I recently came across this over four year article that I linked to below.
I always here that there is so much evidence for the Big Bang, that it most likely won’t be dismissed any time soon.
The article says that the universe may actually be trillions of years old and has lots of other differences between the current Big Bang model.
Do mainstream scientists agree that this newer theory may be correct and that the current Big Bang theory may be wrong on many levels? Or is this theory not really that new at all and doesn’t really reject long held ideas of the Big Bang?
Ah, the cyclical model of colliding M-branes. It’s been banging around since 2001.
It’s an interesting hypothesis. Similar oscillating universe models have been proposed in the past, then discarded when they were inconsistent with known physics.
This model has not been reconciled with known physics yet either, as far as I can tell.
The explanatory power of a theory is scientifically irrlevant.
The most characteristic element in this situation seemed to me the incessant stream of confirmations, of observations which “verified” the theories in question; and this point was constantly emphasize by their adherents. A Marxist could not open a newspaper without finding on every page confirming evidence for his interpretation of history; not only in the news, but also in its presentation — which revealed the class bias of the paper — and especially of course what the paper did not say. The Freudian analysts emphasized that their theories were constantly verified by their “clinical observations.” As for Adler, I was much impressed by a personal experience. Once, in 1919, I reported to him a case which to me did not seem particularly Adlerian, but which he found no difficulty in analyzing in terms of his theory of inferiority feelings, Although he had not even seen the child. Slightly shocked, I asked him how he could be so sure. “Because of my thousandfold experience,” he replied; whereupon I could not help saying: “And with this new case, I suppose, your experience has become thousand-and-one-fold.”
No. At best it is a controversial and not well-accepted theory as of yet.
As Qadgop indicates, cyclical universe theories are not all that new. In any case, it does not necessarily discard the occurence of a Big Bang as the origin of the present universe, it just postulates there have been previous cycles of Big Bangs and Big Crunches before.
It may help to distinguish between the “Big Bang” as the beginning of the universe and the more technical usage of the Hot Big Bang.
The latter is used by cosmologists to refer to the universe having passed through a relatively brief period of immensely high densities and temperatures about 13.7 billion years ago. There is now a considerable amount of precision evidence from the likes of WMAP and primordial nucleosynthesis (a pdf) that this happened. There’s essentially no disagreement amongst astronomers that such a period occured or about the time in the past that it did. Steinhardt and Turok completely accept both that there was a Hot Big Bang and the timescale.
Where there’s uncertainty is in what happened before the Hot Big Bang period. In the more conventional view, (much) less than a second before that period started time and space themselves came into existence. The universe has a beginning, followed more or less immediately by a Hot Big Bang.
In Steinhardt and Turok’s version, there is a trillion (or whatever) year series of events that triggers a Hot Big Bang phase 13.7 billion years ago.
From then on the two views are equivalent. There’s no basis to suppose that Steinhardt and Turok’s suggestion undermines the standard account of the subsequent Hot Big Bang and the following 13.7 billion years.
And, of course, the big problem with models like this is that they’re very difficult or impossible to test. Sure, maybe there’s another brane banging around out there, but until we figure out how to launch rockets at right angles to reality, how are we going to detect it?
This statement is a little misleading. I believe what you are saying (and certainly the point that Popper was making) is that a “theory” created post hoc to rationalize the proceeding events or observations is not, properly speaking, a scientific theory at all; it is, at best, a supported hypothesis that remains to be tested. A genuine theory must be falsifiable, i.e. you must be able to conjure up a test that is unique to your explanation and then test your observations or actions against it with the earnest effort to disprove it. Only after multiple, independent efforts at disprove have been made and failed can we accept an idea as being a valid theory. And in the real world, absolute disproof is impossible; ultimately, you could challenge that observation itself is unreliable, and that there be a man behind the curtain running the whole show in such a way that you can’t tell the difference.
Regarding brane theory, there is really no way to even provisionally disprove it, and in fact it may not be inconsistent with a Big Bang-type theory (if the latter can be considered a kind of subset of the former). It’s an interesting thought experiment, and if we can validate it someday it may give us some clue as to what is going on beyond the cosmic event horizon in a very general sense, but I’d guess that the odds of us figuring out what’s really going on at a fundamental, hyper-universal level are slim to none.