Superposition Definition and 673 Threads

When I'm solving a superposition principle problem i get stuck and so confused with the signs. For example this problem Consider three point charges at the corners of a triangle, as shown at right, where q1 = 6.00 × 10−9 C, q2 = −2.00 × 10−9 C, and q3 = 5.00 × 10−9 C. Find the magnitude and...

Does measuring a polarized photon after it passed a polarization filter put the measurement apparatus in a superposition of detected/not-deteced (the photon)? Does this depend on whether the photon is part of an entangled pair?

Homework Statement For the network of constant current shown in Figure 4 it is known that R1 = 50 Ω and , R = 10 Ω. When the switch P is in the 1-position , current I = 50 mA and Ip = 70 mA known i . When the switch P is in the 2-position , current I' = 40 mA and Ip' = 90 mA are known ...

I get that a if we have complete information of the state of the system (i.e. all the possible knowledge we could have about it: the values its observables can take and their corresponding probabilities), then it is a pure state and can be represented by a vector (ket), ##\lvert\psi\rangle## in...

Homework Statement The three lowest energy states of an infinitely deep square well (of width L, between x=0 and x=L) are: Ψ1(x,t) = N sin(πx/L) e-iω1t Ψ2(x,t) = N sin(2πx/L) e-iω2t Ψ3(x,t) = N sin(3πx/L) e-iω3t N = sqrt(2/L) is the normalization, to make the total probability = 1. Each wave...

Hello suppose that we are dealing with a particle moving in an infinite potential well(a box of length L). Let the wavefunction of the particle be \psi(x,t)=c1\psi_{1}(x,t)+...+cn\psi_{n}(x,t) suppose that after measurement we find the particle at the energy eigenstate \psi_{1}(x,t). Now let's...

Can someone explain the difference using concrete examples. I will attempt to explain my current understanding by example; A H atom has different energy levels which can be exactly described by algebraic functions with quantum numbers n, l etc. An electron can be excited from say the ground...

I am aware that there have been a few posts about this, I read most of them so I just want to confirm that what I've picked up is correct. The principle of superposition only applies to forces that depend linearly on some quantity (charge and mass for example), and since we wouldn't know...

I am preparing for a qualifying exam for my PhD program and am looking at some of the old tests from previous years (as supplied by the school for study/prep material). I have come across a deflection problem that has me stumped, and I might just be overthinking it. The problem:

Perhaps someone can show me some simple math showing two states in superposition and entanglement so I can see how entanglement relates to superposition. Thanks.

I wanted to post the conjecture from this new paper which has recently been published within this past month - here's a direct link to the paper: http://arxiv.org/pdf/1602.01439v1.pdf Could an experimental apparatus consisting of oscillating masses be used to generate miniscule gravity waves...

Homework Statement [/B] Particle in one dimensional box, with potential ##V(x) = 0 , 0 \leq x \leq L## and infinity outside. ##\psi (x,t) = \frac{1}{\sqrt{8}} (\sqrt{5} \psi_1 (x,t) + i \sqrt{3} \psi_3 (x,t))## Calculate the expectation value of the Hamilton operator ##\hat{H}## . Compare it...

Hi all, You can use superposition to add moments of inertia when they're calculated about the same center of gravity (cg), but let's say you calculate the moments of inertia of several elements of a system about one cg and then use the Parallel Axis Theorem to then reference the total moments...

So I heard the news today about gravity waves being confirmed. I really like learning about all the different types of waves and would like to expand my knowledge on gravitational waves. So, do gravitational waves abide by the superposition principle/property? Does anyone suggest a website or...

A particle in a quantum harmonic oscillator can be in a superposition of energy eigenstates, and so the energy is not well-defined. However, energy is still conserved, so if I understand it correctly the "uncertainty" in the superposition's energy must be matched by uncertainty elsewhere in the...

What is the relation between "superposition" and "the Heisenberg uncertainty relation"?

I have a question regarding superposition and its relation with interpretations/counterfactual definiteness. I've seen this question brought up a few times when browsing through forums although I don't think it has ever been fully addressed. I've heard that counterfactual definiteness is not...

