State Definition and 1000 Threads

The muon is a subatomic particle with the same charge as an electron but with a mass that is 207 times greater: mμ=207me. Physicists think of muons as "heavy electrons." However, the muon is not a stable particle; it decays with a half-life of 1.5 μs into an electron plus two neutrinos. Muons...

I know how to solve this problem when the energy at ground state is zero but I don't know how to deal with 1st excited state energy as zero. According to me since the potential energy is zero therefore the kinetic energy must be 13.6eV according to conservation of energy. I also know that the...

I have written a finite difference program to solve 1D time-independent Schrodinger equation. It seems to work correctly for harmonic oscillator, particle in a box, etc. But I can't figure out how to calculate the probability current density. It should be constant, but what is it? The program...

I am working through David Griffiths' "Introduction to Quantum Mechanics". All of the solutions are provided online by Griffiths himself. This is Problem 2.5(e). I understand his solution but I'm confused about one thing. After normalizing Ψ, we find ##A=\frac {1}{\sqrt2}##. Griffiths notes that...

I need this for a programming project. Could you help?

I would like to see what the shape of the ground state radial wavefunction for the Lithium atom is. An approximate function that shows the shape would be fine. Thanks.

I'm trying to delve into the reason why this is so. It seems that there are 5 fundamental properties: P - Pressure V - Volume (specific) T - Temperature S - Entropy (specific) U - Internal Energy (Yes, there are other types of energy, but they are fully determinable from these 5 - e.g...

Hi all, One more virtual particle question (sorry all!): for individuals who would take virtual particles as being 'real' (but unobservable), what is their understanding then of the content of the vacuum? For example, if I place a electron all by itself in the vacuum (thus making it no longer...

In some other thread someone mentioned that a 3D cubic potential well always has a ground state that is a bound state, but a spherical well doesn't necessarily have if it's too shallow. I calculated some results for 3d cubes, spheres and surfaces of form ##x^{2n}+y^{2n}+z^{2n}=r^{2n}##, which...

Here is a question I have been given I have started by setting up the formula and rearranging for n_2 Only problem is that I do not know the quantum number for ground state? What value do I sub in for n_1? Any help would be appreciated! Thanks

I know |GHZ>=(1/sqrt(2))[1; 0; 0; 0; 0; 0; 0; 1], and |000>= the tensor product |0> x |0> x |0> = [1; 0; 0; 0; 0; 0; 0; 0]. Can I apply single qubit gates (i.e. 2x2 matrices) and CNOT (a 4x4 matrix) to 8x1 column vectors? If so, does anyone know a good starting point or a hint to get me moving...

I'm in a first-year grad course on statistical mechanics and something about multivariable functions that has confused me since undergrad keeps popping up, mostly in the context of thermodynamics. Any insight would be much appreciated! This is a general question, but as an example imagine...

A particle of mass m is in the ground state on the infinite square well. Suddenly the well expends to twice it's original size (x going from 0 to a, to 0 to 2a) leaving the wave function monetarily undisturbed. On answering, for ##\Psi_{n}## I got ##\Psi_{n}## = ##\sqrt{\frac{1}{a}}...

Is it easier to enforce a lockdown in an AUTHORITARIAN state than in a liberal democratic state like ours? I think so! In centrally commanded economies, whatever the Politburo orders, goes... In a LIBERAL DEMOCRACY like ours, we all shout in a chaotic noisy cacophony, all wanting our voices...

Why energy of the electron in ground state of hydrogen atom is negative ##E_1=-13,6 \rm{eV}##? I am confused because energy is sum of kinetic and potential energy. Kinetic energy is always positive. How do you know that potential energy is negative in this problem?

Hey there, the task I'm working on is written below. Find the quadrature distribution ρ(q), for an optical mode being in the coherent state |α>. Hint: use ∑Hn(x)*(t^n)/(n!) I really am struggling with this type of tasks :D I tried to follow a solved example that I found in my workbook, but...

