LTT: Marta Bielinska - Spacetime epistemology in relativistic theories

Marta Bielinska

The Center for Philosophy of Science at the University of Pittsburgh invites you to join us for our Lunch Time Talk. Attend in person at 1117 Cathedral of Learning or visit our live stream on YouTube at https://www.youtube.com/channel/UCrRp47ZMXD7NXO3a9Gyh2sg.

LTT:  Marta Bielinska

Tuesday, November 4th  @ 12:00 pm - 1:30 pm EST

Title: Spacetime epistemology in relativistic theories

Abstract: 

In physics, each spacetime theory presupposes a specific mathematical space used as a spacetime model. For example, spacetime in general relativity is typically considered a (3+1)-Lorentzian manifold that is Hausdorff, time-orientable, and so on. The choice of one such structure over another is usually guided by the dynamics, that is, by answering the question: Is the proposed structure sufficiently rich to account for the physical entities and dynamical equations of our theories? But how do we ensure, for example, that no surplus structure is postulated? A straightforward answer is: through experiment. However, how can we test such spacetime structures or properties? What are the limitations of such experiments?

This puzzle is not new to philosophy. Historically, the question about the epistemic access to the spacetime structure has been famously raised, for example, by Helmholtz (1868, 1896), Reichenbach (1924, 1928), and Poincare? (1902). More recent contributions include those by Gru?nbaum (1973), Sklar (1974), van Fraassen (1970), and Dewar et al. (2022). As the authors of the last article point out, however, this debate has been largely neglected in recent decades in favor of metaphysical controversies, such as the relationism-substantivalism debate.

In this talk, I revise spacetime epistemology from an angle of contemporary physics. Crucially, unlike in the aforementioned discussions on spacetime epistemology which focus either on metrical structure or on dynamical equations, I extend the question of testing spacetime properties to non-metrical spacetime structures, such as topology or differentiable structure.

Therefore, the aim of this presentation is to examine how to test various properties of spacetime  at different levels of its structure – such as orientability at the topological and metric levels – by outlining a systematic overview of such experiments, focusing on their limitations, and indicating possible directions for the further development of the epistemology of spacetime.

This talk will be available online:

Zoom: https://pitt.zoom.us/j/92973594019

YouTube:https://www.youtube.com/channel/UCrRp47ZMXD7NXO3a9Gyh2sg