`Interstellar` film technology decodes spinning black holes

London: The team responsible for the stunning visual effects in filmmaker Christopher Nolan's epic film "Interstellar" has turned science fiction into facts by providing new insights into the powerful effects of black holes.

The team described an innovative computer code that was used to generate the movie's iconic images of the wormhole, black hole and various celestial objects and explain how the code has led them to new science discoveries.

Using their code, the "Interstellar" team found that when a camera is close up to a rapidly spinning black hole, peculiar surfaces in space - known as caustics - create more than a dozen images of individual stars and of the thin, bright plane of the galaxy in which the black hole lives.

London-based visual effects company Double Negative and theoretical physicist Kip Thorne from the California Institute of Technology found that the images were concentrated along one edge of the black hole's shadow.

These multiple images are caused by the black hole dragging space into a whirling motion and stretching the caustics around itself many times.

"It is the first time that the effects of caustics have been computed for a camera near a black hole, and the resulting images give some idea of what a person would see if they were orbiting around a hole," Thorne explained.

The discoveries were made possible by the team's computer code which mapped the paths of millions of lights beams and their evolving cross-sections as they passed through the black hole's warped spacetime.

The computer code was used to create images of the movie's wormhole and the black hole called Gargantua and its glowing accretion disk with unparalleled smoothness and clarity.

It showed portions of the accretion disk swinging up over the top and down under Gargantua's shadow, and also in front of the shadow's equator, producing an image of a split shadow that has become iconic for the movie.

"This new approach to making images will be of great value to astrophysicists like me. We, too, need smooth images," Thorne added.

The paper was published in the journal Classical and Quantum Gravity.