As early as the 17th century, the great Italian physicist Galileo conducted his famous free fall experiment at the Leaning Tower of Pisa, proving that regardless of an object's weight, they fall at the same acceleration in a vacuum. However, over 300 years later, a research team led by American physicist Fishbach discovered that objects of different masses actually fall at different speeds in a vacuum. This sparked a significant controversy in the scientific community regarding the potential existence of a fifth force in the universe—a possible repulsive force that operates only over limited distances, counteracting some of the gravitational pull.
Fishbach hypothesized that this force might exist in the form of "supercharge," affecting the falling speed of objects, especially when their binding energies differ. Many scientists began conducting various experiments to test this hypothesis, including using advanced laser technology to monitor the falling speeds of objects, and even conducting experiments near cliffs in Colorado, USA. However, scientists generally believe that proving this theory requires overcoming numerous complex factors and external interferences.
