Fine Structure Constant

Question

今日我個 Professor 話, 美國將會耗資 5億美金去研究 Fine Structure Constant ~ 1/137 究竟係一個 constant 還是會隨著時間而改變.

究竟這樣的巨額研究值唔值得? 若不是 constant 會對現在的理論有幾深的影響?

== 嚴禁轉貼 wikipedia ==

Answer 1

The fine structure constant is a fundamental constant in physics and is thought not to change unviversally, both in space and time.

The constant is invloved in the transition process of electrons to give out photons of certain wavelengths. As the fundamental definition of length and time in nowadays are based on the wavelength and frequency of emitted these photons, these definition of length and time are therefore considered as universal. In other words, a length of 1 metre or a time interval of 1 second will be the same anywhere throughout the universe, at present, in the past or in the future. They will not be changing with time and space.

In case the fine structure constant changes with time and space, this leads to the consequence that the fundamental definition of metre or second are different in space and time. The speed of light will no longer constant, but also changes with space and time. The final consequence will be that the laws of physics we know nowadays may not be the same in the past or may be different in other parts of the universe.