I have a very basic question about superposition. Suppose two experimenters do a measurement on a particle in superposition. Does de measurement apparatus become in superposition? Do the experimenters become in superposition? What is superposition?

look to post 3. original question had a lot of misconceptions.

Okay, the task is really not that hard but I am getting strange numbers. 1. Homework Statement Find the current going through the resistor of 18 ohms. Circuit is shown in the first picture. Homework EquationsThe Attempt at a Solution I used norton theorem and superposition to find current In

Modeling driven undamped spring systems in my diff eqs text at the moment. So I've just worked through the derivation of x(t) = C\cos{(\omega_0t - \alpha)} + \frac{F_0/m}{\omega_0^2-\omega^2}\cos{\omega t} And it's clear that this describes the superposition of two different oscillations...

I am wondering if my understanding of superposition concept is correct. Forgive me for not using QM braket notation, I am new on this site and don't know how to embed it in the post. What confuses me about superposition concept is that people often say that some system can be in two (or more)...

Hello, my question is a bit broad but it is as follows; when a particle is in superposition do any laws affect or limit the possibilities for that particle. An example would be if a particle is observed in space then during another instant it is not observed will that particle be at the edge of...

I'm wondering if a system regains its superposition after it's observed or if it remains a definite value forever after observation. Also, if a system does regain its superposition, does it occur instantly after it's done being measured?

Context of this post (skim or skip, but read the last paragraph): I like to teach things to people, especially those who believe that they won't understand. For those hard cases you almost have to trick them into learning something. That is, just start building up concepts in simple terms...

Homework Statement For an infinite potential well of length [0 ; L], I am asked to write the following function ##\Psi## (at t=0) as a superposition of eigenstates (##\psi_n##): $$\Psi (x, t=0)=Ax(L-x) $$ for ## 0<x<L##, and ##0## everywhere else. The attempt at a solution I have first...

Homework Statement Three uniform spheres are fixed at positions shown in the figure. i) What is the magnitude of the force on a 0.0150-kg particle placed at P? ii) What is the direction of this force? iii) If the spheres are in deep outer space and a 0.0150-kg particle is released from rest...

We consider a one photon experiment. If the photon really follow both path at the first beam splitter then only one detector will click, if on the other hand the photon would have to choose one path (classical particle) then both detector could click ?

Homework Statement Given a orthonormal basis of the hilbert space of qutrit states: H = span (|0>, |1>, |2>) write in abstract notation and also a chosen consistent matrix representation, the states a) An equiprobable quantum superposition of the three elements of the basis b) An...

Pretty obvious that measuring at the double slits neutralizes whatever action or reaction is creating the wave pattern. But why the quantum leap to assuming superposition? What other configurations have been tested or were there just slits used? What about a round hole or holes, an “X” slit or...

In a double slit experiment (say, of electrons), when putting a detector to examine the passing of electrons through one slit, the wave pattern of the electrons disappears and instead the particle pattern appears. The classical explanation is that an electron exists both as a wave and as a...

Homework Statement a particle is in a linear superposition of two states with energy E_0 \ and\ E_1 |\phi> = A|E_0> + \frac{A}{(3-\epsilon)^{1/2}}|E_1> where: A \ > \ 0, \ 0\ <\ \epsilon \ <\ 3 What is the value of A expressed as a function of epsilon Homework Equations P(E_0) \ +\...

Homework Statement A double loop circuit is shown in the figure below.[/B] The Emf x = 6.00 V and the Emf w = 19.00 V. Both are shown on the diagram. Calculate the power dissipated in the 6 Ω resistor located on the extreme right in the circuit. Homework Equations V=IR, P=VI The Attempt at...

Homework Statement How does the pi-meson (π0) work without annihilating itself? Homework Equations |π0 〉1/√2 〉- {|uu − |dd} u= anti-upquark d= anti-downquark The Attempt at a Solution I do understand that it is a superposition, but why does it work when it is a partice with its own...

I was watching some Steve Spicklemire QM videos and had a question/check my knowledge.. When we measure a the state of a system, say a particle in a box or a quantum harmonic oscillator (QSHO), we "collapse" the superposition of the system and end up with one eigenstate and one eigenvalue...

