Tracking Time with Optical Lattice Clocks

A team of researchers at the University of Tokyo has developed a new type of optical atomic clock that boasts a 100 quadrillionth of a second accuracy. The optical lattice clock is the brain child of Professor Katori who shines his light on possible applications in the video below.

The many hands that make light work want you to see it anew

Physicists around the world are gearing up for the International Year of Light and Light-based Technologies (IYL), which kicks off later this month at an official opening ceremony at the headquarters of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in Paris. Some 1500 delegates are set to converge on the French capital for the event, which runs from 19 to 20 January, and will include representatives from the UN and UNESCO as well as the Nobel laureates Zhores Alferov, Steven Chu, Serge Haroche and William Phillips.

Honestly, they couldn't have picked a better year. 2015 marks the anniversary of several important milestones in the study of light, including the 1000th anniversary of the publication of Ibn al-Haytham's seven-volume treatise on optics. Alhazen's work transformed the way in which light and vision was understood, earning him the title the "father of modern optics". 200 years ago Fresnel proposed that light behaved like a wave, 150 years ago James Clerk Maxwell published his Dynamical Theory of the Electromagnetic Field, a 100 years ago Einstein embedded light in cosmology through general relativity and it's been 50 years since Wilson and Penzias discovered the cosmic microwave background.

"One of the most exciting aspects of this International Year is the way in which it brings together such a wide range of different communities, from astronomy to medicine and photonics to arts and culture," says Beth Taylor, chair of the UK National Committee for the IYL. "It creates a unique opportunity to cross traditional cultural divides and engage new and different audiences with the excitement of light and its applications."

The IYL will consist of a series of co-ordinated events around the world to communicate the importance of light and optical technologies in society – ranging from the Story of Light Festival in Goa, India, to Worldwide Pinhole Photography Day. Hundreds of events are planned in countries all around the world.

You can find out about events near you using light2015's event programme; http://www.light2015.org/Home.html

If you haven not yet seen the amazing BBC4 series Light Fantastic, make this the year you do.

“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.” -Plato

Some other interesting links;
• White light through prism
• A History of Light
• The electromagnetic radiation spectrum

There is more to the universe than what meets the eye

"Realize that there is an underpinning reality, a reality that exists below the reality that we feel with our fingers and see with our eyes"

 What color is the night sky? Black, speckled with stars? Sure, but only to the underdeveloped human eye. Some animals see a completely different sky altogether. With Xperia arc and Dr. Joshua Peek's latest app, you can view the heavens in all their normally unseen glory: X-rays, gamma rays, far infrared, and more.

Slowing down light

By use of a Bose--Einstein condensate, Danish physicist Lene Vestergaard Hau (Harvard University) succeeded in slowing a beam of light to about 17 metres per second, and, in 2001, was able to momentarily stop a beam completely.

About a decade ago, Hau started playing with BECs — for a physicist, that means shooting lasers at them. She found that lasers of the right wavelengths could tune the optical properties of a BEC, giving Hau an almost supernatural command over any other light shined into it.

Her first trick was slowing a pulse of light to a crawl — 25 kmph as it traveled through the BEC. Since then, Hau has completely frozen a pulse and then released it. And recently she shot a pulse into one BEC and stopped it — turning the BEC into a hologram, a sort of matter version of the pulse. Then she transferred that matter waveform into an entirely different BEC nearby — which emitted the original light pulse. That's just freaky. Hey, Einstein may have set that initial speed limit of light, but he only theorized about BECs. "It's not breaking relativity," Hau says. "But I'm sure he would have been rather surprised."

This clip was taken from BBC documentary Absolute Zero.

The unseen eye

"When you gaze long into an abyss the abyss also gazes into you." - Friedrich Nietzsche

Here we see the iris contracting and expanding, regulating the diameter of a gaping black hole, the pupil, and thus controlling the amount of light that enters the eye.

Bonus Pictures: An Extreme close up of the human eye.

GFP

The GFP (Green Fluorescent Protein) exhibits bright green fluorescence when exposed to blue light. Although many other marine organisms have similar green fluorescent proteins, GFP traditionally refers to the protein first isolated from the jellyfish Aequorea victoria. Although it has been used by artists around the world, this GFP is especially useful for the biological sciences. In biology, GFP is used for highlighting specific structures. Compared to other fluorescent proteins, it is much less harmful when illuminated in living cells. The discovery and use of GFP has triggered the development of highly automated live-cell fluorescence microscopy systems, which can be used to observe cells over time expressing one or more proteins tagged with fluorescent proteins. In 2008 Martin Chalfie, Osamu Shimomura, and Roger Y. Tsien were awarded the Nobel Prize in Chemistry for their discovery and development of the green fluorescent protein.

 Wiki - Green Fluorescent Protein

Laser microscopy

Feel like exploring a new world from the comfort of your home? If you shine a laser through a water droplet, the droplet will act as a lens and magnify the image. You just built a laser microscope.

http://www.teravolt.org/microlaser.php
http://makeprojects.com/Project/Laser-Projection-Microscope/413/1

Breaking up light into its spectral colors

I am afraid that by now there are more people who recognize this as the cover of a pink floyd album then there are those who know of this as a very real and iconic scientific experiment. Many people will have seen this image in some form, but if you glaze over it like any other picture, you are missing out. Give yourself a few minutes to really think about it.

"Dispersive prisms are used to break up light into its constituent spectral colors because the refractive index depends on frequency; the white light entering the prism is a mixture of different frequencies, each of which gets bent slightly differently. Blue light is slowed down more than red light and will therefore be bent more than red light." Wiki - Prism Optics

Total Internal Reflection

I recently posted a video showing off the peculiar effect of light being transmitted through 2 mediums without refraction which makes it impossible to distinguish between the mediums resulting in an object becoming invisible. http://wondreal.blogspot.be/2011/09/magic-of-reality.html

Here we see another beautiful effect, total internal reflection, which is used to transmit information in fiber optic cables.

An optical fiber is a flexible, transparent fiber made of very pure glass not much wider than a human hair that acts as a waveguide to transmit light between the two ends of the fiber.

Iridescent Cloud

The multicoloured halo surrounding the peak of this dark cloud looks heavenly, but it's actually an iridescent pileus cloud.

Wiki - Cloud iridescence

The magic of reality

When light moves between two substances with the same index of refraction, the materials cannot be distinguished from one another. The only reason you can see the transparent rod under normal conditions is because light refracts at the edges as it enters another medium (air).