14 DAY TRIAL // Time traveling is being transferred from fiction to reality. A new time machine concept could accomplish an old dream mankind has always had, enabling future generations to travel into the past.
The new approach is not based on exotic, theoretical forms of matter, but still requires technology that we do not have today, and major issues would be the stability of machines traveling back in time. Gravity, bonding matter with spaceand time, is the main focus of this kind of research. Time lines actually return thus creating a loop, or "closed time-like curve."
"We know that bending does happen all the time, but we want the bending to be strong enough and to take a special form where the lines of time make closed loops. We are trying to find out if it is possible to manipulate space-time to develop in such a way.", said theoretical physicist Amos Ori at the Technion-Israel Institute of Technology in Haifa.
Most concepts say time machines require an exotic form of matter named "negative energy density", with peculiar traits like moving in the opposite direction of normal matter when forced. But such matter would be available in amounts too small for the building of a time machine.
Ori's work eliminates this; he started with a donut-shaped hole wrapped within a sphere of normal matter. "We're talking about these closed loops of time, and the simplest kind of closed loops are circles, which is why we have this ring-shaped hole," Ori explained.
Inside the "donut" vacuum, space-time could be bent upon itself employing focused gravitational fields to get to a closed time-like curve. A time traveler would race around inside the donut, being brought back into the past with each lap. "The machine is space-time itself. If we were to create an area with a warp like this in space that would enable time lines to close on themselves, it might enable future generations to return to visit our time.", Ori said.
But the gravitational fields necessary to make such a closed time-like curve could be extremely strong, "on the order of what you might find close to a black hole," Ori told LiveScience. "We don't have any way of creating such strong gravitational fields today, and we certainly have no way of manipulating any such gravitational fields. My calculations suggest any time machine could be very unstable, meaning the tiniest deviations might keep one from working. We need to explore the problem of stability of time machines further.", said Ori.
"It's important if it's right-that there really is some kind of loophole. So this should be scrutinized very closely. The point of such work is to expand the bounds of what's possible, what kind of things we can have and what kinds of things we cannot have.", said theoretical physicist Ken Olum of Tufts University in Medford, Mass., not involved in this research.