Flutterby™! : Propagation delay inside an atom

Zeptoseconds: New world record in short time measurement

In the global race to measure ever shorter time spans, physicists from Goethe University Frankfurt have now taken the lead: together with colleagues at the accelerator facility DESY in Hamburg and the Fritz-Haber-Institute in Berlin, they have measured a process that lies within the realm of zeptoseconds for the first time: the propagation of light within a molecule. A zeptosecond is a trillionth of a billionth of a second (10-21 seconds).

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Professor Reinhard Dörner adds: “We observed for the first time that the electron shell in a molecule does not react to light everywhere at the same time. The time delay occurs because information within the molecule only spreads at the speed of light. With this finding we have extended our COLTRIMS technology to another application."