Minkowski Force due to a quadratic in velocity potential

QFT25
Messages
24
Reaction score
3

Homework Statement


A generalized potential suitable for use in a covariant Lagrangian for a single particle. This is Goldstein problem 9 chapter 7.

−Aλν(xμ)uλuν

where Aλν stands for a symmetric world tensor of the second rank and u^v are the components of the world velocity. If the Lagrangian is made up of (1/2)m*u_v*u^v minus U, obtain the Lagrange equations of motion. What is the Minkowski force? Give the components of the force as observed in some Lorentz frame.

Homework Equations



Euler equation of motion where the derivatives are taken with respect to the four velocity and where and the time part if the proper time. Also that the four force is the mass times the four velocity.

The Attempt at a Solution



When I workout the Lagrangian I have an extra term which is proportional to the four acceleration. My first thought is to solve for the four acceleration and then multiply it by the mass to get the Minkowski force. Is that valid? [/B]
 
Minkowski 4-Force = dP/d-tau where P is 4-momentum;
or 4-Force = gamma(3-Force, id/dt(mc)) where m is relativistic mass.
 
Thread 'Need help understanding this figure on energy levels'
This figure is from "Introduction to Quantum Mechanics" by Griffiths (3rd edition). It is available to download. It is from page 142. I am hoping the usual people on this site will give me a hand understanding what is going on in the figure. After the equation (4.50) it says "It is customary to introduce the principal quantum number, ##n##, which simply orders the allowed energies, starting with 1 for the ground state. (see the figure)" I still don't understand the figure :( Here is...
Thread 'Understanding how to "tack on" the time wiggle factor'
The last problem I posted on QM made it into advanced homework help, that is why I am putting it here. I am sorry for any hassle imposed on the moderators by myself. Part (a) is quite easy. We get $$\sigma_1 = 2\lambda, \mathbf{v}_1 = \begin{pmatrix} 0 \\ 0 \\ 1 \end{pmatrix} \sigma_2 = \lambda, \mathbf{v}_2 = \begin{pmatrix} 1/\sqrt{2} \\ 1/\sqrt{2} \\ 0 \end{pmatrix} \sigma_3 = -\lambda, \mathbf{v}_3 = \begin{pmatrix} 1/\sqrt{2} \\ -1/\sqrt{2} \\ 0 \end{pmatrix} $$ There are two ways...
Back
Top