Isaac Newton and Albert Einstein had different views regarding the nature of light and its behavior. Newton's theory of light, proposed in the 17th century, described light as a stream of particles called corpuscles. He believed that light traveled in straight lines and that its speed was constant in a given medium. However, he did not provide a specific value for the speed of light.
On the other hand, Albert Einstein's theory of relativity, developed in the early 20th century, presented a different understanding of light. According to Einstein's theory, light behaves as both particles (photons) and waves, known as the wave-particle duality. Einstein's theory of special relativity, in particular, established that the speed of light in a vacuum is constant and is approximately 299,792,458 meters per second (or about 186,282 miles per second).
So, in terms of the speed of light, Newton and Einstein had differing perspectives. Newton did not provide a specific value for the speed of light, whereas Einstein's theory of relativity established that the speed of light in a vacuum is a fundamental constant.
In terms of who is correct, the scientific consensus overwhelmingly supports Einstein's theory of relativity. Numerous experimental observations and measurements have confirmed the constancy of the speed of light as predicted by Einstein's theory. This fundamental principle underpins much of modern physics and has been validated by a vast array of experiments and empirical evidence.
While Newton's theories and contributions to physics were groundbreaking in their time and still applicable in many contexts, Einstein's theory of relativity has shown remarkable accuracy and predictive power, especially in the realm of high-speed objects and gravitational fields. It's important to note that scientific theories are constantly subject to testing and refinement, but as of now, Einstein's theory of relativity remains the accepted framework for understanding the behavior of light and its relationship to space and time.