Dear all,
We are pleased to announce that on Monday, May 11 at 5.00pm (CET), Lorenzo Lorenzetti (Università della Svizzera italiana) will give the talk A Relational General Relativistic A-theory as part of the Lugano Philosophy Colloquia Spring
2026 organised by the Institute of Philosophy (ISFI) at USI.
This hybrid talk will take place in Room Multiuso FTL Building (USI west campus) and online via Zoom. If you are interested in joining online, please write to events.isfi@usi.ch.
Here is the abstract of the talk: It is often assumed that relativistic physics leaves no room for an A-theory of time. Special relativity seems to rule out a privileged present, while general relativity appears to undermine any physically meaningful notion
of change, given diffeomorphism symmetry. We argue that this conclusion is premature. We develop a general-relativistic A-theory that avoids ad hoc privileged structure, whether local or global, and respects the symmetry structure of general relativity. Drawing
on the framework of relational observables, we defend a gauge-invariant, frame-relative notion of change grounded in physical reference clocks rather than external time. We then argue that, when combined with suitably refined versions of Fine’s external relativism
and fragmentalism, this yields a genuinely A-theoretic account of objective becoming. The result is a non-standard A-theory that preserves irreducible tense while remaining fully compatible with general relativity. (based on joint work with Nicola Bamonti).