Hi guys. I have been a mathematical physicist and have recently been taking great interest in theoretical particle physics. With some effort I can do calculations in the International System of Units (SI) with complete success if I focus very carefully.(adsbygoogle = window.adsbygoogle || []).push({});

With the particle physics natural units which have h/2π = c = 1 , I have recently found myself rather embarrassed.

I want to use g = e/sinθ_{W}and g' = e/cosθ_{W}in calculations and when I came to convert e from coulombs to natural units, I really did not know where to start. These natural units seem to be really easy for you guys.

Read somewhere that converting from these natural units is pretty easy; the prescription seems to be to know what is the particular physical quantity that you are to calculate, such as cross-section, and you simply write out what should be its dimensions in the usual MLT format and then say 'what's missing, given what's in this formula that will give it the right dimensions?' and you simply multiply by the appropriate power of h/2π and c (powers may be negative or fractional), and it is not possible to go wrong with this prescription. This seems fair enough. First of all, have I got this right?

Secondly, would be really grateful if someone could please show me how to calculate g = e/sinθ and g' = e/cosθ in these natural units as well as the formula for the mass of the W which is M_{W}= (e^{2}/4)√2G_{F}sin^{2}θ_{W}also in these natural units.

Thanks for your help. I think your reply will really help anyone else just starting out on natural units.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Getting natural units right in particle physics

**Physics Forums | Science Articles, Homework Help, Discussion**