Entanglement
Quantum Mechanics · Part 9
223 KB10 sections4 key equationsLaTeX typeset
Table of Contents
- 1.Product States vs. Entangled States
- 2.Bell States: Maximally Entangled Pairs
- 3.Schmidt Decomposition
- 4.Density Matrix of a Subsystem
- 5.Entanglement Entropy
- 6.Purity and the Entanglement Connection
- 7.Detecting Entanglement: Witnesses and the PPT Criterion
- 8.Proof Sketch
- 9.Schmidt Number as Entanglement Measure
- 10.Example: Bell State Entanglement
Key Equations
$$|\psi\rangle_{AB} = |\phi\rangle_A \otimes |\chi\rangle_B$$
$$|\Psi^+\rangle = \frac{1}{\sqrt{2}}\left(|01\rangle + |10\rangle\right), \qquad |\Psi^-\rangle = \frac{1}{\sqrt{2}}\left(|01\rangle - |10\rangle\right)$$
$$\boxed{S(\hat{\rho}_A) = -\text{Tr}\!\left(\hat{\rho}_A \ln\hat{\rho}_A\right) = -\sum_{i=1}^{r} \lambda_i \ln\lambda_i}$$
$$\gamma(\hat{\rho}_A) = \text{Tr}\!\left(\hat{\rho}_A^2\right) = \sum_i \lambda_i^2$$
Equations are rendered with MathJax in the PDF with professional LaTeX typesetting.
Course Context
This PDF is part of the Quantum Mechanics course on CoursesHub.World. Master quantum mechanics from mathematical foundations to advanced topics. Covers Hilbert spaces, wave functions, angular momentum, perturbation theory, scattering, and path integrals with 450+ pages ...