'You Can't Put the Toothpaste Back in the Tube', Can't You, Really?
There are numerous figures of speech illustrating the irreversibility of our actions, ranging from "you can't unring the bell" to "you can't put the toothpaste back in the tube," and they do teach a valuable life lesson. However, while it is true that you cannot unring a bell, the second saying is not as impossible as one would think, as demonstrated by a YouTuber in this case.
In this video by Tyler Bell, you can see how far science can go when you take an idiom on as a challenge. Tyler thought he could place an empty toothpaste tube into a vacuum chamber, remove all of the air, and then let atmospheric pressure do its thing, pushing the toothpaste back into the tube. In order to do that, he started with building a vacuum chamber, and with minimal materials and maximum effort, he was able to accomplish what he wanted to do to some extent. If you're curious to see the project in detail and the results, make sure you watch the video embedded above. Enjoy!