_{1}

^{*}

Using in CPT a P and T violations we show that the equation of the positron is exactly the same as the one of the electron, on the condition that both the sign of the charge and the electromagnetic potential are changed. As a consequence the velocities are both in direction to the future and the masses are both positive and, in similar experiences, the behaviours of the two particles are the same. These theoretical results are in quite agreements with the experiments of the LEP.

D. Hestenes has established in [

The form given to is the following

where:

expresses the invariant probability density;

;

corresponds to the Lorentz rotation such that and are the velocity and the invariant probability current;

is the Yvon “angle” [

The vectors, are such that the bivectors or define, multiplied by, the angular momentum of the electron, in spin “up” or “down” respectively.

Let us consider the Dirac equation

and the equivalences [

(in “up”), (in “down”),

.

Denoting, one obtains the Hestenes form of the Dirac equation

in “up”, in “down”

Multiplying Equation (2) on the right by (), we obtain [

in “up”, in “down”, where the bivectors define the infinitesimal rotation of the moving frame, or proper frame of the electron.

This equation is independent with respect to all galilean frame. The dimension of each term is an energy. In this form the velocity v is associated with and gives the equation of the free electron, considered when the potential A is null. So this form appears as the most appropriated among the other invariant forms.

Note: The Clifford algebra associated with an euclidean space is a real associative algebra, generated by and the vectors of, whose elements are identified to the ones of the Grassmann algebra. Furthermore this algebra implies the use of the inner products in denoted, for products of a p-vector by a vector a of which correspond to the operation so-called (by the physicists) “contraction on the indices”. The product () defines the signature of. Its principal properties are:

1) The Clifford product of two elements of is denoted AB and verifies the fundamental relation.

2) All element A of is the sum of terms in the form

,.

3).

4) If p vectors are orthogonal their Clifford product verifies.

We recall the usual presentation of the passage from the equation of the electron to the one of the positron by means of the CPT transforms that we apply to Equation (4).

1) C (Charge) changes into.

2) P (Parity) changes into and so, into,.

3) T (Time reversion) changes into and so in.

Equation (4) becomes, after the change of sign of and v, associated with the C change,

However the T transformation seems to imply that the positrons come from the future, contrarily to experiments in particular in the LEP, and these kinds of transformations are to be imperatively interpreted in a different way.

Note that the changes of sign of and are made to put the terms containing the spin and the velocity in agreement with the change of sign of the term containing the charge.

So one has not to change by P into but, instead, to keep unchanged and to change the sign of the term of the equation containing the spin, and so not to change the spin.

In the same way one has not to change by the T transform v into but, instead, to keep v unchanged and to change the sign of the term of the equation containing v, and so not to change the velocity v.

So the positron velocity may be clearly considered in direction to the future and the strange interpretation of T by Stückelberg and Feymann is to be abandoned.

Equation (5) is changed into

that is

This equation is exactly the same as the equation of the electron, with the condition that, the charge being changed into, one has to change the electromagnetic potential A acting on the electron in acting on the positron:.

In [_{b}), T. Takabayasi avoids the change of v into by the following transform:

3)' The angle is changed into which gives

, v remaining unchanged.

A difference with what precedes is the fact the sign minus is placed directly in front of the term containing the mass and so that T may be removed from CPT to be replaced by the above transform on the “angle”.

About the spin the addition of to the “angle”, which in fact concerns not the vectors of M but the bivectors (see for example [

Note that Takabayasi had assigned the sign minus obtained by his transform to the mass, not to the term containing the mass, and deduced a wrong hypothesis of a negative mass for the positron (that we have unluckily repeated in [

About the behaviour of the positron in the LEP experiments we have sent to Michel Spiro, President of Scientific Board of the LEP, then of the LHC, the following message:

“The form of the positron equation is the same as the electron equation, except that the charge is positive. So one can expect that, in similar experiences, the behaviour of the positron ought to be the same as the one of the electron to the condition that the sign of the electromagnetic potential A is changed.”

We have received the following answer (which does not engage its author on the validity of the above calculations) from Dr. Rolf Landua, Head of Education and Public Outreach (CERN):

“I can confirm that this statement is correct. It has also undergone many experimental tests, e.g. by testing the equality of the magnetic moment of the electron and the positron. This measurement is hitherto the most precise comparison of a physical property of particle and antiparticle.”