Solving Spinor Problems: Working Through (3.75), (3.77)-(3.79) in Google Book

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The derivations for equations (3.78) and (3.79) follow similar steps, utilizing the properties and definitions of the charge conjugation matrix and gamma matrices.I hope this summary has helped clarify the concepts and steps involved in these spinor calculations. If you have any further questions or concerns, please do not hesitate to ask. Keep up the good work in your studies!In summary, the conversation discusses some spinor calculations in a book and addresses two questions about the significance of a statement related to chirality and the derivation of equations (3.77)-(3.79). The first question is answered by explaining the relationship between certain values of D and the conservation of chirality in spinors.
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latentcorpse
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I'm working through some spinor calculations in the following book:
http://books.google.co.uk/books?id=...ame as complex conjugate for a scalar&f=false

On p54 and p55, I have a few things that are troubling me:

(i) Underneath (3.75), he notes that for D=2,3,4,10,11, we have -t_0t_1=+1 (see Table 3.1 for t_r values) and so the Majorana conjugate of the charge conjugate will be equal to the Dirac adjoint of the spinor. What is the significance of this statement?

(ii) How do we derive (3.77)-(3.79)? I cannot make much headway.

For example, my attempt to prove (3.77) is as follows:
[tex] (\gamma^\mu)^C = B^{-1} (\gamma^\mu)^C B [/tex]
[tex] = i t_0 \gamma^0 C^{-1} (\gamma^\mu)^* i t_0 C \gamma^0 [/tex]
[tex] =i^2 t_0^2 \gamma^0 C^{-1} (\gamma^\mu)^* C \gamma^0 [/tex]
[tex] =-\gamma^0 C^{-1} (\gamma^\mu)^* C \gamma^0 [/tex]
where we've used [tex]B=it_0 C \gamma^0 \Rightarrow B^{-1}=-i t_0 (\gamma^0)^{-1} C^{-1} = i t_0 \gamma^0 C^{-1}[/tex]

Now the problem is that we have something involve the complex conjugate of the gamma matrix. If we had something involving the charge conjugate then we could substitute from (3.45) and be finished. I cannot see how to get from here to what they have in (3.77)

Thanks.
 
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Thank you for sharing your concerns and questions regarding the spinor calculations in the book you are working through. I am happy to assist you in understanding these concepts.

To address your first question, the statement about -t_0t_1=+1 for certain values of D is significant because it is related to the property of chirality in spinors. Chirality refers to a particle's tendency to move in a particular direction, either left or right. In the context of spinors, this means that the spinor will have a specific handedness or orientation. The values of D mentioned in the book correspond to the dimensions of spacetime where chirality is conserved, meaning that the handedness of the spinor is preserved in interactions. This has important implications in particle physics and can help identify the types of interactions that are possible.

Moving on to your second question, the derivation of equations (3.77)-(3.79) involves some algebraic manipulations and properties of the gamma matrices. I will not go through the entire derivation, but I will provide some key steps that may help you in understanding the process.

First, it is important to note that the charge conjugate of a gamma matrix can be written as a complex conjugate of the gamma matrix multiplied by the charge conjugation matrix C. This is given by equation (3.45) in the book.

Next, using this property, we can rewrite the expression for (\gamma^\mu)^C as (\gamma^\mu)^C = (\gamma^\mu)^* C. Then, using the fact that (\gamma^\mu)^* C = -C^{-1} (\gamma^\mu)^T C, we can simplify the expression further.

Now, using the properties of the charge conjugation matrix C, we can show that C^{-1} (\gamma^\mu)^T C = -i t_0 C^{-1} (\gamma^\mu)^* C \gamma^0. This is due to the fact that C^{-1} = -i t_0 \gamma^0, as shown in the book.

Finally, substituting this expression back into our original equation, we get (\gamma^\mu)^C = -i t_0 C^{-1} (\gamma^\mu)^* C \gamma^0 \gamma^0 = -i t_0 (\gamma^\mu)^* C \gamma^0, which is equivalent
 

Related to Solving Spinor Problems: Working Through (3.75), (3.77)-(3.79) in Google Book

1. What are spinor problems?

Spinor problems are mathematical problems that involve the use of spinors, which are mathematical objects used to represent spin in quantum mechanics.

2. What is the significance of solving spinor problems?

Solving spinor problems allows us to better understand the behavior of particles with spin in quantum mechanics and make predictions about their properties and interactions.

3. What is the book "Working Through (3.75), (3.77)-(3.79) in Google Book" about?

This book is a guide that walks through the process of solving specific spinor problems, using equations (3.75), (3.77)-(3.79) as examples.

4. Are there any prerequisites for understanding this book?

Yes, a basic understanding of quantum mechanics and spinors is necessary to fully understand and apply the concepts in this book.

5. Can this book be used for self-study or is it meant for classroom use?

This book can be used for both self-study and classroom use. It provides clear explanations and step-by-step solutions, making it accessible for individual study, but it can also be used as a supplement to a course on quantum mechanics or spinors.

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