dyna mo |
03-23-2015 03:25 PM |
Quote:
Originally Posted by Bladewire
(Post 20426760)
Yes, and this is the paradox you run into and why infinity only exists in mathematical theory, it's not real. At the end of the day you either believe a line can go on so far into forever that it passes over itself, or you don't. Infinite vs finite outside of theory.
In reference to using limits @ infinity in math. Infinity is still as endless, and the limit is used to stop there and say endlessness continues. Infinity is still endless.
Think about it logically, do you think and endless limit really exists? No
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like most miscommunications, we are on the same page, just coming at it from different angles.
here, see
you stated that
Quote:
Originally Posted by Bladewire
(Post 20426484)
The universe is finite. Infinite is used only in mathematics as an abstract concept.
If infinite expansion was a reality, then so would be infinite contraction.
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I expanded on that here:
Quote:
Originally Posted by dyna mo
(Post 20426496)
math is what explains the Universe though. and infinity is a limit in math, it's not actually infinity.
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my point being the the real limit in our understanding is math. and that's the math we (Einstein(s)) use to try and explain the Universe. Along those lines, it also is the limit that does not allow the math to explain the singularity prior to the BB. The reason for that is the math doesn't sort out infinity enough.
Here's an article that better states it:
Quote:
According to the Big Bang theory, the universe was born about 13.8 billion years ago. All the matter that exists today was once squished into an infinitely dense, infinitely tiny, ultra-hot point called a singularity. This tiny fireball then exploded and gave rise to the early universe.
The singularity comes out of the math of Einstein's theory of general relativity, which describes how mass warps space-time, and another equation (called Raychaudhuri's equation) that predicts whether the trajectory of something will converge or diverge over time. Going backward in time, according to these equations, all matter in the universe was once in a single point ? the Big Bang singularity.
But that's not quite true. In Einstein's formulation, the laws of physics actually break before the singularity is reached. But scientists extrapolate backward as if the physics equations still hold, said Robert Brandenberger, a theoretical cosmologist at McGill University in Montreal, who was not involved in the study.
"So when we say that the universe begins with a big bang, we really have no right to say that," Brandenberger told Live Science.
There are other problems brewing in physics ? namely, that the two most dominant theories, quantum mechanics and general relativity, can't be reconciled.
Quantum mechanics says that the behavior of tiny subatomic particles is fundamentally uncertain. This is at odds with Einstein's general relativity, which is deterministic, meaning that once all the natural laws are known, the future is completely predetermined by the past, Das said.
And neither theory explains what dark matter, an invisible form of matter that exerts a gravitational pull on ordinary matter but cannot be detected by most telescopes, is made of.
Quantum correction
Das and his colleagues wanted a way to resolve at least some of these problems. To do so, they looked at an older way of visualizing quantum mechanics, called Bohmian mechanics. In it, a hidden variable governs the bizarre behavior of subatomic particles. Unlike other formulations of quantum mechanics, it provides a way to calculate the trajectory of a particle.
Using this old-fashioned form of quantum theory, the researchers calculated a small correction term that could be included in Einstein's theory of general relativity. Then, they figured out what would happen in deep time. [8 Ways You Can See Einstein's Theory of Relativity in Real Life]
The upshot? In the new formulation, there is no singularity, and the universe is infinitely old.
A way to test the theory
One way of interpreting the quantum correction term in their equation is that it is related to the density of dark matter, Das said.
If so, the universe could be filled with a superfluid made of hypothetical particles, such as the gravity-carrying particles known as gravitons, or ultra-cold, ghostlike particles known as axions, Das said.
One way to test the theory is to look at how dark matter is distributed in the universe and see if it matches the properties of the proposed superfluid, Das said.
"If our results match with those, even approximately, that's great," Das told Live Science.
However, the new equations are just one way to reconcile quantum mechanics and general relativity. For instance, a part of string theory known as string gas cosmology predicts that the universe once had a long-lasting static phase, while other theories predict there was once a cosmic "bounce," where the universe first contracted until it reached a very small size, then began expanding, Brandenberg said.
Either way, the universe was once very, very small and hot.
"The fact that there's a hot fireball at very early times: that is confirmed," Brandenberg told Live Science. "When you try to go back all the way to the singularity, that's when the problems arise."
The new theory was explained in a paper published Feb. 4 in the journal Physical Letters B, and another paper that is currently under peer review, which was published in the preprint journal arXiv.
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Big Bang, Deflated? Universe May Have Had No Beginning
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