Question on spin 1/2 states in arbitrary direction

In summary, the conversation discusses a problem involving finding gamma and beta in spin one half states in arbitrary directions. The person asking for help has attached their attempt at a solution and is struggling to find the correct answer. They are advised to start over from the beginning by normalizing the given state. The person then realizes their mistake and is able to find the solution with help.
  • #1
Shivy G
13
0

Homework Statement



upload_2016-2-29_18-55-54.png


The problem is given above. I am struggling on the first two parts, where I am tasked with finding gamma and beta.

Homework Equations



For spin one half states in arbitrary directions, I know that psi = a*|n;+> + b*|n;-> .

|n;+> = cos(theta/2)|+> +sin(theta/2)*ei*phi|->

|n;-> = -sin(theta/2)e-i*phi|+> + cos(theta/2)|->

The Attempt at a Solution



I have attached my attempt at a solution. I am not sure what I am doing wrong at this point. Any help for the problem would be greatly appreciated :)
 

Attachments

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  • #2
There are multiple mistakes in your calculation. I would suggest that you start over again from the first step by first normalizing the given ##|\psi\rangle##.
 
  • #3
I ended up getting the solution. I was making a mistake by splitting it up into |n;+> and |n;->. Instead, I factored out a phase and then normalized the whole thing. The answer came fairly quickly from there. Thanks.
 

Related to Question on spin 1/2 states in arbitrary direction

1. What is a spin 1/2 state?

A spin 1/2 state refers to a quantum mechanical state of a particle with a spin quantum number of 1/2. This means that the particle has two possible spin orientations, either up or down, and can be in a superposition of both states.

2. What does "arbitrary direction" mean in spin 1/2 states?

"Arbitrary direction" refers to any direction in three-dimensional space. In the context of spin 1/2 states, it means that the particle's spin can be measured in any direction, not just along a specific axis.

3. How are spin 1/2 states described mathematically?

Spin 1/2 states are described using mathematical objects called spinors, which are complex numbers arranged in a specific way. These spinors can be used to calculate the probabilities of measuring a particular spin orientation in a given direction.

4. What is the significance of spin 1/2 states in quantum mechanics?

Spin 1/2 states play a crucial role in quantum mechanics and are fundamental to our understanding of the behavior of particles at the subatomic level. They have important applications in areas such as quantum computing, particle physics, and quantum information theory.

5. How are spin 1/2 states experimentally observed?

Spin 1/2 states can be observed through experiments such as Stern-Gerlach experiments, where particles with a spin of 1/2 are passed through a magnetic field and their spin orientations are measured. Other techniques, such as nuclear magnetic resonance (NMR) spectroscopy, can also be used to study spin 1/2 states.

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