10. Physics News from the Web
Items selected from the bulletins of the IOP and the American Institute of Physics.
a) A model approach to climate change
b) 100 DVDs on one disc within three years?
c) Seeing the quantum world
a) A model approach to climate change
http://physicsworld.com/cws/article/print/26946
The Earth is warming up, with potentially disastrous consequences. Computer climate models based on physics are our best hope of predicting and managing climate change, as Adam Scaife, Chris Folland and John Mitchell explain. The extensive article explains the physics behind climate models.
b) 100 DVDs on one disc within three years?
Data stored using micro-holograms. http://physicsworld.com/cws/article/news/39565
Researchers at General Electric claim to have made a key breakthrough in optical data storage that could lead to commercial discs holding the equivalent of 100 DVDs within three years. The new technology is based on the physics of holograms, which enable information to be packed far more densely than with established recording formats. A new device will be needed to play these discs but this will be compatible with established formats like CDs, DVDs and Blu-ray discs, say the US-based team.
Invented over 50 years ago, holograms are now widely deployed as authentication tags, and can be found everywhere from credit cards and passports to cosmetics and pharmaceuticals. These futuristic surfaces can be generated in photosensitive materials by applying two coherent light beams: an “object” beam carrying information about a material’s structure; and a reference beam that records the desired pattern on the hologram. The resulting 3D interference pattern is usually stored as changes in refractive index of the recording material, which can be viewed when the material is illuminated by daylight.
The article links to another very comprehensive article on how the process works.
c) Seeing the quantum world
http://physicsworld.com/cws/article/print/36862
Barry Sanders explains how state-of-the-art animations are taking over the role of classic quantum-mechanical ‘Gedanken’ experiments to help visualize the complexities and challenges of the new quantum technologies
“My interest in scientific visualisation began when I was an undergraduate student at the University of Calgary and saw the film “Powers of 10” for the first time. The film begins and ends with the image of a man asleep at a picnic. In between the first and last scene, we zoom out from the picnic to the vast reaches of space, changing the distance scale by leaps of powers of 10. After reaching the size of the observable universe, at 1024m, the view zooms back to the picnicker and into his hand, ultimately focusing down to the level of a single carbon nucleus, at the scale of 10–16m”
This article links to several in-depth article on visualising quantum mechanics, etc.