Mathematical Quantum Field Theory - Propagators - Comments

[Urs Schreiber]

Greg Bernhardt submitted a new PF Insights post

Mathematical Quantum Field Theory - Propagators

Continue reading the Original PF Insights Post.

 

[A. Neumaier]

- ''the the Feynman propagator'' has a the too much.
- The table above Definition 9.2 is unbalanced.
- \widecheck is undefined
- UV divergences are mentioned repeatedly but each time only in passing without any explanation of how it should be related to the wave front set.

 

[Urs Schreiber]

Thanks for these alerts!

UV divergences are mentioned repeatedly but each time only in passing without any explanation of how it should be related to the wave front set.

I had a brief comment on this, but have made it more prominent now: new remark 9.27.

- \widecheck is undefined

I had fixed this before, but apparently it came back with my previous update. The trouble is that I have "widecheck" in my source code for the inverse Fourier transform, but the MathJax here does not seem to know this command. As a hack, I have replaced it by "widetilde", but this is sub-optimal. If you or anyone else reading here has a suggestion for how to typeset this with MathJax, please let me know.

The table above Definition 9.2 is unbalanced.

I have fixed this by hand now, but I don't understand why the converter produced this issue in the first place. My source code is correct at this point. So if I forget about fixing this by hand again next time that I make an update, the problem might reappear.

 

[A. Neumaier]

new remark 9.27.

dtail $\to$ detail

 

[Urs Schreiber]

dtail $\to$ detail

Thanks! Fixed now.

 

[vanhees71]

Thanks for these alerts!
I had a brief comment on this, but have made it more prominent now: new remark 9.27.
I had fixed this before, but apparently it came back with my previous update. The trouble is that I have "widecheck" in my source code for the inverse Fourier transform, but the MathJax here does not seem to know this command. As a hack, I have replaced it by "widetilde", but this is sub-optimal. If you or anyone else reading here has a suggestion for how to typeset this with MathJax, please let me know.
I have fixed this by hand now, but I don't understand why the converter produced this issue in the first place. My source code is correct at this point. So if I forget about fixing this by hand again next time that I make an update, the problem might reappear.

You can define macros in mathJax as in LaTeX, using the usual \newcommand command within a math environment. The only drawback is that you get some empty lines, where you place this. I couldn't figure out how to give plain html commands yet. Using plain html you can avoid the blank lines by setting the \newcommand definitions within a paragraph cf. <p style="display:none">...</p>.

 

[Urs Schreiber]

You can define macros in mathJax as in LaTeX, using the usual \newcommand command within a math environment.

Thanks, that's useful to know. Do you think this gives a way to produce a "widecheck" here on PF?