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What are prerequisite courses/topics to better understand holography as applied to strongly correlated condensed matter systems? Any references/textbooks would be appreciated. I'm doing research on this topic and would like my understanding to improve. Thanks very much

I'm not sure. I have only submitted one problem and I haven't been given it yet. I've participated in about 8 competitions, most of them with myself since the site is still small.

I found a really cool website where you can have physics problem solving competitions with others. It's brand new and it's called PhyKings: www.phykings.com. You can start a competition, pick the number of players, the length of the problem, the type of problem, and once everyone joins, you...

I am an undergraduate who recently started on a research project involving the dielectric properties of colloidal suspensions. Though my physics background is strong, my chemistry background is weak and I would like to learn about the following concepts relevant to my research: 1. Electrode...

10 out of 12

You should try the integral and find out for yourself!

Try this one $$\int_{0}^{\pi/2}{ dx \over {1+\tan^{2015}{x}}}$$

The results in that paper seem quite impressive. But what is the future of such simulations? Could they be used to map trajectories that are common to all proteins in phase space (the energy landscape)?

Nice! You should try some of the problems in Trivium. There some similar themed problems.

Check out this collection of mathematics problems, published in 1991, by V.I. Arnol'd called "A Mathematical Trivium". Here's the link: http://www.math.upenn.edu/Arnold/Arnold-Trivium-1991.pdf [Broken] Apparently, these problems are meant to be solvable by the end of your undergraduate (math)...

I know what's wrong with my alternative solution. The component of the normal force that opposes ##2T## is a sum of small normal forces acting in the direction opposite to ##2T##, which act on each element of the rope perpendicular to the surface of the cone. The force that opposes ##2T## can be...

Homework Statement A rope of mass ##m## forming a circle is placed over a smooth round cone with half angle ##\theta##. Find the tension in the rope. Homework Equations ##\sum{F}=0## The Attempt at a Solution I know how to solve the problem, but I have another way that I think should work but...

I think you've made an error in your calculation. If we plug in ##\ell = 1## and ##m=1##, we have $$P^{1}_{1}={(-1)^1 \over 2 \cdot 1!} (1-x^2)^{1/2} \cdot {d^2 \over dx^2}(x^2-1)$$ Do you have that much? It should be easy to simplify that, then plug in ## x=\cos{\theta}##.

We won't do the calculation for you. Why can't you do it yourself? What part of it doesn't make sense to you?

You posted this in the wrong forum. There is a forum for textbook discussion at the top of the forum list. From my experience, there aren't very many great thermo/stat mech books at the undergrad level. But I've heard Fundamentals of Statistical and Thermal Physics by Reif is a good text. I...

That relation holds only if ##\left( \frac{D-1}{2} \right) \left( \frac{D-3}{2} \right) \frac{1}{r^2} \psi = 0##.

Thanks for the recommendations. I've looked into the Schaum's books. They are helpful but the problems are not very challenging, particularly in the Digital Principles version. Unfortunately, we aren't allowed to bring books into our exams... Any other recommendations are gladly welcome!

Not if the force is infinite (or very very large), which is usually the case for collisions.

Can you use separation of variables?

I think QuantumCurt got it right. He/she said quantization of charge is necessary for magnetic monopoles, not that it is sufficient.

Check out "Solid State Physics Problems and Solutions" by Mihaly & Martin.

Why can't there be an impulse if the collision is instantaneous? EDIT: I might not have been clear on this: the impulse is in the ##- \hat{i}## direction.

When the mass hits the rod, there is an impulse from the pivot on the top of the rod. This impulse is not known, so you are better off using the conservation of angular momentum about the pivot (as they did in their solution). That way, the impulse force has no torque.

Do you mean to show that ##\neg (P \leftrightarrow Q) \equiv (P \leftrightarrow \neg Q)##? Why not just use a truth table?

Principles of Quantum Mechanics by Shankar seems to be highly rated. However, I haven't read it yet so I can't give a personal review

The first Brillouin zone is a primitive cell of the Fourier transform of the lattice. It is found in the same way that you find a primitive cell of a lattice, using the Wigner-Seitz procedure.

That's the approach I've been taking recently. However, I have yet decided whether or not it's the best approach yet. To be honest, I just enjoy working problems more than I enjoy reading the textbook passages.

Why don't you just go ahead and start studying calculus? If you are as solid at algebra, geometry, and trig as you claim to be, then you should be ready.

Obviously, it is important to work lots of problems when learning math and physics. At the same time, it's useless if you haven't learned the material from reading the textbook sections. I can see two extreme approaches to studying out of a textbook. The first is reading the textbook extremely...

If you calculate the motion of an electric charge ##q## in a field produced by a magnetic monopole, an angular momentum term arises that is proportional to ##q##. Since quantum mechanics says that angular momentum is quantized, this means that ##q## must also be quantized. So if only one...

I think Mathematical Methods for Physicists by Arfken & Weber might suit your needs, but why don't you just see what the textbook for the course is?

Yep, it's about as simple as that.

Both of these are incorrect. If the sphere is uniformly charged, then ##\rho## is constant, i.e. independent of ##r## right? The potential is ## \phi(\vec r)=\frac{q(r)}{r}## where ##q(r)## is the charge of a uniformly charged sphere of radius ##r##. ##q(r) \neq e##!

That's right. Remember to integrate over ##\theta## and ##\phi## as well.

The remaining boundary conditions in the problem will give you something useful. Namely, you have the potential on the inner surface of the cylinder -- use it.

I think that you have the right idea, but this formula is wrong. You should be able to see that the units are wrong. Recall that ##dq=\rho dV## where ##dV## is a differential volume element. So you need to find ##dV## for a thin spherical shell.

You need to attempt the problem before we will help.

Thanks very much for the responses! What makes them so sure that the structure of protein will be completely determined by its amino acid sequence?

It looks like you are approaching this problem in a very difficult, brute force way. Suppose you have a uniformly charge sphere of radius ##r##. What is the energy required to add a thin, uniformly charge spherical shell of thickness ##dr## to it? See if you can use the answer to this question...

You should review calculus first if you're rusty. Then grab an intro physics text like Halliday & Resnick.

Try multiplying both sides by ##r^2##.

Thanks very much for the recommendations! The book by Mihaly & Martin looks good!

As a non-biologist, I'm curious: What are some things that current research on protein folding is focusing on? What are some current challenges that researchers are facing? I understand that the protein folding problem is a very important problem in the field of biophysics. Any experts on here?

An exercise book for the Feynman Lectures was recently released. The problems there are quite good. I'd say Feynman lectures are the must-read books for general physics. After you become more advanced, take a look at the Landau & Lifshitz volumes. Other than that, it depends on the topic you...

Yeah, it would be pretty scary to see that integral on a physics test.

Was that for a test? If so, that's a bit strange to not provide an integral table. You might do well to review integration material in a single variable calculus, I don't think math methods books will cover integration at that level. Websites like Brilliant.org have good calculus exercises, so...

What are some recommended resources with good problems (and preferably solutions as well) on Solid State Physics at the level of Kittel? I'm aware of Yung-Kuo Lim's "Problems and Solutions on Solid State Physics, Relativity and Miscellaneous Topics" which has graduate qualifying exam questions...

Also, if your school has a good library, you can probably find them there.

Any math methods book (ex. the one by Mary Boas) will probably cover integrals needed for physics courses. I'm curious, do you remember what the integrals were?