a meeting place where information on masses experimental, evaluation or theory can be exchanged. All those working on topics related to atomic masses can thus keep the community informed on the latest developments of their own work.

82. When Constants Are Not Constant (October 2001) - Physics World - PhysicsWeb physicsWeb, The web site for physicists, physicsWorld, Institute of physics,Electronic Publishing, online products and services. http://physicsweb.org/articles/world/14/10/4/1

Advanced site search physics world sample issue Request a sample issue browse the archive January February March April May June July August September October November December Latest issue Subscribe to Physics World Media Information ... Editorial Staff quick search Search Physics World Physics World October 2001 When constants are not constant Physics in Action: October 2001 The recent finding by an international team of astronomers that the fine-structure constant has increased over time may support the idea that the universe has extra dimensions. In the movie The Meaning of Life , the Monty Python team reminds us that we live in "an amazing and expanding universe". Ever since the startling evidence for cosmic expansion was discovered in the 1920s, physicists have considered the possibility that the so-called constants of nature - such as the charge on the electron and the gravitational constant - are not constant and may, in fact, vary with time. In the late 1960s, George Gamow suggested that the charge on the electron, e , may vary rather than gravity. More precisely, he considered a variation in the fine-structure constant

83. PSIgate - Hot Topics - Constants And Units http//physics.nist.gov/cuu/constants/. International System of Units (SI) Theofficial SI (Systeme International) website contains information on the use http://www.psigate.ac.uk/newsite/featured_5.html

84. AGU Reference Shelf Online 1 plugin (rather than the browser menu bar.) Global Earth physics FundamentalPhysical constants and Conversion Factors (l-23) ~676KB PDF http://www.agu.org/reference/gephys.html

Order print version This document is published in a searchable PDF format. To search Use the Find feature on your plug-in (rather than the browser menu bar.) Book Contents ~1.8MB PDF Preface MB PDF Contents ~51KB PDF Chapters Astrometric and Geodetic Properties of Earth and the Solar System (l-l) ~2.4MB PDF Charles F. Yoder 1 Geoid, Topography and Distribution of Landforms (l-2) ~751KB PDF Anny Cazenave 32 Earth Tides (l-3) ~765KB PDF John Wahr 40 Global Magnetic Field (l-4) ~1.8MB PDF Jeremy Bloxham 47 Present Plate Motions and Plate Boundaries (1-5) ~1.7MB PDF Richard G. Gordon 66 Seismic Models of the Earth: Elastic and Anelastic (l-6) ~2MB PDF T. G. Masters and P.M. Shearer 88 Free Oscillations: Frequencies and Attenuations (l-7) ~2.3MB PDF T. G. Masters and R. Widmer 104 Seismic Traveltime Tables (l-8) ~1.9MB PDF B. L. N. Kennett 126 Heat Flow of the Earth (l-9) ~2.7MB PDF Carol A. Stein 144 Composition of the Solar System, Planets, Meteorites, and Major Terrestrial Reservoirs (l-10) ~3.4MB PDF Horton E. Newsom 159

85. Physical Constants -- From Eric Weisstein's World Of Physics Units, and Uncertainty Fundamental Physical constants. http//physics.nist.gov/cuu/constants/. Weisstein, EW Books about Physical constants. http://scienceworld.wolfram.com/physics/PhysicalConstants.html

Units and Dimensional Analysis Physical Constants Physics Contributors Romero Physical Constants This entry contributed by Dana Romero Physical constants are constants of nature encountered in physical problems, often also called "fundamental constants." The following table lists some of the more important physical constants. quantity symbol value absolute zero atomic mass unit u atmospheric pressure Avogadro's number Bohr radius for hydrogen Boltzmann's constant k Compton wavelength electron charge e electron mass electron radius Faraday's constant fine structure constant ... gravitational acceleration of free fall g gravitational constant G ideal gas molar volume permeability of free space permittivity of free space Planck's constant h proton mass Rydberg frequency Ry speed of light c Stefan-Boltzmann constant thermal voltage universal gas constant R References Abramowitz, M. and Stegun, C. A. (Eds.). "Physical Constants and Conversion Factors." Ch. 2 in Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing. New York: Dover, pp. 5-8, 1972. Cohen, E. R. and Taylor, B. N. "The Fundamental Physical Constants."

