According to our current understanding of physics based on Einstein's theory of relativity, it is not possible for an object with mass to travel at or exceed the speed of light in a vacuum. This is due to several fundamental principles.
Firstly, as an object with mass accelerates, its energy increases, and as it approaches the speed of light, its energy approaches infinity. To accelerate an object with mass to the speed of light would require an infinite amount of energy, which is not feasible.
Secondly, as an object with mass approaches the speed of light, its mass also increases. This phenomenon is known as relativistic mass increase. As the object's mass increases, more and more energy is required to further accelerate it, making it increasingly difficult to reach or exceed the speed of light.
Additionally, as an object with mass accelerates close to the speed of light, time dilation and length contraction occur. Time dilation means that time appears to pass more slowly for the moving object relative to a stationary observer. Length contraction means that the object appears to shorten in the direction of its motion. These effects are a consequence of the relativistic nature of spacetime and are well-established by experimental evidence.
Given these principles, it is currently believed that anything with mass cannot achieve or exceed the speed of light. However, it's important to note that our understanding of physics is always evolving, and future discoveries or theories may bring new insights that challenge or refine our current understanding.