How can I interpret the normal modes of this mechanical system? The equations of motion for the system are as follows: $$\left[\begin{array}{ccc} m_{1}\\ & m_{2}\\ & & 0 \end{array}\right]\left\{ \begin{array}{c} \ddot{u}_{1}\\ \ddot{u}_{2}\\ \ddot{\alpha} \end{array}\right\} +\left[\begin{ar...

I am an electrical engineering by trade, working on the analogue part (Transmitter & Receiver) of a quantum optical communication channel. By this, I mean I have not much experience on things quantum. There are, however, some notions or concepts that I would like to understand, but no matter how ...

To see where QCD starts to differ from the behavior of EM fields, we might begin by looking at the classical field. A search brings up [question 339978] and [question 360061] but no answer is found there. With the usual [QCD Lagrangian] definition: $$\begin{align} \mathcal L_{\text{QCD}} &= \bar\...

I have a physics problem in my book, where a spring is compressed and a ball is laying in the end of the spring. When the spring is released the ball will reach a certain speed. In the solution it says that all the spring potential energy will be converted into the kinetic energy of the ball. Wha...

I would like help in understanding something that has been causing me a lot of trouble recently. Why is energy always related to time in physics. Whether it is in the 4-momentum, the energy-time uncertainty principle, hamiltonian mechanics. And especially how is the hamiltonian the generator of t...