You Can't Travel Back in Time, Scientists Say [yaS stsitneisC ,emiT ni kcaB levarT t'naC uoY]

LiveScience ^ | March 7, 2007 | Sara Goudarzi

[SunkenCiv]

"Wormholes are the future, wormholes are the past," said Michio Kaku, author of "Hyperspace" and "Parallel Worlds" and a physicist at the City University of New York... To punch a hole into the fabric of space-time, Kaku explained, would require the energy of a star or negative energy, an exotic entity with an energy of less than nothing... Another popular theory for potential time travelers involves something called cosmic strings.. Cosmic strings are either infinite or they're in loops, with no ends, said J. Richard Gott, author of "Time Travel in Einstein's Universe" and an astrophysicist at Princeton University. "So they are either like spaghetti or SpaghettiO's."

[SunkenCiv]

:')

[SunkenCiv]

Here's an example of a topic for the String Theory ping list.