Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with quantum-mechanics
Search options not deleted
user 290499
Quantum mechanics describes the microscopic properties of nature in a regime where classical mechanics no longer applies. It explains phenomena such as the wave-particle duality, quantization of energy, and the uncertainty principle and is generally used in single-body systems. Use the quantum-field-theory tag for the theory of many-body quantum-mechanical systems.
0
votes
3
answers
640
views
Finite Potential Barrier Where $E=V_0$
If we have a free particle of energy E incident on a potential $V$
$$V(x) = \begin{cases}0 & x \leq 0 \\ V_0 & 0 < x < L \\ 0 & x \geq L\end{cases}$$
We find that the wave function $\phi$
$$\phi(x) = …
- 267
0
votes
1
answer
30
views
How is the measurement of the $Z_0Z_2$ error syndrome realised by these two circuits?
I am told that the following quantum circuit diagram implements the $Z_0Z_2$ error syndrome, but I don't follow.
I understand error syndromes when expressed in matrix form and how performing $Z_0Z_2| …
- 267
0
votes
1
answer
130
views
Why must normalisable eigenfunctions have $E > V_{min}$? [duplicate]
I have read normalisable eigenfunctions of the Hamiltonian operator.
$$\hat{H}\phi = E\phi$$
If $\phi$ is to be normalisable we must have $E > V_{min}$
Why is this?
- 267
0
votes
1
answer
83
views
Derivation of QFT product formula
If the quantum fourier transform is defined as follows:
$$
U_{FT} |x\rangle = \frac{1}{2^{n/2}} \sum^{2^n-1}_{y=0} e^{2\pi i x y / 2^n} | y \rangle.
$$
We can rewrite the exponential term as:
$$
e^{2\ …
- 267
3
votes
1
answer
707
views
Understanding the probability of measurement w.r.t. density matrix
I am told that the probability of measuring $\lambda$ is $$p_\lambda = Tr(\hat{P}_\lambda\hat{\rho}) = Tr(\hat{P}_\lambda\hat{\rho}\hat{P}_\lambda)$$ where $\hat{P}_\lambda = \sum_{n:\lambda_n = \lamb …
- 267
11
votes
2
answers
2k
views
Why is the trace of the outer product of two states equal to the inner product of the two st...
Why is it that, given two quantum states $|\psi_1\rangle$, $|\psi_2\rangle$,
$$\mathrm{Tr}(|\psi_1\rangle\langle\psi_2|) = \langle\psi_2|\psi_1\rangle \quad $$
I went through the equation with the qub …
- 267