Warping Spacetime: When Theoretical Physics Meets Science Fiction

Abstract

Warp drives, though first envisioned in science fiction, have become a topic of scientific interest within theoretical physics. Miguel Alcubierre was the first one to propose a warp drive spacetime in 1994. His geometry is, however, considered unphysical: it violates all energy conditions and requires large amounts of exotic matter. Several modifications to his metric have been proposed which reduce these energy requirements, but it is still unlikely that warp drives will ever be technologically useful. Even so, they make for very interesting thought experiments, forcing physicists to face the limits of their current theories. Here we will discuss the Alcubierre drive, its energy condition violations, and its energy requirements as obtained from the quantum inequalities. The general definition of superluminal travel is briefly discussed. We also study the horizon problem and the possibility of closed timelike curves within this spacetime. Some recent progress in warp drive research is presented, followed by a conclusion which expands on the physical plausibility and research interest in warp drives.