Image credit: Amin, et al. ©2012 American Physical Society
Bobbing waves may have dominated early universe.
(Phys.org) -- Localized waves that bob up and down without dissipating their energy, called “oscillons,” may have dominated the early universe shortly after inflation. A collaboration of physicists from MIT, Yale University, and Stanford University has discovered that copious amounts of oscillons arise in simulations based on several realistic inflationary models and could have caused novel gravitational effects in the early universe, although it is unclear whether the effects could be directly observed today.
The physicists have published their paper on the possibility of oscillons existing after inflation in a recent issue of Physical Review Letters. As the scientists explain in their paper, oscillons are massive, long-lived excitations of a scalar field that are localized, i.e., they do not dissipate like ripples produced by dropping a pebble in a calm pond. Instead, an oscillon switches between being a hill and a crater, alternately rising above and sinking below the spatially uniform state of the field. In previous experiments, scientists have created oscillons by vertically vibrating a plate with a sufficiently thick layer of granular particles. As long as they’re not disturbed, oscillons will continue to move up and down for hundreds of thousands of oscillations.