Anti-invariant semi-riemannian submersions from almost para-hermitian manifolds

We introduce anti-invariant semi-riemannian submersions from almost para-hermitian manifolds onto semi-riemannian manifolds. we give an example,investigate the geometry of foliations which are arisen from the definition of a semi-riemannian submersion,and check the harmonicity of such submersions. we also obtain curvature relations between the base manifold and the total manifold. © 2013 yilmaz gündüzalp.