Speaker
Description
No evidence of "new physics" in general and supersymmetry in
particular was found so far by LHC experiments, and this
situation has led some voices in the physics community to call
for the abandonment of the "naturalness" criterion, while other
scientists have felt the need to break a lance in its defense by
claiming that, at least in some sense, it has already led to
successes and therefore should not be dismissed too quickly, but
rather only reflected or reshaped to fit new needs. In our paper
we will argue that present pro-or-contra naturalness debates miss
the fundamental point that naturalness, despite contrary claims,
is essentially a very hazily defined, in a sense even mythical
notion which, in the course of more than four decades, has been
steadily, and often not coherently, shaped by its interplay with
different branches of model-building in high-energy physics and
cosmology on the one side, and new incoming experimental results
on the other. A particularly important factor in this
constellation, albeit by far not the only one, was the rise of
supersymmetry from the 1980s onward. In our paper we will
endeavor to clear up some of the physical and philosophical haze
by taking a closer look back at the encounter and interplay
between naturalness and supersymmetry, starting from the 1970s,
when the search for "natural" particle models and "natural"
solutions to the hierarchy problem of Grand Unified Theories
began, to the rise to prominence of the "unnatural" Higgs mass
divergences, up to and beyond the time when a facet of
naturalness was co-opted as a criterion for supersymmetric
model-building. In doing this, we aim to bring to light how
naturalness belongs to a long tradition of present and past
physical and philosophical criteria for effectively guiding
theoretical reflection and experimental practice in fundamental
research.
