Man falling into grate variation Ladder paradox

a man (represented segmented rod) falling grate

this paradox proposed , solved wolfgang rindler , involved fast walking man, represented rod, falling grate. assumed rod entirely on grate in grate frame of reference before downward acceleration begins simultaneously , equally applied each point in rod.

from perspective of grate, rod undergoes length contraction , fits grate. however, perspective of rod, grate undergoing length contraction, through seems rod long fall.

in fact, downward acceleration of rod, simultaneous in grate s frame of reference, not simultaneous in rod s frame of reference. in rod s frame of reference, bottom of front of rod first accelerated downward (not shown in drawing), , time goes by, more , more of rod subjected downward acceleration, until of rod accelerated downward. results in bending of rod in rod s frame of reference. should stressed that, since bending occurs in rod s rest frame, true physical distortion of rod cause stresses occur in rod.