An empty dance floor where people occasionally appear. Each moves on their own, chaotically, with no connection to the others. But when the right music starts and the hall cools down a bit, the dancers suddenly begin to form long chains and move in unison. That's roughly how electrons behave in a dilute three-dimensional gas.
The authors calculated how the energy of electrons changes under such conditions and found a sharp divergence — a sign of a phase transition. The cause lies in special one-dimensional fluctuations that resemble tiny superconducting 'threads.' These threads are not the electrons themselves, but composite particles called exitrons: an electron surrounded by a cloud of holes. It is through them that superconducting order seeps into the system, although the main mechanism of electron pairing remains plasmonic.
Thus, in an almost empty electron gas, where seemingly nothing should conduct electricity without resistance, a hidden propensity for order is revealed. And this order does not come uniformly throughout the volume, but through one-dimensional channels, like dancers on an empty floor finding the only path to synchronization.
An exitron is not a permanent particle but a virtual entity: it exists only for an instant, yet it manages to influence the behavior of neighboring electrons, like ripples on water from a thrown stone.
In Peter Watts's novel 'Blindsight,' alien beings use quantum effects for instantaneous communication — much like exitrons instantly transmit superconducting fluctuations in a dilute gas.