Zobrazeno 1 - 10
of 1 470
pro vyhledávání: '"Chung, Daniel"'
Autor:
Chung, Daniel J. H., Sudhir, Nidhi
Particle production in cosmology is often efficiently computed in terms of Bogoliubov transforms. Restricting to a particular class of dispersion relationships, we identify a map between the number of particles produced in a special kinematic limit a
Externí odkaz:
http://arxiv.org/abs/2408.11452
We investigate nonlinear energy transfer for channel flows at friction Reynolds numbers of $Re_{\tau}=180$ and $590$. The key feature of the analysis is that we introduce a new variable, which quantifies the energy transferred from a source mode to a
Externí odkaz:
http://arxiv.org/abs/2408.05062
One well known method of generating a large blue spectral index for axionic isocurvature perturbations is through a flat direction not having a quartic potential term for the radial partner of the axion field. In this work, we show how one can obtain
Externí odkaz:
http://arxiv.org/abs/2406.12976
To aid in prediction of turbulent boundary layer flows over rough surfaces, a new model is proposed to estimate hydrodynamic roughness based solely on geometric surface information. The model is based on a fluid-mechanics motivated geometric paramete
Externí odkaz:
http://arxiv.org/abs/2406.05062
Large blue tilted spectral index axionic isocurvature perturbations can be produced when the axion sector is far out of equilibrium during inflation through an initial Peccei-Quinn (PQ) symmetry breaking field displacement along a nearly flat directi
Externí odkaz:
http://arxiv.org/abs/2309.17010
Autor:
Li, Mogeng, de Silva, Charitha M., Chung, Daniel, Pullin, Dale I., Marusic, Ivan, Hutchins, Nicholas
Publikováno v:
Journal of Fluid Mechanics, 923, A18 (2021)
This study presents an experimental dataset documenting the evolution of a turbulent boundary layer downstream of a rough-to-smooth surface transition. To investigate the effect of upstream flow conditions, two groups of experiments are conducted. Fo
Externí odkaz:
http://arxiv.org/abs/2308.02890
Autor:
Li, Mogeng, de Silva, Charitha M., Rouhi, Amirreza, Baidya, Rio, Chung, Daniel, Marusic, Ivan, Hutchins, Nicholas
Publikováno v:
Journal of Fluid Mechanics, 872, 472-491 (2019)
This paper examines recovery of the wall-shear stress of a turbulent boundary layer that has undergone a sudden transition from a rough to a smooth surface. Early works of Antonia and Luxton questioned the reliability of standard smooth-wall methods
Externí odkaz:
http://arxiv.org/abs/2308.01777
Isocurvature perturbations with a blue power spectrum are one of the natural targets for the future large scale structure observations which are probing shorter length scales with greater accuracy. We present a Fisher forecast for the Euclid and Mega
Externí odkaz:
http://arxiv.org/abs/2306.09456
Previous numerical investigations of gravitational particle production during the coherent oscillation period of inflation displayed unexplained fluctuations in the spectral density of the produced particles. We argue that these features are due to t
Externí odkaz:
http://arxiv.org/abs/2209.01713