Albert Einstein invented a factor — his Cosmological Constant — to balance the natural force of gravity with. He later described this as his “greatest blunder”.
Ironically, this factor (often descibed as his “fudge factor” by other scientists) turns out to be — in some ways — within cooee of correct as a stretching value for the universe.
I wonder if Albert would have thought something along the lines of “Oh, blast! I was right!”