Recent content by the1ceman

  1. T

    Representation of lorentz group

    Woops i made a mistake! d=4^n not d=4n. So that the direct sum method of fundamental reps will not work. Instead i was thinking of this: Is, for example \mathbb{R}^4\otimes\mathbb{R}^4\cong\mathbb{R^{16}} ? Then the tensor product of the fund (or trivial) rep with itself is also a rep of R^16...
  2. T

    Representation of lorentz group

    Ah yes! I will try this thanks.
  3. T

    Representation of lorentz group

    It cannot be this long, because this question is part of question from a past exam paper. Either there is a mistake in the question and the R^d should actually mean \mathbb{R}\otimes\mathbb{R}\otimes\cdots\otimes\mathbb{R} d times(in which case the question is ok) or there are reps of the...
  4. T

    Representation of lorentz group

    Come on ppl someone must know!
  5. T

    Change in Classical Velocity of an Electron

    I assume that the electron is orbiting the nucleus, you can use a certain equation to find the force on the electron, and you know how many protons copper nucleus has. use this to find the velocites.
  6. T

    Solving PDE Problem: du/dt+du/dx=0 with Initial Condition u(x,0)=xe-x2

    One way of solving a pde like that is to always try separation of variables , so that you assumeu(x,t)=X(x)T(t)where X is just a function of x and T just a function of t, plug this into your pde and see what u get!
  7. T

    Another partial differential equation problem

    \frac{\partial\alpha}{\partial x}=1,\frac{\partial\beta}{\partial x}=1 so \[ \frac{\partial u}{\partial x}=\frac{\partial u}{\partial\alpha}\frac{\partial\alpha}{\partial x}+\frac{\partial u}{\partial\beta}\frac{\partial\beta} {\partial x}=\frac{\partialu}{\partialx}=\frac{\partial...
  8. T

    Fourier transform missing 2pi?

    Sometimes the 2pi is written on the outside like you did or sometimes it is incorporated into the exponential as e^{-2i\pi sx} (substitution in the integrand then gets you from the 2pi in the expo to the outside). Make sure that it is of the same form in your book.
  9. T

    Representation of lorentz group

    Homework Statement i) Show that the Lorentz group has representations on any space \mathbb{R}^d for any d = 4n with n = 0, 1, 2, . . .. Show that those with n > 1 are not irreducible. (Hint: here it might be useful to work with tensors in index notation and to think of symmetry...
  10. T

    How Do You Quantize the Hamiltonian for a Particle on a Unit Circle?

    Homework Statement The Lagrangian of a non-relativistic particle propagating on a unit circle is L=\frac{1}{2}\dot{\phi}^{2} where ϕ is an angle 0 ≤ ϕ < 2π. (i) Give the Hamiltonian of the theory, and the Poisson brackets of the ca- nonical variables. Quantize the theory by promoting...
  11. T

    What are some recommended resources for studying quantum liquids?

    Yes i have decided to take your advice on board and instead focus more heavily on the mathematical framework needed to develope a quantum theory for matter. Perhaps I can then do a short chapter on quantum liquids, that way i can still learn and apply some condensed matter physics. But i still...
  12. T

    What are some recommended resources for studying quantum liquids?

    Thank you very much for the advice. Indeed it could be a very big problem if i start then halfway something goes wrong. That is why i want to start early, within a month i want to finish the introduction. March is the deadline for choosing the project for us, even if something goes wrong i...
Back
Top