Starkman Glenn D, Trotta Roberto
Astrophysics Department, Oxford University, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK.
Phys Rev Lett. 2006 Nov 17;97(20):201301. doi: 10.1103/PhysRevLett.97.201301. Epub 2006 Nov 16.
We revisit anthropic arguments purporting to explain the measured value of the cosmological constant. We argue that different ways of assigning probabilities to candidate universes lead to totally different anthropic predictions. As an explicit example, we show that weighting different universes by the total number of possible observations leads to an extremely small probability for observing a value of Lambda equal to or greater than what we now measure. We conclude that anthropic reasoning within the framework of probability as frequency is ill-defined and that in the absence of a fundamental motivation for selecting one weighting scheme over another the anthropic principle cannot be used to explain the value of Lambda, nor, likely, any other physical parameters.
我们重新审视那些旨在解释宇宙学常数测量值的人择论证。我们认为，为候选宇宙分配概率的不同方式会导致截然不同的人择预测。作为一个明确的例子，我们表明，根据可能观测的总数对不同宇宙进行加权，会导致观测到一个等于或大于我们目前测量值的Λ值的概率极小。我们得出结论，在将概率视为频率的框架内，人择推理的定义不明确，并且在没有选择一种加权方案而非另一种的基本动机的情况下，人择原理不能用于解释Λ的值，也不太可能用于解释任何其他物理参数。
