Subscribe free to our newsletters via your
. 24/7 Space News .




TIME AND SPACE
A wrinkle in space-time
by Staff Writers
Davis CA (SPX) Jul 24, 2012


Illustration only.

Mathematicians at UC Davis have come up with a new way to crinkle up the fabric of space-time - at least in theory. "We show that space-time cannot be locally flat at a point where two shock waves collide," said Blake Temple, professor of mathematics at UC Davis. "This is a new kind of singularity in general relativity."

The results are reported in two papers by Temple with graduate students Moritz Reintjes and Zeke Vogler, respectively, both published in the journal Proceedings of the Royal Society A.

Einstein's theory of general relativity explains gravity as a curvature in space-time. But the theory starts from the assumption that any local patch of space-time looks flat, Temple said.

A singularity is a patch of space-time that cannot be made to look flat in any coordinate system, Temple said. One example of a singularity is inside a black hole, where the curvature of space becomes extreme.

Temple and his collaborators study the mathematics of how shockwaves in a perfect fluid can affect the curvature of space-time in general relativity.

In earlier work, Temple and collaborator Joel Smoller, the Lamberto Cesari professor of mathematics at the University of Michigan, produced a model for the biggest shockwave of all, created from the Big Bang when the universe burst into existence.

A shockwave creates an abrupt change, or discontinuity, in the pressure and density of a fluid, and this creates a jump in the curvature. But it has been known since the 1960s that the jump in curvature created by a single shock wave is not enough to rule out the locally flat nature of space-time.

Vogler's doctoral work used mathematics to simulate two shockwaves colliding, while Reintjes followed up with an analysis of the equations that describe what happens when shockwaves cross. He found this created a new type of singularity, which he dubbed a "regularity singularity."

What is surprising is that something as mild as interacting waves could create something as extreme as a space-time singularity, Temple said.

Temple and his colleagues are investigating whether the steep gradients in the space-time fabric at a regularity singularity could create any effects that are measurable in the real world. For example, they wonder whether they might produce gravity waves, Temple said.

General relativity predicts that these are produced, for example, by the collision of massive objects like black holes, but they have not yet been observed in nature. Regularity singularities could also be formed within stars as shockwaves pass within them, the researchers theorize.

Reintjes, now a postdoctoral scholar at the University of Regensburg, Germany, presented the work at the International Congress on Hyperbolic Problems in Padua, in June.

.


Related Links
UC Davis
Understanding Time and Space






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








TIME AND SPACE
Time in Space, A Space in Time
Houston TX (SPX) Jul 20, 2012
There are only so many hours in a day, as many people lament while trying to fit in everything they hope to accomplish for work, family and fun. It seems like everyone could use more time. With only 24 hours in a day, people have to divvy up the valuable commodity according to their priorities. This can be a challenging juggling act for anyone, but when you live and work in space, like the crew ... read more


TIME AND SPACE
Another Small Step for Mankind

Russia starts building Moon spaceship, eyes Lunar base

Plans to revisit Moon impeded by financial difficulties

Russia says no manned moon shots till 2018

TIME AND SPACE
Slow-Going at Cape York for Opportunity

ExoMars program gathers strength

Opportunity Runs the First Martian Marathon

NASA Conducts Mission Simulations In Hawaii

TIME AND SPACE
NASA Offers Condolences on the Passing of Pioneering Astronaut Sally Ride

Sally Ride, first US woman in space dead at 61

America Invents Act is a game changer

NASA Completes Another Orion Parachute Test

TIME AND SPACE
Looking Forward to Shenzhou 10

Astronauts in good shape after return

Shenzhou mission sparks 'science fever'

China Beats Russia on Space Launches

TIME AND SPACE
Russian cargo ship fails to dock at ISS: NASA

Russian cargo ship fails to dock at ISS during tests

Japanese Rocket Sends Cargo to ISS

Japan sends cargo to space station

TIME AND SPACE
NASA Partner United Launch Alliance Completes Two Atlas V Reviews

The Spaceport maintains its mission cadence for Ariane 5 flights

S. Korea plans fresh rocket launch in October

NASA Selects Launch Services Contract for Jason-3 Mission

TIME AND SPACE
UCF Discovers Exoplanet Neighbor

Can Astronomers Detect Exoplanet Oceans

The Mysterious Case of the Disappearing Dust

Study in Nature sheds new light on planet formation

TIME AND SPACE
Apple wants billions from Samsung in patent fight

SWF Announces International Dialog on Satellite Servicing and Debris Removal

Tablets to push US electronic sales above $200 bn

Researchers Almost Double Light Efficiency in LC Projectors




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement