Climate modellers have created a plausible reality, not reality, says Nick M at Counting Cats.
Mathematics is an incredible toolbox and whilst it can be used to understand reality it can also be used to create new realities. For example it is entirely possible - indeed quite easy - to build a model of the solar system and then subtract Jupiter. The same perturbed Keplerian orbits pertain and the laws of motion and gravity are not changed because there is nothing in them to say “A gas giant must exist between Mars and Saturn”.
(H/T Chuckles)