Forget a cricket ball, the reason even a perfect sphere moving at speed, when given a little wobble, can move laterally even on almost still air is 'Magnus Effect'. In simple terms, the thing is that even when the air is almost static, a moving ball makes the air around it move a bit. And when there's a slight wobble (or rotation) in the moving ball the air around it moves in a way to exert a lateral force on it. [QUOTE/]
Magnus effect - Wikipedia, the free encyclopedia
No it cannot be the Magnus Effect: this is quite easy to understand and simply the horizontal rotation of a ball such as a footie dragging air eg as beckham takes a corner it 'veers' away.. but horizontal rotation is nothing to do with cricket ball swing- the ball is only spinning on a vertical axis. The ammount a crix ball is spinning too I dont think has any major significance either, afaict, completely converse to the Magnus where ammount of 'veer' is absolutely dependent on ammount of spin.
Well someone show me Harmison bowling with the seam angled 'cos I dont remember his action as anything but the way most bowlers do and that's seam straight so allowing the shine to swing the ball/ seam angle need not be used (its a difficult thing to get correct) I remember him same as most bowlers, for eg the great Glen McGrath who swung it consistantly and always always with the seam dead-stock-straight-up. Few bowl with such an exaggerated angled seam as JA.. Hoggard is the only one I can think of: both a bit freaky compared to most. Even his 'worst delivery of all time' he fired down seam dead upright w'out angle: something acted on that brand new ball to make it go from wkt to wkt then divert wildly to 2nd slip and Im still unable to put my finger on what exactly.