Two Pictures of Laws and Initial Conditions

Chris Wüthrich over at Taking Up Spacetime has an interesting post about laws and initial conditions, and an old objection by Sklar (1984). The post started me thinking about an interesting distinction among laws. In short, there seem to be two fundamentally different kinds of them.

Type 1. Laws that determine possible systems. A physical system is specified by a distribution of potential energy in space and time.

Type 2. Laws that determine the behavior of a given system.

Reasons to love the "Dark Energy Task Force"

It’s official: the words ‘dark,’ ‘energy,’ ‘task,’ and ‘force’ have all been used in the title of a single scientific paper. The “Report of the Dark Energy Task Force” is available here on Obviously, it’s hard not to love a paper like this. The reasons appear to break down roughly as follows.

Of course, as I’ve noted before, there remain many alternatives to dark energy cosmology. But without a title like this, I’m afraid the competition is doomed.

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