Did A 'Sleeper' Field Awake To Expand The Universe?

[boedicca]

This is very coolth: the universe is expanding rapidly.

More final frontier for everyone!

(And note the appearance of USMB's Ringel trying to pass for a Belgian.)

IT'S the ultimate sleeper agent. An energy field lurking inactive since the big bang might now be causing the expansion of the universe to accelerate.

In the late 1990s, observations of supernovae revealed that the universe has started expanding faster and faster over the past few billion years. Einstein's equations of general relativity provide a mechanism for this phenomenon, in the form of the cosmological constant, also known as the inherent "dark energy" of space-time. If this constant has a small positive value, then it causes space-time to expand at an ever-increasing rate. However, theoretical calculations of the constant and the observed value are out of whack by about 120 orders of magnitude.

To overcome this daunting discrepancy, physicists have resorted to other explanations for the recent cosmic acceleration. One explanation is the idea that space-time is suffused with a field called quintessence. This field is scalar, meaning that at any given point in space-time it has a value, but no direction. Einstein's equations show that in the presence of a scalar field that changes very slowly, space-time will expand at an ever-increasing rate.

Now Christophe Ringeval of the Catholic University of Louvain (UCL) in Belgium and his colleagues suggest that a quintessence field could be linked to a phase in the universe's history called inflation. During this phase, fractions of a second after the big bang, space-time expanded exponentially. Inflation is thought to have occurred because of another scalar field that existed at the time. But what if a much weaker quintessence field was also around during inflation?

According to the UCL team's models, inflation would have induced quantum fluctuations in the quintessence field. When the universe began its more sedate expansion after inflation ended, the field and its fluctuations would have been frozen into the fabric of space-time, so that the energy density of the field did not change with time.

This field would have had no impact on the early universe, which would have been dominated by matter and radiation. But eventually, as the universe grew, its expansion rate slowed down and the influence of matter and radiation diminished, the relative strength of the quintessence field increased, causing the expansion of space-time to accelerate, says Ringeval...

Did a 'sleeper' field awake to expand the universe? - space - 11 June 2010 - New Scientist

 

[bruzz]

The question is: what is the universe expanding into? Also will it reach a maximum and then contract as rapidly, like an anti-matter bomb?

 

[waltky]

Granny says, "Dat's right - dat's why dat meteor slammed into Russia...

Cosmos may be 'inherently unstable'
19 February 2013 - Scientists say they may be able to determine the eventual fate of the cosmos as they probe the properties of the Higgs boson.

A concept known as vacuum instability could result, billions of years from now, in a new universe opening up in the present one and replacing it. It all depends on some precise numbers related to the Higgs that researchers are currently trying to pin down. A "Higgs-like" particle was first seen at the Large Hadron Collider last year. Associated with an energy field that pervades all space, the boson helps explain the existence of mass in the cosmos. In other words, it underpins the workings of all the matter we see around us. Since detecting the particle in their accelerator experiments, researchers at the Geneva lab and at related institutions around the world have begun to theorise on the Higgs' implications for physics.

One idea that it throws up is the possibility of a cyclical universe, in which every so often all of space is renewed. "It turns out there's a calculation you can do in our Standard Model of particle physics, once you know the mass of the Higgs boson," explained Dr Joseph Lykken. "If you use all the physics we know now, and you do this straightforward calculation - it's bad news. "What happens is you get just a quantum fluctuation that makes a tiny bubble of the vacuum the Universe really wants to be in. And because it's a lower-energy state, this bubble will then expand, basically at the speed of light, and sweep everything before it," the Fermi National Accelerator Laboratory theoretician told BBC News. It was not something we need worry about, he said. The Sun and the Earth will be long gone by this time. Dr Lykken was speaking here in Boston at the annual meeting of the American Association for the Advancement of Science (AAAS). He was participating in a session that had been organised to provide an update on the Higgs investigation.

Two-year hiatus

The boson was spotted in the wreckage resulting from proton particle collisions in the LHC's giant accelerator ring. Data gathered by two independent detectors observing this subatomic debris determined the mass of the Higgs to be about 126 gigaelectronvolts (GeV). That was fascinating, said Prof Chris Hill of Ohio State University, because the number was right in the region where the instability problem became relevant. "Before we knew, the Higgs could have been any mass over a very wide range. And what's amazing to me is that out of all those possible masses from 114 to several hundred GeV, it's landed at 126-ish where it's right on the critical line, and now we have to measure it more precisely to find the fate of the Universe," he said. Prof Hill himself is part of the CMS (Compact Muon Solenoid) Collaboration at the LHC. This is one of the Higgs-hunting detectors, the other being Atlas. Scientists have still to review about a third of the collision data in their possession. But they will likely need much more information to close the uncertainties that remain in the measurement of the Higgs' mass and its other properties. Indeed, until they do so, they are reluctant to definitively crown the boson, preferring often to say just that they have found a "Higgs-like" particle.

Frustratingly, the LHC has now been shut down to allow for a major programme of repairs and upgrades. "To be absolutely definitive, I think it's going to take a few years after the LHC starts running again, which is in 2015," conceded Dr Howard Gordon, from the Brookhaven National Laboratory and an Atlas Collaboration member. "The LHC will be down for two years to do certain repairs, fix the splices between the magnets, and to do maintenance and stuff. So, when we start running in 2015, we will be at a higher energy, which will mean we'll get more data on the Higgs and other particles to open up a larger window of opportunity for discovery. But to dot all the I's and cross all the T's, it will take a few more years." If the calculation on vacuum instability stands up, it will revive an old idea that the Big Bang Universe we observe today is just the latest version in a permanent cycle of events. "I think that idea is getting more and more traction," said Dr Lykken. "It's much easier to explain a lot of things if what we see is a cycle. If I were to bet my own money on it, I'd bet the cyclic idea is right," he told BBC News.

MORE BBC News - Cosmos may be 'inherently unstable'

See also:

Contact lost with space station
19 February 2013 - Nasa ground controllers have lost contact with the International Space Station because of a computer problem.

Flight controllers in Houston were updating software on board the ISS's flight computers this afternoon (GMT) when one of the station's data relay systems broke down. But the ISS has been able to make contact intermittently via Russian ground stations. Nasa told the crew to connect a backup computer to begin restoring contact.

The ISS currently has a six-person crew

The primary computer that controls critical station functions defaulted to a backup computer, but it was not letting the station communicate with Nasa's Tracking and Data Relay Satellites, the US space agency said. The problem occurred at about 0945 EST (1445 GMT).

The ISS marked its 10th anniversary of continuous human occupation on 2 November 2010. Since Expedition 1 in 2000, the space station has been visited by 204 individuals. The current crew is made up six men: two Americans, three Russians and a Canadian.

http://www.bbc.co.uk/news/science-environment-21512322

 

[Politico]

The question is: what is the universe expanding into? Also will it reach a maximum and then contract as rapidly, like an anti-matter bomb?

Since we'll never get there does it really matter....

 

[Procrustes Stretched]

Belgians make good dark chocolate