Why does a star exist as a whole body? Is it possible to imbalance the stellar matter?

The equilibrium of the star’s substance and, consequently, the existence of the star as a whole is due to the equality of the force of attraction of the substance directed towards the center and the force of gas pressure directed from the center.
The excess of the gas pressure force over the gravitational forces occurs during the explosion of a star; the opposite is true for the collapse of a star.

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