# How does electron capture occurs?

Electron capture is a kind of decay by which a nuclear transformation takes place. Below is an example of it.

$$_{29} ^{64} \text{Cu} + e^- \rightarrow _{28}^{64} \text{Ni}$$

Of course, nucleus being positively charged and electron being negatively charged, there is an attraction between them, but electron generally don't fall in the nucleus. I am unable to understand that exactly how does nucleus is able to capture electron, using which interaction or force? Uncertainty principle won't allow electron in nucleus, though it is being captured. Exactly how?

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