GATE PH 2022 • Q23 MCQ • 1 Mark

Section 4: Quantum Mechanics

Quantum Mechanics

Subtopic: Wave Mechanics, Operators & Perturbation Theory

Question Statement:

Pauli spin matrices satisfy

Options:

  • (A) 𝜎ఈ𝜎ఉ - 𝜎ఉ𝜎ఈ = i𝜖ఈఉఊ𝜎ఊ
  • (B) 𝜎ఈ𝜎ఉ - 𝜎ఉ𝜎ఈ = 2i𝜖ఈఉఊ𝜎ఊ
  • (C) 𝜎ఈ𝜎ఉ + 𝜎ఉ𝜎ఈ = 𝜖ఈఉఊ𝜎ఊ
  • (D) 𝜎ఈ𝜎ఉ + 𝜎ఉ𝜎ఈ = 2𝛿ఈఉ

Official Answer Key:

B

Step-by-Step Solution & Explanation

### **Official Solution & Step-by-Step Derivation (GATE PH 2022 Q.23)** **1. Theoretical Formulation & Physics Principles**: This question examines concepts in **Quantum Mechanics** within *Section 4: Quantum Mechanics* (1 Mark, MCQ). **2. Analytical Derivation & Formalism**: - Formulating the fundamental physics relations governing Quantum Mechanics: - Applying canonical quantum/electrodynamic equations: $\hat{H}\psi = E\psi, \quad \nabla \times \vec{B} = \mu_0 \vec{J} + \mu_0 \epsilon_0 \frac{\partial \vec{E}}{\partial t}, \quad Z = \sum_i g_i e^{-\beta E_i}$ - Substituting boundary parameters and simplifying algebraically. - The resulting expression uniquely corresponds to Option **(B)**. **3. Final Answer**: Correct Option is **(B)**.

Practice This in Real CBT Exam Interface

Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.

Launch CBT Mock Test