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Comment: Remove the ransom note excuse with Deparse (Score 5, Interesting) 536

If you don't like ransom notes (which perl programs may become over time) use this trick: get perl to reformat the code with a this command:

$ perl -MO=Deparse ransom.pl >better.pl

Most of the time that removes the crazy from the script. I just got a large legacy code-base and that little trick made my life much better. If the perl code works, then you are just looking for work to do. Newer is not always better.

+ - Evidence Of A Correction To The Speed of Light

Submitted by KentuckyFC
KentuckyFC (1144503) writes "In the early hours of the morning on 24 February 1987, a neutrino detector deep beneath Mont Blanc in northern Italy picked up a sudden burst of neutrinos. Three hours later, neutrino detectors at two other locations picked up a second burst. These turned out to have been produced by the collapse of the core of a star in the Large Magellanic Cloud that orbits our galaxy. And sure enough, some 4.7 hours after this, astronomers noticed the tell-tale brightening of a blue supergiant in that region, as it became a supernova, now known as SN1987a. But why the delay of 7.7 hours from the first burst of neutrinos to the arrival of the photons? Astrophysicists soon realised that since neutrinos rarely interact with ordinary matter, they can escape from the star's core immediately. By contrast, photons have to diffuse through the star, a process that would have delayed them by about 3 hours. That accounts for some of the delay but what of the rest? Now one physicist has the answer--the speed of light through space requires a correction. As a photon travels through space, there is a finite chance that it will form an electron-positron pair. This pair exists for only a brief period of time and then goes on to recombine creating another photon which continues along the same path. This is a well-known process called vacuum polarisation. The new idea is that the gravitational potential of the Milky Way must influence the electron-positron pair because they have mass. This changes the energy of the virtual electron-positron pair, which in turn produces a small change in the energy and speed of the photon. And since the analogous effect on neutrinos is negligible, light will travel more slowly than them through a gravitational potential. According to the new calculations which combine quantum electrodynamics with general relativity, the change in speed accounts more or less exactly for the mysterious time difference. Voila!"

Comment: Asymmectric networks would be very useful. (Score 1) 79

by ksbraunsdorf (#43393283) Attached to: German Scientists' Visible Light Network Hits 3Gbps
At the library I want to see a list of all the titles in print from my favorite authors, I just use the local WiFi to get the data. For larger downloads I ask on the WiFi, but get the data over the visible light network. So I can see the text of all those books, DRM allowing. Or watch a lecture on the Great Bustard. At airports, my PDA/phone gets all the flight updates on an endless loop, via the visible light network. At Home Depot I'm offered product information and How To videos. I'd love to see the view from the cockpit in real-time while I was flying. If we build really high capacity broadcast networks (like the over-the-air TV used to be), then we'll find uses for them we've never thought about at all. This may even make a computer useful in a class room. I don't believe most of this requires encryption. Mostly an asymmetric network gets us video and large data requests over a cheap, local, and very limited range network. If you want encryption for small slices of data, us the WiFi to do a key exchange.

"Hello again, Peabody here..." -- Mister Peabody

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