Let me define first, what is meant by Reincarnation and Rebirth
in this topic so as not to be confused.
Reincarnation means a soul, an ego - being permanent - becomes
reincarnated elsewhere.
In Buddhism, under the light of the doctrine of No-self, and
through meditation we will find out that there is no such thing as
a permanent self, an ego, that undergoes reincarnation. That all
along is an illusion, and it is because of that illusion, we are
being stuck on samara and being reborn in the samsaric
planes.
Life (Self) is nothing other than
the continuous flow of the Now Moment.
The Now Moment ceases as it arises. This moment must completely
ceased
and serves as the CAUSE for the next moment to arise.
Therefore Self is a process of series Self1, Self2, Self3,
Self4, Self5, Self6...etc
A fixed entity 'Self' does not exist, what really exists is a
momentary Self.
Under deep meditation, one is able to observe and sense the karmic
and mental factors from moment to moment,
it is these factors that are succeeded from moment to moment and
life and life but not a fixed entity.
When the karmic and mental factors subsides, it is known as "The
True and Only (and Inherently egoless) Conscious Light
(Itself)".
- Thusness
What is Rebirth? It is very simple, in fact rebirth happens every
moment, ever instant, now. Rebirth happens every moment in our
life.
Rebirth is a nature of Reality - that everything
is in a constant flux, impermanent, without a self. It is
impossible to say that Humans reborn, then Gods or Buddhas
reincarnate. There is no such thing. Secondly, Gods in Buddhism
still belong to the 6 realms of Samsara, undergoing rebirth in the
samsaric planes.
All mainstream authentic Buddhism, including Tibetan Buddhism,
does not hold on the false idea of an 'atman' undergoing
reincarnation.
Sometimes you may find 'Reincarnation' mentioned in Buddhist books,
but it really means 'rebirth'. It is because many people oversee
the difference between these two terms.
Due to illusion, our egoic consciousness (7th consciousness) is
reborn again, but this rebirth consciousness is also conditioned
arising, empty.