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Lasers Approach Their Ultimate Intensity Limit 384

Flash Modin writes "Death Star style superlasers? Don't bet on it. High-power lasers currently in development appear to be nearing the theoretical laser intensity limit, according to new research set to be published in the journal Physical Review Letters. Ultra-high-energy laser fields can actually convert their light into matter as shown in the late '90s at the Stanford Linear Accelerator (SLAC). This process creates an 'avalanche-like electromagnetic cascade' (also known as sparking the vacuum) capable of destroying a laser field. Physicists thought it might be a problem for lasers eventually, but this work indicates the technology is much closer to its limit than researchers believed. A preprint is available here."
Social Networks

Sharing the Perseids With #Meteorwatch 55

astroengine writes "The Perseid meteor shower is just beginning as the Earth passes through the dusty trail left behind by comet Swift-Tuttle. The meteor count is set to peak on Aug. 12. In a grand social media experiment, a guy (in a shed) located in the south of the UK is restarting #Meteorwatch, a Twitter-based community of shooting star observers. Last year, during the Geminid meteor shower, thousands of 'virtual observers' participated, making this one of the largest astronomy gatherings of its kind. With some new gadgets and a Hollywood-style #Meteorwatch trailer at his disposal, Adrian West is spending many sleepless nights counting meteors with the rest of the world." It's too bad it doesn't get dark until after my kid's bed time. In another year or two, I really am looking forward to exposing him to the Perseids.

Feed Sea Snails Break The Law (

Lizards gave rise to legless snakes. Cave fishes don't have eyeballs. In evolution, complicated structures often get lost. Dollo's Law states that complicated structures can't be re-evolved because the genes that code for them were lost or have mutated. A group of sea snails breaks Dollo's law, according to scientists.

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