# Quantum Physics

- Mathematical description of the motion and interaction of subatomic particles. Quantum Mechanics & Field Theory
 Meta Thread / Thread Starter Last Post Replies Views Pinned: Quantum Physics Forum Rules Before posting anything, please review the Physics Forums Global Guidelines. If you are seeking help with a... Feb23-13 08:38 AM ZapperZ 1 30,452 Hi guys, is there a reason why the energy of the harmonic oscillator is always written as:$$E_{n} = \hbar \omega... Apr19-13 02:38 PM dextercioby 1 435 Hey, I consider a diagonalized Hamiltonian: H=\sum\limits_{k} \underbrace{ (\epsilon_{k} u_{k}^2 -\epsilon_{k}... Jan8-14 09:20 AM DrDu 1 384 Hello, I regard field-operators, whereby \Psi is a fermionic-annihilation-operator and \vec{A(\vec{r})} is an... Jan17-14 05:47 PM Avodyne 2 295 Hello, I am thinking for some hours about the commutation of the field-Operator/(annihilation-Operator): \Psi and... Jan18-14 11:30 PM Avodyne 3 350 Hey, in my notes I have calculated the Eigenenergie of the Hamiltonian: H= \hbar \omega (n+\frac{1}{2}) \cdot ... Jan28-14 04:13 PM Cthugha 4 356 In my note, we have written the field strength tensor as: F^{\mu\nu} =\partial ^\mu A^\nu -\partial ^\nu A^\mu... Jan28-14 07:10 PM ChrisVer 5 308 Hi I regard,$$=0$$but \Psi is a field-operator. I don't understand why the commutation of the derrivative of... Feb1-14 06:00 PM WannabeNewton 3 309 Hey Guys, I regard two operators \Psi , \Phi , that don't commute. Does the product-rule, looks like that? ... Feb6-14 05:34 AM Bill_K 2 250 Hey guys, I regard a relativistic vector:$$ k^\mu =(k^0,k^1,k^2,k^3,)=(\frac{\omega_k}{c}, \vec{k} )  ... Feb8-14 02:24 PM Meir Achuz 2 263 Hi all. Here is an n-particle hamltonian. H=\int... Jun25-11 10:30 PM strangerep 9 991 Hi everyone, I have a question concerning the double slit experiment that I would like clarified. According to a... Sep28-09 08:05 PM abomination5 1 588 Hi Iam having a little problem understaning why some atoms are configured in a certain way. I know that each... Apr3-10 10:03 PM abotiz 3 985 Hi, There is this one thing that bugs me about photoelectric effect, everywhere I read it says usually the K-shell... Aug31-13 12:03 PM abotiz 10 898 Hi, Iam having trouble understanding (or actually picturing) things I have learned, now that I look back at it. ... Aug29-13 03:22 PM Nugatory 4 448 Suppose, i want to diagonalize operator A by matrix S (A'= S^\\dagger A S). Do i need to form S from "NORMALIZED"... Sep20-10 10:50 PM Parlyne 1 744 Hi, I'm doing research to chipproduction, and I can't seem to figure out how transistors really work (in detail).... May4-05 11:08 AM abraxas 6 2,877 This question appeared in my exam . Q. A bullet of mass 41g travels at 960m/s. what wavelength can we associate... Mar20-11 03:06 AM abrowaqas 2 1,184 Hey guys! First time posting on this site. Been reading for quite a while and really loving it! :thumbs:! I'm a... Feb12-14 01:09 AM Khashishi 3 365 Hi guys. I'm trying to get the idea of probability density for 1s hydrogen atom. I just don't understand that... Feb22-14 10:51 AM jtbell 3 344 Hey guys. I'm struggling to picture ultraviolet catastrophe. The graph tells me that at certain temperature, intensity... Apr11-14 05:46 PM The_Duck 3 429 Hi, I am scratching the surface of information regarding particle physics. I have a basic understanding of standard... Aug9-12 03:01 PM JeremyEbert 19 4,143 I've been looking into the time independent schrodinger equation (E\Psi = Ĥ\Psi.) I know that \Psi is the wave... Jul9-12 07:10 PM nonequilibrium 1 737 Hi, ΔEΔt ≥\frac{h}{4\pi} How does this formula relate to particle creation? I understand that it is relevant to... Feb1-13 11:58 AM The_Duck 2 411 Is Gravity a Force of Attraction? We are familiar with electromagnetic attraction and we understand how and why it... Dec18-04 05:18 PM selfAdjoint 1 3,928 In The L=0 states in Hydrogen atom, the electron has a maximum probablity to exist at r=0 ( at the location of the... May5-06 06:58 AM koantum 7 1,573 Hello How can a monochromatic light induce a transition ( absorption ) between two energy levels whose energy... Jun26-06 08:11 AM inha 3 1,659 Hello I was thinkng of this question and I found it best expressed in a clear manner in another site. I quote the... Oct15-06 10:40 AM actionintegral 37 5,203 I have several questions in quantum optics or the quantum theory of radiaition. I begin by the following three... Nov3-06 03:58 PM actionintegral 4 2,667 Hi, The energy of the quantum mechanical harmonic oscillator is proved to be quantized after solving the... Mar19-07 04:37 PM StatMechGuy 2 1,840 In the famed "quantum eraser" of physics, there is two distinct types, one type which uses an absorptive apparatus for... Mar11-14 10:16 AM Cthugha 5 448 Well I'm trying to understand the double-slit experiment (and quantum mechanics), so could you tell me if this is... May1-12 05:27 PM ace frehley 2 761 There are few questions on an assignment (taken from an old exam, YIKES!) that are confounding me and I was wondering... Apr10-13 07:31 PM ace1719 0 492 I've found many articles online that explain how to solve the Schrodinger equation for a potential dependent on x, but... Apr15-13 07:29 AM DrDu 4 788 (disregard my improvised science lingo) so like... a radio wave has a rather macroscopic wavelength. the photon is... Mar16-14 03:17 AM jtbell 3 273 Hi- I'm trying to calculate the effect of a magnetic field on some spectral lines. I know that each energy... Sep14-11 06:38 PM Acetylene5 1 1,284 Hi! If two particles are entangled, A and B, and someone messes with A, have scientists determined the speed at which... Aug7-05 11:00 AM DrChinese 2 938 Hi! This may be a stupid question, but here goes. Is it possible to do a measurement to determine if a photon's... May18-08 02:14 PM peter0302 1 1,211 why is there an upper limit to the photon energy that can be observed in the emission spectrum of the hydrogen atom? Aug8-10 06:59 PM Eudoxie 2 3,048 The problem statement, all variables and given/known data Debye considered atoms to oscillate from 0 up to a nu... Apr10-11 09:44 PM acherentia 3 2,262 Hello everybody, I was revising for my quantum mechanics course and I was wondering why when we approximate the bond... Feb25-12 09:13 AM achilleasatha 0 620