Data di registrazione: Oct 2010
Re: A volte ritornano - Perplessità sulla teoria del Big Bang, 2
E dopo le perplessità sulla singolarità iniziale...
... quelle sul periodo inflattivo.
Problema 1: probabilità bassa considerati i parametri in questione.
"Inflation was supposed to create a huge volume of space matching the observed large-scale features of our universe naturally. But unless the inflaton energy curve had a very specific shape (obtained by finely tuning one or more parameters, abbreviated λ here), the outcome would be “bad”—a huge volume with too high a density and the wrong distribution of galaxies. Given the range of possible λ
values, bad inflation seems more likely".
Problema 2: probabilità bassa di condizioni preesistenti compatibili.
"Inflation was supposed to occur no matter what the initial conditions of the universe were. Further analysis suggests otherwise. Of all the ways the universe could have begun, only a tiny fraction would lead to the uniform, flat state observed today. An overwhelming fraction of these would reach this state without significant inflation; only an infinitesimal fraction would do so by going through a long period of inflation."
Problema 3: genererebbe conseguenze infinite.
"Inflation is known for making precise predictions that have been confirmed by observations. But does it really? Once inflation starts, quantum jittering keeps it going in the bulk of space. Where it does end, a bubble nucleates and grows. We live in such a bubble, but it is atypical; most are younger. In fact, an infinite number of bubbles form with an infinite variety of properties. Everything that can happen does happen in some bubble. A theory that predicts everything predicts nothing."
Problema 4: bisogna concepire condizioni ad hoc.
"A recurrent criticism of inflation is that the invoked inflation field does not correspond to any known physical field, and that its potential energy curve seems to be an ad hoc contrivance to accommodate almost any data obtainable."