Curvature-driven acceleration and a notion of vacuum in Nash theory Soumya Chakrabarti, Soumya Bhattacharya, Rabin Banerjee and Amitabha Lahiri Eur. Phys. J. Plus, 140 4 (2025) 337 Published online: 24 April 2025 DOI: 10.1140/epjp/s13360-025-06258-4