Aside from not seeing any obvious long-term changes in the universe, I can believe that this notion was unsupported. However, I'm suggesting that it wasn't just unsupported, it was contradicted by contemporary physical knowledge like the second law. Either these two ideas can be reconciled, and I'd like to know how, or they somehow held this belief despite the contradiction, in which case I'd still like to know how...Chronos said:
Chronos said:
Jocko Homo said:
This is a wrong understanding. Einstein originally believed that our universe was static and eternal, and tried to adjust General Relativity to fit that belief. That attempt ultimately failed, as there is no stable static universe in General Relativity.TrickyDicky said:
The difference is pretty tremendous. They had statistical mechanics at that time (it was formulated first by Boltzmann in 1870), so they knew, or at least should have known, that the second law was more fundamental than the first.TrickyDicky said:
Chalnoth said:
You said that GR proposed a static universe. This is false. You can't make an eternal static universe in General Relativity. Einstein made a static universe in General Relativity, but it was proven to be unstable, and that instability makes a static, eternal universe impossible.TrickyDicky said:
I said Einstein proposed a cosmological model in 1916 based in GR. Are you seriously arguing this is not so?Chalnoth said:
I'm saying that this cosmological model (a proposed static, eternal universe) was unstable, and thus could not ever have been eternal. That is, the model was not consistent.TrickyDicky said:
The fact that it is unstable contradicts the idea of it being eternal, which was part of the proposal. It was not a valid model.TrickyDicky said:
Well, that's a different beast. That model was also wrong anyway.TrickyDicky said:
The natural way to reconcile the two ideas is through http://en.wikipedia.org/wiki/Poincar%C3%A9_recurrence_theorem" . Every possible configuration will recur eternally. Such a universe would spend most of its time in a maximum entropy state, because most of its states would have this property, but eventually there would be a fluctuation that would drive it into a lower-entropy state.Jocko Homo said:
I should mention that this view, in its simplest incarnation, utterly fails to explain our universe, because smaller decreases in entropy are exponentially-favored. This means that given this situation, it is more likely for the current universe, as it exists today, to fluctuate out of the equilibrium system than for an early universe to do the same (the early universe had much lower entropy). It is still more likely for this to happen for a single galaxy instead of the whole universe. It is still more likely for this to happen for a single solar system. It is still more likely for a disembodied brain to pop into existence, think a single thought, and disappear than it is for even our own solar system to come into existence all on its own.mitchell porter said:
Jocko Homo said:
I doubt many believed in an interventionist god. That sort of god belief has been rare among scientists for quite some time.mrspeedybob said:
For historical correctness, see "The history of the cosmological constant problem" http://arxiv.org/abs/gr-qc/0208027TrickyDicky said:
The Second Law of Thermodynamics states that the entropy, or disorder, of a closed system will always increase over time. This means that the universe as a whole is constantly moving towards a state of maximum disorder. A static and eternal universe, on the other hand, would have a constant and unchanging state, which goes against the idea of increasing entropy. Therefore, the Second Law of Thermodynamics poses a challenge to the concept of a static and eternal universe.
A cyclical universe is one in which the universe expands and contracts in a never-ending cycle. The Second Law of Thermodynamics presents a problem for this idea because each cycle would result in a decrease in usable energy and an increase in disorder. This would eventually lead to a state of maximum entropy, making it impossible for the cycle to continue. Therefore, the Second Law of Thermodynamics challenges the idea of a cyclical universe.
Currently, there is no scientific evidence to support the concept of a static and eternal universe. In fact, the majority of evidence and observations point towards an expanding and evolving universe, rather than a static one. The Second Law of Thermodynamics also poses a challenge to this concept, as it suggests that the universe is not in a state of equilibrium, but rather constantly changing and moving towards disorder.
Some scientists have proposed alternative theories, such as the "steady state" theory, to reconcile the Second Law of Thermodynamics with a static and eternal universe. However, these theories have not been widely accepted and do not have strong supporting evidence. Others argue that the concept of a static and eternal universe may simply be a philosophical idea rather than a scientific one, and therefore does not need to be reconciled with the Second Law of Thermodynamics.
The Second Law of Thermodynamics can be applied to the universe as a whole, as it is considered a closed system. However, there are some complexities and debates surrounding this application. Some argue that the universe may not be a perfectly closed system, as it is constantly expanding and may be influenced by external factors. Others suggest that the Second Law of Thermodynamics may only apply to isolated systems, and the universe as a whole can still maintain a state of equilibrium. This is still a topic of ongoing research and debate in the scientific community.