Scientists just proved a fundamental quantum rule for the first time

Scientists have, for the first time, experimentally proven that angular momentum is conserved even when a single photon splits into two, pushing quantum physics to its most fundamental limits. Using ultra-precise equipment, the team captured this elusive process—comparable to finding a needle in a haystack—confirming a cornerstone law of nature at the photon level.

source https://www.sciencedaily.com/releases/2025/08/250816113515.htm