Book Reviewed: The Science of Interstellar, by Kip Thorne and Christopher Nolan

Flying along the perils of a black hole

In a recent 2019 paper published in journal Nature, astronomers glimpsed the blackness of a black hole with an event horizon, the perilous edge against a backdrop of swirling light. This is the gate of hell and the end of spacetime. At a distance from the event horizon, the radio waves emitted by plasma of matter spiraling towards the black hole bends while orbiting the black hole. The resulting light ring is referred to as ‘photon ring’. This is very exciting about a black hole, and you will learn from the best, Caltech Professor Kip Thorne who won the 2018 Nobel prize in physics for his work on gravitational waves.

When the movie Interstellar was released in 2014, this book was also published on the same day. But many physicists rushed to comment on the movie erroneously. Looking back at their comments, I wished they read the book first. Author Kip Thorne discusses the physics behind the path to black hole, Gargantua. Warping of space is the key in the story. The existence of the wormhole connecting the solar system to the far reaches of the universe where Gargantua exist. The distortion of space around the wormhole and Gargantua creates a path for the flight to the distant part of the universe.

Black holes can spin just like earth, and a spinning hole drags space around it into a vortex-type, whirling motion. Like the air in a tornado, space whirls fastest near the hole's center, and the whirl slows as one moves outward, away from the hole. Anything that falls toward the hole's horizon gets dragged, by the whirl of space. But where does space bend to in a black hole? Physicists conjecture that space bends inside a higher-dimensional hyperspace called "the bulk," which is not part of our universe! How do we visualize this? Suppose if we look horizontally along the Sun's equatorial plane, it would appear as a two-dimensional surface, a two-dimensional membrane (brane), and at Sun’s core space bends slightly downward in a higher-dimensional bulk. This is extremely small for a star like Sun but very large for a black hole. When Professor Brand works with equations of relativity, he discovers the possibility of gravitational anomalies triggered by physical fields that reside in the bulk. In fact, the bulk is known to contain much of the gravity that belongs to our universe.

The Tesseract is an enormous, hyper-cubic, grid-like structure and a means of communication for the bulk beings to express action through gravity with Earth. Copper lands in tesseract that is placed by bulk beings near Gargantua, and he is carried into the bulk. The bulk beings can perceive five dimensions including the time dimension; every moment in the past, present, and future. They can influence gravity within any of those time frames.

Director Christopher Nolan wanted the Miller's planet circling Gargantua where one hour is seven years on Earth. Thorne figured out a way out, a black hole can have a maximum spin rate. When a black hole spin is one part in 100trillion smaller than the maximum possible, then that black hole has difficulty capturing objects that orbit in the same direction as the hole rotates. This will get the extreme slowing of time on nearby Miller's planet and such a black hole will not have any harmful jets of radiation streaming through the sky. In addition, the Ranger spacecraft gets a gravitational slingshot maneuver at such an extreme gravity to fly toward Edmund planet.

Life is made of atoms and molecules. Atomic structure evolved in three-spatial dimensions to create specific atomic orbitals in space that leads to the valence structure, like carbon has sp, sp2 and sp3 hybridizations that result in specific spatial orientation leading to various molecular structures. Exposing atoms to four-spatial dimension will destroy the three-dimensional molecular and atomic shapes, and instantly collapses life in the a four-space world. Kip Thorne argues that Cooper is confined to reside in one of the tesseract's three-space-dimensional faces, and he does not experience the tesseract's fourth spatial dimension. This is highly speculative!

Another interesting fact you will learn is that If it is not possible to go backward in time. But you can only do so by traveling outward in space and then returning to spacetime at starting point before you left. You cannot go backward in time at some fixed location, while watching others go forward in time. You can’t engineer your own salvation or exclude your existence by causing the demise of your parents before you were born. That physical reality is strongly favored by the existing laws of physics.

Thorne is a top-notch writer and a narrator of the physics behind the movie “Interstellar.” This book is highly engaging, but some segments may be rough going. That's the nature of real science, it requires thought, but thinking is rewarding, or you may skip rough parts. Thorne explains the fact of this book in three parts, some are science-truths, others are educated guess, and some speculation. The 2019 Nature paper essentially confirms the black hole we saw in the movie Interstellar, and this is described in significant detail in this book.