Big Rip theory

Hello, kallcium.I'm a bit surprised that this was promoted without some editing requests. I think it's a fine topic, but some of your phrasing is a bit unclear. So please be patient if I miss any points you might be trying to make.-

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It says implys that the universe including Earth is continue to increase its acceleration not just a constant acceleration or slowing down like you might think it should if the big bang happened the way it did.

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Actually, what it implies is that the expansion of the universe is accelerating, not like the way one would think if gravity were the only force that is acting. But there are no reasons to thing that the force of gravity is the only large range force relevant to the expansion of the universe -- it was simply the simplest (and most reasonable) assumption to make based on what we knew previously.When Einstein first developed his General Theory of Relativity, he realized that his equations predicted a universe that was either expanding or contraction. Since at that time there was no evidence that the universe was anything other than static, he included ad hoc a term (the so called cosmological constant) to cancel out these effects so that a static universe would result.Then it was discovered that the universe is expanding after all, so it was eliminated.Now there is evidence that the rate of change of expansion is not what one would expect if the gravity were the sole determining factor. So people are reintroducing this cosmological constant to take this into account.At any rate, Big Bang is really a description of the early universe based on the observation that universe is expanding, and so must have been smaller in the past. There is nothing about Big Bang itself that determines the rate of change of expansion; rather the expansion is taken as a given (based on GR, of course, and the other laws of physics as currently understood). It may be, though, that this new "Dark Energy" (as this new force is called) may lead to new physical insights, and may change certain aspects of our understanding of the early universe.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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So what is causing these galaxies to increase its acceleration, in my opinion it couldn't be the big bang....

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Well, no, it couldn't, bacause "Big Bang" is a description of the early universe, not a "cause".What is "causing" this acceleration (if there is an acceleration; last I heard, it still needed confirmation) is a new scientific principle that was previously unknown.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

As far as I know, people are still working on it. All that is known is that some observations suggest that the expansion of the universe is acceleration.One idea is that space itself will repulse itself, so as the universe expands you have more space that will casue and even greater accereration, that will lead to more space, and greater acceleration, and so forth....Maybe our local cosmologists will have something to say once they notice this thread.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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To me it requires faith that it doesn't follow the the laws of physics.

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Indeed it would, which is why no one is saying that the early universe did not follow the laws of physics. In fact, what we think we understand about the early universe comes from applying the laws of physics (as we currently understand them) to the early universe.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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just is it requires an "equal and oppisite" faith the the big bang took care of that with the help of dark matter.

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Well, actually, big bang is a description of the early universe -- it doesn't "take care" of anything, no more than other "descriptions" "take care" of things.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

It may be that you are trying to make a point, but that I do not understand what your point is.Here is a description of Big Bang:It is observed that the galaxies are moving apart. The further away the galaxies are, the faster they are moving from us. The simplest explanation is that the universe (space itself) is expanding and carrying the galaxies apart. In fact, unless it is carefully doctored (with the addition of the so-called "csomological constant"), General Relativity itself says that the universe must be expanding or contraction.So, looking backwards, everything in the universe must have been closer together. According to the laws of physics, the universe must have been hotter as well. So, the universe, as we look further back in time, must have been hotter and denser.As we go further back in time, the universe must have been too hot and dense for stars or planets to exist, and, in fact, further back in time it must have been too hot and dense for atoms or even protons and neutrons to exist.If we extrapolate further back in time, we get to a point where the universe is infinitely hot and dense -- the so-called singularity, beyond which we cannot push our understanding because our laws of physics cannot handle these kinds of infinites. However, we cannot even approach this singularity, since as we push backwards in time, the universe becomes so hot and dense that our current understanding of physics is inadequate to deal with it. Scientists are working on new theories to push further back, but for now we can only speak of the universe so far back in time.So, the universe was once very hot and dense. The universe is expanding, and as it expanded it became cooler and less dense. This is pretty much Big Bang. Note that there is nothing about "explosions".Notice that these observations about an accelerated expansion do not change any of this in any significant way. According to the Big Bang model, the universe is expanding; this accelerated expansion just says that the rate of expansion is not what we thought it was. According to Big Bang, in the past the universe was very hot and very dense. These ideas of dark energy do not change that, either; even taking into account this dark energy (which is only a way of describing the accelerated expansion of the universe), we still believe that the universe was hot and dense in the past.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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There has to be....

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Be careful about exclaiming about what there has to be. If the advent of quantum mechanics and relativity theory has taught us anything, it is that the universe is a far stranger place than our intuition would indicate.-

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If it were infinitly hot and dense then today there would be an infinate amount of energy...

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No, just that the present amount of energy once occupied a very small volume. The energy density would be infinite, but not the energy.-

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...(heat is energy) which there is not as stated by the laws of thermodynamics.

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The laws of thermodynamics, like all the laws of physics, are descriptions of how the universe behaves based on the observations that we have made up to now. But the universe is not actually constrained to "obey" laws that we set up. Just like the universe does not obey Newton's "laws" of motion, future observations might show that the universe does not actually obey the laws of thermodynamics.-

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If you believe the universe was at one point infinately dense and hot....

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Actually, since our current understanding of the laws of physics do not allow us to describe the universe near the alleged singularity, we do not know if there even was a singularity. It may be that once quantum mechanics and general relativity are reconciled we will see that there was no singularity.And it may very well be that we will discover that the universe during this time when the universe was too hot and dense for our current understanding to describe had a very, very different history than we expect. Myself, I have philosophical reasons to hope that the history of the universe had no beginning -- that it has existed infinitely long ago in the past.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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No, it is simply the case that concepts like heat and energy begin to break down at the Big Bang.

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You mean that the concepts break down near the postulated singularity. "Big Bang" is the description of the history of the universe for its first several hundred years or so, and how that history determines what we see in the current universe.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

Kallcium, I have presented a brief description of what Big Bang is. Where is the implication that "matter is eternal"?

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

Heh. I'm just trying to defuse the "Big Bang says the universe exploded from nothing" notion.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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Later, the cosmic background radiation was measured, this time confirming the prediction that the universe was much hotter and denser in the past, viz. The Big Bang.

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And it also should be noted that the relative abundances of nucleotides (particularly 1H, 4He, 3He, 2H and 7Li) are consistent with the Big Bang model. I believe that certain parameters were adjusted to fit the observed abundances so this may not count as a prediction of Big Bang, but it would have been easy for the demiurge to have created these elements in abundances that are completely inconsistent with any reasonable Big Bang scenario.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

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What i find interesting is if Energy can not be made or destroyed then where did all the Energy in the universe come from[?]

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A few possibilities:1) Energy can be created (and perhaps destroyed).2) There is no "t=0" beginning of time; the universe has always existed, and so has energy (and matter).3) There is a "t=0" before which there is no history; however, the universe simply exists as a self-contained 4-manifold; that is, the universe, and all the energy and matter contained within it, simply exist. Energy was not created, since there was never a time at which there was no energy.Probably other possibilities as well.

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt