Luis Anchordoqui's main area of research involves phenomenology of elementary particles, with applications to high energy astrophysics, cosmology, and collider physics. He has investigated some phenomenological aspects of D-brane string compactifications with low string scale and large extra dimensions, related to experimental searches for physics beyond the Standard Model at the CERN's Large Hadron Collider (LHC). He has also made many influential and creative contributions to our understanding of the earliest moments of the universe based on its baby pictures taken by measuring the cosmic microwave background, the faint glow of radiation generated by the Big Bang.
Anchordoqui has been an active participant in studies aimed at understanding the physics capabilities of the Pierre Auger (cosmic ray) Observatory and NASA's Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) mission. More recently, he contributed to the conceptual design of the Forward Physics Facility (FPF) dedicated to supporting a suite of far-forward experiments at the LHC in the high-luminosity era. The FPF will be located 500 m from the ATLAS detector. It is shielded from the ATLAS interaction point by 100 m of concrete and rock, creating an extremely low-background environment, ideal for many Standard Model studies and new physics searches. For example, the FPF would lead to groundbreaking new capabilities for investigating the nature of dark matter, the origin of neutrino masses, and the imbalance between matter and antimatter in the present-day universe.