Photons rest mass

Possible Methods for Determination of the Photon Rest Mass The Photon as a Particle with an Associated Wave The Electric Charge, Angular Momentum, and Longitudinal Field The Photon Radius... 

It should finally be mentioned that the basic equations (l)-(8) have been derived from gauge theory in the vacuum, using the concept of covariant derivative and Feynman s universal influence [38]. These equations and the Proca field equations are shown to be interrelated to the well-known de Broglie theorem, in which the photon rest mass m can be interpreted as nonzero and be related to a frequency v = moc2/h. A gauge-invariant Proca equation is suggested by this analysis and relations (l)-(8). It is also consistent with the earlier conclusion that gauge invariance does not require the photon rest mass to be zero [20,38]. 

The effects of the nonzero electric conductivity were further investigated by Roy et al. [20,50-52]. They have shown that the introduction of a nonzero conductivity yields a dispersion relation that results in phase and group velocities depending on a corresponding nonzero photon rest mass, due to a tired-light effect. 

The question of the possible existence of a nonzero photon rest mass was raised by Einstein [42], Bass and Schrodinger [43], de Broglie and Vigier [44], and further by Evans and Vigier [5], among others. It includes such crucial points as the relation to the Michelson-Morley experiment, and the so far undetermined value of such a mass and its experimental determination. 

Consequently, there should be no noticeable departure in recorded velocity from the Michelson-Morley experiments when the photon rest mass is changed from zero to about 10-39 kg = 10 9me or less. For a photon rest mass in the range... 

In all approaches with a nonzero photon rest mass the velocity c should be considered as an asymptotic limit at infinite energy that can never be fully approached in physical reality by a single photon in vacuo. 

Thus, the uncertainty in the absolute value of the nonzero photon rest mass does not necessarily imply that the corresponding theory is questionable, but rather could be due simply to some so far hidden extra condition or refinement that may have to be added at a later stage to obtain such a value. 

Possible Methods for Determination of the Photon Rest Mass... 

For the determination of the photon rest mass, the following considerations can be of importance ... 

Anisotropic effects of the recorded frequency of cosmic microwave background radiation have been proposed for photon rest mass determination [20]. 

In Section V, the photon was described as an electron-positron pair in rotation in E. In the 4D ether, antiparticles are dynamic sinks, so that an electron-positron pair has a zero net momentum flux, thus explaining the photon rest mass. The photon is then a composite charge-neutral and mass-neutral entity. 

Use has been made of the relationship = P c (the photon rest mass is zero). Equation 3.34 gives the kinetic energy of the nucleus after the emission of a photon of energy E. This energy is called the recoil energy. 

Although the photon has zero rest mass and spin 1 and thus does not follow the Dirac equation [5], Table 2.2 also gives a computed rest mass for a photon tfavelling freely across the universe, assuming for the latter a radius of 13.7xl0 light years. If the universe were flat and infinite, the photon rest mass would be zero. The value given here is purely formal, not only because it is very small but also because it could be detected only by an observer external to our universe ... 

The photon rest mass is zero therefore, their velocity is always equal to the velocity of light. That is, photons cannot be slowed down in matter (unlike charged particles). Photons can be only scattered or absorbed. 

The possibility of small deviations from Coulomb s law has been considered. Experiments have shown that if the Coulomb s-law force is written as being proportional to then s < 10 . It can be shown that a deviation from Coulomb s law would imply a nonzero rest mass for the photon see A. S. Goldhaber and M. M. Nieto, Rev. Mod. Phys., 43,277 (1971). There is little or no evidence for a nonzero photon rest mass, and data indicate that any such mass must be less than 10" g L. Davis et al., Phys. Rev. Lett., 35,1402 (1975) R. Lakes, Phys. Rev. Lett., 80,1826 (1998). 

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