Monday, February 18, 2013

Mass of the Higgs Boson Hints at Fate of Universe

In the meantime, physicists have tightened their estimates of the particle's mass: Hill said the current estimate from the Compact Muon Solenoid is 125.8 billion electron volts, or 125.8 GeV, plus or minus 0.6 GeV. The figure from the LHC's other Higgs-boson detector, known as ATLAS, is 125.2 GeV, plus or minus 0.7 GeV.
Those figures can be factored into equations that point to the long-term fate of the universe, said Joseph Lykken, a theoretical physicist at Fermilab.
So what's the outlook?
"If you use all the physics that we know now, and we do what we think is a straightforward calculation, it's bad news," Lykken said. "It may be that the universe we live in is inherently unstable. At some point, billions of years from now, it's all going to be wiped out."
He said the parameters for our universe, including the Higgs mass value as well as the mass of another subatomic particle known as the top quark, suggest that we're just at the edge of stability, in a "metastable" state. Physicists have been contemplating such a possibility for more than 30 years. Back in 1982, physicists Michael Turner and Frank Wilczek wrote in Nature that "without warning, a bubble of true vacuum could nucleate somewhere in the universe and move outwards at the speed of light, and before we realized what swept by us our protons would decay away."

Lykken put it slightly differently: "The universe wants to be in a different state, so eventually to realize that, a little bubble of what you might think of as an alternate universe will appear somewhere, and it will spread out and destroy us."
That alternate universe would be "much more boring," Lykken said. Which led him to ask a philosophical question: "Why do we live in a universe that's just on the edge of stability?" He wondered whether a universe has to be near the danger zone to produce galaxies, stars, planets ... and life.
Even Hill found it interesting that the parameters of particle physics put our universe right along the critical line. "That's something new, which we didn't know before, and which leads some of us to that there's something else coming," Hill said.
When Hill referred to "something else," he was talking about new discoveries in physics — not the end of the world. ...

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