Recent content by alex3

Apologies, I had trouble fitting the question into the format. I shall try harder next time :) Do you mean I should plot \operatorname{d}\sigma/\operatorname{d} p_T against p_T? I know I need to do that, my problem is trying to find the differential values. i.e. How could I figure out "the...

I have a differential that depends only on \cos{\theta} \frac{\operatorname{d}\sigma}{\operatorname{d} \Omega} = f(\cos{\theta}) I am numerically solving this differential equation for \sigma, which physically is a cross section, for 0 \leq \theta \leq \pi. The differential contains a...

Got it now, thank you very much!

Why do we assume g_{\alpha\beta} is symmetric then? Is that a property we assume of all metrics? I didn't think we did. Do we assume symmetry of g_{\alpha\beta} as it deviates only slightly from the Minkowski metric?

How do we know that h_{\alpha\beta} is symmetric? I can't see it mentioned anywhere. The only condition I see is \lvert h_{\alpha\beta}\rvert \ll 1.

I'm reading a few textbooks (Straumann, Schutz, Hartle) on GR and am a little confused working through a small part of each on linearized GR. 1. Relevant equations Using Straumann, the Ricci tensor is given by R_{\mu\nu} = \partial_{\lambda} \Gamma^{\lambda}_{\phantom{k}\nu\mu} -...

Of course! Thank you, it's very clear now.

For the following two-dimensional metric ds^2 = a^2(d\theta^2 + \sin^2{\theta}d\phi^2) using the Euler-Lagrange equations reveal the following equations of motion \ddot{\phi} + 2\frac{\cos{\theta}}{\sin{\theta}}\dot{\theta}\dot{\phi} = 0 \ddot{\theta} -...

I'm numerically evaluating the differential cross sections \frac{\operatorname{d}\sigma}{\operatorname{d} \Omega} for e^{-}e^{+}\rightarrow\mu^{-}\mu^{+} scattering by integrating over \operatorname{d}\Omega = \operatorname{d}(\cos{\vartheta})\operatorname{d} \phi. Assuming no transverse...

Solution: F_{1} = -k_{1}x_{1} - k_{2}x_{1} + k_{2}x_{2} F_{2} = -k_{3}x_{2} + k_{2}x_{1} - k_{2}x_{2} Thanks all the same!

Homework Statement Two masses attached via springs (see picture attachment). k_n represents the spring constant of the n^{th} spring, x_n represents the displacement from the natural length of the spring. There are two masses, m_1 and m_2.2. The attempt at a solution My problem is formulating...

For the second question, consider every force acting on the block: it has just reached the top of its ascent, so it will have gravity acting on it. The frictional force will always be opposing the direction of motion, so will be *up* the slope, so you require that the frictional force is greater...

Negative g is correct, but it will yield a = -(g\sin{\theta} + \mu g \cos{\theta}) This is because you're original assumption of making the frictional force negative (against the initial velocity) was correct, but it was correct because you treat g as negative. Then, the gravitational force is...

You've put the frictional force with a negative sign, implying it's going down the slope (i.e. against the initial direction of motion), so what about the gravitational force, what sign should that have?

Looks great, nice work!