In the beam of light emitted by a laser pointer, photons travel predominantly along one direction and the beam is therefore said to be collimated. The electric field carried by these photons is ...

Light beams with a helical phase-front possess orbital angular momentum along their direction of propagation in addition to the spin angular momentum that describes their polarisation. Until recently, ...

A new study has challenged a popular explanation for the unexpected 30-second shortening of Dimorphos's orbital period. The researchers found that the proposed mechanism would actually produce the ...