The bending of light is a bit of a mis-representation of what is really the bending of space-time through which the light travels - that spacetime is bent by mass of objects. The astronauts aboard the International Space Station, for example, experience complete weightlessness, even though the Earth is accelerating them towards its center with about 90% of the force we experience here on its surface. In 1919, however, a very long eclipse was slated to pass over South America and Africa, and Sir Arthur Eddington of Great Britain was prepared. Does it simply continue in a straight line, undeflected from its original path? As long as falling objects accelerate due to gravity, we have every reason to believe that gravity bends light, too. Each observer will not only see time passing at the same rate for themselves of one second per second, but they will be unable to learn anything about the outside world from within their own limited frame-of-reference. Albert Einstein-Bending of Light. In this article, I will describe one of the classical tests of general relativity, arguably the most famous one, which is the bending of light by the Sun (or any spherically symmetric, time-independent gravitational field) as shown in Fig. Light bending by gravity is caused by the property of photon not the curvature of spacetime. The cause of the acceleration, whether from inertial (thrust) or gravitational effects, cannot be discerned from this observation alone. EY & Citi On The Importance Of Resilience And Innovation, Impact 50: Investors Seeking Profit — And Pushing For Change, Michigan Economic Development Corporation With Forbes Insights, occurred over the continental United States, but clouds intervened, Treknology: The Science of Star Trek from Tricorders to Warp Drive, Beyond the Galaxy: How humanity looked beyond our Milky Way and discovered the entire Universe. Einstein first proposed his General Theory of Relativity in 1915. This can be seen mathematically by rewriting the geodesic equation followed by the particle as (see Schutz): Now, photons travel on null geodesics, which implies that the parameter λ must be some affine parameter different from the proper time τ. The following image shows the deflection of light rays that pass close to … In physics, redshift is a phenomenon where electromagnetic radiation (such as light) from an object undergoes an increase in wavelength. Before... [+] any quantitative predictions were made, even before Einstein had worked the theory out, he knew that light must be bent by masses. And if so, what is the magnitude of the force it experiences? Einstein recalled how, at the age of 16, he imagined chasing after a beam of light and that the thought experiment had played a memorable role in his development of special relativity. It's the changes in motion — the acceleration — that cause what you experience as a force, just like what you'd expect from Newton's most famous equation: F = ma. Newtonian physics also predicted light would bend due to gravity, but only by half as much as Einstein's theory predicted. In particular: That last case, however, would describe an accelerating elevator and a stationary elevator in a gravitational field equally well. Therefore, Einstein reasoned, it would not only be possible to predict that light rays cannot travel along a straight path when they're in a gravitational field, but the magnitude of deflection could be calculated simply by knowing what the strength of the gravitational effects in the vicinity of that mass were. The results of those observations was compelling and profound: Einstein’s theory was right, while Newton’s broke down in the face of the bending of starlight by the Sun. 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