Homework Statement Initially your receiver is positioned at a distance of 8.4 cm from the goniometer and recording a maximum intensity. You move it through 10 minimums in the intensity and then stop at the next maximum intensity. The receiver is now a distance of 27.3 cm from the goniometer...

Homework Statement Two particles, their spin are 1/2. The hamiltonian is ##H=\gamma s_1 \cdot s_2## At t=0, the state ##|\alpha(0)>## is such as ##s_{1z}|\alpha(0)>=\hbar/2 |\alpha(0)>## and ##s_{2z}|\alpha(0)>=\hbar/2 |\alpha(0)>##. Find the state ##|\alpha(0)>##.2. The attempt at a...

Homework Statement A rather large non conducting slab of area A and thickness d has a charge density given by ρ = αx2. The origin is through the center of the slab. That is, it bisects the slab into two equal volumes of d/2 thickness and with an area A, with -L/2 to the left of x=0 and L/2 to...

Homework Statement " Two traveling waves are generated on the same taut string. Individually, the two traveling waves can be described by the following two equations: If both of the above traveling waves exist on the string at the same time, what is the maximum positive displacement that a...

Hi, CMB photons reaching our telescopes have traveled for over 13 billion years without interacting with anything. If I understand correctly, from the event of the photon emission, its wavefunction gradually spreads, encompassing more and more possible states for the photon, coexisting in...

I have some troubles in finding coefficients of superposition of states. I have 2 particles, their spins are s1=3/2 and s2=1/2. At t=0, the system is described by |a(0)>=|3/2, 1/2, 1/2, 1/2> I have to find |a(t)>. I have thought to proceed in the following way: 1) use the basis |s, s_z>...

Hi all, I'm trying to understand how to calculate the time dependent expectation value of the atomic dipole moment for a superposition state, and I have a good guess to check with you. Say we have \psi = \frac{1}{\sqrt{2}} \left[ \psi _{100} + \psi _{310} \right] at t = 0. Then, for t > 0: \Psi...

Hi all, Quick quantum question. I understand the total angular momentum operation \hat{L}^2 \psi _{nlm} = \hbar\ell(\ell + 1) \psi _{nlm} which means the total angular momentum is L = \sqrt{\hbar\ell(\ell + 1)} But how about applying this to an arbitrary superposition of eigenstates such as...

Homework Statement I'm looking at an E&M textbook - "Time-Harmonic Electromagnetic Fields". They state: "A more general ##x ## polarized field is one consisting of waves traveling in opposite directions with unequal amplitudes - i.e : (1) $$ E_{x} = Ae^{-jkz} +Ce^{jkz}$$ Let ## A ## and...

Okay, so this is my first post, and I'm probably going to embarrass myself, but here goes. I have a bunch of questions. So we have an atom, consisting of a proton and electrons, and these electrons spin either clock wise or anti clock wise but in fact appear to do both... until measured...Is...

Homework Statement (f) At t = 0, a particle of mass m trapped in an infinite square well of width L is in a superposition of the first excited state and the fifth excited state, ψs(x, 0) = A (3φ1(x) − 2iφ5(x)) , where the φn(x) are correctly-normalized energy eigenstates with energies En. Which...

Why do we simply add the equations of SHM in case the two SHMs are superimposing?

I am confused by the my readings on the subject. Does superposition says that the system has all the values at the same time or it has one of the possible values but we don't know which one until "measured". And is there different answers for different observables. Moreover, how do these systems...

Homework Statement A quantum-mechanical harmonic oscillator with frequency ω has Hamiltonian eigenstates |n with eigenvalues En = (n + 1/2) ħω. Initially, the oscillator is in the state (|0> + |1>)/√2. Write down how the state of the oscillator evolves as a function of time t. Calculate the...

Homework Statement so there is this problem : find the amplitude from the superposition of Z1 and Z2 where Z1 : 8 sin 100t, A1= 8m and Z2 : 6 sin (100t-pi/2), A2=6m Homework Equations i know that all we need to do is add them and do the trig using sine additon, but i couldn't do that because...