My students and I are currently working on finding a concrete theory of time travel with multiple histories that is fully compatible with general relativity. The first issue is a practical one: building a time machine seems to require exotic matter , which is matter with negative energy. From quantum mechanics, we know that such matter can theoretically be created, but in too small quantities and for too short times. About Us Our Team. In other words, the time machine is destroyed if and only if it is not destroyed. Anyone seen the keys to my DeLorean? My recent work, together with my students Jacob Hauser and Jared Wogan, shows that there are time travel paradoxes that Novikov's conjecture cannot resolve. Furthermore, the universe would be a much more interesting place if instead of eliminating time travel due to paradoxes, we could just eliminate the paradoxes themselves.