Mourou and Strickland found that stretching a laser out reduced its peak power, which could then be greatly amplified using normal instruments. It could then be compressed to create the short-lived, highly powerful lasers they were after.The technique, which was described in Strickland's first scientific publication, came to be known as chirped pulse amplification (CPA). They were probably unaware at the time that their tools would make it possible to study natural phenomena in unprecedented ways. CPA could also per definition be used to create a laser pulse that only lasts one attosecond, one-billionth of a billionth of a second. At those timescales, it became possible not only to study chemical reactions, but what happens inside individual atoms.
