The following is an excerpt from the teachings of Sri Ramana Maharshi.
The mind is a wondrous power residing in the Self. It causes all
thoughts to arise. Apart from thoughts, there is no such thing as
mind. Therefore, thought is the nature of mind. Apart from thoughts,
there is no independent entity called the world. In deep sleep there
are no thoughts, and there is no world. In the states of waking and
dream, there are thoughts, and there is a world also.
That which rises as ‘I’ in the body is the mind. If one inquires as to
where in the body the thought ‘I’ rises first, one would discover that
it rises in the Heart. That is the place of the mind’s origin. Even if
one thinks constantly ‘I’, ‘I’, one will be led to that place. Of all
the thoughts that arise in the mind, the ‘I’ thought is the first. It
is only after the rise of the “I-thought” that other thoughts occur.
The thought ‘who am I?’ will destroy all other thoughts, and like the
stick used for stirring the funeral pyre, it will itself be burnt up
in the end. Then, there will be Self-realization. When other thoughts
arise, one should not pursue them but should diligently inquire: ‘To
whom do they occur?’ It does not matter how many thoughts arise. As
each thought arises, one should inquire with alertness, “To whom has
this thought arisen?” The answer that would emerge would be “to me”.
Thereupon if one inquires “Who am I?” the mind will go back to its
source; and the thought that arose will subside.
With repeated practice in this manner, the mind will develop the power
to stay in its source. When the mind that is subtle goes out through
the brain and the sense organs, the gross names and forms appear; when
it stays in the heart, the names and forms disappear. Not letting the
mind go out, but retaining it in the Heart is what is called
“inwardness”. Letting the mind go out of the Heart is known as
“externalisation”. Thus, when the mind stays in the Heart, the ‘I’
which is the source of all thoughts will go, and the Self which ever
exists will shine.
Coming to the question - Can we see god after death as per Advaitha?, we have to understand that having visions of various forms of God like, Sri Rama, Vishnu, Shiva, Shakti, Ganapati, etc, is the result of severe austerities on the part of the spiritual aspirant, at some point of time, before Self Realisation.
So having vision of some form of God, is not the finality. If that was the case why Sri Ramakrishna continued his austeries, even after having the vision of Kali?
Self Realisation in other words is called the attaining of the state of advaita or non-duality. When this stage has finally been achieved, where is the question of worrying about having vision of the God after death?