Package org.jscience.physics.amount

Class Constants

java.lang.Object

org.jscience.physics.amount.Constants

public final class Constants
extends Object

This class provides most accurate physical constants measurement; the more accurate the constants, the higher the precision of the calculations making use of these constants.

Constant names use the full range of Unicode characters and are mixed uppercase/lowercase to resemble symbolic names as much as possible

Reference: CODATA Internationally recommended values of the Fundamental Physical Constants (2002)

Field Summary

Fields

Modifier and Type	Field	Description
static final Amount<?>	µ0	Holds the permeability of vacuum or magnetic constant.
static final Amount<?>	µB	Holds the Bohr magneton (ℏ·e/2me)
static final Amount<?>	µN	Holds the nuclear magneton (ℏ·e/2mp)
static final Amount<Length>	a0	Holds the Bohr radius (α/(4π·Rinf))
static final Amount<Mass>	amu	Holds the unified atomic mass unit (0.001 kg/mol)/N
static final Amount<Velocity>	c	Holds the speed of light in vacuum (exact).
static final Amount<?>	c_square	Holds c².
static final Amount<ElectricCharge>	e	Holds the elementary charge (positron charge).
static final Amount<?>	Eh	Holds the Hartree energy (2Rinf·h·c)
static final Amount<?>	F	Holds the Faraday constant (N·e)
static final Amount<Dimensionless>	four_π	Holds 4·π.
static final Amount<Acceleration>	g	Holds the standard acceleration due to gravity (approximately equal to the acceleration due to gravity on the Earth's surface).
static final Amount<?>	G	Holds the Newtonian constant of gravitation.
static final Amount<ElectricConductance>	G0	Holds the conductance quantum (2e²/h)
static final Amount<Dimensionless>	half_π	Holds π/2.
static final Amount<?>	k	Holds the Boltzmann constant.
static final Amount<Length>	lP	Holds the Planck length (ℏ/(mP·c))
static final Amount<Mass>	md	Holds the deuteron rest mass.
static final Amount<Mass>	me	Holds the electron rest mass.
static final Amount<Mass>	mn	Holds the neutron rest mass.
static final Amount<Mass>	mp	Holds the proton rest mass.
static final Amount<Mass>	mP	Holds the Planck mass (ℏ·c/G)1/2
static final Amount<Mass>	mμ	Holds the muon rest mass.
static final Amount<?>	N	Holds the Avogadro constant.
static final Amount<?>	R	Holds the molar gas constant (N·k)
static final Amount<?>	Rinf	Holds the Rydberg constant (α²·me·c/2h).
static final Amount<Duration>	tP	Holds the Planck time (lP/c)
static final Amount<Dimensionless>	two_π	Holds 2·π.
static final Amount<ElectricResistance>	Z0	Holds the characteristic impedance of vacuum (µ0·c).
static final Amount<MagneticFlux>	Φ0	Holds the magnetic flux quantum (h/2e)
static final Amount<Dimensionless>	α	Holds the fine structure constant (e²/(2·ε0·c·h))
static final Amount<?>	ε0	Holds the permittivity of vacuum or electric constant (1/(µ0·c²))
static final Amount<Dimensionless>	π	Holds the ratio of the circumference of a circle to its diameter.
static final Amount<Dimensionless>	π_square	Holds π².
static final Amount<?>	σ	Holds the Stefan-Boltzmann constant ((π²/60)·k4/(ℏ³·c²))
static final Amount<?>	ℎ	Holds the Planck constant.
static final Amount<?>	ℏ	Holds the Planck constant over 2π.

Method Summary

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

g

public static final Amount<Acceleration> g

Holds the standard acceleration due to gravity (approximately equal to the acceleration due to gravity on the Earth's surface).

See Also:

• Wikipedia: Acceleration due to gravity

me

public static final Amount<Mass> me

Holds the electron rest mass.

mp

public static final Amount<Mass> mp

Holds the proton rest mass.

mn

public static final Amount<Mass> mn

Holds the neutron rest mass.

md

public static final Amount<Mass> md

Holds the deuteron rest mass.

mμ

public static final Amount<Mass> mμ

Holds the muon rest mass.

π

public static final Amount<Dimensionless> π

Holds the ratio of the circumference of a circle to its diameter.

half_π

public static final Amount<Dimensionless> half_π

Holds π/2.

two_π

public static final Amount<Dimensionless> two_π

Holds 2·π.

four_π

public static final Amount<Dimensionless> four_π

Holds 4·π.

π_square

public static final Amount<Dimensionless> π_square

Holds π².

c

public static final Amount<Velocity> c

Holds the speed of light in vacuum (exact).

c_square

public static final Amount<?> c_square

Holds c².

k

public static final Amount<?> k

Holds the Boltzmann constant.

See Also:

• Wikipedia: Boltzmann constant

ℎ

public static final Amount<?> ℎ

Holds the Planck constant.

See Also:

• Wikipedia: Plank's constant

ℏ

public static final Amount<?> ℏ

Holds the Planck constant over 2π.

e

public static final Amount<ElectricCharge> e

Holds the elementary charge (positron charge).

See Also:

• Wikipedia: Elementary Charge

µ0

public static final Amount<?> µ0

Holds the permeability of vacuum or magnetic constant.

See Also:

• Wikipedia: Permeability (electromagnetism)

ε0

public static final Amount<?> ε0

Holds the permittivity of vacuum or electric constant (1/(µ0·c²))

See Also:

• Wikipedia: Permittivity

Z0

public static final Amount<ElectricResistance> Z0

Holds the characteristic impedance of vacuum (µ0·c).

α

public static final Amount<Dimensionless> α

Holds the fine structure constant (e²/(2·ε0·c·h))

See Also:

• Wikipedia: Fine Structure Constant

G

public static final Amount<?> G

Holds the Newtonian constant of gravitation.

See Also:

• Wikipedia: Gravitational Constant

N

public static final Amount<?> N

Holds the Avogadro constant.

See Also:

• Wikipedia: Avogadro's number

R

public static final Amount<?> R

Holds the molar gas constant (N·k)

See Also:

• Wikipedia: Gas constant

F

public static final Amount<?> F

Holds the Faraday constant (N·e)

See Also:

• Wikipedia: Faraday constant

σ

public static final Amount<?> σ

Holds the Stefan-Boltzmann constant ((π²/60)·k⁴/(ℏ³·c²))

amu

public static final Amount<Mass> amu

Holds the unified atomic mass unit (0.001 kg/mol)/N

Rinf

public static final Amount<?> Rinf

Holds the Rydberg constant (α²·me·c/2h).

See Also:

• Wikipedia: Rydberg constant

a0

public static final Amount<Length> a0

Holds the Bohr radius (α/(4π·Rinf))

Eh

public static final Amount<?> Eh

Holds the Hartree energy (2Rinf·h·c)

Φ0

public static final Amount<MagneticFlux> Φ0

Holds the magnetic flux quantum (h/2e)

G0

public static final Amount<ElectricConductance> G0

Holds the conductance quantum (2e²/h)

µB

public static final Amount<?> µB

Holds the Bohr magneton (ℏ·e/2me)

µN

public static final Amount<?> µN

Holds the nuclear magneton (ℏ·e/2mp)

mP

public static final Amount<Mass> mP

Holds the Planck mass (ℏ·c/G)^1/2

lP

public static final Amount<Length> lP

Holds the Planck length (ℏ/(mP·c))

tP

public static final Amount<Duration> tP

Holds the Planck time (lP/c)