According to our current understanding of physics, the fundamental reason why the speed of light cannot be broken is rooted in the structure of spacetime and the nature of causality. The speed of light, denoted by 'c', plays a critical role in the theory of special relativity, proposed by Albert Einstein.
In special relativity, the speed of light is considered to be an invariant quantity, meaning it has the same value in all inertial reference frames. This postulate is supported by a large body of experimental evidence. The constancy of the speed of light leads to several important consequences:
Time dilation: As an object accelerates and approaches the speed of light, time dilation occurs. This means that time appears to slow down for the moving object relative to a stationary observer. The closer an object's speed gets to the speed of light, the greater the time dilation effect. This phenomenon is a fundamental consequence of the geometry of spacetime and is a direct consequence of the constancy of the speed of light.
Length contraction: Another consequence of the constancy of the speed of light is length contraction. As an object moves at relativistic speeds, its length appears to contract in the direction of motion as observed by a stationary observer. Again, this effect becomes more pronounced as the object's speed approaches the speed of light.
Causality and information transfer: The constancy of the speed of light is intimately tied to the preservation of causality in our universe. It ensures that cause and effect relationships are preserved and that no information can be transmitted faster than the speed of light. If an object were to travel faster than light, it would violate the causal structure of spacetime and allow for potential paradoxes and violations of causality.
It's important to note that the notion of the universe "wanting" or "preserving" the upper barrier on the speed of light is more of a conceptual interpretation rather than a literal characteristic of the universe. The constancy of the speed of light is a fundamental property of our reality as described by our best scientific theories. It is not a deliberate decision or preference of the universe, but rather a consequence of the laws of physics as we currently understand them.
It's worth mentioning that there are speculative theories, such as wormholes or warp drives, that explore the possibility of bypassing the speed of light limitation. However, these ideas remain speculative and are not currently supported by experimental evidence or widely accepted by the scientific community.