86. Fine Structure Constant -- From Eric Weisstein's World Of Physics Current Advances The FineStructure constants and Quantum Hall Effect. http//physics.nist.gov/cuu/constants/alpha.html. © Eric W. Weisstein http://scienceworld.wolfram.com/physics/FineStructureConstant.html

Modern Physics Quantum Physics Quantum Field Theory General Quantum Field Theory ... Plouffe Fine Structure Constant A dimensionless number that appears in the analysis of quantum electrodynamical Feynman diagrams . It is not currently known if it can be derived from first principals in terms of mathematical constants, but it can be determined as a conglomeration of the electron charge e h-bar ), and the speed of light c . In his later years, the English physicist Arthur Eddington concocted pseudoscientific "proofs" on "physical" grounds that the fine structure constant was exactly 1/136. When experiments yielded a more accurate value, Eddington produced another proof "proving" that In cgs and in MKS where e is the electron charge is the permittivity of free space , and c is the speed of light . Using the best experimental values for e and (the value of c is fixed by definition) gives and The fine structure constant is related through quantum electrodynamics to the gyromagnetic ratio for electron spin by (Sommerfeld 1957, Hughes and Kinoshita 1999), where the second term is given erroneously as

87. Royal Society | Events Diary | The Fundamental Constants Of Physics, Precision M The fundamental constants of physics, precision measurements and SI base units. http://www.royalsoc.ac.uk/event.asp?id=1828&month=2,2005

88. Useful Physics-related Hyperlinks physics Laws Laws, Rules, Principles, Effects, Paradoxes, constants, Experimentsin physics. Time The US Naval Observatory provides precision time from http://www.phy.anl.gov/links_2.html

Useful hyperlinks for physics and chemistry Included below are links to various sites of interest to researchers in physics and chemistry. These include: Scientific Journals Physics Organizations Other Laboratories Sources of Data ... Scientific Software Libraries J ournals Google Scholar Google's search engine for scholarly literature. ANL's Electronic Journals Access to many electronic journals (including all APS journals) and indices via ANL's institutional subscription. ANL libraries' AIM The electronic catalog to search the ANL library system. APL Applied Physics Letters APS Journals Physical Review and Physical Review Letters including author and referee information. AIP Style Manual Fourth Edition (1990) of Institute of Physics Style Manual, a source of guidance in writing, editing, and preparing physics manuscripts for publication. APS Physical Review Focus on-line service that explains selected research articles from the APS journals Cern Courier The Cern Courier is circulated by the IoP. CrossRef Search Institute of Physics CrossRef Search IOP The Institute of Physics Publishing's home page including access to Physics Express Letters an electronic edition of all Letters and Rapid Communications from 11 of IOP's leading journals.

89. The Nobel Prize In Physics 2004 - Information For The Public Progress in particle physics or its relevance for our daily life can sometimes Running coupling constants in the Standard Model (left) and with the http://nobelprize.org/physics/laureates/2004/public.html

