[hep-th/0610267] An Electroweak Oscillon

 Authors: N. Graham Abstract: A recent study demonstrated the existence of oscillons -- extremely long-lived localized configurations that undergo regular oscillations in time -- in spontaneously broken SU(2) gauge theory with a fundamental Higgs particle whose mass is twice the mass of the gauge bosons. This analysis was carried out in a spherically symmetric ansatz assuming invariance under combined spatial and isospin rotations. We extend this result by considering a numerical simulation of the the full bosonic sector of the $SU(2)\times U(1)$ electroweak Standard Model in 3+1 dimensions, with no assumption of rotational symmetry, for a Higgs mass equal to twice the $W^\pm$ boson mass. Within the limits of this numerical simulation, we find that the oscillon solution from the pure SU(2) theory is modified but remains stable in the full electroweak theory. The observed oscillon solution contains total energy approximately 7 TeV localized in a region of radius approximately 0.05~fm. [PDF]  [PS]  [BibTex]  [Bookmark]

Discussion related to specific recent arXiv papers
Tommy Anderberg
Posts: 47
Joined: November 24 2005
Affiliation: independent

[hep-th/0610267] An Electroweak Oscillon

Very interesting paper for several reasons:

- Could provide a minimal (i.e. non-exotic) dark matter candidate reminescent of the "encapsulated atoms" idea of astro-ph/0512454, especially if it turns out to be further stabilized by fermions.

- Unless I've missed something, it's the first dynamically stable, non-trivial electroweak field configuration found since dynamically stable Z-strings were ruled out by rising experimental limits on the Higgs mass, way back in the early 90s. What else is there in "known" territory that hasn't been found yet?

- The computational time required to evolve the electroweak (boson only) equations over 100000 time steps on a modest ~40^3 grid (if I'm reading this correctly) was 72*24 = 1728 hours = 72 days using 2 GHz Opterons. A bit depressing if you happen to be contemplating the possibility of evolving large-scale, random initial configurations numerically (guess why...) and don't own a supercomputer. :(

Maybe I should go BOINC myself.

Addendum: lest I fall in the ubiquitous premature-conclusion trap, I now (November 16, 2006) remind myself that it's really boson-sector-only Z-strings that have been determined to be unstable (for physical values of the weak mixing angle and Higgs mass; see e.g. hep-ph/9402207). In the presence of fermions, things may yet turn out to be different. A (far from exhaustive) search turns up some interesting recent work by Oliver Schröder et.al. on Z-strings stabilizing by binding very large numbers of fermions: hep-th/0601196, hep-th/0607092, QFEXT05 presentation.

Also, Nagasawa and Brandenberger have argued that Z strings are stabilized by plasma effects from the electroweak phase transition all the way down to recombination (!) (hep-ph/0207246).