Simple harmonic oscillator Hamiltonian

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SUMMARY

The discussion centers on the Hamiltonian of a simple harmonic oscillator, specifically the expression $$\hat{H} = \frac{1}{2}mw^2\hat{x}^2 + \frac{\hat{p}^2}{2m}$$. It demonstrates how the time-independent Schrödinger equation can be represented as $$\hbar w \Big(a^{\dagger}a+\frac{1}{2}\Big)|\psi>=E_n|\psi>$$. A key point raised is the potential confusion between the Greek letter omega (ω) and the Latin letter w in the context of angular frequency. The mathematical derivation confirms the validity of the Hamiltonian formulation for quantum mechanics.

PREREQUISITES
  • Understanding of quantum mechanics principles, particularly Hamiltonian mechanics.
  • Familiarity with the time-independent Schrödinger equation.
  • Knowledge of operators in quantum mechanics, specifically creation (a†) and annihilation (a) operators.
  • Basic grasp of commutation relations, particularly between position (x) and momentum (p) operators.
NEXT STEPS
  • Study the derivation of the time-independent Schrödinger equation for various potential systems.
  • Learn about the role of creation and annihilation operators in quantum harmonic oscillators.
  • Explore the implications of the Hamiltonian formulation in quantum mechanics.
  • Investigate the differences between Greek and Latin symbols in scientific notation to avoid confusion.
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Students and professionals in physics, particularly those focusing on quantum mechanics, theoretical physicists, and anyone studying the mathematical foundations of quantum systems.

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Homework Statement
please see below
Relevant Equations
please see below
Screen Shot 2021-02-11 at 3.33.10 PM.png

We show by working backwards
$$\hbar w \Big(a^{\dagger}a+\frac{1}{2}\Big)=\hbar w \Big(\frac{mw}{2\hbar}(\hat{x}+\frac{i}{mw}\hat{p})(\hat{x}-\frac{i}{mw}\hat{p})+\frac{1}{2}\Big)$$
$$=\Big(\frac{mw^2}{2}(\hat{x}^2+\frac{i}{mw}[\hat{p},\hat{x}]+\frac{\hat{p}^2}{m^2w^2})+\frac{1}{2}\Big)=\frac{1}{2}mw^2\hat{x}^2-\frac{\hbar w}{2}+\frac{\hat{p}^2}{2m}+\frac{\hbar w}{2}$$
$$=\frac{1}{2}mw^2\hat{x}^2+\frac{\hat{p}^2}{2m}=\hat{H}$$
This shows the time-independent Schrödinger equation for the simple harmonic oscillator can be written as
$$\hbar w \Big(a^{\dagger}a+\frac{1}{2}\Big)|\psi>=E_n|\psi>$$
 
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I think you confuse the greek letter ##\omega## with the latin letter ##w## ...
Ssnow
 

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