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

But as theorists, we could be interested in the theoretical possibility that the right response is to not think about the facts of death at all.

但作为理论家，我们可能对“正确的回应是,根本不考虑所有关于死亡的事实”,在理论上的可能性感兴趣。

耶鲁公开课 - 死亡课程节选

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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What may have seemed like a hyperbolic theoretical possibility at the time has now been embraced, at least by several Federal Appeals court judges.

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