Is Claude Allegre a top physicist?

No. All�gre is making a rookie error. The topic of air resistance in trajectories of falling objects is common in first year physics courses and more sophisticated treatments such as the Stokes equation follow in later years. It doesn't take a Nobel prize winner to correct All�gre, any competent physics undergrad can spot the error. Perhaps All�gre knew better in his ealier years, but now he only tarnishes his reputation by making elemenary errors. He should rest on his laurels, and enjoy French wine in his twilight years.