| effect due to general theory of relativity, describing the fact that a periodical process has a larger period when it occurs in a stronger gravitational field than when it occurs in a weaker gravitational field, and vice-versa
EXAMPLE A typical example of the gravitational shift is a photon emitted from a star (a domain with stronger gravitation) to an observer at the Earth's surface (where there is weaker gravitation). The synonym "gravitational red shift" is often used in this case.
Another example is that of a caesium clock at a GPS satellite at the height of 20 200 km above the Earth's surface (weaker gravitation) which shows a higher frequency (10,230 000 000 00 MHz) than that at the Earth's surface (stronger gravitation, frequency set to 10,229 999 995 43 MHz). This setting covers both gravitational shift and time dilatation, the last effect being five times smaller and oriented in the opposite direction to gravitational shift.
Note 1 to entry: Gravitational shift assumes that all rotational and speed effects are disregarded.
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