The world’s largest particle accelerator has performed its first collisions, and its first beam acceleration.Progress on the giant experiment has been rapid in the four days since the Large Hadron Collider (LHC) was restarted.According to several sources, these low-energy collisions weren’t expected for another two weeks, but LHC scientists and engineers were obviously very confident that they could put the delay to an end and start smashing protons today.

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