Poutnik wrote:
Hello,

I have noticed there is quite a lot of different star behaviours.

Are the star properties and behaviour
more or less determined by initial mass and evolution stage ?

To a first approximation, yes. This is the essence of the Russell-Vogt
theorem, that a star's initial mass determines its subsequent evolution.


Or are there a parallel evolution paths possible ?

There can be some variations due to differences in composition (producing
differences in opacity of material), initial rate of rotation, magnetic
fields, and presence in a (close) binary system.


I suppose being in binary system
can create other dimension to variability.

How much is eventually in this context significant
difference in initial composition,
like stars of the 1st generation with initial cosmological
composition, versus later generations with some extra helium and
heavier elements ?

Go back and review in textbooks the studies of cluster colour-magnitude
diagrams for population I and population II, which have differences due to
composition and age.

--
Mike Dworetsky

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