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What the World Looks Like, If You Move Backward in Time [Video]

The views expressed are those of the author and are not necessarily those of Scientific American.

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Oops, I said my last post on the recent Foundational Questions Institute conference would be my final one, but I can’t resist just one more. At the conference, Gavin Crooks at Lawrence Berkeley Labs, who studies molecular machines and gave a great talk on how life balances time asymmetry with thermodynamic efficiency, showed this brilliant short film by Rocketboom. In it, a woman walks, skips, and jump-ropes through the streets of New York while everyone else moves backwards. Of course, she’s the one moving backwards—a vivid illustration of the time-reversibility of the laws of physics.

As Crooks noted, the most remarkable thing is how the passers-by seem not to notice. A New York minute, it seems, is not just sped up, but time-reversal invariant.

George Musser About the Author: is a contributing editor at Scientific American. He focuses on space science and fundamental physics, ranging from particles to planets to parallel universes. He is the author of The Complete Idiot's Guide to String Theory. Musser has won numerous awards in his career, including the 2011 American Institute of Physics's Science Writing Award. Follow on Twitter @gmusser.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. Ednamae 9:51 am 09/27/2011

    I loved this video and music. I am showing to my grandchildren.

    Does anyone know the title of the music that was playing and how I could purchase it on CD or MP3. I thought the music was beautiful. I hope someone out there or the author, George Musser, can tell me. I am not on twitter or facebook – so email

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  2. 2. dantevialetto 5:00 pm 10/2/2011

    But if one is going backward in time, also the light is going back in time, and instead to be emitted it will be absorbed! So the sun will be black and one can see nothing!

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  3. 3. Joe V. 6:58 pm 10/3/2011

    Nice thought experiment. Going back in time just isn’t possible though. Time is a purely artificial construct of man, to measure guage causality. There is only now and that’s the same everywhere.

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