Thursday, January 01, 2015

Quick notes: Oil casualty, Drone bombs...


  • Founded by IIT-M alumni: A start-up reimagining e-bikes


  • Bicycling in Bangkok: Two-wheel boom bringing benefits to tourists, locals


  • Why sitting will kill you and what to do about it.


  • Bend it like Albert: For over 2,500 years, scientists had assumed that space was a mere container of the universe, a uniform and amorphous emptiness where objects exist and things happen. Time was viewed as something ever passing, irrespective of what happened.
    “General relativity transformed these ideas completely. It replaced space and time with a jelly-like entity. This jelly can shake, bend, stretch and compress. The equations written by Einstein describe this stretching and bending of space and time itself”.
    Einstein proposed that the presence of mass, through its gravitational tug, can bend space and time and predicted that the Sun’s gravitational field would subtly deflect starlight that passes close to the Sun. Physicists continue to grapple with the challenge of trying to unify two grand theories of physics -- general relativity and quantum mechanics, the laws that govern the sub-microscopic world.
    Two Indian physicists are now among the world's leading authorities in these unification efforts. Abhay Ashtekar at the Pennsylvania State University and Ashoke Sen at the Harish-Chandra Research Institute in Allahabad are independently trying to solve the same problem, but through two competing ideas. Ashtekar is among the pioneers of a unification theory called loop quantum gravity, while Sen has pursued an alternative idea called string theory.

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