It is also known, that the existence of magnetic moment is expected for charged particles [
17,
18] and it influences the value of the electromagnetic force [
19,
20]. It will be therefore shown in
Section 2.2, that the use of the energy-momentum tensor for the system in form of Alena Tensor (denoted as
) leads directly to the conclusion that charged particles should have spin and the energy of the particles results from the existence of energy of magnetic moment. For this reason, the energy of charged particles will also turn out to be part of the Poynting four-vector and the previously obtained relationship between four-momentum and derived gauge of electromagnetic four-potential (
A24) will be clarified. The presence of the charged matter energy density in the Poynting four-vector can be already seen by analyzing the first row of the classical energy-momentum tensor of electromagnetic field
(
A4) in flat spacetime, which using conclusion (
A6) can be alternatively expressed as
In above
represents the energy density of electromagnetic field and from (
A27) it is known, that
thus
and
are positive, so the above equation represents the components of the Poynting four-vector. However, the connection of
with the energy density of magnetic moment requires more detailed explanation in
Section 2.2.
2.1. Interpretation Of The Four-Force Densities In Flat Spacetime
Using (
1), one may define relative permeability
and volume magnetic susceptibility
as
thanks to which the Alena Tensor (
A6) in flat spacetime takes the form expected for the system with electromagnetic field
It now may be noticed, that there are present in the system (
A17) only two four-force densities: related to gravity
according to (
A26) equal to
and electromagnetic corrected by the
coefficient
Introduced
allows for the interpretation of the applied correction to the electromagnetic four-force density, linking the presence of relative permeability with the existence of energy density of matter. In the limit for
Alena Tensor simply becomes a tensor of the electromagnetic field
and pressure
. Therefore
may be actually associated with the negative pressure of a vacuum, filled with an electromagnetic field. In the limit
one obtains
and forces caused by field disappear. The meaning of this boundary solution requires further analysis.
Using (
A33), (
A35), (
A37) and definition of the pressure (
A5) one may notice, that considering point-like particles one obtains
where H is Hamiltonian for point-like particle,
is pressure-volume work and there is relation of the pressure p (
A5) in the system to the energy of the field
contained in the system. It thus also becomes possible to interpret the correction for the electromagnetic force discussed in (
6) considering point-like particles, where now relative permeability
and derived gauge of electromagnetic four-potential
(
A24) are
As one may notice from (
7) and (
A37), the increasing energy of an accelerated body cannot take energy from nowhere. Considering H as conserved energy in a closed system, one gets that
increases at the expense of decreasing
in the system. Therefore, also forces resulting from descreasing
must at some point decrease and for
the body cannot accelerate any more. Assuming classical relation between permeability
and permittivity
one also gets that relative permittivity
and the electric susceptibility
are
As may be seen,
acts as a negative correction to four-force densities (as
increases at the expense of
) and upholds the principle of conservation of energy. It means, that discussed
reproduces Abraham–Lorentz effect. This also shows that for the static, symmetric case with radial coordinate r, the distributions of
in flat spacetime should satisfy the conditions
which allows to analyze the four-force density
.
The Alena Tensor in curved spacetime transforms into EFE (
A13) with the cosmological constant related to
(
A14), (
A3), but above conclusions allow already for the interpretation of
in flat spacetime with a negligible electromagnetic force. At first, one may start with Newtonian approximation. It is known, that classical Newtonian force does not describe many phenomena described by GR equations (e.g., frame-dragging), but it may be treated as illustrative approximation and may be sufficient for some applications in cosmology. It will also allow to explain the relationship between the
that describes the behavior of gravity and the
factor that affects the value of the electromagnetic force. Therefore, considering the simplest case of a test body near the spherical gravity source of mass M and assuming Newtonian approximation in compliance with the condition (
11) one obtains
For a test body in a fixed position from the source of gravity (stationary observer with
and in more general case
above may be simplified to the classical Newtonian approximation with opposite sign. As can be seen from (
12), the
does not represent the four-force density of gravity itself, but the four-force density against gravity, resulting from the motion of a considered test body. Indeed, gravity is not a force what is direct consequence of GR. Four-force density
represents therefore effects of centrifugal force and all other phenomena related to the effects caused by the motion of a test body in a physical system with gravity, because any movement other than free fall is an action against gravity.
