Quantum Harmonic Oscillator Differential Equation help

In summary, the conversation discusses the equation for the quantization of the harmonic oscillator and its solution in the limit of y going to infinity. The solution is given as ψ= Ay^{m}e^{\pm y^{2}/2}, with the positive possibility in the exponential being ignored due to it not being in the physical Hilbert space. The speaker's question is how this differential equation was solved, and while some sources suggest guessing as a method, the expert summarizes that the solutions are known in terms of Modified Bessel functions or Parabolic Cylinder functions, and can also be found using the Frobenius method.
  • #1
cybla
16
0
Hi, so i am looking at the quantization of the harmonic oscillator and i have the following equation...

ψ''+ (2ε-y[itex]^{2}[/itex])ψ=0

I am letting y[itex]\rightarrow[/itex] [itex]\infty[/itex] to get...

ψ''- y[itex]^{2}[/itex]ψ=0

It says the solution to this equation in the same limit is...

ψ= Ay[itex]^{m}[/itex]e[itex]^{\pm y^{2}/2}[/itex]

The positive possibility in the exponential is ignored since it is not in the physical Hilbert space. My question is how did they solve this differential equation? I have read a couple websites and it says that you just have to "guess" it... however, is there a logical way to why you would guess this? Thank you
 
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  • #2
The solutions of this EDO are known in terms of Modified Bessel functions or alternately in terms of Parabolic Cylinder functions (in attachment)
 

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  • #3
For the ODE just use the Frobenius method. Series expansion.
 
  • #4
Okay i understand, thank you very much
 
  • #5
for your question. The solution to this differential equation is known as the Hermite function and it is a well-known solution to the quantum harmonic oscillator problem. The reason for guessing this particular form of the solution is based on the properties of the harmonic oscillator potential, which is a parabolic potential. The Hermite function is a solution to the Schrödinger equation for this type of potential and it is also a well-behaved and physically meaningful function. Therefore, it is a logical and reasonable choice for a solution to this differential equation. Additionally, the exponential term in the solution accounts for the wave-like behavior of the system. If you are interested in learning more about the derivation of this solution, I recommend studying the Schrödinger equation for the quantum harmonic oscillator in more detail.
 

1. What is a quantum harmonic oscillator differential equation?

A quantum harmonic oscillator differential equation is a mathematical equation that describes the behavior of a quantum mechanical system in which a particle is confined in a potential well and oscillates around an equilibrium position.

2. Why is the quantum harmonic oscillator differential equation important?

The quantum harmonic oscillator differential equation is important because it is a fundamental equation in quantum mechanics that helps us understand the behavior of particles in physical systems. It has applications in various fields such as quantum chemistry, solid state physics, and quantum computing.

3. How do you solve the quantum harmonic oscillator differential equation?

The quantum harmonic oscillator differential equation can be solved using various methods such as the power series method, the ladder operator method, and the matrix method. These methods involve using mathematical techniques to find the energy levels and wave functions of the system.

4. What are the boundary conditions for the quantum harmonic oscillator differential equation?

The boundary conditions for the quantum harmonic oscillator differential equation depend on the specific physical system being studied. However, in general, the wave function must be continuous and the first derivative of the wave function must also be continuous at the boundaries of the potential well.

5. How does the quantum harmonic oscillator differential equation relate to the classical harmonic oscillator equation?

The quantum harmonic oscillator differential equation is essentially the quantum mechanical version of the classical harmonic oscillator equation. However, unlike the classical equation which only considers the position and momentum of a particle, the quantum equation takes into account the wave nature of particles and introduces the concept of energy quantization.

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