In Arxiv today: Supersymmetry breaking

Today there are some interesting papers in arxiv, although not so many as the previous Monday. Some of them are purely mathematical, or concern formal aspects.

I like formal aspects, and mathematics, but because I had some leaks on recent phenomenology I am provisionally interested in more mundane topics. One key aspect in phenomenology is supersymmetry breaking. To begin with the MSSM (minimal supersymmetricla standard model) only can get supersymmetry breaking by means of soft terms which are outside the model itself. These terms must arise by some method that generates them.

The older studied method is gravity mediates supersymmetry breaking. There the breaking os supersymmetry happens at high energies,because of gravity related mechanisms and gets communicate to the MSSM by means of moduli (that is, scalar neutral fields).

Another mechanism is gauge mediate supersymmetry breaking. There supersymmetry breaking happens in a hidden sector (in heterotic E8xE8 string theory typically the "other" E8) and gets transmitted to the visible sector by some gauge field.

Still another method is AMSB (anomaly mediatesd smmetry breaking). And there are a few more. All of theme have their own advantages and problems.

Instead of trying to give details here I will refer the readers to this paper A Comparison of Supersymmetry Breaking and Mediation Mechanisms by S.P. de Alwis where a review of the topic is made. It also includes many links to the key papers in the subject so it is a perfect way to get a proper guide to the subject if because of some reason you can´t or want to read a whole book about the subject. The review also gives references of string theoretical realizations of the mechanism, which is a great plus.

Sparticles

Supersymmetry is easy, isn't it?. I have posted (in spanish) a brief introduction to the subject. And I'll make more posts abut it. I am almost sure that everyone who has passed a course in QFT can understand the basics of supersymmetry.

After all, you have a superpartner for every particle, that has opposite statistic. You have funny names for the superpartnerts. The partner of the electron is the slectron, the quark has the squark, etc. And for bosonoics fields the thing is easy also. To the photon corresponds the photino, to the gluons the gluino, to the higgs the higssino, etc.

Well, them if you remember that for every broken global symmetry there is an associated particle, the goldstone boson them you know what a goldstino is. Isn't it?

Well, if you read the book that gives title to the entry(the full title is theory and phenomenology of sparticles) you will realize that maybe the goldstino could not be exactly what you think.

And, of course, you will learn a lot more about phenomenology of N=1 supersymmetry in 4 dimensiones. That includes the MSSM, cosmology of supersymmetry models, etc, etc. The books is from 2004 (reprinted in 2007) so it is, I guess, terribly outdated. I find it a lot better option that the,somewhat similar in it's purpose, book of Michel Dine (supersymmetry and superstrings). Ok, this book doesn't cover superstring, and it has many more pages. But with the actual trend of growing interest in phenomenology, motivated by the dark matter experiments, and the beginning of operation of the LHC it looks as a good reference book to get good info about the characteristics of neutralino, methods of supersymmetry breaking or whatever.

P.S. I'll try o update the previous posts, as promised, as soon as possible.