Recent content by petergreat

I figured out myself. One had to introduce a \xi term -\frac 1 {2\xi} (n.A)^2 and work out the axial gauge gluon propagator for general values of \xi, even though we're only interested in the unitary limit \xi\rightarrow 0. The graphical ward identities are almost the same as the counterpart...

This post should be moved to "Special & General Relativity" subforum. It's a simple exercise in special relativity, and doesn't really require knowledge of particle physics.

How do (offshell) QCD ward identities look like in the axial gauge? How to derive them? The standard treatment of ward identities uses BRST symmetry in the covariant gauge. I don't know where I can read about the axial gauge version of the ward identities.

Can anyone who have IE9 installed check whether the file ieuser.exe is one of the installed files? This would be really helpful!

I can open and run IE 9 just fine, but again in Windows Task Manager I don't see the process ieuser.exe. Unless this file is no longer present in the latest version of IE 9, I smell something suspicious.

I'm using Windows Vista SP2 and IE 9. An anti-spyware program alerted me that ieuser.exe, a crucial IE component, is missing. I checked C:\Program Files\Internet Explorer, and indeed there were several .exe files but no ieuser.exe. First question, is this file present in version 9 of IE...

You're welcome! The last step will become trivial after you've learned Fourier transform. Basically, it says that the Fourier transform of the constant function is the delta function. You need to know Fourier transform and complex analysis before tackling QFT.

By \delta I mean \delta^{(3)}.

\int\frac{d^{3}pd^{3}p^{\prime}}{\left( 2\pi\right)^{6}}\frac{-i}{2}\sqrt{\frac{\omega_{p^{\prime}}}{\omega_{p}}}\left( \left[ a_{-\textbf{p}}^{\dagger},a_{\textbf{p}^{'}}\right] -\left[ a_{\textbf{p}},a_{-\textbf{p}^{'}}^{\dagger}\right]\right) e^{i\left(...

What's the main production channel of B-mesons at the LHC? Gluon-Gluon fusion?

This particle has a mass of only 10.5 GeV. Why has it eluded LEP and Tevatron? What makes LHC suitable for its discovery? If a future 500 GeV International Linear Collider is built, will it be capable of studying this particle?

I think I more or less understand what the authors are doing now. The renormalization scale \mu_R is used for dimensional regularization of UV divergence, and produces the factor (4\pi \mu_R^2/Q^2)^\epsilon. On the other hand, the factorization scale \mu_F (which is probably used in a...

It's this paper about Higgs cross section. http://arxiv.org/abs/hep-ph/0306211 The formula is Eqn. (1) on Page 2. (My posting above has changed it into a generic form, but the spirit is the same.) On Page 4 the analytical NLO expressions are given.

Let me make my question more precise. I encountered a formula of this form \sigma(Q^2)=\sum_{a,b} \int_0^1 \frac {dx_1}{x_1} \frac {dx_2}{x_2} f_a (x_1,\mu_F^2) f_b(x_2,\mu_F^2) G_{ab}(x_1 x_2; \alpha_S(\mu_R^2), Q^2/\mu_R^2; Q^2/\mu_F^2), where Q^2 is the experimental energy scale, \mu_F is the...

You can't. The proton mass has little to do with the Higgs. Therefore its resistance to acceleration has little to do with the Higgs. No one has claimed so. A Lorentz transformation never turns a non-rotating body into a rotating body (though it can affect the linear velocity). So Lorentz...