The World 'Out there' is an Experience Displayed 'In here':

The young deity Rohitassa once asked the Buddha:
Sir, is it possible - by travelling - to reach, see & know an end of the world,
where one is not born, do not age, do not die, do not pass on, & is not reborn?

The exalted Buddha answered:
That end of the world, where one neither is born, nor ages, nor dies,
nor is reborn, cannot ever be reached, known, or seen by travelling...
However, friend, I say that without reaching the end of the world,
there cannot be any end of Suffering...
It is just here within this 2 meters long carcass, endowed with conscious
experience, that the world emerges, manifests, ceases, and the Way
leading to its cessation is developed, completed and made known...
Therefore, knowing this world to be thus, the intelligent one reach the
end of the world, by completing the Noble life. Having directly known
the world's end, at ease & in peace, there remains no longing for this or
any other world...!


This seems IMHO the most profound and far reaching statement in
human history so far... The world start & ends within this very frame
of a conscious corpse... 600 years later the 'Mind-Only' idealists
took this to the extreme by declaring: 'All is Empty'..., which -though
captivating-, leads nowhere, except ever deeper into the entangling
jungle of speculative views... This subtle and deep middle view of a
mirror world, created by observing it, is only seen by the Buddha...!

See also the ALL as the Sensed Source:

Source: The Connected Discourses of the Buddha. Samyutta Nikāya I 62

The physical world 'out there' is an internal mental representation!