Alladi Ramakrishnan Hall

Supersymmetry: Aspirations and Prospects

Xerxes Tata

University of Hawaii

The hypothesis of weak scale supersymmetry ameliorates the gauge hierarchy problem, yields gauge couplings consistent with grand unification, and when augmented by R-parity conservation, provides natural candidates for the observed dark matter (DM).
However, experiments at the LHC have not turned up any direct evidence for the existence of superpartners, seemingly in conflict with early expectations that suggested that superymmetry would be revealed even at LEP2 or the Tevatron. We critically re-evaluate the arguments that led to these expectations and conclude that phenomenologically viable SUSY spectra with no worse that a few percent fine-tuning are perfectly possible. While no top-down model that lead to such spectra has as yet emerged, we show that it is nontheless possible to abstract many phenomenological implications of natural supersymmetry.
We discuss prospects for SUSY discovery at the (high-luminosity) LHC, and argue that experiments at the proposed high energy LHC operating at 33 TeV would allow a definitive search for natural SUSY. We will also mention the complementary role of experiments at an electron-positron linear collider with a centre-of-mass energy of 600 GeV for elucidating the nature of a SUSY discovery in this framework.