When considering
in general form (
5), according to the equivalence principle, it must be assumed that for free fall
vanishes. To improve the clarity of the equations and ensuring property (
11) for simple radial case, one may at first introduce variable
, such that
Next, denoting the free fall velocity as
, from simple calculations, equivalence principle therefore yields
where equality related to
comes from (
3), since
is field tensor invariant, thus
. As one may easy calculate, with the above condition, in free-fall
four-force density
actually vanishes. It can also be expected, that
should be related to the effective potential and for circular orbits
should vanish.
The above problem seems complex, but since we are in flat spacetime, one may find a simple solution. The reader who uses GR equations in curved spacetime may be accustomed to using the stationary observer’s coordinate time at infinity
. Since we are in flat spacetime, in all the equations it is used
associated with the four-position
what opens some opportunity. To begin with, one may propose a general solution, using the Lorentz factor
as an example, defining it as below and using some unknown function
where above requests that
. The above example shows the meaning of representing motion along a geodesic in flat spacetime and why a body moving with velocity
does not experience acceleration visible in (
15) as
. Bodies in the system move under the influence of gravity and as a final result of the movement of bodies, the acceleration also changes
, as one should expect in a real, dynamic solution. In order for the body not to feel the acceleration, it is enough to ensure that
describes the ratio of the t and the proper time
of stationary observers, always stationary in respect to the gravitational source (observers putting in the work to stay at a fixed point from the source of gravity)
where
describes the ratio of the elapsed time between a stationary observer at infinity and an observer in the frame of the test body possessing angular momentum. As will be shown later in this section, this assumption actually leads to the correct results, allowing the GR-induced motion along a geodesic in curved spacetime to be reproduced in flat spacetime. With this assumption, the gradient on
cannot actually change and as a result, Equation (
16) makes
invariant
.
To find solutions for stationary sources of gravity corresponding to the GR metrics, one must however assume, that because the source of gravity is stationary, which means, that in stationary cases gravitational acceleration must be treated as invariant. It is possible to create solution in such stationary approach, ensuring vanishing for free-fall.
At first, only radial free fall can be analyzed. For a symmetric, stationary, non-rotating source of gravity one may consider stationary observers as being accelerated by an invariant acceleration
, passed by a freely falling body moving only in radial axis with a radial velocity
opposite to theirs, where total displacement may be denoted as
s. The description of such free-fall, yields
where for such definition of
for only radial move one obtains
thus (
14) yields
As can be easily noticed, for
where
is Schwarschild radius, one gets a flat spacetime description with the force "against gravity" for purely radial motion (lack of angular momentum) corresponding to Schwarschild metric, where for a body with
velocity, four-force density
vanishes. In the above description, the Schwarzschild radius corresponds to the total path traveled by, in fact, stationary observers counteracting gravity. However, this is only a side effect of the assumptions made for the static solution, where
is actually the path "not traveled" by a radially falling body in free fall towards the point
. It is also worth noting that the considered above dependence of
on t, in general, is essentially necessary to allow for the existence of Hawking radiation in Schwarschild case [
21]. Without such dependence, the mass of the gravitational source remains constant, which would prevent any energy from being radiated.
