ndrearu
• Member for 3 years, 11 months
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There are many textbooks or reviews representing a good introduction to Lattice QFTs. Here I list some of them I found very useful in my studies (sure I'm missing something). Lattice Gauge Theories ...

Ok let's try. I think that there are a lot of way to do so and I will try one (maybe not the faster way, but should be clean enough). To understand the motion we need just two dimensions, so we work ...

The mistake is just here If we use θ, ϕ and ξ to describe the position of P, it means P has three degree of freedom. The number of degrees of freedom is not the number of variables you use to ...

Generally speaking, in a Markov Chain Monte-Carlo (MCMC) the therm step may be used to indicate any move from a state (or configuration) in the chain to the next one. Clearly, this step (or update, ...

Obviously is not the dimensional analysis to be wrong. It is wrong if one tries to rely only on it to find physical laws, despite it clearly represents a very good help to us. In the example of the ...

No, the $E_i$s are energies. In statistical mechanics it can be show (see for example here) that the Helmotz's free energy $F$ is related to the partition function of the system in the following way ... View answer 2 votes Yep, it is actually just a matter of convention. I don't think that choosing the first or the second one would change nothing but the convenience in the computations. As far as I know, the second ... View answer 2 votes Be careful. Heat refers to the transfer of energy between thermodynamical systems, and so it is not properly correct to say that a system has heat. A system has energy which can be transferred in form ... View answer Accepted answer 2 votes The Carnot theorem states the maximum efficiency of an heat engine is that of the Carnot heat engine and this depends only on the temperatures of the two heat reservoirs. In addition to that, there is ... View answer 1 votes I would try to go through the questions: The definition of thermal equilibrium is quite more general. According to K. Huang (K. Huang, Statistical Mechanics) Thermodynamic equilibrium prevails ... View answer Accepted answer 1 votes I think that a possible and very simple argument may be just the following. The heat capacity is the quantity of heat needed to vary the temperature of a certain amount. If it grows with the ... View answer 1 votes Ok your ansatz about the form of the \psi. Now, the other conditions you need come from the discontinuity of the derivative through the delta potential. If you take the time-independent Schrödinger ... View answer 1 votes A way to answer is just to write down the equation of motion and let you see that mass is not involved. However, I think that your question may lie on a more deep level. It seems stupid but, perhaps, ... View answer 1 votes You're just missing that there is something proportional to e also in the four-potential A_\mu since A_\mu=(\phi,\vec{A}) where \phi and \vec{A} are the scalar and vector potentials. The ... View answer 1 votes It is not necessary to add c, it is just useful in order to check quickly the dimensions, easily recognize quantities and get the numerical value of the formula faster. This is done often in Physics ... View answer 1 votes It should be just a problem of definitions of the mediums and their refractive indices. In the general case, when you have two mediums separated by a boundary and with refractive indices n_1 and ... View answer Accepted answer 1 votes Magnets tends to align to the field lines of a magnetic field. Earth possesses a magnetic field whose axis does not coincide with the rotation one but differs of about 11° (see here), so in ideal ... View answer 1 votes A way to show that a single photon cannot decay into a massive particle-antiparticle pair can be wrote down by using the four-vector formalism. The decay is k^\alpha=p_1^\alpha+p_2^\alpha $$where ... View answer 0 votes The second formula must be handle with care. It is possible to show that the thermodynamic partition function of a system described by an Hamiltonian H may correspond to the path integral under some ... View answer 0 votes Yes, indeed it is the expression of the energy of a relativistic massive charged particle in the presence of an electric potential. Consistently, if the expression is expanded in the limit cp\ll mc^2... View answer 0 votes If I understand correctly, you want to find \delta v=v(t_2)-v(t_1), the difference between the velocities of a point at some instants t_2>t_1, knowing the value of the accelerations a(t_2) ... View answer Accepted answer 0 votes You're right when you say that [...] velocity will be partially due to linear motion of the whole system, and partially due to rotation of A around B. indeed, the velocity of A is the sum of two ... View answer 0 votes Here a little trick: if you write$$ \mathbf{F}' = \frac{d\mathbf{p'}}{dt'} = \frac{d\mathbf{p'}}{dt}{\Big/}\frac{dt'}{dt} $$then$$ F'_x=\frac{dp_x'}{dt}{\Big/}\frac{dt'}{dt}\quad F'_x=\frac{dp_y}{...

The argument is that in Galilean transformation you assume time to be absolute. Translating this requirement in an operative statement, you want intervals of time between to events to be invariant ...

If I understand correctly the answer, it is just a matter of understanding who-is-who. Stating that a function is periodic with period $2\pi$ means that if its argument is shifted by $2\pi$, than the ...