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The defining characteristic of a Black Hole is its extreme gravitational field. Zero gravitational field would make it indistinguishable from empty space. A Black Hole with zero gravity would not trap anything and would be scientifically meaningless. A moderate gravitational field like Earth allows objects including light to escape easily. Earth's escape velocity is only 11.2 km/s which is far below the speed of light. Black Holes have escape velocities exceeding the speed of light which is fundamentally different. A Black Hole forms when a massive star collapses at the end of its life. The resulting object has such extreme density that the escape velocity at and within the event horizon exceeds the speed of light (3 x 10 to the power 8 m/s). Since nothing can travel faster than light according to special relativity nothing including light itself can escape from within the event horizon. This makes Black Holes invisible to direct observation. Black Holes do not repel matter. They have intense attractive gravitational fields that pull everything toward them including gas dust stars and even light.
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Heat is a form of energy that transfers between objects or systems due to a temperature difference, moving from a hotter body to a cooler one until thermal equilibrium is reached.
