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SLAC Researchers Discuss Physical Sciences in Popular Blog

Since the inception of blogs in the mid-1990s, the medium has exploded into mainstream arena. The web's most popular blog,, receives 360,000 visits every day. Blogs come in all shapes and sizes—big, small, serious and silly—but all have the same goal; to be read. One blog about the physical sciences,, has succeeded. And two SLAC physicists, JoAnne Hewett and Risa Wechsler, regularly contribute to its pages.

Cosmic Variance began two years ago when experienced physics bloggers Sean Carroll and Mark Trodden approached Hewett and Wechsler with a proposition; join forces in one group blog by a bunch of physicists. Both agreed, and Wechsler helped Carroll design and set-up today's most popular physical science blog. Averaging 4,000 readers per day, Cosmic Variance was the fourth most popular blog in any science field last year, according to Science magazine.

"We attract a large following both inside and outside the physics community," said Wechsler, a theoretical cosmologist at SLAC. "But we write with the general public in mind."

Seven particle physicists and astrophysicists contribute to the website, which ensures new posts appear almost daily and that no one writer ever feels obligated to post when his or her life becomes hectic.

"Blogging is fun but it isn't a first priority," said Hewett, a particle theorist at SLAC. "Doing science comes first."

Wechsler agreed, saying she hasn't had time to blog as much as she would like since she began teaching classes at Stanford last spring. But both see blogging as a wonderful new medium that allows scientists to have a big impact with a low cost in time and effort.

Cosmic Variance has had a big impact already, grabbing readers from all over the world. In fact, when posts have been picked up by larger publications, spikes of 50,000 visits or more have crashed the server. The bloggers constantly receive e-mails requesting certain physical phenomena be covered by their website. In short, Hewett and Wecshler are bringing physics to the masses in a new and expanding way.

"It will be interesting to see how blogging will relate to the Large Hadron Collider when it comes online," said Hewett. "Communicators may start blogs on the daily progress on the machine, and researchers may use private blogs to communicate analyses and results with collaborators."

But don't expect Cosmic Variance to make other media outlets obsolete. Hewett and Wechsler aren't trying to replace anything; they are simply adding a new medium that many people use.

"The posts are about whatever strikes our fancy and are in no way comprehensive or structured," said Hewett. "Otherwise it would be work instead of fun."

Ken Kingery, SLAC Today, August 24, 2007

Above image: Cosmic Variance bloggers Risa Wechsler (left) and JoAnne Hewett.