85 citations · 200 across the 14 of their papers we have counts for
14 papers
Enumeration of multi-rooted plane trees
Anwar Al Ghabra, K. Gopala Krishna, Patrick Labelle +1
We give closed form expressions for the numbers of multi-rooted plane trees with specified degrees of root vertices. This results in an infinite number of integer sequences some of…
Revisiting wormhole energy conditions in Riemann-Cartan spacetimes and under Weyl transformations
Fayçal Hammad, Étienne Massé, Patrick Labelle
We show that the violation of the null energy condition by matter, required by traversable wormholes, can be removed in spacetimes with torsion. In addition, we show that this viol…
Black hole mechanics and thermodynamics in the light of Weyl transformations
Fayçal Hammad, Étienne Massé, Patrick Labelle
The fate of black hole thermodynamics under Weyl transformations is investigated by going back to the laws of black hole mechanics. It is shown that the transformed surface gravity…
Feynman diagrams, ribbon graphs, and topological recursion of Eynard-Orantin
K. Gopala Krishna, Patrick Labelle, Vasilisa Shramchenko
We consider two seemingly unrelated problems, the calculation of the WKB expansion of the harmonic oscillator wave functions and the counting the number of Feynman diagrams in QED…
Enumeration of N-rooted maps using quantum field theory
K. Krishna Gopala, Patrick Labelle, Vasilisa Shramchenko
A one-to-one correspondence is proved between the N-rooted ribbon graphs, or maps, with e edges and the (e-N+1)-loop Feynman diagrams of a certain quantum field theory. This result…
Topological recursion of Eynard-Orantin and the Harmonic Oscillator
Miguel Cutimanco, Patrick Labelle, Vasilisa Shramchenko
We apply the Chekhov-Eynard-Orantin topological recursion to the curve corresponding to the quantum harmonic oscillator and demonstrate that the result is equivalent to the WKB wav…