The **electric constant**, or vacuum permittivity, earlier called the absolute
dielectric permittivity and dielectric permittivity of
vacuum, is a physical constant, a scalar quantity that:

- determines the strength and potential of
the electromagnetic field in the classical vacuum;
- is part of the expressions for some laws of
electromagnetism, when they are written in the form corresponding to the
International System of Units (SI).

The electric
constant has the dimension of farad per meter.

**Contents**

- 1 Definition
- 2 Application
- 3 Expression in terms of the vacuum field
parameters
- 4 References
- 5 See also
- 6 External links

**Definition**

The electric
constant is determined with the help of the speed of
light and the magnetic constant
: ^{[1]}

F/m.

**Application**

The electric
constant appears in Maxwell's equations in vacuum, which describe the
properties of electric and magnetic fields, as well as electromagnetic
radiation, and relate the fields with their sources.

In the matter
the material equations of the electromagnetic field are used, while the electric displacement field
**D** is expressed in terms of the electric
constant, the electric field
strength vector **E ** and the polarization density vector **P**:

As a rule, we
can assume that ,
where the quantity represents a tensor and is called electric
polarizability. This expression means that the polarization density vector as a
certain reaction of the matter is generated by the vector of the electric field
strength in the matter, while the directions of these vectors may not coincide.

In the weak
field, the quantity has the special name electric susceptibility and it is almost constant, depending
on the type of matter and its state. In this case we can write:

The product
of the electric constant by the relative permittivity
in this expression is called the absolute
electric permittivity
.

The electric
constant is included in the formulation of the Coulomb's Law, giving the expression
for the force acting between two electric charges:

where is the distance between the charges and . If
is a vector directed from the charge to the charge
, then the force will be the force acting on the charge from the charge . From the expression for the force
we can see that the electric constant in the system of physical units SI
relates the electric charge with the mechanical units, such as force and
distance.

**Expression in terms of the vacuum field parameters**

In the
concept of the force vacuum field ^{[2]} it is assumed that the vacuum
is filled with the fluxes of particles that create gravitational and
electromagnetic forces between the bodies. In particular, the fluxes of charged
particles – praons, moving at
relativistic velocities and transferring their momentum to the charged matter,
are considered to be responsible for emergence of the Coulomb force.

In the model
of cubic distribution of the praons’ fluxes, for the electric constant we
obtain the following: ^{[3]}

Here is the momentum of praons, interacting with
the charged matter; the fluence rate denotes the number of praons dN coming per time dt through the perpendicular to the flux
area dA of one face of the cube, limiting the volume
under consideration; m² is the cross-section of interaction between
praons and nucleons; is the elementary charge;
J/m³ is the
energy density of the praons’ fluxes for cubic distribution.

In the model
of spherical distribution of the praons’ fluxes in space:

where the
fluence rate denotes the number of praons dN coming per time dt from the unit solid angle inside the spherical surface dA; J/m³ is the
energy density of the praons’ fluxes for spherical distribution.

Hence it
follows that the electric constant is a dynamic variable, depending on the parameters
of the vacuum field particles.

**References**

1. CODATA Value: electric constant.
The NIST Reference on Constants, Units, and Uncertainty. US National Institute
of Standards and Technology. June 2015. Retrieved 2015-09-25. 2014 CODATA
recommended values.

2. Fedosin S.G. The Force Vacuum Field as an Alternative to the Ether and
Quantum Vacuum. WSEAS Transactions on Applied and Theoretical
Mechanics, ISSN / E-ISSN: 1991-8747 / 2224-3429, Volume 10, Art. #3, pp. 31-38
(2015).

3. Fedosin S.G. The charged component of
the vacuum field as the source of electric force in the modernized Le Sage’s
model.
Journal of Fundamental and Applied Sciences, Vol. 8, No. 3, pp. 971-1020
(2016). https://dx.doi.org/10.5281/zenodo.845357.

**See**** also**

**External**** links**

·
Fundamental Physical Constants --- Complete
Listing

·
Electric constant in Russian

Source: http://sergf.ru/epen.htm