What mechanism is responsible for increasing the distance between distant galaxy clusters?

Answer

The stretching of the fabric of space-time itself.

The separation between galaxy clusters is caused by the expansion of the universe, which stretches the space-time fabric between them, analogous to rising dough carrying embedded peppercorns apart.

What mechanism is responsible for increasing the distance between distant galaxy clusters?

#Videos

If the Universe is expanding, then why do galaxies collide? - YouTube

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