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 * **[observation of constructive interference at the edge of quantum ergodicity, by google quantum AI](https://www.nature.com/articles/s41586-025-09526-6)**
     - use of second-order out-of-time-order correlators on a superconducting quantum processor to probe the dynamics of quantum many-body systems, revealing sensitive quantum correlations even at long timescales. potential to unlock hidden details about quantum systems. suggestion of a path to practical quantum advantage, like hamiltonian learning tasks.
+    - **[google's explanation video (quantum echoes)](https://www.youtube.com/watch?v=mEBCQidaNTQ)**