Hello all: I was wondering are we have a name for protein structure , or we consider them amorphous? Any one did a phono propagation in protein molecules ? Protein folding and phonons any relationship? When peptides came together and start to form the protein dose phonons/photon propagation...

As the temperature given was 0K, I calculated the ground state energy of the system. I considered 2 electrons to be in the n=1 state, 2 in the n=2 state and 1 in the n=3 state by Pauli's exclusion principle. By this configuration, I got the total energy of the system in the ground state to be...

I’ve never worked with a quantum system with more that two states 1, -1, and I’ve just gotten this homework problem. I'm not sure what it means. Does this mean it has five states? Why are there two 0’s and two 1’s?

question fig: solution manual: my solution: oxidation state of central cobalt is +6 due to 6 oxygen surrounding it,The other cobalt is +2 due to 2 oxygen surrounding it with NH3 ligand which is no count for oxidation state.

Hello everyone, I am an undergraduate doing research in quantum optics, and my topic involves 50:50 beam splitters and studying entanglement for different input states. I came across a paper which I am using as a guide for now, but I wanted to derive a result they had and have been working on it...

Hi there, popping by here to check my answer because another online platform has already answered it but my answer appears to be wrong. I can't seem to understand why though :/ Since I can find the energy at a state to be ##E_{n}=\dfrac {-13.6z^{2}}{n^{2}}eV## At ground state where n=1...

This is the equation given. I attempted to use Radial Equation, obtained from separating variables, to solve for ##E_1##.

In a (reversible) Carnot cycle the entropy increase of the system during isothermal expansion at temperature TH is the same as its decrease during isothermal compression at TC. We can conclude that the entropy change of the system is zero after a complete Carnot cycle. The mentioned textbook now...

Hi, The context for my question is: A thin plate, which lies in the x-y plane, contains a small hole of radius a . Consider a polar co-ordinate system r,􏰆 with its origin at the centre of the hole and 􏰆defined as the angle that a radial line makes with the x-axis. A uniform uniaxial tensile...

I introduced the unitary transformation ##U=U_a \otimes U_b## with ##(U_a\otimes 1):\;|s,s> \rightarrow\,\frac{1}{\sqrt{d}}\sum_t \omega^{ts}|t,s> ## und ##(1\otimes U_b):\;|s,s> \rightarrow\,\frac{1}{\sqrt{d}}\sum_t \omega^{-ts}|s,t> ## ##(\omega=e^{2\pi i/d}##) and let it act on the state in...

Hi, Gravitational energy in de Sitter has equation of state w=-1 (cosmological constant) and w=-1/3 (curvature energy in open or closed de Sitter). Is this just gravitational radiation, and how does this accord with the equation of state of photon radiation w=1/3? Does this mean that densities...

I have read some materials about quantum hall effect and know that at the edge of a 2D material , one can linearize the potential V and the linear dispersion relation represents right/left moving fermion. So , Can I say that for a given hamiltonian , if I can linearizae it at edge, then this...

Hi, I have been taught that quarks don't exist individually on their own, as they has with be with at least another antiquark to form a colorless state. But in the quark-gluon plasma, do we have individual quarks in a color state or do they still, somehow, are in a color-neutral state? Thanks!

As a simple example, the probability of measuring the position between x and x + dx is |\psi(x)|^{2} dx since |\psi(x)|^{2} is the probability density. So summing |\psi(x)|^{2} dx between any two points within the boundaries yields the required probability. The integral I'm confused about is...

(This question is on the elementary side...) In the Schrödinger picture, the state is dependent on time. If you have a state composed of several particles, generally you can break them up, with each one depending on local time. But in an entangled system, say of two particles, you can no longer...

What happen if a small energy photon collide an atom in ground state that the gap between energy levels of atom is greater than energy of photon?It seems that the medium absorbs light and transform to heat?

I am attempting to understand how POVMs fit in with quantum measurement, and I think I am getting tripped up in notation when it comes to multipartite systems. The situation is as follows: System: \rho_A Measurement instrument: \rho_B = |\phi\rangle\langle\phi| (pure state) The multipartite...

