Asked by: Campbell Leckie, By Email
There are very few hydrogen atoms being created afresh in the Universe. But there are some. Occasionally, a type of radioactivity called ‘proton emission’ can produce a ‘new’ proton and this can form ‘new’ hydrogen by capturing an electron. Hawking radiation can also produce ‘new’ protons and hence ‘new’ hydrogen. Yet both of these processes are extremely rare and inefficient, so the amount of new hydrogen being created is insignificant compared to the amount created in the Big Bang. Since stars are destroying hydrogen in their interiors, the overall amount of hydrogen in the Universe is decreasing over time.
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