The top and Higgs mass determination arose the old discussion about electroweak vacuum metastablity. There is an interesting fact that with available data or universe place in the edge of stable and meta-stable zone tends to be inside the meta-stable region. This conclusion confirms up to 3-loop renormalization group and even shows convergence. I know that changing the electroweak vacuum propertionally changes the top and higgs masses. But what I cant realize is that how the stability and meta-stability boundaries move. So to speak, can the universe become stable by new high energy physics emergence as =246Gev replacement?
By modifying physics at a higher energy scale, I think you can do almost anything.
The question is whether the standard model is stable on its own, or has another negative minimum for very large field values. The answer to the last question is much more subtle than often discussed, since most properties of the effective potential, and the field on which is depends, are gauge dependent and dependent on the renormalization scale. More discussions can be found in the linked papers.
http://arxiv.org/pdf/1408.0292v2.pdf
http://ntnu.diva-portal.org/smash/record.jsf?pid=diva2%3A657416&dswid=2272
http://arxiv.org/pdf/1408.0287.pdf
When we write down the Higgs potential, we exclude gravitational effects. But on plain dimensional grounds one can write down extra (non renormalizable) terms Φ6/MP2 and Φ8/MP4 plus higher terms. Then, the Higgs potential will develop local minima at higher expectation values of the Higgs field. Then if the new vacuum is lower than the electroweak vacuum, a new possibility opens up. The electroweak vacuum becomes metastable, as, the new minimum could be lower than the present one for ranges of parameter space of Higgs potential. Then a curious option comes along which is that of the vacuum decay.
In a recent paper Philipp Burda, Ruth Gregory, Ian G. Moss, (http://arxiv.org/abs/1503.07331) (JHEP 08 114 (2015) ) have explored this scenario. They conclude that "black holes can massively speed up the rate of decay of a metastable Higgs vacuum by acting as nucleation sites" they also conclude that the lifetime of our universe in a metastable Higgs phase depends on the absence of what they call nucleation seeds. Presence of primordial black hole could reduce the time it takes to decay to a lower energy vacuum.
An old reference on this topic is; GRAVITATIONAL EFFECTS ON AND OF VACUUM DECAY, Sidney Coleman and Frank De Luccia
http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-2463.pdf
- Badges
- Science topic
- Similar topics
- Geoscience
- Asia
- India