The picture shown below is one triplet state and one singlet excited state of molecular orbitals. According to Hund's Law, the triplet state, which has 2 electrons with parallel spin, has lower energy than the singlet state. I went through some papers, only to be told that the triplet state has...

In BEC, why do we separate the number of particles of ground state(E=0) from the integral(total number of particles) when temperature below critical temperature. Why is the overall integral wrong while the index of sum of number of particle can be considered as continuous? Is it correct that...

I am certain this has been answered...but I missed it. Why do so many guitar players swear by TUBE amps? My son-in-law says they just sound better. Because I was a TV/Radio service tech for 20 years with a degree from Elkins Institute, he asks me why? My guess was, maybe amplifying a signal...

I guess the hard way is to solve the Schrödinger equation, but that would be exhausting. I think the F-H theorem would not apply here. So do the Virial theorem. Are there other theorems I forget?

Hi , reading some notes on quantum hall effect, a comparison between Moore-Read wavefunction and Laughlin wavefunction is ' the moore-read state has fewer zeros suggesting the particles are more densely packed' Just confused with understanding why fewer zeros means the particles are more...

Hi , I'm looking at the argument in David Tongs notes (http://www.damtp.cam.ac.uk/user/tong/qhe/three.pdf) for ground state degeneracy on depending on the topology of the manifold (page 97, section 3.2.4). I follow up to getting equation 3.31 but I'm stuck on the comment after : ' But such an...

first state whether it can be solved using the Master Theorem, and if it can then use that. Otherwise, use the Akra-Bazzi formula. 1. T(n) = 3T([n/3])+n 2. T(n) = T([n/4])+T([n/3])+n 3. T(n) = 2T([n/4])+√n

Hi, I am currently studying solid-state physics course from Charles Kittel's "introduction to SSP" I searched more on youtube to get lectures to follow the book of Kittel but failed. Really I would appreciate if anybody advises me online source which can help me to comprehend the contents of...

Attached is what I have so far. I believe it is done but I am not 100% sure. It seems to me like every case is considered. For each state, and output of a,b, or c is possible.

##\newcommand{\ket}[1]{|#1\rangle}## ##\newcommand{\bra}[1]{\langle#1|}## I have a momentum-shifting operator ##e^{i\Delta p x/\hbar}## acting on the ground state ##\ket{0}## of the QHO, and I want to compute the overlap of this state with the n##^{th}## excited QHO state ##\ket{n}##. Given...

I am performing ab initio calculations on a heteronuclear diatomic compound using the MRCI method on the MOLPRO quantum chemistry package. I obtained the molecular states of the compound but I was wondering how to find the molecular orbital configuration of each electronic state in addition to...

As a non-Physics major, like many others, I read science-fiction, hard science-fiction, have undergraduate/graduate courses on Astronomy and college physics. I also participated in R&D that produced electric rockets able to power small space vehicles (very slowly, but surely). I deal with...

If I'm using the basis vectors |u> and |r> for two polarisation states which are orthogonal in state space, I've seen the representation of a general state oriented at angle theta to the horizontal written as $$\lvert\theta\rangle = \cos(\theta) \lvert r \rangle + \sin(\theta) \lvert u...

As far as I know we can express the position and momentum operators in terms of ladder operators in the following way $${\begin{aligned}{ {x}}&={\sqrt {{\frac {\hbar }{2}}{\frac {1}{m\omega }}}}(a^{\dagger }+a)\\{{p}}&=i{\sqrt {{\frac {\hbar }{2}}m\omega }}(a^{\dagger }-a)~.\end{aligned}}.$$...

Most molecules are in singlet ground state which is of higher energy than triplet lower energy state .According to thermodynamics molecule tend to remain in lower energy state.Therefore,I presume molecules should remain in triplet state .Could anyone clarify my point

Do electrons have motion or they just accelerate when they get enough energy?