counterterms

“Even the supersymmetry is no problem: the lattice breaks it, but because of the superrenormalizability one can calculate explicitly the counterterms needed to restore the symmetry in the continuum limit, and so all the predictions of AdS/CFT can be checked algorithmically.”

Guest Blogger: Joe Polchinski on the String Debates

“I have given a specific argument why we are well within the domain of applicability of Wilson: there are 1+1 and 2+1 dimensional versions of AdS/CFT, which are also constructions of quantum gravity, and for which the gauge theory is super-renormalizable (and there are no chiral fermions): the counterterms needed to reach the supersymmetric continuum limit can be calculated in closed form - thus there is an algorithmic definition of the gauge theory side of the duality.”

Guest Post: Joe Polchinski on Science or Sociology?

“For one thing, anyone can dive in; you don’t need to be an expert on twistor space, or two-loop counterterms, or BRST invariance in order to pontificate about the conditions under which life could exist if the laws of physics were very different.”

Ask a String Theorist! Or an Atomic Physicist.