What do Hindu texts say about Multiverse?

 An image Lord Vishnu shows him sleeping and there are lots of bubbles around him and each of these bubbles represent universes. 

What the Western scientists had
discovered in the 19th century, and
which our 21st-century eminent scientists
like Stephen Hawking and Dr Michio
Kaku
have now affirmed and corroborate, is a
twice-told tale for the great majority of
the Hindus. That there are multiple or
innumerable universes is no news to the
Hindu who is learned in the Hindu
scriptures. Not just one but
several Puranas, viz., Vishnu Purana,
Srimad Bhagavatam, Padma Purana and
Vayu Purana, and authoritative Hindu
scriptures like Atharva Veda have spoken
of the different universes.

Every universe is covered by seven layers
— earth, water, fire, air, sky, the total
energy and false ego — each ten times
greater than the previous one. There are
innumerable universes besides this one,
and although they are unlimitedly large,
they move about like atoms in You.
Therefore You are called unlimited
( Srimad Bhagavatam 6.16.37 )