For hundreds of years, there has been an interesting question: can light, something we see every day, be altered by gravity? This may seem like an abstract question, but it involves a deep understanding of how the world works. From Newton's classical physics to Einstein's epoch-making general theory of relativity, the study of this topic reflects not only the development of physics, but also our views on time, space, and gravity.
Light and gravity: a journey of discovery.
Newton's Mass Theory.
Let's start more than 300 years ago. At that time, Isaac Newton had a bold idea: if light was made of particles, would those particles pass through gravitational waves like other weighty matter? Newton's idea, although it could not be confirmed by experiments at the time, inspired later generations of scientists.
Eddington observational test.
By the early twentieth century, scientists had begun to solve this problem with more precise experiments. In 1919, scientist Arthur Eddington observed through a lunar eclipse whether stars would deviate from their orbits as they approached the Sun. This discovery not only confirmed that light is distorted under gravitational influence, but also proved Einstein's theory of general relativity.
The triumph of the Great Theory of Relativity.
Based on his theory of general relativity, Albert Einstein gave a broader theory of how gravity affects space and time, and how light travels through space and time. His theory that light is distorted by gravity is very different from what Eddington observed.
Gravity lens: a new kind of light field of view.
With the advent of general relativity, people have a new understanding of the universe, and in the process, people have paid more attention to the role of gravitational lensing. Since the light passes through a strong gravitational field, it is as if it passes through a mirror, so we can see "magnified" distant objects. This discovery not only verifies the general theory of relativity, but also provides a powerful means for astronomers to explore the universe to find dark matter and study the Milky Way.
New means of detection.
Thanks to the development of technology, scientists can make more accurate observations. Using advanced instruments like radio telescopes, researchers can prove Einstein's theory right by measuring the smallest deviations that occur when light passes through the sun and other objects.
Conclusion. In short, the study of the connection between gravity and light is not only a major physical exploration, but also a sign of endless exploration of the world. From Newton and Einstein to contemporary astronomers, this process shows that the foundation of science is being established step by step, step by step.