# clock paradox

- Also known as the twins paradox or two-clock paradox. An apparent paradox of special and general relativity theory . The time dilation effect in the special theory of relativity is that clocks at rest in different inertial frames observe each other to run slow. The alleged consequence is that if we consider a universe of two adjacent clocks at rest with respect to each other, which are then separated and subsequently reunited, after this event each will be slow relative to the other (i.e. each will show less time to have elapsed than the other), which is a contradiction. The argument is that in a universe with no independent objects providing a frame of reference, there is no fact of the matter which clock should be considered to be the one that has moved. The flaw in the reasoning is that if a clock goes on a journey then there is no inertial frame in which it is at rest throughout the interval: it needs to accelerate outwards and accelerate back. Whichever clock does this will indeed show that less time has elapsed when reunited with another clock with no past history of acceleration, for this is a physical effect consequent upon accelerating with respect to space. However, the clock paradox does show that this real acceleration does not supervene upon the symmetrical properties of the two clocks, in the universe of which they are the only constituent masses.Asymmetric ageing as a consequence of changes in velocity is a well-confirmed empirical consequence of general relativity theory. In general relativity theory, space involves a dynamic field created by gravitational mass, and movement relative to it is a physical state with its own consequences.

*Philosophy dictionary.
Academic.
2011.*

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**clock paradox**— laiko paradoksas statusas T sritis fizika atitikmenys: angl. clock paradox; twin paradox vok. Uhrenparadoxon, n; Zwillingsparadoxon, n rus. парадокс близнецов, m; парадокс времени, m; парадокс часов, m pranc. paradoxe de l’horloge, m; paradoxe… … Fizikos terminų žodynas**clock paradox**— noun The phenomenon in which two observers who start together with identical clocks, follow different timelines, and then rejoin can have different elapsed times on their clocks, especially if one travels at a relativistic speed. Syn: twin… … Wiktionary**two-clock paradox**— See clock paradox … Philosophy dictionary**Twin paradox**— In physics, the twin paradox is a thought experiment in special relativity, in which a twin makes a journey into space in a high speed rocket and returns home to find he has aged less than his identical twin who stayed on Earth. This result… … Wikipedia**twin paradox**— laiko paradoksas statusas T sritis fizika atitikmenys: angl. clock paradox; twin paradox vok. Uhrenparadoxon, n; Zwillingsparadoxon, n rus. парадокс близнецов, m; парадокс времени, m; парадокс часов, m pranc. paradoxe de l’horloge, m; paradoxe… … Fizikos terminų žodynas**twin paradox**— noun The clock paradox … Wiktionary**twins paradox**— See clock paradox … Philosophy dictionary**Carroll's paradox**— In physics, Carroll s paradox arises when considering the motion of a falling rigid rod that is specially constrained. Considered one way, the angular momentum stays constant; considered in a different way, it changes. It is named after Michael M … Wikipedia**Bell's spaceship paradox**— is a thought experiment in special relativity involving accelerated spaceships and strings. The results of this thought experiment are for many people paradoxical. While J. S. Bell s 1976 version cite book | author=Bell, J. S. | title=Speakable… … Wikipedia**Three O’Clock (film)**— Infobox Film name = Three O Clock caption = Three O Clock Poster director = Glen Chua producer = Glen Chua Tyler Reids writer = Glen Chua starring = Glen Chua Alexandra Caldwell George Amoako distributor = Moonlite Productions (CAN) released =… … Wikipedia