Rigidity in Relativity 

Given on 14 June 2008 at the Third International Conference on the Nature and Ontology of Spacetime. 


A short summary is available at the website in portable document format. I became interested in the way the notion of rigidity, and in particular, rigid motion of accelerating objects, is extended to the universe of special relativity because I had been trying to do self-force calculations for spatially extended charge distributions.  A detailed account of this theme was published as: ​Rigidity and the ruler hypothesis. In: V. Petkov (ed.), Space, Time, and Spacetime. Physical and Philosophical Implications of Minkowski's Unification of Space and Time, Springer, Berlin, Heidelberg, New York (2010). This was the beginning of a wider interest in the status of acceleration in relativity theories.

Self-Force and Inertia. Old Light on New Ideas

Given as a Philosophy of Physics Research Seminar at the University of Oxford on 26 November 2009.


This was a summary of the second book, which has the same title. It is to their credit that such an active philosophy of physics group should find a space for an outsider. Hopefully, they also benefit from this kind of rough input. As a result of remarks after the talk, I was able to identify a mistake in my second book. The discussion of this mistake is available in portable document format (updated July 2014). This file contains considerable advances on the discussion in my book on the self-force.



Electromagnetic Radiation and the Coming of Age of the Equivalence Principle

Given on 24 March 2011 at Bad Honnef in Germany as the WE Heraeus Seminar 475 entitled Problems and Developments of Classical Electrodynamics.


This talk was an overview of the first book. A summary of the talk is available in portable document format. Since scientists reading this website will be concerned about my credentials, I note that the organisers of this meeting, Volker Perlick and Domenico Giulini, asked me to be one of the main speakers purely on the basis of my first book.


Self-Force and Inertia. Old Light on New Ideas

Given at the University of Munich on 30 June 2011 at a conference in honour of Detlef Dürr on the occasion of his sixtieth birthday. 


This was a much improved synopsis of my second book, with corrections and additions. A summary of the talk is available here in portable document format.

Self-force and inertia
Accelerating frames
Accelerating frames
Self-force and inertia