Speed of light drops to zero at ‘exceptional points’0

• From Around the Web, Science & Technology
• February 1, 2018

Light, which travels at a speed of 300,000 km/sec in a vacuum, can be slowed down and even stopped completely by methods that involve trapping the light inside crystals or ultracold clouds of atoms. Now in a new study, researchers have theoretically demonstrated a new way to bring light to a standstill: they show that light stops at “exceptional points,” which are points at which two light modes come together and coalesce, in waveguides that have a certain kind of symmetry.