Talk:Perfect Cosmological Principle

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Astronomy: Cosmology

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contradictory principle needs controversial opinion

I think this principle (as much as its less perfect version) is totally contradictory to commons sense. Therefore I am missing the big lot of criticism towards such ideas! Sorry for not being able to provide that kind of information myself.
--86.131.238.201 18:07, 6 September 2007 (UTC) ...tb[reply]

In a sense, you're obviously right because the perfect cosmological principle is wrong. But it is based on the sound logical basis that, unless we have evidence to the contrary, we should assume that our place and time in the universe are not “special” but are representative of the universe at all places and times. But both this and the regular cosmological principle are axioms of convenience that are only good as long as they are not disproved by observations. For example, in one sense we are in a “special” place - we live on the surface of a planet, while most of the universe is not the surface of a planet - but we understand why that is. This is better discussed on the main cosmological principle page and so I'm suggesting that the two be merged. -- Cosmo0 21:30, 22 September 2007 (UTC)[reply]

Definitely should not be merged -- they are different principles. And BTW the perfect cosmological principle is not wrong -- it is adhered to by chaotic inflationary theory. --Michael C. Price ^talk 07:49, 23 September 2007 (UTC)[reply]

Why is it wrong?

As a layman, I ask myself whether, according to a unified theory of everything (if such a beast can be created), is this perfect principle not true? Of course the World is neither homogeneous (the mass distribution is very inhomogeneous, compare Earth to interstellar space) nor isotropic (try dropping an apple - it knows where to go!). What is (according to common thinking) homogeneous and isotropic are the regularities, the basic laws. These laws may have changed over time, but if thay can be formulated in a form where they haven't, couldn't we say that the world is homogenous and isotropic in time as well as in space?--Noe (talk) 14:58, 16 June 2008 (UTC)[reply]

Whether the Perfect cosmological principle is wrong is not decided yet by science. It is wrong in the Big Bang model since it requires that the universe is expanding, but it might not since energy may be conserved on universal scale. Then the idea of expansion has to be abandoned since such universe can't be expanding (nor contracting) and what is observed is necessarily to be an illusion. As is also predicted by the flatness of spacetime and simple Newtonian calculations that are not allowed to be published since some cosmologists push the Big Bang hypothesis. Neither mentioning those calculations that would falsify the Big Bang hypothsis is not allowed. But they should be done to show that there is no Hubble redshift already in static universe before jumping to conclusion that our universe is expanding. Why they are not allowed to be published? Is there any creationist lobby acting in science? Jim (talk) 06:39, 4 May 2011 (UTC)[reply]

The steady state model includes the same form of expansion as the Big Bang model but also postulates that new matter is being continuously created so that the mean density remains the same at all times. The principle is certainly wrong, the observation of the CMBR shows that the universe was in a very different state when that light was emitted. George Dishman (talk) 19:07, 11 January 2013 (UTC)[reply]

Chronology

Wasn't the principle a hypothesis by Hoyle as the basis for his Steady State cosmology? Surely that preceded chaotic inflation by a long way, I think this article needs checking by someone who knows the history of the hypothesis. George Dishman (talk) 19:02, 11 January 2013 (UTC)[reply]