Speaker
Description
Cosmic strings can be produced during phase transitions in the very early universe. They are particularly interesting objects since they emit gravitational waves contributing to the stochastic gravitational wave background. This gives us possibility to connect gravitational waves experiments to unknown physics scenarios of the very distant past. In the early stages of cosmic string network evolution we expect frequent interactions of cosmic strings with particles of the surrounding plasma. Usually in the literature the contribution to the stochastic gravitational wave background from these friction-dominated regimes is neglected. In our work, however, we show that, for a significant part of parameter space, the inclusion of friction leads to a prominent signature in the ultra high frequency range of the spectrum. More than that, this signature should be sensitive to the particular underlying high energy physics scenarios, depending not only on the fields that constitute the string but also on the particle contents of the early universe.
