Editing Knuckleball (section)

==Physics==
The erratic movement of knuckleballs is of interest of study in the field of [[fluid dynamics]]. It is widely believed that the "knuckling" behavior is caused by [[laminar–turbulent transition]], as the [[Reynolds number]] of most knuckleballs is usually near the critical Reynolds number for spherical objects.<ref>{{cite journal|last1=Higuchi |first1=Hiroshi |last2=Kiura |first2=Toshiro |date=2012 |title=Aerodynamics of knuckle ball: Flow-structure interaction problem on a pitched baseball without spin |url=https://www.sciencedirect.com/science/article/abs/pii/S088997461200028X |journal=Journal of Fluids and Structures |volume=32 |pages=65–77|doi=10.1016/j.jfluidstructs.2012.01.004 |bibcode=2012JFS....32...65H }}</ref>

The seams of a baseball have been shown to affect the separation of the [[boundary layer]] of air around a baseball, contributing to knuckleball movement.<ref>{{cite journal| last1=Borg |first1=John|last2=Morrissey|first2=Michael|date=2014|title=Aerodynamics of the knuckleball pitch: Experimental measurements on slowly rotating baseballs |url=https://baseball.physics.illinois.edu/KBall/Borg-AJP-Oct14.pdf |journal=American Journal of Physics |volume=82 |issue=10 |pages=921–927|doi=10.1119/1.4885341 |bibcode=2014AmJPh..82..921B }}</ref> However, "knuckling" behavior has also been observed in perfectly-spherical and smooth [[steel]] beads.<ref>{{cite news |last=American Physical Society's Division of Fluid Dynamics |date=November 2012 |title=What's behind the success of the soccer 'knuckleball' |url=https://www.sciencedaily.com/releases/2012/11/121116085201.htm}}</ref>