Do you know how GPS and the theory of relativity are related?

The Global Positioning System (GPS) It's such a common app that we can already carry it on our smart device. And, believe it or not, It is related to the theory of relativity. If you want to know how, keep reading.

November 25, 1915 presented Albert Einstein a revolutionary mathematical formula that would change the way things are measured.

Initially, it was thought that space and time were rigid and did not change from one place to another. In other words, a kilometer is a kilometer and a second is a second here and everywhere else in the universe. But the theory of relativity would change that.

It all began with a problem the scientist posed when he was 16 years old. His question was what a beam of light would look like if someone were traveling alongside it at the same speed. Using his imagination, he took two postulates: Galileo Galilei's theory of relativity from 1632, and James Clerk Maxwell's equations of electromagnetism.

Assuming both are true. Einstein believed that if time is relative, then space and distance must also be relative. He reflected all of this in his study Electrodynamics of Moving Bodies.

Einstein's theory indicates that space and time are not rigid entities., but rather both are related, forming a third entity, which can be called spacetime. This new entity could be deformed by speed and gravity, causing it to speed and severity are relative.

Over time, this theory has been tested countless times And it's very important in various applications we frequently use, such as the one we're discussing in this post. Many of them use GPS to track our routes or to suggest them.

How does GPS relate to theory?

GPS receives information from satellites orbiting the Earth, supplying its position and current time on a regular basis.. There are at least 24 satellites distributed across 6 orbital planes, with 4 satellites in each plane at an altitude of approximately 20,000 kilometers. This ensures that at least 4 of them are always visible from any point on the planet at any time.

In this way, the GPS On Earth, it calculates its distance using signals from three satellites, measuring the time difference between the departure and arrival times of the signals. With these three signals, it locates itself in space using a process called trilateration (triangulation plus distance).

Satellites have an atomic clock that tells the time accurately.. But time on Earth passes more slowly, as it is influenced by our planet's gravity. Unlike time at the satellite's location, which passes more quickly because the gravitational pull is weaker or almost nonexistent in space.

For this reason, calculating the distance between the signal's departure and arrival times must take this effect into account. This is where the theory of relativity comes in. If it is not considered, all GPS readings would shift by about 10 kilometers per day.

Thanks to Einstein, humanity can know its location in nanoseconds. Did you know about this connection between the theory of relativity and GPS? Do you know of any other related devices or applications? Leave your comments below, dear readers.

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