54:, "The top-down approach we have described leads to a profoundly different view of cosmology, and the relation between cause and effect. Top down cosmology is a framework in which one essentially traces the histories backwards, from a spacelike surface at the present time. The noboundary histories of the universe thus depend on what is being observed, contrary to the usual idea that the universe has a unique, observer independent history."
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has argued that the principles of quantum mechanics forbid a single cosmic history, and has proposed cosmological theories in which the lack of a past
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is a proposal to regard the many possible histories of a given event as having real existence. This idea of multiple histories has been applied to
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from the current state of the universe to a quantum superposition of possible cosmic histories makes sense.
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naturally leads to multiple histories, called the 'no-boundary proposal', the proposed
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Spoon, M. (2021, February 22). How
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Idea of multiple histories into a complete unified theory .
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has multiple possible cosmologies, and in which reasoning
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