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Time seems to have an "arrow," whereas the spatial dimensions are ambidextrous. Given the unity between time and space, it leads to the obvious question: Is time travel, of any sort, possible?

Physicist Michio Kaku says new CERN experiments suggest time travel could be possible. Also, Wisconsin Gov. Scott Walker talks with WSJ editorial board members about how his state is outcompeting ...

Researchers have discovered that it’s possible to speed up, slow down, or reverse the flow of time in a quantum system. This ...

A scientist has mathematically proven the physical feasibility of paradox-free time travel. But once you go back, you might not like what you find.

Ronald Mallett, professor emeritus at the University of Connecticut, is most known for his theory on how time travel is possible.

However, physicist John D. Norton has developed a new model based on Einstein's theory of general relativity that shows time travel is mathematically possible.