A Faint Glimmer Of Hope For Time Travel

A space-time wormhole lets a particle travel back in time

We may never see practical time travel in our lifetimes, if it’s possible at all. However, a team at the University of Queensland has given the Doc Browns of the world a faint glimmer of hope by simulating time travel on a very, very small scale. Their study used individual photons to replicate a quantum particle traveling through a space-time loop (like the one you see above) to arrive where and when it began. Since these particles are inherently uncertain, there wasn’t room for the paradoxes that normally thwart this sort of research. The particle couldn’t destroy itself before it went on its journey, for example.

As you might have gathered from the “simulation” term, sci-fi isn’t about to become reality just yet. The scientists haven’t actually warped through time — they’ve only shown how it can work. It could take a long time before there’s proof that whole atoms and objects can make the leap, let alone a real-world demonstration. Should you ever step into a time machine, though, you’ll know where it all started… and ended.

Jupiter’s Watery Moon Europa

NASA is plotting a daring robotic mission to Jupiter’s watery moon Europa, a place where astronomers speculate there might be some form of life.FILE - This Feb. 13, 1979 photo released by NASA's …

The space agency set aside $15 million in its 2015 budget proposal to start planning some kind of mission to Europa. No details have been decided yet, but NASA chief financial officer Elizabeth Robinson said Tuesday that it would be launched in the mid-2020s.

Robinson said the high radiation environment around Jupiter and distance from Earth would be a challenge. When NASA sent Galileo to Jupiter in 1989, it took the spacecraft six years to get to the fifth planet from the sun.

Last year, scientists discovered liquid plumes of water shooting up through Europa’s ice. Flying through those watery jets could make Europa cheaper to explore than just circling it or landing on the ice, said NASA Europa scientist Robert Pappalardo .Past NASA probes have flown by Europa, especially Galileo, but none have concentrated on the moon, one of dozens orbiting Jupiter. Astronomers have long lobbied for a mission to Europa, but proposals would have cost billions of dollars.

NASA will look at many competing ideas for a Europa mission, so the agency doesn’t know how big or how much it will cost, Robinson said. She said a major mission goal would be searching for life in the strange liquid water under the ice-covered surface.

Harvard astronomer Avi Loeb said going to Europa would be more exciting than exploring dry Mars: “There might be fish under the ice.”

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