II 5 Why Twins?It should not be so surprising for one twin to be older than the other. Even without relativistic effects, if one twin went on a long trip and was put in cryogenic hibernation as in 2001: A Space Odyssey, then he would return noticeably younger just like the twin paradox.
As mentioned above, although the idea of twins was given by Weyl 1922, it is only around the fifties of the preceding century that the name twin paradox was very often used. To find the hidden reason for this habit, I propose to investigate the collective image of twinship as it was elaborated trough myths and religions and to relate it to the use of the word.
I begin by quoting B.Beit_Hallahmi and M.Paluszny (1974) from their paper on twinship:
"…there are common psychological elements in both mythological and scientific approaches to twinship. The major elements are fascination and ambivalence. Fascination with twin births has always been combined with a great deal of apprehension and ambivalence. In both primitive and modern societies, multiple births have been viewed as a potential source of familial and social conflict and complication."
Effectively one finds in the Bible and several mythologies frequent situations of conflict between twins. In the Bible one can mention Cain and Abel with the murder of Abel and also Jacob and Esau. Esau wants to kill his twin brother Jacob but Jacob has time to escape.
In the Greek mythology (See the works of Aeschylus (1966)), the fight between Atreus
(preferred by Zeus) and Thyestes (preferred by the people) with all the successive conflicts in the Atrides family is well known. In the roman mythology, the two twins Remus and Romulus (see the details of the story in Plutarch) who are the founders of Rome, are fighting for the government of the city. It results that Romulus kills his twin Remus.
In a complete different context, Levi-Strauss (1995) analyzed the myths of some North
America and South America Indians and considers the antagonism between twins as a
source of disequilibrium. In fact, the twins' conflict is not completely general since there are also some cases where the twins manage their life in peace. For example in the Greek mythology the twins Castor and Pollux are in good relationship and there are taken as example of a peaceful twinship. Nevertheless the collective image of twins is frequently related to conflict and violence. This double presence of two identical persons is seen as something scandalous and abnormal. One of them must disappear or at least put in a bad position.
I propose to adopt this point of view considering the twins of the paradox. In the unconscious mind, the twinship must be destroyed and in the paradox this is what happened: one of the twins remains young and the other old, when young is better than old. I propose to interpret the habit to give the name "twin paradox" to the clock paradox as an intrusion of the subconscious in the language of physicists. All the efforts of the physicists are to show the asymmetry in the twins as it must be.
Wednesday, December 19, 2012
History of twin paradox
This new paper on the history of the relativity twin paradox has this amusing argument for the psychological significance of using twins to illustrate time dilation: