## Einstein’s self-proclaimed ‘biggest blunder’ might not be a blunder after all

November 28th, 2007 - 12:46 pm ICT by adminWashington, Nov 28 (ANI): A new research by scientists has suggested that Albert Einstein’s theories on the universe might not be a blunder, as he himself believed them to be.

In 1917, Einstein was working on his Theory of General Relativity and was trying to come up with an equation that describes a static universe - one that stands still and does not collapse under the force of gravity in a big crunch. In order to keep the universe static in his theory, Einstein introduced a cosmological constant - a force that opposes the force of gravity.

Then, 12 years later, Edwin Hubble discovered that the universe is not static and is actually expanding. So Einstein scrapped his idea of a cosmological constant and dismissed it as his biggest blunder.

In 1998, however, two teams of scientists, discovered that the universe is not only expanding, but its expansion is actually accelerating - going faster and faster.

“So there had to be some other force that had overcome the force of gravity and is driving the universe into an exponential acceleration,” Nicholas Suntzeff, a Texas A&M researcher said.

This opposing force is what scientists now call dark energy, and it is believed to constitute roughly 74 percent of the universe. The other constituents of the universe are dark matter, which composes about 22 percent of the universe, and ordinary matter, which is about 4 percent.

“Eighty years later, it turns out that Einstein may have been right about a cosmological constant,” said Kevin Krisciunas, a Texas A&M researcher. “So he was smarter than he gave himself credit for,” he added.

To further prove Einstein’s theory, the research team from the Texas A&M University is working on a project called ESSENCE that studies supernovae (exploding stars) to figure out if dark energy - the accelerating force of the universe - is consistent with Einstein’s cosmological constant.

The type of supernovae that the ESSENCE team studies all give off the same amount of energy and have essentially the same peak brightness. Researchers can compare the observed brightness of a supernova that they see in the sky to its known actual brightness to figure out how far away the supernova is.

Researchers also look at what is called the redshift of the supernova, which tells them how fast the universe is expanding. When scientists compare the distance of the supernova to its redshift, they can measure the acceleration of the expansion of the universe. This acceleration is caused by the force scientists call dark energy.

The ESSENCE team can then use the value of the acceleration to figure out the density of dark energy, which they then use to calculate what is called the w-parameter. For Einstein’s cosmological constant to be correct, the w-parameter must equal -1, and so far, the results of the ESSENCE project seem to confirm that it is indeed very close to -1.

“The magic value is -1 exactly,” Krisciunas said. “If the number turns out to be precisely -1, then this dark energy is a relatively simple thing - it is Einstein’s cosmological constant,” he added.

“The team won’t have the final results until later next year, but right now, the measurement is coming in at -1 plus or minus 10 percent error”, said Suntzeff. “So, the initial data seems to point to Einstein being correct,” he added. (ANI)

Tags: 12 years later, accelerating, acceleration, albert einstein, blunder, collapse, cosmological constant, crunch, edwin hubble, faster and faster, force of gravity, scientists, self proclaimed, static universe, theory of general relativity