HealzDevo- let me illustrate with a Gedankenexperiment (Einsteins) imagine an elevator with an infinitely long shaft. the elevator is accelerated up the shaft at a constant rate, say 9.8 m/s squared. inside the elevator there are no windows and the occupants cannot see any of the exterior world. Fred jumps up, rises for a time and then returns to the floor. Fred holds a ball in his hand which he releases. the ball falls to the floor. Fred turns to his class and announces the effect of an invisible gravitational field. from the outside of the elevator the truth is obvious. Fred accelerated away from the floor but the elevator also accelerating catches up to him and smacks him in the feet. The released ball remains stationary while the elevator floor catches up with it until the floor smacks the ball. More importantly to our Gedankenexperiment is that Fred moves to the far wall of the elevator, takes out a flash light and shines it toward the opposite wall. the light beam leaves the flashlight and begins its journey toward the opposite wall. during the time it takes the beam to cover this distance the elevator has moved upward. the beam strikes the wall at a lower point than the one it was aimed at. Increasing the acceleration of the elevator moves this strike point even further down the wall. Look Fred exclaims gravity can bend a light beam. Since so called gravitational fields are indistinguishable from an accelerated system, gravity is not a true force any more than centrifugal force. Masses warp the spacetime continum and objects and light beams follow the warped fabric of spacetime. No force required.
that the speed of light in a vacuum is a constant to all observers is a relativistic effect that speed has on the fabric of spacetime and massenergy so that the very things that we use to measure speed, distance and time are altered TO SOMEONE NOT IN THAT REFERENCE FRAME. to those in the reference frame all is normal, it is the observers frame of reference that is distorted
Einstein did not ignore the atomic world it operates by its own rules which Einstein could never accept "God does not play dice with the universe"
Blackholes are a concept that extends relativity into a singularity of infinite mass, zero volume, and zero time. since our system of mathematics has division by zero as an undefined function all bets are off but because of these very same relativistic effects it would take a black hole infinite time to form