Can the ANITA anomalous events be due to new physics?

Understand

The ANITA collaboration has observed two ultra-high-energy upgoing air shower events that cannot originate from Standard Model neutrinos that have traversed the Earth.

• Several beyond-the-standard-model physics scenarios have been proposed as explanations for these events.
• In this paper we present some general arguments making it challenging for new physics to explain the events.
• One exceptional class of models that could work is pointed out, in which metastable dark matter decays to a highly boosted lighter dark matter particle, that can interact in the Earth to produce the observed events.