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The passage around this formula

Reading a decoherence time off this table only requires the exponent above: a superposition separated by $\Delta$ x decays with a characteristic time t $\sim$ 1/($\Lambda$\, $\Delta$ $x^2$) . Take the largest grain delocalized over roughly its own diameter, $\Delta$ x $\approx$ 10^{-3} centimetres, and the numbers in the first column turn into times measured in seconds only in the single, almost pathologically clean case of the cosmic background radiation acting alone — about one second. Every other row is not a slower version of the same story; it is a different order of magnitude of story entirely. Ordinary air brings that same superposition down to roughly 10^{-30} seconds, and a superposition…

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