Their demon is another atomic nucleus, which interacts with the first as the demon would.

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Radioactivity is measured in Becquerels, which convey the disintegration of an atomic nucleus per second.

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Other ideas include building a detector to see if the spin of an atomic nucleus can be measured, or using the technique as an ultrasensitive antenna.

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This theory holds that in its early history, the observable Universe underwent a period of exponential expansion, doubling in size many dozens of times, growing our observiball a tiny fraction of the size of an atomic nucleus to that of, say, a beach ball.

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This is the point when neutrons released during the break-up of an atomic nucleus are more likely to hit and shatter other nuclei (thus releasing further neutrons), than to escape to the outside world where they merely generate Cherenkov radiation and tear up any living tissue that they pass through.

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