*Reference: **A Logical Approach to Theoretical Physics*

I asked this question on Quora: **If photon is massless, how is mass defined in physics?** Most answers that I got were cookie cutter answers from quantum mechanics perspective that do not see the following inconsistencies:

(1) The concept of particle comes from matter. A material particle is discrete because it can be treated mathematically as a point particle as it has a center of mass. The concept of particle ends when there is no center of mass.

(2) Electrons have mass, but no center of mass. In the absence of center of mass a particle cannot be distinguished from another particle. There is still mass but no discreteness. Electrons are, therefore, a fluid-like continuum rather than discrete particle-like collection. This logic is ignored by quantum mechanics.

(3) Energy interactions are always discrete because it takes a precise amount of energy for a unique interaction to take place. But a discrete energy interaction does not imply that the interacting elements are discrete in space also. Einstein’s “energy particle” is a discrete energy interaction. It was an error to assume that a discrete “energy particle” is also a discrete “mass particle” in space.

Electrons and light are fluid-like continuum per the above logic, but they can have discrete energy interactions. That is perfectly okay. Electrons and light are fluid like continuum is confirmed by the mathematics of Quantum Electrodynamic, as shown by Richard Feynman in his lecture on quantum behavior. Please see **Feynman on Quantum Behavior**.

What is missed by quantum mechanics is that mass can be fluid-like continuum that is infinitely divisible. This is what Newton implied in his Corpuscular theory of Light. From **Corpuscular theory of light – Wikipedia**:

*“Corpuscular theories… are similar to the theories of atomism, except that in atomism the atoms were supposed to be indivisible, whereas corpuscles could in principle be divided. Corpuscles are single, infinitesimally small, particles which have shape, size, color, and other physical properties which alter their functions and effects in phenomena in the mechanical and biological sciences.”*

Corpuscles, thus, provide a dimension of fluid-like continuum of “mass concentrations” that can be reduced indefinitely. These concentrations are represented by the frequency of EMR. Frequencies formed the basis of the original concept of quantum.

The idea of “rest mass” may be understood as follows: If we are traveling at the speed of light along side a beam of light, that beam shall appear as a fluid continuum that has the mass concentration of **E/c^2**. Mass is more basic than energy. Kinetic energy is the energy of moving mass.

Light’s speed is intrinsic and finite because of its mass concentration. Please see **The Logic of Motion**.

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## Comments

QUESTION ON QUORA:

Is the secret of the speed of light in the internal structure of the speed of light within quantum physics?Yes. The speed of light is absolute. That means it depends on its intrinsic characteristics and not on the speed of anything external to it.

That internal characteristic is the mass concentration of light as explained here: The Logic of Motion.

Light is a fluid continuum of certain mass concentration as explained above. Therefore, Newton’s corpuscular theory is more applicable to it than the wave theory or quantum mechanics. Except that these corpuscles are not discrete. They form a continuum.

The corpuscles may best be compared to electromagnetic cycles. Each cycle is more like a corpuscle. It is infinitely divisible because a unit of time is infinitely divisible. The higher is the “frequency” of light, the denser are the corpuscles that light is made up of. Therefore, the mass concentration of light increases with its frequency, and the speed of light decreases. But this speed decreases in infinitely small gradients throughout the electromagnetic spectrum.

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