You Are Here (In The Universe) - Minkowski Diagrams

Every one of us is located in our own personal world-point in terms of space, time and space-time.
A spacetime diagram, often called a Minkowski diagram, is a geometric representation of motions in spacetime. The vertical axis is usually plotted as the time axis (and normally one uses ct for this axis, so that one has conventional units of distance on all axes and light will make a 45° path). Depending upon the situation one sometimes plots a single spatial dimension, or two spatial dimensions (real spacetime has three spatial dimensions, but these cannot be represented along with the one time dimension in ordinary 3D drawings). Any point in spacetime is called a world point, and a series of worldpoints representing the motion of some object is called a world line.

If ct is used for the time axis, then light on a Minkowski diagram will always travel at 45° to the time axis (either right or left at 45° in a one spatial direction Minkowski diagram, along the surfaces of a 45° cone - called the light cone - in a dual spatial dimension Minkowski diagram.
Tony says:  We all have our allocated world-point and notch in space-time. Make the best of it and leave it as you found it or better for the next occupants. Warmongering upsets the natural balance of the universe and the cosmos. Yes, I am trying to make my interest in these matters relevant to this site.  Einstein would have endorsed my point of view. He would have bought me a drink.