Is ψ(x) = a0exp(-βx²) an Eigenfunction of the Hamiltonian?

Can you figure out what it is?In summary, the conversation discusses finding the eigenfunction and energy for a particle moving in a one-dimensional potential. The function ψ(x) = a0exp(-βx2) is proposed as an eigenfunction and the Hamiltonian is applied to determine the value of β. After some confusion, it is discovered that setting the Hamiltonian to zero and cancelling out terms leads to the conclusion that β=mω/2hbar. This value of β allows the Hamiltonian to be written as a constant times the original wave function, satisfying the eigenfunction condition.
  • #1
phys2
22
0

Homework Statement



A particle moves in a one dimensional potential : V(x) = 1/2(mω2x

Show that the function ψ(x) = a0exp(-βx2) is an eigenfunction for the Hamiltonian for a suitable value of β and calculate the value of energy E1

Homework Equations





The Attempt at a Solution



What I did was take the Hamiltonian, differentiate twice the function ψ(x) and then sub in the twice differentiated function along with the potential into the Hamiltonian. But there I get confused. Apparently taking a peek at the solutions, it argues that you should set the Hamiltonian to zero and then since it is supposed to be a constant, the x^2 terms cancel out and your final answer is β=mω/2hbar. I have no idea what they have done though! Any one care to explain? Thanks!
 
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  • #2
phys2 said:

Homework Statement



A particle moves in a one dimensional potential : V(x) = 1/2(mω2x

Show that the function ψ(x) = a0exp(-βx2) is an eigenfunction for the Hamiltonian for a suitable value of β and calculate the value of energy E1

Homework Equations





The Attempt at a Solution



What I did was take the Hamiltonian, differentiate twice the function ψ(x) and then sub in the twice differentiated function along with the potential into the Hamiltonian.
Show us what you got when you did that. If ##\psi## is an eigenfunction of ##\hat{H}##, what does ##\hat{H}\psi## have to equal?

But there I get confused. Apparently taking a peek at the solutions, it argues that you should set the Hamiltonian to zero and then since it is supposed to be a constant, the x^2 terms cancel out and your final answer is β=mω/2hbar. I have no idea what they have done though! Any one care to explain? Thanks!
 
  • #3
So I got -h(bar)2/2m (4β2x2) ψ + 1/2mω2x2ψ = Hamiltonian

Hψ=Eψ?
 
  • #4
phys2 said:
So I got -h(bar)2/2m (4β2x2) ψ + 1/2mω2x2ψ = Hamiltonian
You're missing a term. You didn't differentiate correctly, perhaps.

Hψ=Eψ?
Right, so after applying the Hamiltonian, you should be able to write the result as a constant times the original wave function. To do that, β will have to take on a specific value.
 
  • #5


I would like to clarify the steps needed to solve this problem. First, we have to understand the concept of eigenfunctions in Hamiltonian quantum mechanics. Eigenfunctions are special wavefunctions that satisfy the Schrödinger equation and represent the energy states of a system. These eigenfunctions are characterized by their corresponding eigenvalues, which represent the energy of the system. In this problem, we are given a potential function V(x) and we are asked to find the eigenfunction ψ(x) and its corresponding eigenvalue E1.

To solve this problem, we need to use the Schrödinger equation, which is given by:

Hψ(x) = Eψ(x)

Where H is the Hamiltonian operator, ψ(x) is the wavefunction, and E is the energy.

To find the eigenfunction ψ(x), we need to solve the Schrödinger equation for a given potential function V(x). In this case, the potential function is V(x) = 1/2(mω2x). So, we can write the Schrödinger equation as:

-ħ^2/2m(d^2ψ(x)/dx^2) + 1/2(mω2x)ψ(x) = Eψ(x)

Next, we substitute the given wavefunction ψ(x) = a0exp(-βx2) into the Schrödinger equation and solve for the value of β. This step involves differentiating the wavefunction ψ(x) twice and then substituting it into the Schrödinger equation. After simplifying, we get:

β = mω/2ħ

This is the value of β that satisfies the Schrödinger equation for the given potential function V(x).

To calculate the value of the energy E1, we need to substitute the value of β into the Schrödinger equation and solve for E. This will give us the eigenvalue corresponding to the given eigenfunction ψ(x). After solving the equation, we get:

E1 = 1/2ħω

This is the value of the energy corresponding to the eigenfunction ψ(x) = a0exp(-βx2).

In conclusion, Hamiltonian quantum mechanics is a powerful tool that allows us to find the energy states of a system by solving the Schrödinger equation. By using the
 

FAQ: Is ψ(x) = a0exp(-βx²) an Eigenfunction of the Hamiltonian?

What is Hamiltonian quantum mechanics?

Hamiltonian quantum mechanics is a mathematical framework used to describe the behavior of quantum systems. It involves the use of operators and wave functions to represent physical quantities and their evolution over time.

How is Hamiltonian quantum mechanics different from classical mechanics?

Hamiltonian quantum mechanics differs from classical mechanics in several ways. In classical mechanics, the state of a system can be precisely determined at any point in time, while in quantum mechanics, the state of a system is described by a wave function that represents a range of possible states. Additionally, in classical mechanics, physical quantities are represented by real numbers, while in quantum mechanics, they are represented by operators that act on the wave function.

What is the role of the Hamiltonian operator in quantum mechanics?

The Hamiltonian operator is a key component of the Hamiltonian quantum mechanics framework. It represents the total energy of a system and is used to determine the time evolution of a quantum system through the Schrödinger equation.

How is the Hamiltonian operator related to the concept of energy?

The Hamiltonian operator is related to energy through the Hamiltonian function, which is a mathematical expression that represents the total energy of a system. The Hamiltonian operator acts on the wave function to determine the energy of the system at any point in time.

What are some applications of Hamiltonian quantum mechanics?

Hamiltonian quantum mechanics has many applications, including in the fields of quantum chemistry, solid-state physics, and quantum computing. It is also used to study the behavior of particles in particle accelerators and to model complex systems in biology and economics.

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