HOME SITE HELP ABOUT SEARCH ... EDUCATIONAL English Swedish 5 October 2004 David Gross David Politzer and Frank Wilczek The strong force explained colour interaction David Gross David Politzer and Frank Wilczek discovered a property of the strong interaction which explains why quarks may behave almost as free particles only at high energies. The discovery laid the foundation for the theory for the colour interaction (a more complete name is Quantum ChromoDynamics , QCD). The theory has been tested in great detail, in particular during recent years at the European Laboratory for Particle Physics, CERN, in Geneva. The Standard Model and the four forces of Nature The three forces or interactions, as phycisists prefer to call them, that are applicable to the microcosmos are described by the Standard Model . They are the electromagnetic interaction , the weak interaction and the strong interaction The Standard Model describes quarks, leptons and force-carrying particles. Quarks build, for instance, the protons and neutrons of the atomic nucleus. Electrons that form the outer casing for atoms are leptons and, as far as is known, are not constructed from any smaller constituents. The atoms join up to form molecules, the molecules build up structures and in this way the whole universe can finally be described. High resolution image (jpeg 436 kB) Fig. 1. The four forces (or interactions) of Nature, their force carrying particles and the phenomena or particles affected by them. The three interactions that govern the microcosmos are all much stronger than gravity and have been unified through the Standard Model.

90. THEORETICAL PHYSICS: ON THE FUNDAMENTAL CONSTANTS OVER TIME GENERAL physics ON THE VALUES OF THE FUNDAMENTAL constants Notes by ScienceWeekIn physics, the term fundamental constants (universal constants) refers http://scienceweek.com/2004/sc041119-5.htm

Personal Subscriptions Group Subscriptions Archives Contact Us ... Advertising ScienceWeek Crossing Barriers Since 1997 Receive ScienceWeek three times a week by Email: Subscriptions About ScienceWeek Archives Contact Us ... Subscriptions ScienceWeek THEORETICAL PHYSICS: ON THE FUNDAMENTAL CONSTANTS OVER TIME The following points are made by K.A. Olive and Y-Z. Qian (Physics Today 2004 October): 1) Are any of nature's fundamental parameters truly constant? If not, are they fixed by the vacuum state of the Universe, or do they vary slowly in time even today? To fully answer those questions requires either an unambiguous experimental detection of a change in a fundamental quantity or a significantly deeper understanding of the underlying physics represented by those parameters. 2) At first glance, a long list of quantities usually assumed to be constant could potentially vary: Newton's constant G(subN), Boltzmann's constant k(subB), the charge of the electron e, the electric permittivity epsilon-0, and magnetic permeability mu-0, the speed of light c, Planck's constant h-bar, Fermi's constant G(subF), the fine-structure constant alpha = e^(2)/(h-bar)c and other gauge coupling constants, Yukawa coupling constants that fix the masses of quarks and leptons, and so on. One must, however, distinguish what may be called a fundamental dimensionless parameter of the theory from a fundamental unit. Dimensionless parameters include gauge couplings and quantities that, like the ratio of the proton to electron mass, are combinations of dimensioned quantities whose units cancel. Their variations represent fundamental and observable effects.

91. Spectrum Of Physics - A Physics Directory: Special Relativity, Quantum Theory, E http//britneyspears.ac/physics/constants/constants.htm; Characteristics of PureGases http//physics.nist.gov/cuu/constants/index.html; Metric Prefixes http://www.tardyon.de/links/refer/const.html

Luxon Theory Time Theory copenhagen experiment SPECTRUM OF PHYSICS root top Physical Constants and Astronomical Data http://www.astro.wisc.edu/~dolan/constants.html Atomic Line List v2.04 http://www.pa.uky.edu/~peter/atomic/index.html BritneySpears.ac: Physical Constants http://britneyspears.ac/physics/constants/constants.htm Characteristics of Pure Gases http://www.spectra-gases.com/PureGases/charPureGas.htm Constants Table http://www.ubishops.ca/ccc/div/sci/chem/Constants%20Table.html Fundamental Constants http://www.chembio.uoguelph.ca/educmat/chm386/fundcont.htm Fundamental Physical Constants http://www.chemie.fu-berlin.de/chemistry/general/constants_en.html Fundamental Physical Constants http://www.processassociates.com/process/basics/constants.htm Fundamental Physical Constants from NIST http://physics.nist.gov/cuu/Constants/index.html Metric Prefixes http://www.cchem.berkeley.edu/ChemResources/Weights-n-Measures/metric.html Naturkonstanten http://www.chemie.fu-berlin.de/chemistry/general/constants.html Physical Constants http://nedwww.ipac.caltech.edu/level5/Glossary/lang_formulae.html Physical Constants (1986) http://www.pnc.aps.anl.gov/info/Physical_constants_1986.html

