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PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE

What if the landscape is for real? Comments on evolving laws and the implications for the issues of time and probability in quantum cosmology
Speaker(s): Lee Smolin
Abstract: The idea that there is not a unique unified theory, but a vast landscape of consistent possible theories, has become popular in the last three years among string theorists and quantum cosmologists. If the idea was rejected too easily when first proposed in the early 90s, it perhaps now has been accepted too uncritically as it has unsettling implications for foundational issues involving time and probability. I will discuss some paradoxes that arise when taking this idea seriously in the context of quantum cosmology, such as "Boltzman's brains" and argue that these come from the unjustified assumption that predictions in quantum cosmology can be made by computing static probability distributions. I then will discuss an alternative point of view, developed in collaboration with Roberto Unger, according to which laws evolve in time, without reaching any static or equilibrium distribution. Implications for the issue of time in classical and cosmological theories will also be discuss.
Date: 08/02/2007 - 4:00 pm
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