Time travel has enchanted and intrigued us since the earliest days of fiction, when authors such as H. G. Wells, Samuel Madden, Charles Dickens and Enrique Gaspar y Rimbau stretched and challenged our imaginations with images and tales of men and women who invented amazing machines and devices that could take them back in time, or forward into the future. But because of the restrictions of light speed, and the paradoxes of going back to the past without damaging the future timeline, and a host of other obstacles and challenges, we, in fact, have remained stuck in the present.
Our scientific knowledge and technological achievement has yet to catch up to the limitless dreams of our imaginations. But perhaps just because we have yet to achieve time travel in our universe, in our particular point along the cosmic arrow of time, doesn't mean it isn't achievable...and maybe the key is the universe itself. Are we limiting ourselves to our understanding only of the laws and possibilities of our universe, and leaving out of the equation other realities, other universes, with other laws and forces, paradoxes and limitation, possibilities and potentialities, far beyond our own?
In 2011, quantum physicists at the University of California at Santa Barbara, led by Andrew Cleland and John Martinis, designed a "quantum machine," as they call it, that might one day lead to proof of time travel and parallel universes. Their machine, a tiny little teleporter barely visible to the naked eye, involves making a tiny metal paddle cool to its ground state, the lowest energy state permissible by the laws of quantum mechanics, and then raising it's energy slowly by a single quantum to produce a purely quantum state of motion. And, they even were able to put the device in both states at once, so it vibrated both slowly and quickly at the same time, in another sort of Schrodinger's Cat state of superposition. They posited that we can only see one of these potential states at once, and upon the act of observation, the state then splits into additional universes. Perhaps, there is a plethora of multiple or parallel universes all around us, but we cannot see them.
