'There is no conflict between quantum physics and gravity': Physicists sent 20,000 atoms into free fall to prove Einstein's 'happiest thought' - Live Science
Physicists have experimentally confirmed Einstein's equivalence principle at the quantum level by observing 20,000 rubidium atoms in free fall. The study demonstrates that gravity and acceleration remain indistinguishable even for particles in a quantum superposition.
Why it matters
This finding provides a critical bridge between general relativity and quantum mechanics, two pillars of physics that have historically been difficult to reconcile.
Physicists have proven a 100-year-old prediction of relativity by showing that Einstein's equivalence principle holds at quantum scales.
By Andrey Feldman Edited by Brandon Specktor , Laura Mondrag n Published 3 September 2026 In News When you purchase through links on our site, we may earn an affiliate commission. Here's how it works .
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