It's a theoretical possibility.

这是理论上存在的可能性。

《牛津词典》

It's only a theoretical possibility.

这只是一种假设的可能性。

youdao

It's a theoretical possibility, but I don't suppose it will happen.

这是一种理论上的可能性，但我认为这种情况不会发生。

youdao

Programmers knew that it was a theoretical possibility, and that it would have revolutionary implications if it could be made to work.

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Both campaigns have teams of lawyers ready for legal challenges in various states, and lengthy recounts are more than a theoretical possibility.

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There is a theoretical possibility that traces of pesticides used in food production may remain on products such as fruit and vegetables that have been sprayed.

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