Electron Definition and 999 Threads

Hi, I'm having trouble understanding angular moment of the one electron hydrogen atom. Solving Schrodinger equation on a referece system (say S) I get the energy eigenstates. They depend on three quantum numbers, n, l, m \frac{-ħ}{2 m}\nabla^{2} \Psi - \frac{e^{2}}{4 \pi \epsilon r} \Psi =...

This is an elementary question on visualizing the interaction of an electron with the surrounding EM field in QFT. I believe in QFT the electron is viewed as an excitation of the Electron matter field with an associated coupling constant between the electron field and EM field (say q) - q...

If I'm scattering electrons off of an atomic nucleus, can I infer any information about the duration of time the electron was accelerating by looking at the wavelength of the emitted bremsstrahlung radiation? I am wondering if it would be possible to derive a time interval between electron...

I am trying to find the thermal speed of electron at room temperature. kT = (1/2)mv^2 which gives v=√((2kT)/m) but answer says it should be √((kT)/m) Where did that 2 go?

What different between QFT and QED? In QFT electron is field quanta, what is electron in QED?

Hey! Let's say we have an electron and proton colliding head-on. We will have ##|p| \sim E## Where ##p_1=(E_1, \vec{p_1})## &##p_2=(E_2, \vec{p_2})## If we want the available energy. We can calculate ##\sqrt{s} = \sqrt{(p_1 + p_2)^2}## We get $$s= p_1^2 + p_2^2 + 2p_1p_2 = m_e^2 + m_p^2 +...

Homework Statement One way to establish which transitions are forbidden is to compute the expectation value of the electron’s position vector r using wave functions for both the initial and final states in the transition. That is, compute ∫ΨfrΨidτ where τ represents an integral over all space...

I'm reposting this thread with some editing suggested by fresh_42: 1. Homework Statement Calculate the mass, velocity and the de Broglie wavelength of an electron and an alpha particle, given the kinetic energy K = 2MeV Homework EquationsThe Attempt at a Solution please find attached![/B]...

Hi, As far as I understand spin orbit coupling is the interaction between proton of atom and electron. Proton's motion(from the frame of electron) around electron creates magnetic field. Hence electron experiences magnetic field. Does this magnetic field produces a Zeeman effect which cause...

I know that total magnetic moment of an electron (I am not sure if it is magnetic moment of electron or atom, please clarify this) is sum of magnetic moment caused by orbital motion and spin angular momentum. So, Total magnetic moment = Orbital magnetic moment + spin magnetic moment Do I have...

Suppose you have a pair of electrons in the same quantum state, and are thus spin entangled, and they absorb a pair of photons and release them at the same time. How would this affect the photons? Would the photons be entangled? Would it affect the photon spin, and if so, how would it affect the...

Hi all, I am having trouble understanding the some ideas presented in some notes I've been reading, help is greatly appreciated! I've uploaded screenshots of the material I'm referring to below, the last two images are what I'm mainly referencing, and the first few are to provide context...

Previously I posted a problem concerning Electron-neutrino scattering, but as I couldn't describe the problem clearly, so I am trying to post the problem using latex codes to present it in the correct way. For a couple of months, I am trying to calculate the invariant amplitude of the Neutrino...

If the mass of the electron has been changing during the evolution of the universe, then the orbits of the electrons would also change, which will shift the light spectrum of each atom. Could this explain red shift of far galaxies, and the shift is not because the universe is expanding? Henry

For a couple of months, I am trying to calculate the invariant amplitude of the Neutrino electron scattering in the standard model (SM) approach where I am not considering any kind of approximation and using the SM propagator for W Boson and Z Boson. I tried to do as following, find out the...

In Abraham Pais book (which was first published in 1982), he states the following: "Quantum field theory has taught us that particles nevertheless have structure, arising from quantum fluctuations. Recently, unified field theories have taught us that the mass of the electron is certainly not...

Homework Statement For silicon at T=300K with donor density ND=2×109cm−3, acceptor density NA=0 and ni=8.2×109cm−3, calculate the equilibrium electron and hole concentration Homework Equations n_0=\frac{N_D-N_A}{2}+\sqrt{\frac{N_D-N_A}{2}^2+n_i^2} p_o=\frac{n_i^2}{n_0} The Attempt at a...

Homework Statement What is the radius of the orbit of an electron traveling at 9.0 x 10^6 m/s around a zinc nucleus which contains 30 protons? Homework Equations I don't know if this problem can be solved quantum mechanically, all I can think of doing is solving it classically, using Coulomb's...

Is a photon fully absorbed by a electron in metal? Ejected electron is a free electron or bonded one? Is it possible to have a zero work function? If not why? I want to study about this detaily ,can you prefer some reference papers?

What is the probability of an electron being found outside the atom it belongs to? Is it zero or nonzero?

Homework Statement An electron in a hydrogen atom falling from an excited state to the ground state has the same wavelength than an electron moving at a speed of 7821 ms^-1. From which excited state did the electron fall from? Homework Equations I used the kinetic energy equation: K = (m...

I couldn't fit the whole question, it should say "How close does an electron have to get to a proton to be attracted to it" And I know it can depend on the speed and direction they are traveling. Can we just pretend they are stationary for this answer please. By attracted I mean the electron...

Hi I am surprised to know why only one photon in photoelectric effect ejects one electron only. What if a high energy photon (not necessarily x-ray or gamma ray, which may cause Compton effect or pair production)hits the metal, say it has energy double or triple of that of the work function? Why...

