Einstein postulated that light itself was made of discrete packets of energy, later known as photons, building upon Planck's quantum hypothesis.

爱因斯坦基于普朗克的量子假说假设，光本身是由离散的能量包（后来称为光子）组成的。

Albert Einstein demonstrated that light, which had previously been considered an electromagnetic wave, must also act as a particle, localized in packets of energy called photons.

阿尔伯特·爱因斯坦证明，以前被认为是电磁波的光，也必须扮演粒子的角色，被定位在称为光子的能量包中。