Antimatter universe An antimatter universe , also known as a negative universe , was a type of parallel universe on a different dimension al plane . These universes were the negative antimatter opposites of the familiar positive matter universe s . While in the prime universe things were composed of matter , the corresponding things in the negative universes were composed of antimatter . In general though , matter from a positive universe coming into contact with antimatter from a negative universe would not result in the annihilation of both particles . ( ; ) Minus universe . The minus universe was the home of , a man whose civilization created a negative magnetic corridor to safely connect with the positive matter universe . The universes closely resembled each other , identical particle s , individuals and planet s existed in both universes , where one was composed of matter , the corresponding other was composed of antimatter . Only if the exact identical particle counterparts from the different universes came into contact inside either universe they would annihilate each other . This would start a chain reaction that would annihilate the universe , where the event took place , as a whole . As long as this type of contact was averted , safe visitations could be made . Within the negative magnetic corridor , an alternative warp allowed safe interaction with counterpart elements of both universes . If a person with a counterpart were to step through to either side together , only one entity would exist . The entity would periodically change places with its counterpart distorting the physical laws of that universe while the change occurred . The effect included , for a split second , the complete disruption of normal magnetic and gravimetric field s , time warp distortion , and radiation variations . Magnetic field s nullified , dilithium crystal s were quickly drained of power , and mass attained zero gravity . This event occurred when anti - Lazarus stepped through in 2267 . ( ) Reverse universe . In 2270 , while transporting Commodore Robert April to his retirement ceremony on Babel , attempted to stop an alien starship heading for the Beta Niobe supernova at warp 36 . While trying to rescue the ship , the " Enterprise " was dragged inside the nova and into the reverse universe . In the reverse universe , the inhabitants of the planet began their life at an old age and slowly grew younger . Brain functions , language , and operational controls worked in reverse of what they did in the positive matter universe , as the flow of time was reversed . Beginning a process ended it and starting it stopped it . Space was white and full of black stars . Although the universes had totally different timelines , the planets and stars of the Milky Way Galaxy were at least located in exactly the same places . During a short visit to the reverse universe lifeforms would grow younger at a normal but reverse rate . Spending more time in this dimensional realm , the rate of reverse growth increased to a rate where lifeforms would reverse grow to infants from adulthood within minutes and die in reverse birth . It was possible to use molecular structure records in the transporter system to restore the physical age though . ( )