My name is Cleo and i’m 15. Recently, I’ve been interested in EM waves and their uses. more specifically, how to study their interactions with each other. Such as how visible waves inter thread with another wave frequency like X-Rays.

A new LIGO detection today has a mean distance estimate of 7412 Mpc. Does that mean that this LIGO distance calculation does not account for redshift, since that mean distance estimate translates to an event much older than the age of the universe? Link to event: https://gracedb.ligo.org/superev...

Just wanted to question how Hilbert space dimensions work. From what I've seen, they're used to generalize the mathematics of finite-dimensional Euclidean spaces into infinite-dimensional vectors. I've seen them used in quantum mechanics, and in some cases stated to "inherit finite dimensional sp...

I am calculating power to accelerate an object of mass M in time T. My intuition tells me to calculate kinetic energy of the object and divide by T. Say a mass of 40 kg is accelerated from 0 m/s to 10 m/s in 4 s. That's a kinetic energy of 0.5 * 40 * 10^2 = 2000 J so power required is 2000J/4s = ...

Consider a system described by Hamilton's equations $$\dot{q}_i=\frac{\partial H}{\partial p_i}=\{q_i,H\}, \quad \dot{p}_i=-\frac{\partial H}{\partial q_i}=\{p_i,H\}.\tag{1}$$ I want to prove that a time-independent transformation of the form $$q_i\to Q_i(q,p), \quad p_i\to P_i(q,p)\tag{2}$$ pres...

The QED Lagrangian $$\mathcal{L} =-\frac{1}{4}F_{\alpha\beta}F^{\alpha\beta}+\bar\Psi(i\gamma^\alpha D_\alpha-m)\Psi$$ where $D_\alpha=\partial_\alpha-ieA_\alpha$ is invariant under $$\Psi\to \Psi'(x)=e^{-ie\theta(x)}\Psi, \quad A_\alpha\to A_\alpha+\partial_\alpha\theta(x).$$ Do these transforma...

The life of carbon-14 isotope is about 5 thousand years. But we still are able to detect traces of it in fossils which are older, more than 10 thousand years. Why?

One of the main causes which leads to ill-defined loop integrals in Quantum Field Theory is that the variables of a Field Theory, $\varphi(x)$ for instance, are Quantum Fields which are governed by creation and annihilation operators which fulfill commutation relations which contain distributions...

I don’t understand that why the net charge of the two isolated plates must be zero. If it’s an isolated system then its net charge won’t change, which doesn’t imply its net charge must be zero.