Herr Einstein was my idol, my longing, when I became a high school student about 38 years ago, still he is shining on me now.
Who did gaze at the abstract property and abstract essence of this empty space and elusive time in his era?
He did give body and substance to the physical nuance of the Lorentz transformation that dictates the relative relationship of physical variables seen from relatively moving frames! And he did at the end find the equality of energy and mass! Oh, what a great triumph he did make!
Although he was not able to show his enough understanding regarding microscopic physics, that is, quantum mechanics, his concerns to macroscopic concepts like space, mass, time, gravity, and energy are still now introducing me to unknown world of physics.
Let's go to the place where we can think, speculate, ponder, wonder, and meditate about the various basic physical concepts! Let's enjoy thinking about this empty vacuum space itself alone! What is mass? What is time? What is electric charge? How do the relativistic theory and the quantum mechanics match with each other?
Oh, what a plenty amount of puzzles this world is filled with!