32 citations · 74 across the 7 of their papers we have counts for
7 papers
Landau Singularities of the 7-Point Ziggurat II
Luke Lippstreu, Marcus Spradlin, Akshay Yelleshpur Srikant +1
We solve the Landau equations to find the singularities of nine three-loop 7-point graphs that arise as relaxations of the graph studied in arXiv:2211.16425. Along the way we estab…
Landau Singularities of the 7-Point Ziggurat I
Luke Lippstreu, Marcus Spradlin, Anastasia Volovich
We compute the leading (first-type Landau) singularities of a certain four-loop 7-point graph that is related to the 7-point ``ziggurat'' graph by the graphical moves familiar from…
Angular momentum of the asymptotic electromagnetic field in the classical scattering of charged particles
Rishabh Bhardwaj, Luke Lippstreu
We compute the angular momentum of the electromagnetic field on a late time Cauchy surface with an arbitrary constant normal vector relevant for the classical scattering of charged…
Loop-level gluon OPEs in celestial holography
Rishabh Bhardwaj, Luke Lippstreu, Lecheng Ren +3
We compute one-loop corrections to the OPE of gluons in the celestial conformal field theory corresponding to Yang-Mills coupled to arbitrary matter. We exploit universal hard/soft…
Four-point correlators of light-ray operators in CCFT
Yangrui Hu, Luke Lippstreu, Marcus Spradlin +2
We compute the four-point correlator of two gluon light-ray operators and two gluon primaries from the four-gluon celestial amplitude in signature spacetime. The correlator…
Zwanziger's pairwise little group on the celestial sphere
Luke Lippstreu
We generalize Zwanziger's pairwise little group to include a boost subgroup. We do so by working in the celestial sphere representation of scattering amplitudes. We propose that du…
Weak Separation, Positivity and Extremal Yangian Invariants
Luke Lippstreu, Jorge Mago, Marcus Spradlin +1
We classify all positive n-particle N^kMHV Yangian invariants in N=4 Yang-Mills theory with n=5k, which we call extremal because none exist for n>5k. We show that this problem is e…