Which statement concerning black hole masses and Schwarzschild radii is not true?

The statement regarding the Schwarzschild radius and its relationship with black hole masses is fundamentally about the defining characteristics of black holes from a physics perspective. The Schwarzschild radius, which represents the radius of the event horizon surrounding a black hole, is intrinsically linked to the mass of the black hole itself.

When it comes to the relationship between mass and Schwarzschild radius, the formula is directly proportional, meaning that a black hole's event horizon is determined only by its mass and not influenced by external factors. This means that once a black hole is formed, its Schwarzschild radius is fixed based on its own mass, regardless of any other objects or masses present in the surrounding environment.

Therefore, any changes in the mass of external objects or the presence of nearby objects do not impact the already existing Schwarzschild radius of the black hole. Each black hole's characteristics, including its event horizon, are properties of the black hole alone, and not affected by external masses. This understanding clarifies why the statement about the Schwarzschild radius changing based on the mass of external objects cannot be true.