Problem with anticommutation of spinors

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In summary: Therefore, the ordering reversion does not apply and we do not get a minus sign. In summary, the minus sign in the first equation comes from the anticommuting nature of Majorana spinors, while the absence of a minus sign in the second equation is due to the fact that we are taking the complex conjugate instead of the transpose.
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ansgar
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In e.g. Burgess and Moore - standard model a primer

it is stated that for two spinors (majorana)

[tex] \bar{\psi_1}\psi_2 = (\bar{\psi_1}\psi_2)^T = - \psi_2^T \bar{\psi_1}^T [/tex]

since the spinors are anticommuting objects, thus ordering reversion gives -1

but they also state that

[tex] (\psi_1^\dagger\psi_2 )^* = (\psi_1^\dagger \psi_2)^\dagger = \psi_2^\dagger \psi_1 [/tex]

i.e. "without a minus sign" (explicity written in text)

I am SOOO confused, how how how can this be consistent??

best regards

37 views so far, come on I know that you can help me :)
 
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The minus sign comes from the fact that the Majorana spinors are anticommuting objects. That is, for any two Majorana spinors, a and b, we have that a * b = -b * a. This means that when we take the transpose of a product of two Majorana spinors, we get the same result as taking the reverse order of the product, but with a minus sign. So, the minus sign in the first equation comes from the fact that \bar{\psi_1}\psi_2 is the transpose of (\bar{\psi_1}\psi_2)^T. In the second equation, however, there is no minus sign because we are not taking the transpose of the product. We are simply taking the complex conjugate of it, which does not change the order of the product.
 

FAQ: Problem with anticommutation of spinors

1. What is the problem with anticommutation of spinors?

The problem with anticommutation of spinors is that it leads to inconsistencies in the mathematical equations used to describe the behavior of spinors in quantum mechanics. This can make it difficult to accurately predict and understand the behavior of particles at the subatomic level.

2. Why is the anticommutation of spinors important in quantum mechanics?

The anticommutation of spinors is important because it is a fundamental property of fermions, which are particles that make up matter. This property is necessary for accurately describing the behavior of fermions in quantum mechanics, such as their spin and angular momentum.

3. How does the anticommutation of spinors affect quantum computing?

The anticommutation of spinors is a crucial aspect of quantum computing, as it allows for the creation of quantum bits (qubits) which can exist in multiple states simultaneously. This property is essential for the efficient and powerful processing capabilities of quantum computers.

4. Can the problem with anticommutation of spinors be resolved?

Currently, there is no definitive solution to the problem with anticommutation of spinors. However, there are ongoing research efforts to find ways to work around this issue and develop more consistent mathematical models for spinors in quantum mechanics.

5. How do scientists continue to study and understand the problem with anticommutation of spinors?

Scientists use a combination of theoretical models and experimental data to study and understand the problem with anticommutation of spinors. They also collaborate and share their findings with other experts in the field to further advance our understanding of this complex issue.

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