The distinction between empirical and virtual data makes an epistemic difference for empiricists. To learn about the natural world, we must put ourselves in the right sort of contact with it. Speculating or simulating alone will not do—empirical constraints on our theorizing are necessary. But what is the ‘right sort’ of contact? Philosophers of science who engage with astrophysics often portray it as a distinctively observational science, since its targets are too distant to experiment upon. While physical manipulation of a target system is neither a necessary nor sufficient condition for good scientific investigation of that target, I have argued that to count as properly empirical, evidence needs to have been derived from a causal chain with one end anchored in the worldly target of interest. On this view, the fact that astrophysical targets cannot be poked and prodded does not in itself undermine our capacity to learn about them through empirical research. However, this view does raise interesting questions in the context of terrestrial laboratory astrophysics experiments. Is the evidence produced in such experiments properly astrophysical evidence? In this talk, I apply my view in a case study of National Ignition Facility research on the effect of high energy flux conditions on the structure of the Rayleigh-Taylor hydrodynamical instability in young supernova remnants. This case illuminates both the arguments needed to justify the epistemic leap from the laboratory to the stars, and also conditions under which those arguments break down.
All of those wishing to attend should email Adam Caulton in order to register attendance.
Philosophy of Physics Seminar Convenor for TT21: Adam Caulton | Philosophy of Physics Group Website