Abstract: In this talk which is based on the joint work with Kentaro Saji given in , taking into account the Legendrian dualities in  which are extensions of the Legendrian dualities in , we first introduce new extended Legendrian dualities for the 3-dimensional pseudo-spheres of various radii in Lorentz-Minkowski 4-space. Secondly, by connecting all of these Legendrian dualities continuously, we construct Legendrian dual surfaces (lying in these 3-dimensional pseudo-spheres) of a spacelike curve in the 3-dimensional lightcone. Finally, we investigate the singularities of these surfaces and show the dualities of the singularities of a certain class of such a surface in the 3-dimensional lightcone.
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-  K. Saji, H. Yildirim, Legendrian dual surfaces of a spacelike curve in the 3-dimensional lightcone, Journal of Geometry and Physics, 104593, https://doi.org/10.1016/j.geomphys.2022.104593