The recent Hollywood movie Interstellar (production cost $ 165 million) turned out to be a blockbuster in the U.S. and Europe, and most likely will be so in Asia. The movie story is great. Without doubt, one of its benefits is the renewed enthusiasm in the science of space flight by the public. But alas, it is only HollywoodÂs science fiction, not science, despite the efforts of the producer. The basic reason is that General Relativity (GR) alone does not provide a sufficient basis for the underlying physics. Additional constraints from quantum theory have to be observed, and, when applied, render the existence of wormholes, though allowed by GR, completely unphysical. However, despite this negative result, an alternative concept for propellantless propulsion might exist in the form of novel gravity like-fields, which is briefly presented.