The Enterprise passes through the creation point
The creation point or galactic creation point was an area in the galactic core where matter was being created. The creation of matter at a creation point caused a phenomenon which Spock described as a matter-energy whirlwind.
In 2269, the USS Enterprise was sent on a scientific mission to find the creation point. While passing through it they were sucked into an alternate universe where magic replaced science. (TAS: "The Magicks of Megas-Tu")