Abstract: In this talk, I will consider the interface separating and
spins in the critical planar Ising model with Dobrushin boundary conditions perturbed by an external magnetic field. I will prove that this interface has a scaling limit. This result holds when the Ising model is defined on a bounded and simply connected subgraph of
, with
. I will show that if the scaling of the external field is of order
, then, as
, the interface converges in law to a random curve whose law is conformally covariant and absolutely continuous with respect to SLE
. This limiting law is a massive version of SLE
in the sense of Makarov and Smirnov and I will give an explicit expression for its Radon-Nikodym derivative with respect to SLE
. I will also prove that if the scaling of the external field is of order
with
, then the interface converges in law to SLE
. In contrast, I will show that if the scaling of the external field is of order
with
, then the interface degenerates to a boundary arc.
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