Mattia thought that he and Alice were like that, twin primes, alone and lost, close but not close enough to really touch each other.

She tried to open the bottle, but the top slipped through her fingers without moving. He took the bottle from her hand and opened it with his thumb and index finger. There was nothing special in the gesture and yet she found it strangely fascinating like a small heroic feat performed specially for her.

Twin primes: pairs of prime numbers that are close to each other, almost neighbors, but between them there is always an even number that prevents them from truly touching. If you go on counting, you discover that these pairs gradually become rarer, lost in that silent, measured space made only of ciphers. You develop a distressing presentiment that the pairs encountered up until that point were accidental, that solitude is the true destiny. Then, just when you’re about to surrender, you come across another pair of twins, clutching each other tightly.

The love of those we don't love in return settles on the surface and from there quickly evaporates.

You'll get used to it. In the end you won't even notice it anymore," he said. "How is that possible? It will always be there, right before my eyes." "Exactly," said Mattia. "Which is precisely why you won't see it anymore.

It was strange to find them here, still alive, with their shared bits of past that suddenly counted for nothing.

Why did you choose to stay here?" (...) "I don't know," he said. "It's as if there's more oxygen here.