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Washington, Apr 12 (ANI): Physicists, who have been studying the effects caused by the collision of black holes, have discovered a new way to visualize warped space-time.

“We’ve found ways to visualize warped space-time like never before,” Kip Thorne, Feynman Professor of Theoretical Physics, Emeritus, at the California Institute of Technology (Caltech), said.

By combining theory with computer simulations, Thorne and his colleagues at Caltech, Cornell University, and the National Institute for Theoretical Physics in South Africa have developed conceptual tools they’ve dubbed tendex lines and vortex lines.Using these tools, they have discovered that black-hole collisions can produce vortex lines that form a doughnut-shaped pattern, flying away from the merged black hole like smoke rings.

The researchers also found that these bundles of vortex lines-called vortexes-can spiral out of the black hole like water from a rotating sprinkler.

Tendex and vortex lines describe the gravitational forces caused by warped space-time. They are analogous to the electric and magnetic field lines that describe electric and magnetic forces.

Tendex lines describe the stretching force that warped space-time exerts on everything it encounters.

“Tendex lines sticking out of the moon raise the tides on the earth’s oceans,” David Nichols, the Caltech graduate student who coined the term “tendex”, said.

The stretching force of these lines would rip apart an astronaut who falls into a black hole.

Vortex lines, on the other hand, describe the twisting of space. If an astronaut’s body is aligned with a vortex line, she gets wrung like a wet towel.

When many tendex lines are bunched together, they create a region of strong stretching called a tendex. Similarly, a bundle of vortex lines create a whirling region of space called a vortex.

“Anything that falls into a vortex gets spun around and around,” Dr. Robert Owen of Cornell University, the lead author of the paper, said. Tendex and vortex lines provide a powerful new way to understand black holes, gravity, and the nature of the universe.

“Using these tools, we can now make much better sense of the tremendous amount of data that’s produced in our computer simulations,” Dr. Mark Scheel, a senior researcher at Caltech and leader of the team’s simulation work, said.

Using computer simulations, the researchers have discovered that two spinning black holes crashing into each other produce several vortexes and several tendexes.

If the collision is head-on, the merged hole ejects vortexes as doughnut-shaped regions of whirling space, and it ejects tendexes as doughnut-shaped regions of stretching.

But if the black holes spiral in toward each other before merging, their vortexes and tendexes spiral out of the merged hole.

In either case-doughnut or spiral-the outward-moving vortexes and tendexes become gravitational waves-the kinds of waves that the Caltech-led Laser Interferometer Gravitational-Wave Observatory (LIGO) seeks to detect.

“With these tendexes and vortexes, we may be able to much more easily predict the waveforms of the gravitational waves that LIGO is searching for,” Yanbei Chen, associate professor of physics at Caltech and the leader of the team’s theoretical efforts, explained.

Now, equipped with their new tools, Thorne’s team has found the answer. On one side of the black hole, the gravitational waves from the spiralling vortexes add together with the waves from the spiralling tendexes.

On the other side, the vortex and tendex waves cancel each other out. The result is a burst of waves in one direction, causing the merged hole to recoil.

“Though we’ve developed these tools for black-hole collisions, they can be applied wherever space-time is warped,’ Dr. Geoffrey Lovelace, a member of the team from Cornell, said.

“For instance, I expect that people will apply vortex and tendex lines to cosmology, to black holes ripping stars apart, and to the singularities that live inside black holes. They’ll become standard tools throughout general relativity,” he stated.

The team is already preparing multiple follow-up papers with new results.

“I’ve never before co-authored a paper where essentially everything is new. But that’s the case here,” Thorne, who has authored hundreds of articles, said.

The findings were published online on April 11 in the journal Physical Review Letters. (ANI)