An astrophysicist and his students at Michigan Technological University took to social media in search of the most elusive of research subjects: time travelers!

Robert Nemiroff and his team made an exhaustive search of blogs, Twitter and Facebook to see if anyone had mentioned Pope Francis or Comet ISON before the news items had appeared in the present reality. Since the pope was elected last March and ISON was first detected in September 2012, any mention in 2011 would be proof of time travel, the researchers figured.

But lo and behold, they came up empty-handed. If there are time travelers out there, they buck the general trend of boasting about their travel via social media.

In addition, they asked people in September to tweet "#Icanchangethepast2," but to do it in August. Again, not a peep.

Were they surprised? Not exactly. While Einstein might have spent a lifetime working out the specifics of the space-time continuum, the efforts of Nemiroff and company were more of a lark.

"This wasn't a major research push," Nemiroff said. "This was typing things into search engines. Billions of dollars are spent on time travel movies and books and stuff like that. This probably costs less than a dollar to check on it."

Nemiroff said that time travel isn't his field of expertise and that he didn't believe in it very much before; and believes even less in it now.

"Unless I go back (in time) and publish lots of papers," he quipped.

The results, although rejected by three physics journals, will be presented this week at the American Astronomical Society conference in Washington.

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Astrophysicists hunt for time travelers on Twitter and Facebook
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