6533b82afe1ef96bd128b87a

RESEARCH PRODUCT

The varieties of bifocal Grassmann tensors

Marina BertoliniGilberto BiniCristina Turrini

subject

Mathematics - Algebraic GeometryMulti-view Geometry · Grassmann Tensors · Fundamental Matrices ·Group ActionsApplied MathematicsFOS: MathematicsSettore MAT/03 - GeometriaAlgebraic Geometry (math.AG)

description

AbstractGrassmann tensors arise from classical problems of scene reconstruction in computer vision. In particular, bifocal Grassmann tensors, related to a pair of projections from a projective space onto view spaces of varying dimensions, generalize the classical notion of fundamental matrices. In this paper, we study in full generality the variety of bifocal Grassmann tensors focusing on its birational geometry. To carry out this analysis, every object of multi-view geometry is described both from an algebraic and geometric point of view, e.g., the duality between the view spaces, and the space of rays is explicitly described via polarity. Next, we deal with the moduli of bifocal Grassmann tensors, thus showing that this variety is both birational to a suitable homogeneous space and endowed with a dominant rational map to a Grassmannian.

10.1007/s10231-023-01317-yhttps://hdl.handle.net/10447/588112