There are few constants that usually come together, $e/m$ also $h/e$. How are they decoupled? If the speed of light is "derived" as Wikipedia states how meter defined and time?
With the advancement of Modern Technology still there is no accuracy of the measured value of $G$ Gravitational Constant, why!?
Why do things like protons and neutrons have specific values. Also speed of light is a speed in which even if you go towards it, the speed does not vary. But why does light have to travel at speed?
What is the proof that the universal constants ($G$, $\hbar$, $\ldots$) are really constant in time and space?
Cavendish measured the gravitation constant $G$, but actually he measured that constant on the Earth. What’s the proof that the value of the gravitation constant if measured on Neptune would remain ...