What is the Nature of Space and Time?
July 28 - August 2, 2008
Department of Philosophy, University of Geneva
Held at:
Hotel du Mont-Collon
Monica and Vincent Anzévui
CH-1986 Arolla VS
My contribution to the program consists of
three lectures.
John D. Norton
Department of History and Philosophy of Science
Center for Philosophy of Science
University of Pittsburgh
homepage
Causal talk and causal notion permeate our discussions both inside and outside science. Most us feel that we have not really understood a phenomenon until we have a grasp of the causal processes that underlie it. Is this pervasive use of causal talk merely a convenient language through which we can readily picture the processes of the natural world? Or does it derive from a deeper fact about nature that is antecedent to all science? That deeper fact I call "causal fundamentalism." It presupposes that the world is governed by a factual principle of cause and effect and that the burden of the individual sciences is to find its expression in their particular domain.
I will describe a form of skepticism about causation that denies this doctrine of causal fundamentalism. It will be defended by general arguments and also through an examination of the causal principles that form part of the foundations of many physical theories.
Readings:
John D. Norton, "Causation as Folk Science," Philosophers' Imprint Vol. 3, No. 4 http://www.philosophersimprint.org/003004/
John D. Norton, "Do the Causal Principles of Modern Physics Contradict Causal Anti-Fundamentalism?" pp. 222-34 in Thinking about Causes: From Greek Philosophy to Modern Physics . eds. P. K. Machamer and G. Wolters, Pittsburgh: University of Pittsburgh Press, 2007. http://www.pitt.edu/~jdnorton/papers/Causation_PKVII_final.pdf
An optional reading for those who are really keen:
John D. Norton, "Is There an
Independent Principle of Causality in Physics?" http://www.pitt.edu/~jdnorton/homepage/cv.html#On_Frisch
(This is my end of a debate with Mathias
Frisch over whether dispersion theory requires an independent principle of
causality.)
No one in science, not even an Einstein, makes worthy discoveries without undertaking a systematic investigation. What sorts of conceptions governed the systematic part of Einstein's investigations? I will outline one notion that played an important role in Einstein's discovery of general relativity. It is Einstein's distinction between thinking physically and thinking formally. I will illustrate how Einstein consciously shifted back and forth between these two modes of thinking in the years leading up to his discovery of general relativity. We will see some pages from Einstein's "Zurich Notebook" which contains Einstein's scratch pad calculations at the decisive period of his discovery of general relativity.
Readings:
John D. Norton, "'Nature in the Realization of the Simplest Conceivable Mathematical Ideas': Einstein and the Canon of Mathematical Simplicity," Studies in the History and Philosophy of Modern Physics, 31 (2000), pp.135-170. http://www.pitt.edu/~jdnorton/papers/Einstein_simplicity.pdf
John D. Norton, "A Peek into Einstein's Zurich Notebook," Goodies Page. http://www.pitt.edu/~jdnorton/Goodies/Zurich_Notebook/index.html
For an easy read on a big topic:
John D. Norton, "How
Did Einstein Think?" Goodies Page http://www.pitt.edu/~jdnorton/Goodies/Einstein_think/index.html
Optional: For a fairly detailed reconstruction of one episode, see:
John D. Norton, "A
Conjecture on Einstein, the Independent Reality of Spacetime Coordinate
Systems and the Disaster of 1913," pp. 67-102 in A. J. Kox and J.
Einsenstaedt, eds., The Universe of General Relativity. Einstein Studies
Volume 11. Boston: Birkhaeuser, 2005. http://www.pitt.edu/~jdnorton/papers/Conjecture_HGR6.pdf
It has been known for a long time that classical Newtonian physics admits indeterministic systems. They are systems whose present state does not fix their future. These long-known failures of indeterminism, however, have involved exotic systems, such as "space invaders" that rush in from spatial infinity at arbitrarily high velocities; or "supertask systems" in which an infinite collection of masses at rest spontaneously sets itself into motion.
One might convince oneself that these systems can be ignored because they are too exotic to take seriously. That attitude is harder to maintain for the case of the dome. In it, a mass sits at the top of a dome with a specified shape, over which it can slide freely. Newton's laws permit the mass to stay there indefinitely; and, as two lines of calculus show, also permit the mass spontaneously to move at any time and in any direction.
The dome is interesting not just since it displays an interesting sense in which Newtonian physics is indeterministic. It also raises a series of broader questions: Just what is Newtonian physics? Just which idealization are permitted? What does it mean to say a system is "physical"? This last notion proves to be a notion of possibility peculiar to physics that has slipped under the modal philosopher's radar.
Readings:
The dome is described briefly with animations in: John D. Norton, "The Dome: A Simple Violation of Determinism in Newtonian Mechanics" Goodies page (Section 3 of "Causation as Folk Science") http://www.pitt.edu/~jdnorton/Goodies/Dome/index.html
John D. Norton, "The Dome: An
Unexpectedly Simple Failure of Determinism" Proceedings of the 2006
Biennial Meeting of the Philosophy of Science Association, Philosophy of
Science, forthcoming.
Short version for publication: http://www.pitt.edu/~jdnorton/papers/DomePSA2006_short.pdf
Original longer version: http://www.pitt.edu/~jdnorton/papers/DomePSA2006.pdf
For an easy introduction into Einstein's physics, see my
web*bookTM, Einstein for Everyone.
July 2, 2008