Hello Coin,
this way of suggesting things as natural look to me quite antropic...
In that case, why not invoking some underlying group theory telling us how many families we should expect, it will be as natural as infinite.
Hello,
you can just look at existing pdg limits :
m_nu < 2 eV
If there is a neutral heavy leptons
m > 90.3 GeV if Dirac
m > 80.5 GeV if Majorana
So if there is a standard 4th generation neutrino, there is a big mass gap between 3rd and 4th generation.
Then, that could be sterile...
Hello,
I have read in a susy introduction paper that if we call Q the charge which links fermions and bosons, then we have the following anticommutation relation :
{Q_a, Q_b} = 2 sigma_ab P
where P is 4-momentum.
So, is this relation only due to Coleman-Mandula theorem which force the...
Hello,
Yes, I would be glad to know how does susy appear in string theory ? Is it a consequence of strings or extra-dimensions (which can be wo strings) or both or something else ?
Thanks.
All big accelerators from the last 15years (like LEP, Tevatron) could/can discover SUSY. But as they haven't observed any stricking excess, they just set low mass limits.
In principle the advantages of LHC wrt Tevatron are both energy and luminosity, but you have to be aware that even LHC...