44 results found for light

Several laser-based Atomic Clocks now have an accuracy potential of ~2 x10-18, a hundred-fold better than the best achieved after more than 60 years' experience with rf resonances in Cs atoms. Still, this long attention span documents that the Cs Fou....

The year 2015 has been named the International Year of Light, to mark milestones in the science of light which occurred 1000, 200, 150, 100 and 50 years go. I was a young student in physics in 1965, when the cosmic radiation background was discovered....

Maxwell's electromagnetic theory (now 150 years old) seemed in its comprehensive way to be capable of answering all of the questions one might ever pose about the theory of light. But that spell was broken in 1900 by Planck's discovery that light bea....

The spectrum of a frequency comb, commonly generated by a mode-locked femtosecond laser, consists of several hundred thousand precisely evenly spaced spectral lines. Such laser frequency combs have revolutionized the art of measuring the frequency of....

Joining Philip Schlenoff is Dr. Jeff Owens, from the Physics department at Florida State University, to answer some physics and astrophysics-related questions!

Throughout the 20th century it was widely accepted that a light microscope relying on conventional optical lenses cannot discern details that are much finer than about half the wavelength of light (200-400 nm), due to diffraction. However, in the 199....

Sophie and Stephanie take a light-hearted look at solar energy.

Most of the data we generate and receive (whether emails, tweets, videos or mobile calls) are now carried by optical fibres, which use light to transmit vast quantities of information over trans-oceanic distances. The use of hundreds of wavelengths ....

Light quanta are the fundamental units of radiant energy. When propagating freely they travel at the fastest attainable speed and live forever. These properties recommend them as the ideal messengers for communication of all sorts. Ordinary light ....

During the past decade laser cooling and evaporative cooling of atoms have produced quantum degenerate gases both of bosons (Bose-Einstein condensates) and of fermions (gases with temperatures below the Fermi temperature). Such gases can provide ana....

The image of light waves as oscillating electromagnetic fields explains virtually all the phenomena of traditional optics.  An awareness that these waves are somehow subdivided into quanta has however been with us since the early 20th century.  The....

Using our most advanced techniques and instruments we sift through study the cosmic microwave background as a relic of the early universe to understand the events surrounding the birth and subsequent development of the Universe.  A precision inspect....