Are the rays of light in the sky curved?
In 1919, the Times in London published an article that shocked everyone. Its title is “Curved SkyLight.” At first glance, that way of saying is confusing. That conclusion is a natural consequence of the curved space made by Einstein. What is space curvature? Moreover, what power did create a curved space?
From daily life experiences, we know that when an object is subjected to a direction of external force that is not the same as its speed of motion, the object will deviate from its original path and move along a curved path. A prime example is the horizontal throw motion. After a stone is thrown in a horizontal direction, it is subjected to vertical gravity downward, so its path turns into a paragon.
Everyone knows that the Earth revolves around the Sun while the Moon revolves around the Earth, their operating orbits are also curved. Its cause is that there is a universal gravitational force between the Sun and the Earth as well as between the Earth and the Moon. Comparing gravitational force with friction, an elastic force that we are very familiar with and we can see that gravitational force between two objects is generated through spatial distance apart. The ghost force elastic force is generated by two objects directly in contact with each other. The space in which this gravity occurs is called the gravitational field.
Einstein’s theory of relativity’s main content is the notion that time and space are not absolute, as Newton said, but that physical quantities are closely related to the state of motion can. Based on the principle of relativity, the Earth moves in a curved orbit and must be considered the gravitational field generated by the Sun that causes the space to bend. The greater the mass of an object is, the more pronounced the curved space produced. When another body of a certain mass and speed. From very far away moving too close to the mass object, goes from “flat” space into “curved” space, it is also changed to curved immediately.
Using that point of view to analyze the phenomenon of light propagation, we see that light travels in a straight line, that is because light does not enter curved space, or even though space exists. The mass causes the “curvature”, the degree of curvature is too small. We do not observe the difference between the light path and the straight line. However, once light enters a “curved” space formed by large masses, the light no longer travels in a straight line but must follow a curve. This idea is not baseless imagination but it is completely supported by experimental observations.
As early as in May 1919, the British astronomer, AS Eddington, took advantage of the opportunity to observe a total eclipse once, leading an expedition to Africa to experience the phenomenon of light bent due to the mass the Sun causes. Although this observation is too difficult, the error is also large. Still, the determined measurement results repeatedly show that the light rays are indeed bent, the curvature angle is in the range of 1.61 “- 1.95”. In November of that year, the Royal Academy of Sciences and the Royal Astronomical Society of Great Britain broke the rule of conducting a large-scale joint meeting, announcing to everyone in the world one of these greatest achievements in the history of human science.