Stephen Hawking on Time Travel: The Hidden Science Behind Warping Space-Time

"Why do we think that? Because we have a theory called string theory, it is fantastic it is incredible. It has astounded the world of mathematics, and physics and now you can't move in the physics world without bumping into somebody who wants to talk about the 10th Dimension the 11th Dimension the Multiverse hyperspace time travel. All the things that were once considered science fiction are now centerpiece in our understanding of the nature of everything." Dr. Michio Kaku

"For what I want to say here, knowledge of the book's content is not necessarily required, because it concerns easily understandable facts about the cause and nature of gravitation—the force that presses everything to the ground and is not easily harnessed permanently for propulsion purposes, the force that keeps all celestial bodies in their orbits and holds our entire universe together. How gravitation achieves the feat of creating the conditions for our earthly life remains unexplained by science to this day. Science only offers a series of competing model concepts here. Even the nature of gravitation is largely unknown to it. As Sir Isaac Newton (1643–1727) said at the time: "I have explained the celestial phenomena and the tides based on gravity, but I have not been able to derive the cause of the properties of gravity from the phenomena so far." Nothing has changed since then. One who must know because he struggled daily with the problem of overcoming it, the former deputy chief engineer of the Rolls-Royce aircraft engine works, A. V. Cleaver, summed it up as follows, I quote literally: "Gravity is truly a highly mysterious and elusive phenomenon. It seems questionable whether many people, even technically trained ones, realize how justified this claim is or whether they notice the conspiracy of silence with which gravity is treated in most physics textbooks. It is almost reminiscent of a Polynesian taboo or the Victorian attitude towards certain topics such as sex or particular organs and functions, which were deemed somewhat improper. The student learns that all bodies attract each other, that the stability of the universe is determined thereby, and the equations of Newton's laws describe their effects. Yet—unless he is a specialized graduate student of pure physics—he is still expected to accept the old idea of “action at a distance,” and it is quite unlikely that any of his teachers will draw his attention to our complete ignorance of the physical relationships between gravity and other phenomena, simply because we know nothing about it and because the academic world apparently prefers not to broadcast this fact!"" Otto Jung