For a description of the motion of any test body, the mentioned above simple radial acceleration relative to a stationary observer is no longer sufficient. However, according to (
16) with known effective potential resulting from Schwarschild metric [
22] and assuming
L to be the normalized angular momentum
where auxiliary variables a and b are defined as follows
Since in the limit of radial motion L vanishes, therefore in order to be consistent with previously considered radial-only case with
as in (
18) it must hold
thus for circular orbits
Obtained in this way
with
defined in (
20) is an exact, flat spacetime description reproducing Schwarzschild metric preserving all the properties of the curvilinear description and shedding new light on the interpretation of gravity described by this metric. For example:
four-force density vanishes only for and
case represents circular orbit and in this case what indicates that and L does not change in time
in all other cases L must be time dependent, since which means that the body lose angular momentum as it moves around the source of gravity
the energy lost in this way must be radiated in the form of gravitational waves, which de facto agrees with the general knowledge about GR
bodies on orbits with must in fact slowly spiral toward the source of gravity
By transforming the GR description into the flat spacetime description, the total relativistic four-force
visible in (
5) takes into account
distribution and the relative four-velocity of the bodies in order to provide property
, reflect the complexity of the results obtained using GR and retain the conclusion that gravity is not a force, preserving equivalence principle. Therefore, obtained from Alena Tensor relativistic four-force density
, opens a new way to test different
distributions describing gravity in flat spacetime, which may also help in the analysis of GR solutions, extending present knowledge. The reasoning presented in this section can be used to reproduce gravity in flat spacetime also for gravity described by other metrics in curved spacetime. It can also be noticed that for radial free-fall, even below the Schwarzschild radius, coefficients
and
have analyzable imaginary values, representing a certain wave functions, which can be seen in
Figure 1 below.
The above preliminary conclusions require further research and in-depth analysis for
in flat spacetime corresponding to other metrics in curvilinear description. However, these conclusions are sufficient to make an analysis of the equation (
4) from the perspective of electromagnetism, because, as one may notice, the energy-momentum tensor for the electromagnetic field
with
(related to
) defined in a similar way as in (
17) also for other types of gravity sources, has analyzable values both above and below the event horizon. This analysis will be performed in the next section.
Finally, it is worth noting that since four-force density associated with the Einstein tensor (accurate to a constant) in (
A19), may be expressed in flat spacetime as
therefore
, maintaining the principle of conservation of energy, must prevent non-physical effects such as black hole singularity. This can be seen by analyzing (in a classical way used for GR), solutions of (
A13) in curved spacetime for the static, symmetric case, as these are smooth de Sitter solutions [
23], free of singularities, however, this topic deserves to be developed in a separate article.
The interpretation presented in this section, introduces also new possibilities regarding the interpretation of the dark sector, which will be discussed later in the article.
2.2. Interpretation Of The System From The Perspective Of Electromagnetism Theory
Staying with the description for a flat spacetime with an electromagnetic field, denoting the electric and magnetic fields as
and
and denoting the densities of electric and magnetic energy occurring in the electromagnetic field tensor as
it can be seen from (
A3) that
Therefore using conclusion (
A30), the relationship between magnetic energy density and the energy density of the electromagnetic field
can be written as
Thanks to the above, the four-potential of the electromagnetic field from conclusion (
A24) can be simplified to
For a charged particle at rest, the above reduces to a scalar
expressing (negative) classical value of magnetic energy density and zero vector, but completely stationary cases must be excluded, because they lead to
. The above equation thus also says, that even in the absence of orbital angular momentum, the charged particle must vibrate or rotate and experience a magnetic field, because without the magnetic field, the entire four-potential vanishes. In fact, it will be shown later in this section, that the above four-potential results from the existence of magnetic moment and magnetization itself is the source of the electric field of quasi-stationary charged particles.
