|
''The Theory of Interstellar Trade''〔Krugman, Paul (1978), ("The Theory of Interstellar Trade" ), July 1978〕 is a paper written in 1978 by the economist Paul Krugman. The paper was first published in March 2010 in the journal ''Economic Inquiry''.〔Paul Krugman. ("The Theory of Interstellar Trade" ), ''Economic Inquiry'', March 2010.〕 He described the paper as something he wrote to cheer himself up when he was an "oppressed assistant professor" caught up in the academic rat race. 〔Paul Krugman, ("Economics: the final frontier" ), ''The New York Times'', March 11, 2008〕 Krugman analyzed the question of
Krugman emphasized that in spite of its farcical subject matter, the economic analysis in the paper is correctly done. In his own words,
==Commentary== Responding to the paper, the economist Tyler Cowen speculated on how time travel affects time preference discounting.〔Tyler Cowen, ("The theory of interstellar trade" ), Marginal Revolution, March 11, 2008〕
Assume you have a spaceship that can approach lightspeed and thus you can make, say 1,000 years, seem like 10 years. If you can gain the time value of money 100 times faster, that effectively makes the interest rate 100x higher for you. Thus time preference is meaningless. This is a problem for economic theory. Krugman's solution is to force the interest rate to correspond to the cost of making the trip. Here is the standard compound interest formula: : FV = PV(1+i)n Fuel costs for the above trip are $X. Let us say you have $1,000 to invest and wonder whether it is worth taking a near-lightspeed voyage to increase your return 10 subjective years from now. Stay on earth: : A = $1000(1 + i)10 Take trip: : B = ($1000(1 + i)1000) – $X Krugman says that it is necessarily true that A=B, for time preference theory to stay consistent; thus it will be driven by X. In the future, given a free market, spaceship fuel costs will be the primary determinant of interest rates. The less the fuel cost, the less the interest rate, and vice versa. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「The Theory of Interstellar Trade」の詳細全文を読む スポンサード リンク
|