Who was the first to successfully measure the speed of light?
The fact that light travels faster than sound is clear, but how much faster? Is the speed of light even infinite? 1638 Galileo Galilei dared to challenge this prevailing view. By placing two people each with a lantern at a long distance from each other and measure the time it took for them to understand each other’s lights, he tried to measure the speed of light. Galilei concluded that the speed of light is either infinite or at least very high.
The first to show that the speed of light is finite was the Danish astronomer Ole Rømer, who in the 1670s, during a period of ten years worked at the Observatory in Paris. In September 1676 he announced that his discovery in the French Academy of Sciences. Rømer had studied one of Jupiter’s moons, Io, and realized that the timing of Io’s disappearance and reappearance at lunar eclipses varied depending on Jupiter’s current distance from Earth. The explanation proved that the motion of light is not instantaneous but other vice, that the speed of light is finite.
After that Englishman James Bradley with the help of stellar aberration in 1729, calculated the value for the speed of light is 303,000 km / s.
The first non-astronomical way to measure the speed of light on demonstrated by the French physicist Hippolyte Fizeau in 1849. Fizeau used a beam of light, a rapidly rotating gears and a mirror placed in a friend’s house eight and a half kilometers away, and came thus to a light speed of about 312 000 km / s.
In 1983 it was documented the speed of light in vacuum is equals to 299 792.458 km / s by the International Union for weights and measures. Why is there a physical speed limit in light’s propagation?
During his research Albert Einstein’ said speed of light is constant. It is equals to 299 792 458 m / s. or roughly 300,000 Km/s. That is way too fast. That is the speed limit of the universe. Sometimes we could call this as the speed of causality.
Only massless things can be archive this speed limit. For an example photons can go up that speed since photon has no mass. That has zero rest energy.
The speed of light/ or speed of causality would be the way that our universe form. That is one of the fundamental property that is in the very base foundation when the universe forms. It is an unmovable fact. It is not a result of physical cause or phenomena.
Perhaps scantiest argue that there could be some other millions of billions of universes out there which spin off by the big bang that could holds different values for these constants. It could slightly or radically different values from ours.