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In Praise of Unstable Fixed Points: The Way Things Actually Work

Philip W. Anderson
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Abstract

In recent years a fashion has grown up to ascribe great importance to ``quantum critical points'' at T=0, at the boundary between the basins of attraction to the stable fixed points of ordered ground states. I argue that more physical significance in connecting microscopic interactions with observed phenomena lies in the common phenomenon of partially ordered ``liquid'' states at higher temperatures, unstable phases which define the relevant degrees of freedom and may order in many different ways as the temperature is further lowered.

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Philip W. Anderson. 2002-01-23. In Praise of Unstable Fixed Points: The Way Things Actually Work. https://doi.org/10.1016/s0921-4526(02)00770-6

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