Space and Time After Quantum Gravity

As a Visiting Researcher in the Space and Time After Quantum Gravity Project in Late Spring 2018, I will be working on the following project:

Towards the Consistency of Coordination Rules: A Lesson from Reichenbach and Cassirer:

There are few times in the history of science where a space of less than half a century exists in which nearly all of the guiding principles of a science were overturned. In the early twentieth century; however, we find “men of science more or less agog” as a New York Times headline describes it, in 1919 when Einstein’s theory of relativity was empirically confirmed. Philosophers in particular are not accustomed to revising the guiding principles of their science so easily. Hans Reichenbach, in his first book, published just a year after this confirmation, explains that the philosopher, “demands justification for the abandonment of principles.” However, nearly all guiding principles in science exclude some certain kinds of physical statements, and it is just these statements that relativity theory “took as inadmissible.”

As is well known, there is always a sense in which theory is underdetermined by physical evidence, and it is philosophical principles that can narrow down this space of physical possibility. In this paper I will analyze the methods which Reichenbach and later Cassirer outlined for the acceptance, revision, and abandonment of guiding principles in physics in the wake of the revolution of relativity. I will tease our the normative aspects of their work, in which they attempted to not only explain how philosophical principles have shaped physics, but also used this information to determine which interpretive road to take in the future of physics.

Philosophical interpretations of the “admissible” aspects of a theory, after all, are the ladder we use to arrive at further theories, but when kicked too far away in the past, sometimes that ladder is too remote to adjust. Reichenbach and Cassirer, in this way, show how the attention to the evolution of philosophical principles can help us avoid unknowingly restricting or widening the scope of physical possibility. After analyzing their solutions, I will consider in what way the conclusions of these philosophers in the wake of relativity can guide philosophers and physicists in analyzing and establishing guiding principles in contemporary work, such as the search for a theory of quantum gravity.