I repeat "Everything is speculation when it comes to that."
"Indeed, there is a great deal of speculation on the subject, with different theories about how the universe began, and what may have existed before the universe came into being."
Everything about the Big Bang is speculation (and there was no bang, btw...no explosion. Nobody can explain the theory of the Big Bang. One theory looks at an endless cycle of bangs and crunches:
space.com
"Paul Steinhardt's universe is a lot like the workaday world of many people, a cycle of early vigor, spent energy, exhausted return, and new beginnings. However, in Steinhardt's universe, there is absolutely no end to the cycle.
The Princeton physicist and his colleague, Neil Turok of Cambridge University, have developed a whole new theory for how the universe came to be. Their proposal seeks to explain recently uncovered flaws in the scientifically accepted model for the origin and evolution of all known things. It describes a series of big bangs and equally significant crunches that form a never-ending cycle of rejuvenation and destruction.
In this universe -- our universe -- time never ends.
The current leading theory for the universe holds that it emerged from a single Big Bang sometime around 12 billion to 15 billion years ago, undergoing an early and rapid period of inflation. That much remains widely accepted.
"However, the standard model has some cracks," Steinhardt and Turok write in a paper published today in the online version of the journal Science.
Astronomers have in recent years learned that the universe is not just expanding, but is doing so at an ever-increasing pace. This can't be explained given the known matter and energy that exists. To account for the acceleration, theorists have conjured a product they call dark energy, which supposedly repels things rather than attracting, as gravity does.
No one has seen this dark energy, and scientists don't even know what it is. But they say it's all around us.
More important, it shouldn't be there.
"The recent discoveries of cosmic acceleration and gravitationally self-repulsive dark energy were not predicted and have no particular role in the standard model," Steinhardt and Turok argue. "Furthermore, the standard model does not explain the beginning of time,' the initial conditions of the universe, or what will happen in the long-term future."
So to patch some of the theoretical cracks, Steinhardt and Turok envision a universe based on perpetual expansion and contraction.
Here's how it works, and keep in mind we're jumping into the middle of the explanation: A big bang sends everything outward. Matter and radiation develop. Dark energy drives an expansion -- as is presently underway -- that lasts trillions of years. Finally, the matter, radiation, and even black holes are "diluted away," leaving the universe smooth, empty, and flat.
Then everything contracts in a so-called big crunch, and a fresh cycle begins.
"In this picture, space and time exist forever, Steinhardt says. "The big bang is not the beginning of time. Rather, it is a bridge to a pre-existing contracting era."
Curiously, the cyclic universe, as it is called, puts the origin of some present-day structures and events prior to the Big Bang.
While existing theory states that galaxies and large clusters of galaxies developed from lumps and filaments that formed in the otherwise smooth fabric of space and time shortly after the Big Bang, Steinhardt thinks the seeds of galaxy formation were created by instabilities that arose during the last contraction, before the crunch that led to "our" bang.
The new model "turns the conventional picture topsy-turvy," he says.
The cyclic universe has roots in even more complex thoughts like so-called superstring theory, which suggests there are as many as 10 spatial dimensions, not just the three we know of. The seemingly inexplicable physics of a big crunch and a big bang might be explained with the aid of these extra dimensions, which are otherwise invisible to us, several theorists believe.
In fact, Steinhardt, Turok and others proposed last year that our universe might have sprung from the collapse of an extra dimension, an idea they called the Ekpyrotic Universe. The cyclic universe builds on this former work but, Steinhardt says, does a better job explaining observations of our present universe.
Other theorists are not quick to give up their standard model, so the concept of a cyclic universe faces an uphill battle for prominence. Even Steinhardt acknowledges that the prospect of unseating a well established cosmological theory "would seem extremely dim."
Meanwhile, the new concept is not free of cracks, either: Even the cyclic universe does not address when the cycles began, so "the problem of explaining the beginning of time remains," the researchers say."
ANOTHER (THE BOUNCE THEORY) is more SPECULATION:
physorg.com
"One of the most interesting questions considered by astrophysicists deals with the start of our universe. Indeed, there is a great deal of speculation on the subject, with different theories about how the universe began, and what may have existed before the universe came into being.
Several prominent astrophysicists around the world are interested in answering these questions. In one paper, “No-Boundary Measure of the Universe,” published in Physical Review Letters, James Hartle, Stephen Hawking and Thomas Hertog calculate the probabilities that the no-boundary wave function predicts in terms of classical space-time possibilities.
“Theories regarding the beginning of the universe are expressed as wave functions,” Hartle tells PhysOrg.com. “The no-boundary wave function is one theory about the origins of the universe.” The goal of this particular work with Hawking and Hertog, he continues, was to model the universe and see what kind of probabilities exist that the current universe could have originated in a certain way.
The no-boundary proposal predicts that expansion in the early universe would have proceeded smoothly from a moment in time. The idea is that inflation was a feature of our early universe. “It collapsed from a previous large phase, bounced at a small but not zero radius, and expanded again to the large phase we are living in,” says Hartle.
The no-boundary wave function also states that space-time was not what we see today at the outset of universal expansion. “When the universe started out,” Hartle explains, “there wasn’t ordinary space-time. Instead of three space directions, as we have now, there were four space directions. At some point, a transition was made to ordinary space-time.”
Hartle and his colleagues examined models of the universe that were homogenous, isotropic and closed. A cosmological constant was assumed, as was a scalar field with quadratic potential. They looked at entire classical histories, examining the ideas of a singularity, such as a Big Bang, or considering a bounce with a finite radius. The point was to get a picture of which scenarios are most likely to produce a universe that is similar to what we see currently.
“Both things, a Big Bang or a bounce, are possible,” Hartle says. “However, we found a significant probability that the early universe might have bounced.”
Hartle does admit that the simple model used by him and his colleagues does have its limitations. For one thing, the universe is not completely homogenous as the model assumes. “You see a certain lumpiness in the real universe,” he concedes. However, most of the irregularities are small, and many of them can, in fact, be ultimately accounted for in a no-boundary proposal.
“Our model does make a number of strong assumptions,” Hartle continues. But, he insists, “this is a standard trade-off in physics. Our model is simplified so that we can analyze it completely.”
“In present cosmology, we test models to see if different proposals fit the universe that we see. In this instance, we see that the no-boundary wave function does,” Hartle says. “We see that there is a good chance the universe originated in a bounce.”
“We hope that can extend this to other, more sophisticated models, with different potentials and different degrees of freedom.”
Copyright 2008 PhysOrg.com.
________________
Are you arguing for a self caused initial cause?
I'm not arguing "FOR" anything! It is an awesome universe and we know (as I have stated before) as much as a grain of sand knows about the beach. People of intelligence recognize and acknowledge that their ideas about the universe are vast SPECULATIONS. It is the dummies of the world (such as yourself) wou substitute absurd myth for speculation and wrap it in the DUMMY cloak of Absolute Truth!
"The cause of the universe is either Personal or it is impersonal."
LOL!! Nobody knows anything about that! If we knew the answer to such a question we would then have to ask whether the cause of the "personal" or the "impersonal;" was either personal or impersonal and we would continue to mutter this inane nonsense till the next crunch and the next Big Bang!
"So you are a liar as well as an egomaniac!"
LOL! I am neither! There is a chance that your IQ hovers around 80 and I am not a liar over a few points! Some small hyperbole serves to emphasis just how ignorant and absurd your cocksure attitude appears in the face of the facts and when juxtaposed with sound reason. It also isolates your childish pique for the observation and perhaps the sympathy of others... |
