161 citations · 685 across the 15 of their papers we have counts for
3 papers · 1 filter
Supersymmetric k-defects
Michael Koehn, Mark Trodden
In supersymmetric theories, topological defects can have nontrivial behaviors determined purely by whether or not supersymmetry is restored in the defect core. A well-known example…
Non-Singular Bouncing Cosmology: Consistency of the Effective Description
Michael Koehn, Jean-Luc Lehners, Burt Ovrut
We explicitly confirm that spatially flat non-singular bouncing cosmologies make sense as effective theories. The presence of a non-singular bounce in a spatially flat universe imp…
Towards a Solution of the Negative Mode Problem in Quantum Tunnelling with Gravity
Michael Koehn, George Lavrelashvili, Jean-Luc Lehners
In the absence of gravity, one can prove that tunnelling instantons exhibit exactly one negative mode in their spectrum of fluctuations. It is precisely the existence of this tunne…