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Quantum Equation Suggests Universe Had No Beginning
cyberspittle writes: The universe may have existed forever, according to a new model that applies quantum correction terms to complement Einstein's theory of general relativity. The model may also account for dark matter and dark energy, resolving multiple problems at once. "In addition to not predicting a Big Bang singularity, the new model does not predict a "big crunch" singularity, either. In general relativity, one possible fate of the universe is that it starts to shrink until it collapses in on itself in a big crunch and becomes an infinitely dense point once again. ... In cosmological terms, the scientists explain that the quantum corrections can be thought of as a cosmological constant term (without the need for dark energy) and a radiation term. These terms keep the universe at a finite size, and therefore give it an infinite age. The terms also make predictions that agree closely with current observations of the cosmological constant and density of the universe."
It's interesting, but I'm curious as to whether the model shows a universe developing with the features we observe. The density of the universe is one thing, the general structure of it is another. There seems to have been a lot of thinking around how the universe was shaped by the big bang including all sorts of models and simulations. It'll be interesting to understand if this new model also fits.
And as far as a universe with no beginning or end is concerned, what's the problem?
In a word: entropy.
"If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
The question is meaningless, concept of big bang does not include a "before". Mind you, nobody can actually see beyond cosmic background radiation, big bang is just the best performing model we have, various quantum gravity approaches might do away with singularities altogether drastically altering concepts like black holes and big bang. But we don't have any quantum gravity theories, none that are really fully formulated and functional at least, best we have is general relativity. And GR results in singularities like big bang and black holes. It might be how the universe actually is or it might be a fault in GR, but until we have an alternate theory that we can test and compare, GR is the best we have.
You know, what I've often asked myself is, "What was there before the Big Bang?"
Thats a bit like asking what is south of the south pole.
Obvious question, if the universe is infinitely old why do we still have hydrogen left for fusion?
In a word: entropy.
Good call! Don't see red shift explained either.
In this model, the universe is still expanding, it's not static at all. So redshift is just explained the normal way, in fact the Hubble constant is mentioned in the actual paper.
The paper is far above my level of understanding but, as far as I understood, when you play time backward but take quantum trajectories (whatever those are) into account, the universe doesn't come together in a single point but in some other state, much more dense than today but not a singularity. So the universe is still expanding from a very dense earlier state, but there's no longer an actual singularity in the beginning. At a point in the past where people used to naïvely think the density had to become infinite, quantum trajectories actually keep it from reaching a singularity.
Thats a bit like asking what is south of the south pole.
Maybe. But the current model could be wrong.
I suppose that radioactive materials were put here by Satan to trick us. After all, with a perpetual universe we would have reached the half life of nuclear materials over and over again and we would have no radioactive materials at all. Oops!
Certainly I agree with you, there is a lot we don't know. The trouble is, at the moment, in order to speculate on this, we are leaving science and entering philosophy. Science does not have an answer for us here, and maybe never will. We have some math, but nothing that really means anything to us.
I would say that these questions cannot be objectively answered - there is no way to measure what happened 'before' since there is no frame of reference that would be meaningful to us and allow us to understand what 'happens' outside our little bubble of physics and space/time. How do we measure outside of space and time? What are we measuring for that matter? What does 'before', or 'cause' or 'effect' mean in such a reality?
As a self professed religious person, I believe there are subjective and unprovable answers. Others disagree and are happier with the questions. In either case it seems wise to not give up on looking.
I have determined that my sig is indeterminate.
Well, let's say the question is premature. Before you can ask it, you have to determine whether the question itself is based on false assumptions. This kind of question is tricky because questions you *can* ask meaningfully have the same syntax as questions which are meaningless.
For example, you can ask "What is colder than 0 degrees C?", but you can't ask "What is colder than 0 degrees K?". One question is meaningful and the other is not.
So asking "What happened before the Big Bang?", entails two assumptions, namely (1) the Big Bang happened and (2) the scientific consensus on the Big Bang is fundamentally flawed. If the scientific consensus is correct, then it's like asking, "What's colder than 0 degrees K?" or "What's north of the North Pole?"
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