Homework Statement A photon of wavelength 300nm is emitted from an atom when an electron makes a transition from an energy state of -4 eV to a state of -8 eV. IF the initial state had been at enerygy of -6 eV, the wavelength of the photon emitted in a transition to -8eV is..?? Homework...

pg. 243 Falconer, I. (1987) Corpuscles, Electrons and Cathode Rays: J.J. Thomson and the Discovery of the Electron. The British Journal for the History of Science (BJHS, 1987,20,241-276). "One of their most important properties is that they are deflected by a magnetic field. This provided strong...

So, I've been reading a whole bunch of different answers to this online. Some people say yes, some people say no. I'm totally confused...

Homework Statement An electron and a proton are each placed at rest in an electric field of 687 N/C. What is the velocity of the electron 56.5 ns after being released? Consider the direction parallel to the field to be positive. The fundamental charge is 1.602×10−19 C, the mass of a proton is...

What are the different signals we obtain from TEM and How can we distinguish between them? what are the significances of those signals?

Is it reasonable to assume that the energy of the electrons used to power a diode, equals the energy of the photons emitted from the diode? If so, why?

In my study of Quantum physics i have arrived at the natural shielding caused by photon to electron/anti-electron pair fluctuations.The shielding reduces as you get closer the electron which naturally leads me to the question.What actually is the charge on an electron?

Homework Statement An Electron with an initial speed of 500,000m/s is brought to rest by an electric field a)did the electron move into a region of higher or lower potential? I b) what was the potential difference that stopped the electron? Homework Equations ΔV=ΔU/q ΔU=-W The Attempt at a...

I have am currently reading Radiation Detection and Measurement, by Gleen F.Knoll, and in chapter 10 page 309. And have come across something that is causing a bit of confusion, for context the chapter is on gamma ray spectroscopy. So in the text it say's 'Thus the effect of photoelectric...

If an electron were to be spontaneously created at a point somewhere in space, would the electron's field expand outwardly at the speed of light, regardless of frame, just like how a flash of light would expand outward at the speed of light, regardless of frame?

Homework Statement Hello PF! Got a two-part question involving calculating the electric force on a electron when placed in an electric field of 0.75N/C to the right, and the acceleration of said electron. Our values are E=0.75N/C, q=-1.6e^-19, m=9.1e^-31 (charge and mass of electron)...

In practice, ESR/EPR seems to concern only unpaired electrons in the outer layers of organic radicals or complexes. But what about the free electrons of metals? Does it also give rise to a signal? I can't find any information on the web. Thanks

Do you know when the energy content of electrons was actually measured as .511 MeV? was the first measurement true to current value? and, most of all, how was/is it measured with precision?

Homework Statement Is there a minimum value for the total energy of the electron (in this analysis)? The previous parts: Use Larmor formula to find ##\frac{|\Delta E|}{K}##, where ##|\Delta E|## is the energy lost per revolution. the result is ##\frac{8\pi v^3}{3c^3}##. ##\frac{v(r)}{c}## was...

Homework Statement Find an expression for the time it takes for an electron to spiral in from an initial radius ##r_i## to a final radius ##r_f##. Write your answer in terms of ##r_i##, ##r_f##, ##m_e##, e, and c. Homework Equations Larmor Formula: $$\frac{dE}{dt} =...

if a random electron strikes a neutral conductor does it get absorbed and increase the voltage of the conductor

Hello How should i calculate number of electrons passing through it when we apply some gate voltage across it

Homework Statement A point charge of -1.0 µC is located at the origin. A second point charge of 16 µC is at x = 1 m, y = 0.5 m. Find the x and y coordinates of the position at which an electron would be in equilibrium. Homework Equations F=k((q1q2)/r^2) The Attempt at a Solution I have gotten...

Why is the electric potential of an electron in a capacitor measured from the negative plate and not the positive plate here? This is from Liboff Introductory quantum mechanics 1st(current is 4th) edition: I don't understand why the distance z is measured from the bottom plate if the...

Hello! I found this problem where we are asked what happens to the energy of the outgoing photon in a Compton interaction, if the mass of the electron goes to zero and what is the physical intuition of it. So the formula is this: $$\lambda - \lambda_0 = \frac{h}{m_0 c}(1-cos \theta)$$ So when...

When do we use the Boltzmann equation for density in a Fermi plasma? n in [cm-3] and when do we use the ρ=m/V, ρ in [Kg/m3 ] (this is not an example, I just added the equations to make my question more understandable) Is the ideal gas only when we have electron and ions? Is the Boltzmann...

Homework Statement In the figure, an electron of mass m, charge − e, and low (negligible) speed enters the region between two plates of potential difference V and plate separation d, initially headed directly toward the top plate. A uniform magnetic field of magnitude B is normal to the plane...

Why all particles of same type identical? All electrons are identical to each other, all protons are identical..etc. It is as if they are copy pasted from each other! For me this is one of the biggest mysteries ever, why we don't detect more massive or less massive electrons? Is it related...

How electron revolves around orbitals? Is the velocity uniform or accelerated?

what are the dimensions of the double slits in comparison to the electron? what keeps the electron from decaying outside the environment of an atom long enough to run the experiment? how are the electrons detected before and after the slits?

No physicist has ever seen an electron. Yet, all physicists believe in the existence of electrons. An intelligent but superstitious man advances this analogy to argue that 'ghosts' exist even though no one has seen one. How will you refute his argument?

So I read a couple of explanations of how night-vision equipment works. Unfortunately I don't remember the sources but my recollection/understanding is that infrared light is converted into electrons and then into visible light. So my question is how does the information by which I mean (the...