The resonance underpinning our existence

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We are carbon-based. That carbon was produced largely in the interiors of stars through a process in which three helium nuclei (alpha particles) fuse together to form a single carbon nucleus. This process is intrinsically unlikely (because it depends on three alpha particles being in the same spot at the same time). But it happens. The reason it does is that the helium atoms bring just the right energy to match one of the energies which a carbon nucleus is allowed to have (according to the rules of quantum physics): the matching of the energies (like the matching of frequencies we have discussed) is a form of resonance.
This resonance (associated with the name of Fred Hoyle, right) is one we should be glad of: we would not be here without it. That it happens seems something of a miracle which features frequently in discussions of the Anthropic Principle.
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