But in addition to pushing the field of cosmology forward, the findings are a good real-world example of Einstein’s special relativity theory—and they demonstrate how researchers are still putting the ...

Special relativity indicates that it is possible for two observers in different reference frames to observe events happening at different times, if they are traveling at close-to-light speeds.

For example, a spacecraft traveling at 90% the speed of light would appear about 2.3 times shorter to an external observer. Length contraction is not an optical illusion but a real consequence of the ...

The Reichenbach-Grunbaum thesis of the conventionality of simultaneity is clarified and defended by developing the consequences of the Special Theory when assumptions are not made concerning the ...

This week's 100th anniversary of Albert Einstein's general theory of relativity is a geeky cause for celebration, but the concept also faces a tough test.

One of the most famous concepts in science was introduced in a paper with the uninspiring title, "On the Electrodynamics of Moving Bodies." A little ...

Well connected: an optical clock at PTB was used in the comparison. (Courtesy: PTB) Atomic clocks in France, Germany and the UK have been used to perform the best-ever confirmation of time dilation as ...

Special relativity has changed the way we think about time and the order of events. Einstein famously showed that two events can look simultaneous to one observer but not to another. In fact, it ...

Einstein's theory of special relativity beautifully marries the realms of space and time. But more importantly for Designolle's team, it also leads to constraints on how fast information travels.

The tachyon, a hypothetical, faster-than-light particle previously thought unworkable with relativity, may have some tricks up its sleeve.