- #1

- 16

- 0

I've just read the statement that a matrix that commutes with all four gamma matrices / Dirac matrices has to be a multiple of the identity. I don't see that; can anyone tell me why this is true?

Thanks in advance

- Thread starter Ameno
- Start date

- #1

- 16

- 0

I've just read the statement that a matrix that commutes with all four gamma matrices / Dirac matrices has to be a multiple of the identity. I don't see that; can anyone tell me why this is true?

Thanks in advance

- #2

Physics Monkey

Science Advisor

Homework Helper

- 1,363

- 34

If you can decide:

1) that this basis is complete for 4x4 matrices

2) that nothing in this basis besides 1 commutes with all the [tex] \gamma [/tex]

then you will have what you want.

- #3

- 16

- 0

OK, I also had this answer in mind (which I already found), but I thought that there is a simpler answer because this statement appeared at a point in the script where that basis has not yet been introduced. Perhaps I'll find a simpler answer, but I'm also fine with this one. At least I see that it's not

- #4

Physics Monkey

Science Advisor

Homework Helper

- 1,363

- 34

- #5

- 16

- 0

- Last Post

- Replies
- 4

- Views
- 2K

- Last Post

- Replies
- 2

- Views
- 3K

- Replies
- 4

- Views
- 3K

- Last Post

- Replies
- 12

- Views
- 2K

- Last Post

- Replies
- 14

- Views
- 13K

- Last Post

- Replies
- 4

- Views
- 485

- Last Post

- Replies
- 2

- Views
- 3K

- Last Post

- Replies
- 7

- Views
- 2K

- Last Post

- Replies
- 1

- Views
- 2K

- Last Post

- Replies
- 0

- Views
- 2K