Astronomers study the most elusive force in the Universe

Sep 20, 2011 07:42 GMT  ·  By
Explosion of a Type Ia supernova leading to the formation of a gamma-ray burst
   Explosion of a Type Ia supernova leading to the formation of a gamma-ray burst

A collaboration of researchers from the University of Warsaw (FUW) Faculty of Physics and the University of Naples Federico II announce the development of a new method for measuring cosmic distances. They say their approach uses the properties of gamma-ray bursts for this purpose.

In addition to the obvious use in assessing distances between cosmic objects, the new approach could also be used to obtain new insights into the nature of dark energy, the driving force behind universal expansion. Dark energy is believed to make up 74 percent of the entire cosmic mass.

While dark energy and its companion (dark matter) have been under constant scientific investigation for many years, thus far astrophysicists failed to detect any tangible signs of either of them. Numerous scientific experiments have been set up throughout the world to achieve this objective.

Now, the astronomical collaboration led by FUW expert Dr. Ester Piedipalumbo believes it may use the properties of gamma-rays, the most violent phenomena in the Universe, to obtain a deeper understanding of dark energy, Universe Today reports.

“We are able to determine the distance of an explosion on the basis of the properties of the radiation emitted during gamma-ray bursts,” FUW astronomy professor and science team member Marek Demiański explains.

“Given that some of these explosions are related to the most remote objects in space that we know about, we are able, for the first time, to assess the speed of space-time expansion even in the relatively early periods after the Big Bang,” he adds.

One of the main directions of research in understanding the nature of dark energy is figuring out whether spacetime expands all by itself – directed by Einstein's famous cosmological constant – or if a yet-unknown scalar field inside is driving the ever-accelerating expansion.

In order to establish which of these models is correct, astrophysicists conduct investigations of the Cosmos at various points in its history, trying to determine the nature of dark energy at all times.

This is where gamma-ray bursts (GRB) come in. The team suggests using the violet phenomena to measure distances all the way to the earliest light sources that ever were. This would enable experts to get more insight into the nature of dark energy at the critical times shortly after the Big Bang.

The data the team collected thus far did not reveal anything on the nature of this force. “It is quite a disappointment. But what is important is the fact that we have in our hands a tool for verifying hypotheses about the structure of the Universe. All we need to do now is wait for the next cosmic fireworks,” professor Demiański concludes.