Theory of time travel . Maybe there is a time traveller among us !?

It is unlikely that time is linear, we might be traveling through a series of related moments which appear linear to us but which in reality are in motion all around us like small bits of sand being swirled in water. We only believe our individual linear motion is correct. In fact the people around us may already not be on the same exact time track as us. We only perceive it as such because they have to be here in order for this moment to occur, in a short while they are replaced by a nearly identical individual on a slightly different track. It may even be that there are time effects on our memories so we cannot possibly perceive any differences as we travel through time. If this is true, the Grandfather paradox would still hold, only it would be impossible to determine which of a series on infinite identical and nearly identical grandfathers was yours.