I am giving a short talk on supersymmetry for my intro to high energy class, but I do not have the time to read an entire book on the subject. Most resources I have found go into much more depth than I need, but these seem to be the only resources. Can anyone help me with the basics conceptually?
The Attempt at a Solution
Here's what I already know:
SUSY attempts to explain certain problems with the standard model, namely the fact that the forces do not have the same strengths at any energy, and the fact that the masses of the particles, or more directly the Higgs' boson, are far different from their theoretical values (due to renormalization problems of the Higgs mass).
The fact that fermions could be related to bosons is due to the fact that when the corrections to the Higgs mass are calculated, the divergent quantities seem to cancel if both fermionic as well as bosonic contributions to the correction are included. This means that the Higgs' mass is a result of its fermionic nature as well as its bosonic nature. Since other particle masses are calculated from the Higgs mass, all particles should share this symmetry.
My questions are:
Why does this imply that no known particles are superpartners of each other (e.g. why are the known fermions not superpartners for any of the known bosons)?
How does this affect the unification of the forces? I read somewhere that without SUSY, the forces never actually converge to a single energy, but with it they do. I do not understand this.
Finally, how does the prediction of the spin-2 graviton come about?
I understand that this is a very complex topic and that a lot of intense group theory is needed to fully understand it, but any help would be extremely appreciated. Thanks so much in advance!