Newsgroup: it.scienza.fisica
Titolo: Effetto "Ratsche"

Premetto che non sono un fisico, bensì un chimico. Leggendo uno degli scorsi 
numeri dello Spiegel, nel contesto di un lungo articolo in cui si parla, in 
senso lato, di biologia dei primati, e di un particolarissimo effetto che si 
verifica nel loro genoma, a un certo punto si dice (traduco dal tedesco). 
«Nessuno può dire se tali trasformazioni (Umwandlungen) molecolari 
relativamente piccole si siano manifestate in qualcosa di così importante 
come il "Ratschen-Effekt"».
La mia domanda è cosa sia l'effetto "Ratsche" e quale sia la traduzione 
italiana del termine. La traduzione letterale die "Die Ratsche" è 
"l'arpionismo", ma non vedo il nesso.
Mi pare invece di intuire che possa trattarsi di un speciale effetto di tipo 
quantistico, come teletrasporto o qualcosa del genere.
C'è qualche cortese e volonteroso fisico che mi possa aiutare ?
Grazie anticipate a chi mi vorrà rispondere e saluti a tutti
Mimmo - Milano

 "l'arpionismo", ma non vedo il nesso.
Suppongo che possa essere il "ratchet effect" in inglese:
http://en.wikipedia.org/wiki/Ratchet_effect
The ratchet effect the commonly observed phenomenon that some processes
cannot go backwards once certain things have happened, by analogy with
the mechanical ratchet that holds the spring tight as a clock is wound
up.
Garrett Hardin, a biologist and environmentalist who also wrote of the
'tragedy of the commons', used the phrase to describe how food aid keeps
alive people who would otherwise die in a famine. They live and multiply
in better times, making another bigger crisis inevitable, since the
supply of food has not been increased.
Austrian school economist Robert Higgs has also used the term to
describe the seemingly irreversible expansion of government in times of
crisis in his book Crisis and Leviathan.
The ratchet effect is also used as a term for the results of an economic
strategy arising in an environment where incentive depends on both
current and past production, such as in a competitive industry employing
piece rates. The producers observe that since incentive is readjusted
based on their production, any increase in production confers only a
temporary increase in incentive while requiring a permanent greater
expenditure of work, and thus decide not to reveal hidden production
capacity unless forced to do so.
The ratchet effect is referred to in many disciplines, from politics to
management to evolutionary theory. One of the manifestations of the
ratchet effect in mathematics is Parrondo's paradox.
In terms of politics, the "ratchet effect" was used to describe the
government's inability to scale back the huge bureaucratic organizations
that were once needed. Oftentimes, these machines were created in times
of war to fuel the needs of their troops abroad. The "ratchet effect"
can also be viewed through the lens of international organizations that
have trouble with reforms due to the myriad layers of bureaucracy that
were previously created.
Ciao
-- 
Riccardo Campana
pabel...@gmail.com
"Physics is like sex: sure, it may give some practical
results, but that's not why we do it"  (Richard Feynman)

> La mia domanda è cosa sia l'effetto "Ratsche" ...
[snip]