[ Saturday, September 20, 2003 (5:31 PM) ] ( link )
Time dilation and SoLs, redux: My previous post on the intersection between time dilation and the running of statutes of limitations has, surprisingly, generated a few responses.
First, James writes in with the following answer: "The court's clock, I would say. If it's anything else, the potential proof problems involved could be intractable."
Next, Kate Nepveu (who, among other things, also used to be a Drew Days small groupie) agrees with James: "Relativity is all about frames of reference. So, the question really is what frame of reference is appropriate, and when you put it that way, the answer is obvious: it's the court's."
Finally, the lawyers get shoved aside as a real physicist gets involved--Chad Orzel posts:
From the standpoint of a physicist, of course, the only appropriate time to use is the time measured by [the space-travelling] Party B's clock. It's the one unique time in the problem, and the shortest time anybody will measure between the two events in question (namely, the wronging of Party A and the filing of charges). The time measured by Party B (in this problem) is even called the "proper time"-- how much clearer an answer could you want?
See also all of the comments on Chad's page. One of the most interesting comments comes from John Novak, who writes, "And here I would have suggested the frame of reference where the damages occurred, which may or may not be the same as the court." Traditional choice-of-law doctrine held that the law to be applied in a torts suit was the law of the place of injury; it therefore does seem to make some sense to impose the same lex loci rule for choice-of-time problems, though there are some rather troubling proof problems with defining the frame of reference in which the injury occurred.
One commenter also says that a short story coming out in Asimov's plays with a similar idea. Well, good luck to the author; the statute of limitations is hardly the most scintillating topic for a science-fiction story, even if you put in big spaceships and near light-speed travel.
[ Wednesday, September 17, 2003 (1:53 PM) ] ( link )
Time dilation and the statute of limitations: As every budding law student and actual lawyer knows, statutes of limitations constrain the amount of time you can wait before bringing a cause of action after it first arises. For instance, if somebody tortiously injures you, you may have anywhere from one to seven years to bring suit; afterward, you'll be barred from suing the tortfeasor, regardless of the merits of your original claim.
As every budding physics student and actual physicist knows, the constant speed of light (as posited in the theory of special relativity) results in the phenomenon of time dilation, whereby (roughly speaking) the faster you go, the slower time seems to pass for you as measured by somebody in another, slower reference frame. Thus, for example, to take the Twin (Non)Paradox, suppose that a pair of twins live together on Earth. They synchronize their watches, then one of them goes on a space ship traveling at .999 the speed of light, out to some distant point and back. When the traveling twin returns, he will only have aged about 5 years (let's say); the Earth-bound twin, however, will be considerably, considerably older.
Ok, now let's suppose that we actually develop near-light-speed space travel, and let's suppose that Party A stays on Earth and Party B goes traveling on a super-fast space ship. Here's my question: given that there is a cause of action between Party A and Party B, should the statute of limitations run according to Party A's clock, or Party B's clock? If it runs according to Party A's Earth-bound clock, then Party B could unfairly run the statute of limitations, and avoid litigation, by traveling for a few months in space--and having several years pass on Earth. If it runs according to Party B's space-ship clock, then several decades could pass before Party B is apprehended, and then all the usual policy reasons in favor of a statute of limitations would come into play (the deterioration of evidence, loss of memory, etc.).
I don't expect this to be an important question any time soon. But hey, it's more fun to think about than the equitable doctrine of laches!