Cosmic F- and D-strings from pure Yang-Mills theory
  We discuss the formation of cosmic strings or macroscopic color flux tubes
after the deconfinement/confinement phase transition in the pure Yang-Mills
theory. Based on holographic dual descriptions, these cosmic strings can be
interpreted as fundamental (F-) strings or wrapped D-branes (which we call as
D-strings) in the gravity side, depending on the structure of the gauge group.
In fact, the reconnection probabilities of the F- and D-strings are suppressed
by factors of $1/N^2$ and $e^{-c N}$, where $c = \mathcal{O}(1)$, in a
large-$N$ limit, respectively. Supported by the picture of electric-magnetic
duality, we discuss that color flux tubes form after the
deconfinement/confinement phase transition, just like the formation of local
cosmic strings after spontaneous symmetry breaking in the weak-U(1) gauge
theory. We use an extended velocity-dependent one-scale model to describe the
dynamics of the string network and calculate the gravitational wave signals
from string loops.
