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Internal gravity waves (IGWs) are naturally produced by convection in stellar envelopes, and they could be an important mechanism for transporting angular momentum in the radiative interiors of stars. Prior work has established that they could operate over a short enough time scale to explain the internal solar rotation as a function of depth. We demonstrate that the natural action of IGWs is to produce large scale oscillations in the solar rotation as a function of depth, which is in marked contrast to the nearly uniform rotation in the outer radiative envelope of the Sun. An additional angular momentum transport mechanism is therefore required, and neither molecular nor shear-induced turbulent viscosity is sufficient to smooth out the profile. Magnetic processes, such as the Tayler-Spruit dynamo, could flatten the rotation profile. We therefore conclude that IGWs must operate in conjunction with magnetic angular momentum transport processes if they operate at all. Furthermore, both classes of mechanisms must be inhibited to some degree by mean molecular weight gradients in order to explain the recent evidence for a rapidly rotating embedded core in the Sun.
The latitudinal distributions of the yearly mean rotation rates measured respectively by Suzuki in 1998 and 2012 and Pulkkinen $&$ Tuominen in 1998 are utilized to investigate internal-cycle variation of solar differential rotation. The rotation rate
Recent photometric observations of massive stars show ubiquitous low-frequency red-noise variability, which has been interpreted as internal gravity waves (IGWs). Simulations of IGWs generated by convection show smooth surface wave spectra, qualitati
The rotation rates in the deep interior and at the surface of 22 main-sequence stars with masses between $1.0$ and $1.6,{rm M}_{odot}$ are constrained by combining asteroseismological analysis with spectroscopic measurements. The asteroseismic data o
Detailed modeling of stellar evolution requires a better understanding of the (magneto-)hydrodynamic processes which mix chemical elements and transport angular momentum. Understanding these pro- cesses is crucial if we are to accurately interpret ob
We present numerical simulations of internal gravity waves (IGW) in a star with a convective core and extended radiative envelope. We report on amplitudes, spectra, dissipation and consequent angular momentum transport by such waves. We find that the