http://upload.wikimedia.org/wikipedia/commons/1/1f/Feynmann_Diagram_Gluon_Radiation.svg
Why is the arrow of the positron not upwards?
$\begingroup$
$\endgroup$
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
3
The arrow is related to the flow of charge, not the direction of motion. So for antimatter they go the opposite way.
Or as some are fond of saying, the positron is like an electron moving backwards in time.
-
$\begingroup$ Thanks! But moving backwards in time? This is a joke right? $\endgroup$– kameCommented Feb 21, 2011 at 15:06
-
2$\begingroup$ Not a joke at all. This isn't a joke either: en.wikipedia.org/wiki/One-electron_universe $\endgroup$ Commented Feb 21, 2011 at 17:00
-
2$\begingroup$ @Keenan: ''moving backward in time'' is a relic from the times of the dirac sea. But in quantum field theory, all particles move forward in time (i.e., the momentum vector has a positive 0-component). $\endgroup$ Commented Mar 25, 2012 at 19:43