Re: [Phys-L] Special Relativity for QFT

[David Craig <craigda@lemoyne.edu>]

> On Jul 20, 2018, at 9:00 AM, phys-l-request@mail.phys-l.org wrote:
> From: John Denker <jsd@av8n.com>
>
> On 07/20/2018 12:02 AM, David Craig wrote:
> > students need to be able to recognize the equations they will find in field theory books, the majority of which contain many expressions of the form x^\mu=\Lambda^\mu_\nu x^\nu and so forth.
>
> It might be worth revising that to emphasize that the x-components on the LHS are not the same as the x-components on the RHS ... even though the abstract x-vector has the same physical meaning.

The lack of an additional decoration on the LHS was just a consequence of clicking “send” a little too quickly.

FWIW, I’ve always liked Schutz’s approach to this, decorating the index and not the vector to emphasize that one is writing components of the same vector in a different basis.


David Craig


<http://web.lemoyne.edu/~craigda/>