by Playfuls Staff |
19th April 2006
Thanks to the latest technology available, NASA has managed to achieve a remarkable breakthrough in computer modeling, allowing scientists to basically create
3D simulations and observe how gravitational waves from merging black holes look like, thus providing a whole new perspective in exploring the Universe. [more]
According to Einstein's math, when two massive black holes merge, all of space jiggles like a bowl of Jell-O as gravitational waves race out from the collision at light speed.
Previous simulations had been plagued by computer crashes. The necessary equations, based on Einstein's theory of general relativity, were far too complex. But scientists at NASA's Goddard Space Flight Center in Greenbelt, Md., have found a method to translate Einstein's math in a way that computers can understand.
Similar to ripples on a pond, gravitational waves are ripples in space and time, a four-dimensional concept that Einstein called spacetime. They haven't yet been directly detected.
Massive, colliding objects produce gravitational waves of differing wavelengths and strengths, depending on the masses involved. The Goddard team has perfected the simulation of merging, equal-mass, non-spinning black holes starting at various positions corresponding to the last two to five orbits before their merger.
With each simulation run, regardless of the starting point, the black holes orbited stably and produced identical waveforms during the collision and its aftermath. This unprecedented combination of stability and reproducibility assured the scientists that the simulations were true to Einstein's equations. The team has since moved on to simulating mergers of non-equal-mass black holes.
Einstein's theory of general relativity employs a type of mathematics called tensor calculus, which cannot easily be turned into computer instructions. The equations need to be translated, which greatly expands them. The simplest tensor calculus equations require thousands of lines of computer code. The expansions, called formulations, can be written in many ways.
Through mathematical intuition, the Goddard team found the appropriate formulations that led to suitable simulations.
(Note: image courtesy of nasa.gov)
