ABSTRACT

We argue that Roberts’s argument for the thesis that absolute velocity is not measurable in a Newtonian world is unsound, because it depends on an analysis of measurement that is not extensionally adequate. We propose an alternative analysis of measurement, one that is extensionally adequate and entails that absolute velocity is measured in at least one Newtonian world. If our analysis is correct, then this Newtonian world is a counterexample to the widely endorsed thesis that if a property varies under the symmetries of a theory then, according to that theory, the property could not be measured. Thus, our paper shows that the debate over the measurability of symmetry-variant properties is more unsettled than previously supposed.

摘要

我们认为，罗伯茨关于绝对速度在牛顿世界中不可测量的论点的论点是不可靠的，因为它依赖于在外延上不够充分的测量分析。我们提出了另一种测量分析，一种在外延上是充分的，并且要求绝对速度至少在一个牛顿世界中被测量。如果我们的分析是正确的，那么这个牛顿世界就是一个被广泛认可的论点的反例，即如果一个属性在一个理论的对称性下发生变化，那么根据该理论，该属性无法被测量。因此，我们的论文表明，关于对称性变体属性的可测量性的争论比以前假设的更加不稳定。