92. Nuclear Physics And The Fundamental Constants Of Nature Nuclear physics and the Fundamental constants of Nature. http://www.phys.washington.edu/users/savage/NucTheory/annual_03/node13.html

Next: Pions in the Pionless Up: Effective Field Theory in Previous: Effective Field Theory in Contents Nuclear Physics and the Fundamental Constants of Nature S.R. Beane and M.J. Savage An effective field theory with consistent power-counting now exists for nuclear processes involving momentum ], which allows one to perform systematic calculations of some nuclear observables. We used it to compute the leading light quark mass, , dependence of observables in the two-nucleon sector, which is a fundamental aspect of strong interaction physics. Partial motivation for this work was the experimental hint that the fundamental constants of nature are time dependent. If this proves to be the case, the predictions of Big Bang Nucleosynthesis (BBN) will differ from present calculations which assume time-independent constants. In order to address BBN in this scenario one needs to know how nuclei and nuclear processes depend upon the constants, including the light-quark masses. We were able to make rigorous predictions for the quark-mass dependence of the deuteron binding energy and the scattering length in the -channel [ ]. It is interesting to note that BBSvK counting [

93. Internet Public Library: Physics The NIST Reference on constants, Units, and Uncertainty http//physics.nist.gov/cuu/index.html A physics reference maintained by theNational Institute of http://www.ipl.org/div/subject/browse/sci54.00.00/

dqmcodebase = "/javascript/" Subject Collections Business Computers Education ... Physics This collection All of the IPL Advanced The science of matter and energy and their interactions. Sub-headings: Astrophysics Where physics and astronomy merge. Atomic and Nuclear Physics Understanding atoms and matter on the smallest scale. Electricity and Magnetism The study of electrical and magnetic forces. Heat and Thermodynamics The study of heat energy and heat transfer. Light, Waves, and Optics The study of visible light and optics, color, sound, and the electromagnetic spectrum. Mechanics The study of forces and motion, kinematics, and projectiles. Modern Physics Relativity and quantum mechanics. Physicists Resources on famous physicists, such as Galileo, Newton, Einstein, and Hawking. Resources in this category: You can also view Magazines Associations on the Net under this heading. arXiv.org e-Print archive http://www.arxiv.org/ "arXiv is an e-print service in the fields of physics, mathematics, non-linear science, computer science, and quantitative biology. The contents of arXiv conform to Cornell University academic standards. arXiv is owned, operated and funded by Cornell University, a private not-for-profit educational institution. arXiv is also partially funded by the National Science Foundation." Center for History of Physics (American Institute of Physics) http://www.aip.org/history/

94. Numerical Constants - Mathematics & Physics - Numericana A catalog of some of the most notable numerical constants in mathematics andother sciences. http://home.att.net/~numericana/answer/constants.htm

home index units counting ... physics Final Answers , Ph.D. Numerical Constants Primary conversion factors between customary systems of units. 6 Basic Dimensionful Physical Constants Proleptic SI Speed of Light in a Vacuum (Einstein's Constant): c = 299792458 m/s. Magnetic Permeability of the Vacuum : An exact value defining the ampere unit. Planck's constant : The ratio of a photon's energy to its frequency. Boltzmann's constant : Relating temperature to energy. Avogadro's number : The number of things per mole of stuff Mechanical Equivalent of Light (683 lm/W at 540 THz) defines the candela Fundamental Mathematical Constants: : Zero is the most fundamental and most misunderstood of all numbers. 1 and -1 : The unit numbers. p ("Pi"): The ratio of the circumference of a circle to its diameter. : The diagonal of a square of unit side. Pythagoras' Constant f : The diagonal of a regular pentagon of unit side. The Golden Number Euler's e : The base of the exponential function which equals its own derivative. ln(2) : The alternating sum of the reciprocals of the integers. Euler-Mascheroni Constant g : The limit of [1 + 1/2 + 1/3 +...+ 1/n]

