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In quantum field theory, a false vacuum is a metastable sector of space that appears to be a perturbative vacuum, but is unstable due to instanton effects that may tunnel to a lower energy state. This tunneling can be caused by quantum fluctuations or the creation of high-energy particles. The false vacuum is a local minimum, but not the lowest energy state, even though it may remain stable for some time. == Stability and instability of the vacuum == For decades, scientific models of our universe have included the possibility that it exists as a long-lived, but not completely stable, sector of space, which could potentially at some time be destroyed upon 'toppling' into a more stable vacuum state.〔 〕〔 〕〔 〕〔 〕〔 〕 If the universe were indeed in such a false vacuum state, a catastrophic bubble of more stable "true vacuum" could theoretically occur at any time or place expanding outward at the speed of light.〔〔 Article cites Fermilab's Joseph Lykken: "The bubble forms through an unlikely quantum fluctuation, at a random time and place," Lykken tells us. "So in principle it could happen tomorrow, but then most likely in a very distant galaxy, so we are still safe for billions of years before it gets to us." 〕 The Standard Model of particle physics opens the possibility of calculating, from the masses of the Higgs boson and the top quark, whether the universe's present electroweak vacuum state is likely to be stable or merely long-lived.〔 〕〔 〕 (This was sometimes misreported as the Higgs boson "ending" the universe). A Higgs mass seems to be extremely close to the boundary for stability (estimated in 2012 as 〔 〕). However, a definitive answer requires much more precise measurements of the top quark's pole mass,〔 and new physics beyond the Standard Model of Particle Physics could drastically change this picture.〔 〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「False vacuum」の詳細全文を読む スポンサード リンク
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