73 years ago today: CP-1, the world's first nuclear reactor, goes critical at the University of Chicago.pic.twitter.com/Y3Z27Rhkig
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
@wellerstein Aha, a critique of critical! #GoogleNgram shows "critical mass" has astrophysical origins in 1880s http://bit.ly/1LPJHd8
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.