Spacetim1 - after travelling more than 100 kilometers!...

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Spacetime Two consequences of Special Relativity are a stationary observer will find (1) the length of a fast-moving object is less than if the object was at rest, and (2) the passage of time on the fast- moving object is slower than if the object was at rest. However, an observer inside the fast- moving object sees everything inside as their normal length and time passes normally, but all of the lengths in the world outside are shrunk and the outside world's clocks are running slow. One example of the slowing of time at high speeds that is observed all of the time is what happens when cosmic rays (extremely high-energy particles, mostly protons) strike the Earth's atmosphere. A shower of very fast-moving muon particles are created very high up in the atmosphere. Muons have very short lifetimes---only a couple of millionths of a second. Their short lifetime should allow them to travel at most 600 meters. However they reach the surface
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Unformatted text preview: after travelling more than 100 kilometers! Because they are moving close to the speed of light, the muons' internal clocks are running much slower than stationary muons. But in their own reference frame, the fast-moving muons's clocks run forward ``normally'' and the muons live only a couple of millionths of a second. Time and space are relative to the motion of an observer and they are not independent of each other. Time and space are connected to make four-dimensional spacetime (three dimensions for space and one dimension for time). This is not that strange---we often define distances by the time it takes light to travel between two points. For example, one light year is the distance light will travel in a year. To talk about an event, you will usually tell where (in space) and when (in time) it happened. The event happened in spacetime....
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