When can you go to the distortion world in platinum?

You can access the Distortion World in Pokémon Platinum after you have defeated the Galactic Admins at the Veilstone Game Corner. This happens after you have obtained the Fourth Gym Badge.

Here's a more detailed breakdown:

1. Defeat the Galactic Admins: After obtaining the Fourth Gym Badge, you will encounter the Galactic Admins at the Veilstone Game Corner.

2. Enter the Distortion World: After defeating them, they will attempt to escape through a portal to the Distortion World. You can follow them through this portal, which will grant you access to this unique area.

Important Note: The Distortion World is only accessible during this specific point in the game and is not a repeatable area.