photon有沒有重量？

One point that you need to note is that a photon has no "rest mass". If it had, it would not be able to travel at the speed of light according to the Special Theory of Relativity.

In the equation m = E/c^2, you could treat such calculated result of "m" as the "mass" of a photon. But this is only a mathematical calculation result, it has no physical significance at all.

Strictly speaking, the classical definition of momentum, mass x velocity, may not be applicable in the quantum world. The derivation of the equation p = E/c using the classical approach that I gave is just an "illustration", it cannot be regarded as a formal proof. This is similar to the case that Bohr's model of the hydrogen atom can be proved using a classical approach with principles in electrostatics and circular motion. But the formal proof requires the use of Schrodinger's equation in quantum mechanics.

All in all, it is commonly accepted that a photon has energy and momentum but no mass. More specifically, you can only write down the momentum of a photon
as E/c, but not mc.

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光子的靜止質量是零,因為如果有靜止質量,那會違反了相對論.


在移動中的光子質量不能用數學來計算,必定要做實驗才有確實答案.
(暫時不可能)


也有這條方程:
.............____________
Mo=M/√ 1-[(v^2)/(c^2)

待續,不夠位.

2011-12-02 11:29:38 補充：
當你代零入V(速度)時,你會得到Mo=M/√ 1

Mo=M Mo=光子靜止質量
M =移動中的光子質量



所以光子靜止質量是等於移動中的光子質量

2011-12-02 11:32:58 補充：
上面的很亂,重寫


Mo=M

Mo=光子靜止質量
M =移動中的光子質量


所以光子靜止質量是等於移動中的光子質量