95. SDL Delphi Component Suite - Common Constants In Physics physics. Index. See also Math constants, Common constants in Chemistry, Commonconstants in Astronomy, Common Measurement Units, Common constants in http://www.lohninger.com/helpcsuite/common_phys_constants.htm

SDL Component Suite 8.2 BasePack UnivConst Physics Index See also: Math constants Common Constants in Chemistry Common Constants in Astronomy Common Measurement Units ... Common Constants in Electromagnetism Common Constants in Physics Identifier Value Units Description kg atomic mass constant J atomic mass constant energy equivalent kg m s bar (pressure) m barn (cross section) J K Boltzmann constant k eV K Boltzmann constant k in eV/K s Curie kg m s dyne kg m s erg kg a s Gauss kg m s gram (force) kg m s inch mercury kg m s inch water kg m s Joule cd sr m Lambert cd sr lumen cd sr m lux kg mass of electron kg mass of muon kg mass of neutron kg mass of proton kg m s Newton (force) cd sr m phot J s Planck constant h eV s Planck constant h in eV s J s Planck constant h/2Pi eV s Planck constant h/2Pi in eV s m Planck length kg Planck mass s Planck time m s speed of light in vacuum kg m s Poise A m magnetic moment of a proton m s rad a s kg Roentgen cd m stilb m s Stokes kg m s Torr Last Update: 2004-Oct-02

96. The Constants Of Nature - Science Articles :: Physics Post Observations like this can wreak havoc on modern physics and make the That theconstants of nature may be varying is indeed an intriguing prospect. http://www.physicspost.com/articles.php?articleId=36

97. Determining Pressure-Dependent Equilibrium Constants - Science Articles :: Physi The equilibrium constant expression will contain the concentrations of the physics Post is proud to be affiliated with the following quality web sites http://www.physicspost.com/articles.php?articleId=103

98. [physics/0110060] Trialogue On The Number Of Fundamental Constants articles on the number of fundamental dimensionful constants in physics. LBO develops the traditional approach with three constants, GV argues in http://arxiv.org/abs/physics/0110060

99. TRIUMF Meetings And Seminars of subatomic physics fundamental constants and the search for New physics . Applications to the determination of physical constants and tests of http://admin.triumf.ca/d2w-pub/seminars/histlist?expand=181

100. Equations Natural Sciences, . Faculty of Natural Sciences Division of physics Astronomy.PHYSICAL QUANTITIES, UNITS and UNIVERSAL constants http://www.herts.ac.uk/astro_ub/a_units.html

PHYSICAL QUANTITIES, UNITS and UNIVERSAL CONSTANTS Physical Quantities SI Units Universal Constants Derived SI Units ... Greek Alphabet A physical quantity is a measurable feature, e.g. wavelength, which must have a numerical value, e.g. 8.01 x 10 and a unit, e.g. m. A version of the metric system, termed the , is the designated universal classification of units. In the SI system a few basic units are arbitrarily defined but chosen to be reasonably practical, e.g. the metre. They are the metre, kilogram, second, ampere, Kelvin, mole, candela. With few exceptions all quantities used in physics can be related to these. SI BASE UNITS Quantity Unit Definition mass kilogram (kg) The mass of a Pt-Ir block kept at an International Bureau in Paris time second (s) Duration of 9,192,631,770 periods of the radiation corresponding to a certain transition of the Cs length metre (m) The distance light travels in a vacuum in 1/299,792,458 second thermodynamic temperature Kelvin (K) The fraction 1/273.16 of the thermodynamic temperature of the triple point of water electric current ampere (A) That constant current in two infinitely long parallel conductors separated by 1 metre which produces a force of 2 x 10 Nm of length of conductor.

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

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