I will present a toned-down version of Heidegger's existentialism here:
The meaning of our being is the ability to know that our being will end.
This means that we take seriously our limited being and thus our indebtedness to care for others.
Has matter ever become self aware?
Realizing our limited time upon the earth is the kind of self-awareness that (most) other animals
seem to lack; We gain this with the ability to create a theoretical world we've never seen.
My sense, however, is that there is a stage beyond this, where the sense of a self that is aware disappears and there is only awareness.
This is exactly the awareness that is consciousness. To realize that being is more than the the self responding the biological impulses, but rather authentic care for the 'greater self' that is shared in answerability for our fellow man.
t and dimension can a biological being perceive. Our awareness, it seems to me, depends on our organs of perception and that the evolution of awareness depends on need
Absolutely. We are biological entities developed with the traits needed to perpetuate the replication of our particular formation of DNA. The concept of 'matter' only matters at this level of 'energy congealed' (as that IS the definition of matter). We might see 'energy congealed' at many other levels as well, levels our DNA doesn't exist and, and for which we only have the slightest shadow of an inclination.
Consider that the majority of matter is dark matter; why do we think that OUR matter is superior matter? It's just different, and in fact the minority, in comparison to the universe of Dark Matter. It seems asinine to argue that dark-matter can't have its own universe of salient newtonian-level physics that allows it perpetuate patterns of combination via adaptation.
That matter may or may not suffer the entropy that we do; may or may not know or care about our existence, and so forth.
Who are we if not our name, our job, our sexuality, etc.
None of those form Identity directly. It is alterity, the being alternate to, that forms identity.
your name is "Not" a X-ethinciity name, X-brother's name, etc; your job is NOT a low-class job, is NOT an investment banker, etc; your sexuality is not homosexual, is not bisexual, etc; and so forth.
It is in spliting ourselves from what we are not that we define our selves as different. When we drop this farce of difference we open ourselves to being indebted to the spirit of others.