Recent content by MManuel Abad

Wooow! Thank you so much all, this was so complete!

What about terms with coefficients d^{ijk} d^{klm}? Wouldn't they be able to produce \Phi^4 terms as well? Or does this contraction also have an expression in terms of \delta^{ij}'s? If that is the case, do you happen to know it?

Hello, people. I'm studying (as an exercise) the breaking of an SU(3) gauge group to SU(2) x U(1) via a Higgs mechanism. The scalar responsible for the breaking is \Phi, who transforms under the adjoint representation of SU(3) (an octet). First of all I want to construct the most general...

Thanks a lot to everyone for your suggestions!

Hello, everybody: I was wondering if you knew if there is a book, journal, webpage or a compendium of some sort in which different and diverse curious common and uncommon natural phenomena are explained with physics (preferably with math involved). For example, a place where to look if I'm...

That'll do! Thanks! It didn't occur to me to look for the size of the extra dimension... Cheers

Muons and tauons as KK modes?? Hello, everybody: I have (what I think is) a silly question. We all know that μ and τ particles are just as electrons, but with larger mass. Could it be that they are heavier Kaluza-Klein modes of the e in a higher dimensional theory, where the extra dimension...

Oh! These orthonormal frames are simply the tetrads, aren't they? So no, instead of asking the fields to be representations of SU(2)xSU(2), we ask their contractions with the Vierbein to be irreps of this group. Is this correct? Thankyou!

Hello, people: I've been wondering about the definition of Quantum Fields in Curved Space-times (CS). I know that, in flat space-time (Minkowski), the fields are defined as irreducible representations of the universal covering group SU(2)xSU(2) of SO(4) (which is basically the Lorentz group...

Yes, Ben Niehoff. Actually, in the atyy's first reference, they begin with that very same parametrization :D Thanks a lot. Thanks for the book, atyy

Wow, thanks, atyy. It appears I did it in another way: in the pdf file you gave me they first obtain the metric in the last form I wrote, and after that in the hyperbolic-functions form. I did it the other way-around :P I can see how they obtain the other forms of the metric, that was really...

Wow, man, that was really useful! I think I understand now how to go from the hyperboloid description to the AdS metric as Witten writes it. Nevertheless I still do not figure out how to go from this (Witten's) metric to one of the former ones. It took me a while, but now I think I get it: The...

Hello, everybody. I have some doubts I hope you can answer: I have read that the n+1-dimensional Anti-de Sitter (from now on AdS_{n+1}) line element is given, in some coordinates, by: ds^{2}=\frac{r^{2}}{L^{2}}[-dt^{2}+\sum\limits_{i=1}^{n-1}(dx^{i})^{2}]+\frac{L^{2}}{r^{2}}dr^{2} This can be...

Wow! Thank you very much! Those were actually very good and complete explanations! You both complemented the whole point of my thread! That was very useful! This forum always gives me what I want, so I thank you both again! Greetings from Mexico!

Hi there: I was just searching about Gauge theories and stuff and I find it very confusing. My major complication is the classification. I'd like you to tell me some definitions and construct a "family tree". I guess it goes something like this: Gauge Theory: A Field Theory in which the...