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Submission + - Checking the positional invariance of Planck's Consant using GPS (aps.org) 1

gzipped_tar writes: Whether the fundamental constants really stay the same is always a question worth asking. In particular, the constancy of Planck's Constant is something that cannot be simply ignored owing to its universal importance in linking the quantum and classical pictures of our world. Using publicly available GPS data and terrestrial clocks, researchers form the California State University were able to verify that the value of h indeed stays the same across different positions in the vicinity of our Earth. Their result says the local position invariance of h is satisfied within a limit of 0.007. The paper is published in the journal Physical Review Letters (paywalled), and a free-to-read preprint is available on arXiv. tl;dr version for slashdotters: by the well-known formula E = h * f, a hypothetical variation on h induces changes in f, the transition frequency that keeps the time in atomic clocks, both on earth and aboard the satellites. When taking account of other time variations such as general relativistic time dilation, and assuming the invariance of E (atomic transition energy) on physical grounds, we can figure out an upper bound on the variation of h reflected in the measured variation in f.

Submission + - Judea Pearl, a big brain behind artificial intelligence, wins Turing Award (networkworld.com)

alphadogg writes: Judea Pearl, a longtime UCLA professor whose work on artificial intelligence laid the foundation for such inventions as the iPhone’s Siri speech recognition technology and Google’s driverless cars, has been named the 2011 ACM Turing Award winner. The annual Association for Computing Machinery A.M. Turing Award, sometimes called the "Nobel Prize in Computing," recognizes Pearl for his advances in probabilistic and causal reasoning. His work has enabled creation of thinking machines that can cope with uncertainty, making decisions even when answers aren’t black or white.

Comment Re:TFA: Nobody fired for buying IBM (Score 1) 119

Oh come on, get an IDE*. Typo in BibTeX key? It will jump to the offending line and highlight the error. Multiple passes? It manages the compilation process for you.

* Perhaps should be called IAE -- intergrated authoring environment. Personally I use vim-latex but please don't burn me for not using Emacs.

Machines certainly can solve problems, store information, correlate, and play games -- but not with pleasure. -- Leo Rosten