Using four-current
from (
A29), the source of the electric field associated with charged matter can now be represented, as reduced (compared to the classical value) magnetic energy density
where
is volume magnetic susceptibility from (
3). In the above description, the
coefficient seems to be related to some intrinsic, internal volume magnetic susceptibility of charged matter, so one may take a closer look at this phenomenon. The value preserved in the system (
A27) must be also conserved for the electromagnetic energy densities associated with charged matter
where according to (
29), (
A5) and above, electric energy density associated with matter
may be denoted as
The above leads directly to the conclusion that total electromagnetic field energy density may be expressed as electric field energy density related to charged matter and the energy density of magnetic moment. It may be seen by calculating energy density of the electromagnetic field
In above, last component of the equation represents the classical description of the energy density of magnetic moment, where
serves as volume magnetic susceptibility. Therefore, the electromagnetic field associated with density of charged matter will be most easily described as a propagating disturbance of magnetization and polarization, because the combination of magnetization and polarization describes such electric currents [
24] and relativistic tensor can be created based on them [
25]. According to classical electromagnetism rules, by decomposing electromagnetic field tensor into Polarization-Magnetization tensor
and Electric Displacement tensor
one obtains
where
and
are related by volume magnetic susceptibility coefficient. Although the general form of the
and
equivalents for the energy-momentum tensors is unknown, one may build two symmetrical energy-momentum tensors, where a division of the stress-energy tensor of electromagnetic field will be obtained, into a tensor representing magnetization-polarization related to charged matter (being the source of the field), and energy-momentum tensor representing electric energy transmission. Next, one may show, that the above leads directly to obtaining the classical equivalent of quantum interpretation seen in QED.
To clarify the above statement one may multiply equation (
A6) by
from (
3) to get
In above
what gives first component, describing distribution of magnetic moment. Next, using volume magnetic susceptibility
from (
3) one may introduce the symmetric energy-momentum tensor
defined as
where last transformation of the equation comes from (
A31), and where according to (
A25) above yields
what yields
This shows, that
can be understood as some description of the density of charged matter, experiencing only electromagnetic force. Component
in Equation (
36) represents classical relation between Polarization-Magnetization tensor and Electric Displacement tensor, where
so, by analogy to (
28),
may be also understood as the rank two tensor potential of the electromagnetic field associated with charged matter. All that remains, is to introduce rank two tensor volume magnetic susceptibility
according to the rules of classical electrodynamics
defined in such a way, that
where
seems to be responsible for the self-interaction, resulting in the formation of internal magnetic moments - vortex field associated with elementary particles.
Summarizing, may be considered as Polarization-Magnetization energy-momentum tensor, describing distribution of charged matter as a sum of rank two tensor electromagnetic potential and energy distribution related to the magnetic moment. may be considered as Electric Displacement energy-momentum tensor describing electric energy transmission.
Now, one obtains the classical picture (charged matter described by
exchanging energy of electric field) being equivalent of the description obtained in QED (leptons exchanging bosons), where tensor
from (
41) may be farther modeled to describe polarization and magnetization by Jones matrices, vectors [
26] and symmetry groups [
27], analogously as it is done in QED.
In QED picture if one substitutes (
A27) for the current Lagrangian density employed in QED
one simplifies currently used
and may derive equations that characterize the entire system involving the electromagnetic field where leptons (described by spinors) exchange bosons. However, such a representation of matter can be treated as an equivalent of
where the description used, reveals only the density of the electromagnetic four-force (
38) and four-current (
A28).
From this perspective, these equations describe all the forces in the system. As was shown in previous section, four-force densities
and
naturally emerge within the system, and the resultant Lagrangian density duly incorporates this aspect. These forces are now invisible in the equations, because they have been "absorbed" by the used description of charged matter
, explained in (
41) and (
38). Above interpretation may thus clarify the challenging quest for identifying quantum gravity as a distinct interaction within Quantum Field Theory. It would also explain the remarkable precision of QED’s predictions, provided it indeed characterizes the complete system involving the electromagnetic field.
Since in the system under consideration, all the energy present is the result of the existence of the electromagnetic field (including the energy of charged particles), the above reasoning also leads to the possibility of interpreting the Poynting four-vector
in (
34)
In the above, the first term is responsible for transferring the energy of magnetic moment what just describes the movement of the density of charged matter. The second element (related to Electric Displacement energy-momentum tensor) can be associated with the transfer of the electric field energy carried by light. From (
A27)
what using (
31) leads to the conclusion that
since the energy and momentum densities of photons should be equal.
This conclusion opens the way to quantum analyzes and makes it possible to provide an equivalent of the presented interpretation for point-like particles.
