Four Interactions
You may be, at first, surprised, that gravity is the weakest interaction. However, when you drop
something on the floor, it is gravity that accelerates it, but electromagnetic interactions between the electrons and
protons in the object and in the floor that makes the object come to rest!
Feynman´s lectures on Physics, Book 2, starts with a wonderful
description of similarities and differences between
electromagnetism and gravity. Read it, read it again - make it part of your way
of viewing the world!
| Interaction | Mediated by | Responsible for ... | Symmetries
|
| Strong |
Gluons | Interaction between quarks in nucleons and
nuclei
|
| Electromagnetic | Photons | Chemistry, Biology..
|
| Weak | W and Z bosons | radioactivity | Violates mirror and time reversal symmetries
|
|---|
| Gravity | "gravitons" | Interactions between stars and galaxies ...
|
Which of the interactions do you expect to be involved in the
- Colours in a rainbow
- Energy production in the sun
- Tidal waves
- Radiation after Chernobyl
- Photosynthesis
- Colour of a sodium streetlamp
- Motion of the earth around the sun
Or try the
Quiz from CPEP.
?
(From
"The Particle Adventure")
http://fy.chalmers.se/~f3aamp/VVV/four.html
Ann-Marie Pendrill, Fysik,
GU /
CTH, 1997-05-31