According to our current understanding of physics, light always travels at a constant speed in a vacuum, denoted by "c," which is approximately 299,792,458 meters per second. This value is considered the maximum speed limit in the universe. It is a fundamental constant in the theory of special relativity proposed by Albert Einstein.
Based on this theory, as an object with mass approaches the speed of light, its energy and momentum increase infinitely. Thus, it requires an infinite amount of energy to accelerate an object with mass to the speed of light. As a result, particles with mass, including photons (particles of light), cannot surpass the speed of light.
If, hypothetically, an object could exceed the speed of light, it would violate the principles of special relativity. According to these principles, as an object with mass approaches the speed of light, its relativistic mass increases, and its time dilation and length contraction effects become significant. Therefore, exceeding the speed of light would have profound consequences on the fundamental laws of physics.
As for visibility, light is the range of electromagnetic waves that we can perceive with our eyes. Visible light has a specific range of wavelengths, approximately 400 to 700 nanometers. If an object were to travel faster than light, it would, in theory, move beyond the range of visible light, making it invisible to our eyes.
However, it's important to note that the concept of exceeding the speed of light is purely hypothetical at this point, as it contradicts our current scientific understanding.