[socratus]

Some remark about SRT.
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The formula E=Mc^2 continues to providethe answers to Physics.
1.
Photon is some " form of energy".
2.
Like a " form of energy" it has the rest energy: E=Mc^2.
3.
This photon has a mass.
But in many books it is written:
"...remember that this (photon,s)energy has mass
in accondance with the equation: M=E/c^2
(mass equal to energy divided by speed squared).
It is not correct.
Why?
Because SRT shows that mass and energy are equivalent:
the property called mass is simple concentrated energy.
In other words massof photon is its energy, and its energy
is its mass, and the distinctionis a simple play of words.
So, the mass of photon is: M=Ec^2 (mass equal to its
potential (rest) energy multiplied (not divided)
by speed squared).
So, it seems we are in some " fairy ring":
E=Mc^2 and M= Ec^2.
When the question is:
How does this potential (rest)energy/mass of one photon
become kinetic and active?
Or in another words:
What does the Law of transformation and conservation
energy/mass mean according to one single photon?
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