The Omniverse website asks us to apply for early access for the PhysX 5 SDK, but there is no further information or clues on how to go about doing this. If this is aimed specifically at companies rather than individuals, they should probably state so on the website.
The website very clearly makes it sound like we can access the PhysX 5 SDK by downloading and installing Omniverse, which is absolutely not true. If this is a ploy to attract developers to download Omniverse, it is a very bad idea. It will only serve to annoy the developers that are looking for the SDK. If the SDK is not yet available to the public, it should clearly say so.
Hello @xmoatz. PhysX 5 is apart of Omniverse and is accessible to the public through Omniverse. Here is a link to what is currently available: Physics Core
That documentation focuses on interacting with the Physics extension through the Omniverse user interface. However, you may setup and interact with physics components also via the Python API, see Help > Physics Scripting Manual and the source code for the snippets and samples in Window > Simulation > Demo Scenes .