to be possible; to be conceivable; to be likely; to be probable
「あり得る」 has another reading with different meanings.
そんなことはあり得ないと思った。
I thought such a thing couldn't be possible.
十分にあり得る話だ。
That's a perfectly plausible story.
専門家でさえ、この結果はあり得たと認めた。
Even experts admitted that this outcome was possible.