Space and time are the only things in this physics engine called Source. (Not HL2 Source, but Source as in the Source of all life.) The 3D physics engine relies on both space and time constants and to teleport, you use the cheat console of 3D to skip the processing of either space or time and you can teleport or time travel.
Removing the constant of space is what makes time travel possible and removing the constant of space is what makes teleportation possible.
Here's a video describing in more detail, Einstein's theory of relativity and how you can apply that to what I just said.