National security, unlocked. Each Thursday, host Mary Louise Kelly and a team of NPR correspondents discuss the biggest national security news of the week. With decades of reporting from battlefields ...

Optical techniques are methods that use light to probe or control matter. One prominent example is optical spectroscopy, which includes such methods as pump–probe spectroscopy, Raman spectroscopy and ...

When we trace emotional imprints back to their root, a moment that was never fully processed, they can complete their cycle ...