Quantum 'birthmarks' hold lasting traces of a system's past

Some classical physical systems can explore many configurations over time until their long-term behavior no longer reveals their starting conditions. This article has been reviewed according to Science X's editorial process and policies.

Editors have highlighted the following attributes while ensuring the content's credibility: Add to Preferred Sources Physical Review X (2026). A quantum birthmark in a stadium-shaped enclosure.

Credit: Physical Review X (2026). In a paper published in Physical Review X, researchers at Harvard University and other institutions introduced the idea of quantum birthmarks, statistical traces of initial states and early development that persist in quantum systems that do not exchange information with their.

Our framework splits the birthmark effect into two parts: a universal memory factor, omnipresent for any nonstationary (evolving) quantum state and governed by the symmetries of the system, and a revival factor, which arises from early-time recurrences that are related to. Discover the latest in science, tech, and space with over 100, 000 subscribers who rely on Phys. org for daily insights.

The resulting long-term probability patterns retained traces of the particle's starting state and early motion, with quantum scars strengthening the birthmark effect. Our notion of the quantum birthmark moves beyond the analysis of individual eigenstates or eigenenergies that are the dominant lens in quantum chaos research," said Keski-Rahkonen.

In particular, our framework generalizes the idea of scarring from special states tied to periodic orbits to any generic nonstationary quantum state, associated with any classical trajectory.

Fonte