  We explore some curiosities in 4d susy RG flows. One issue is that the
compelling candidate a-function, from a-maximization with Lagrange multipliers,
has a `strange branch," with reversed RG flow properties, monotonically
increasing instead of decreasing. The branch flip to the strange branch occurs
where a double-trace deformation Delta W=O ^2 passes through marginality,
reminiscent of the condition for the chiral symmetry breaking, out of the
conformal window transition in non-susy gauge theories. The second issue arises
from Higgsing vevs for IR-free fields, which sometimes superficially violate
the a-theorem. The resolution is that some vevs trigger marginal or irrelevant
interactions, leading to Delta a=0 and decoupled dilaton on a subspace of the
moduli space of vacua. This is contrary to classical intuition about Higgsing.
This phenomenon often (but not always) correlates with negative R-charge for
the Higgsing chiral operator.

High Energy Physics - Theory