Constants

java.lang.Object
- org.jscience.physics.amount.Constants

```
public final class Constants
extends java.lang.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)

Version:

3.1, April 7, 2006

Author:

Jean-Marie Dautelle

Field Summary

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

Method Summary
- Methods inherited from class java.lang.Object
  equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - 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)

Class Constants

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

g

me

mp

mn

md

mμ

π

half_π

two_π

four_π

π_square

c

c_square

k

ℎ

ℏ

e

µ0

ε0

Z0

α

G

N

R

F

σ

amu

Rinf

a0

Eh

Φ0

G0

µB

µN

mP

lP

tP