Gravity from positivity: Single massive spin-3/2 particle makes gravity logically inevitable, study claims

Researchers at IPhT (CEA, CNRS) and the Universitat Autònoma de Barcelona have shown that gravity—and with it, supersymmetry—emerge as logical necessities whenever a massive spin-3/2 particle exists in nature. Two principles are enough: causality, the fact that no signal can travel faster than light, and unitarity, the requirement that probabilities are conserved in quantum mechanics.

How noise limits today’s quantum circuits

Imagine you’re trying to build a very long, complicated chain of dominoes. The aim is that each domino hits the next one perfectly, all the way down the line, producing an amazing result at the end. A quantum circuit is like a domino chain: a long chain of tiny steps (“operations”) that work together to