Researchers have found that under certain conditions, a laser beam can act like an opaque object and cast a shadow, opening new possibilities for technologies that could use a laser beam to control ...

Natural light profoundly affects our biology, from how well we sleep, to our brain function and immune response. The ancient Egyptians used solar radiation to disinfect and heal chronic wounds and ...

For the experiment, a high-power green laser was directed through ruby cube and illuminated with a blue laser from the side. The green laser increases the optical absorption of the blue illuminating ...