2.3. Classical And Quantum Interpretation For Point-Like Particles In Flat Spacetime
According to interpretation from previous section (
44), canonical four-momentum
as the volume-integrated
(
A32) in the description for point-like particles may be associated with a photon, thus
what yields
. This confirms the possibility of analyzing light as energy quanta and preserves the fundamental property of equality of energy and momentum of the photon. From (
A37) one may also notice, that for a complete description of the behavior of a particle in flat spacetime with an electromagnetic field, it is enough to know Lagrangian and the four-vector
associated with a certain rotation or spin. Unfortunately,
is unknown, but a quantum solution can be proposed that will shed new light on the interpretation of Quantum Mechanics.
At first, one may propose general method for quantum analysis. Referring to conclusions (
A24) and (
A37), one may introduce new four-vector
using volume magnetic susceptibility
from (
3) as follows
what yields
Since generalized canonical four-momentum
is four-gradient on Hamilton’s principal function (
A34), therefore, according to freedom of gauge rules, in above equation, four-vector
is just other gauge of
. Also for any other scalar
, four-vectors
and
always will be an electromagnetic four-potential.
One may thus introduce quantum wave function
and wave four-vector
related to canonical four-momentum in its simplest form equal to
Then, acording to (
8) and (
A24), one may rewrite (
47) as just
The above equation can be tested in many different quantum applications, which will allow to definitively confirm or deny the validity of the approach proposed in the Alena Tensor theory.
One may now perform reasoning that will show, that presently used quantum equations may be considered as approximation of the above equation. Using freedom of gauge rules and conclusions (
A37) and (
A39), one may introduce electromagnetic four-potential
defined in following way
what yields
and thanks to property
from simple calculations one gets
Introducing electric energy
and magnetic energy
associated with particle as the volume integrals of the energy densities
from equation (
30), according to (
7), (
29) and (
31) one also gets
thus
Therefore by introducing vector
such that
one may rewrite (
52) as
what also shows, that with constant H also
value is constant. Now, one may perceive the particle using the newly created quantum wave function
, e.g.,
to get Klein-Gordon formulation
One may also consider particle by the corresponding Dirac equation derived in a classical way from above. It would lead to conclusion that the description of a free particle may be considered as contraction of electromagnetic four-potentials with the use of spinor representation.
Finally, it can be shown that the above leads to obtaining the equivalent of the Schrödinger equation. At first, referring to the expression for Lorentz factor
introduced in (
15) one may notice, that
Using the above property, a more complex scalar
can be defined as
which after a moment of calculations gives
Next, it maybe seen from (
A36) and (
A37) that
Therefore, referring to (
53), (
54) and using freedom of gauge rules, a following electromagnetic four-potential
can be created
and (
62) yields, that second electromagnetic four-potential
is
Now using above and (
48) one obtains
what allows to recreate Schrödinger equation by taking zero-components of above four-vectors
where
may be approximated as 2m with high accuracy up to velocity
.
The reasoning presented in this chapter ensures high compliance with the results of Quantum Mechanics and indicates, that the currently used quantum equations for the system with only electromagnetic field may be considered as approximation of the results obtained with the use of Alena Tensor. What is also important, the quantum equations discussed above describe the entire physical system under consideration, including the electromagnetic force, gravity and the Abraham-Lorentz effect, which agrees with the conclusions from the previous chapter. This also means that the non-commutativity of QM is no longer an obstacle to its unification with GR, with the use of Alena Tensor.
In the interpretation presented, one obtains a picture in which gravity and the Abraham-Lorentz effect, in some sense, have always been present in quantum equations. They can be made visible by expanding equation (
49) using volume magnetic susceptibility
from (
3), to the form
In the classical picture, according to the conclusion (
A42) and (
6), this leads to the existence of all three forces in the system
where in above, the component
agrees with (
5) describing the force related to gravity and the term
in (
67) is responsible for the force related to gravity and the Abraham-Lorentz effect.