Big Bang Theory and selected comments

These are selected post from a thread at SciForum titled "The Cause of the Big Bang". I entered the thread after eight pages and jumped in to put in my thoughts: quantum_wave 08-02-08 05:07 PM -------------------------------------------------------------------------------- I did try to read the whole thread but when I took a peek at the last page I saw the convenient summary by my buddy honcho and decided to skip the "you suck" sh$t and jump in since the cause of the BB is one of my favorite topics :shrug:. Lately you are becoming a part of a rare breed if you insist that BBT shouldn't be questioned, and especially if you insist the on a zero volume infinitely dense onetime starting point 13.7 billion years ago. What ever started the Big Bang expansion or what ever the pre-conditions were, our complete universe as an infinitely dense zero volume singularity is pretty hard to substantiate. My position is that students should be taught BBT, General Relativity, the Cosmological Principle as part of their general science education. Fine, because BBT is the standard and most widely supported theory, the best science can do without speculating about new physics, new evidence, etc. But my position also is that there isn't any great pillar of BBT that isn't without its problems. You name the pillar whether it is GR, the Cosmological Principle, CMBR, WMAP, inflation, nucleosynthesis, the red shift and Hubble constant, the cause of the big bang, the cause of expansion, the cause of accelerating expansion, and the explanation or lack thereof of galaxy formation and movement. As an observer my opinion is that there will be a solution to the incompatibility of GR and quantum mechanics someday so maybe we will all know if there was a "before" the big bang or the cause of the expansion and accelerating expansion that we observe. Let me address the question of new space, i.e. the volume of space increasing as expansion of the big bang universe proceeds. The big argument for this premise is that it is the only plausible explanation for the kind of expansion that we observe, i.e. everything is moving away from everything else at the galactic level (aside from some local clusters of galaxies). That premise might very well be true and if it is then BBT might very well be correct and new space is being created by the expansion, but there is another explanation for the co-moving expansion that is observed that supports the premise that space already existed and that the observable universe is expanding into space that was already there. Prior to matter formation and gravity being exerted by mass there was supposed to be exponential expansion of the budding universe. This inflation is necessary to make a connection between the causal event and what we observe today. Without exponential expansion in the first instant, before the matter formation and the start of photon emissions from matter, there wouldn't have been enough time passed yet to cause the consistent background temperature of the cosmic microwave background. So if expansion was underway when matter formed then when matter formed it had relative momentum imparted to it as it formed. Even though local gravity affected local matter, all structure that formed from the first matter would have the momentum of the initial expansion imparted to it, so all structure like say galaxies that formed would be moving away from all other galaxies because of the conservation of the initial momentum of matter. This means that the space that the galaxies are expanding into could have always existed. I’m not saying there is any proof, but the evidence of expansion supports this scenario even if the Big Bang and nucleosynthesis happened as the standard theory predicts. Maybe space was already there when the expansion began and when the CMBR was emitted :eek:. quantum_wave 08-03-08 01:48 PM -------------------------------------------------------------------------------- Let me address another pillar of Big Bang Theory, the Cosmological Principle. It fits nicely with General Relativity to form a solid basis for BBT. Simply put, the Cosmological Principle states that the entire universe looks pretty much the same everywhere and no matter where you are in it, everything seems to be moving away from everything else in a similar fashion at the overall galactic level. Though it is true that some very large scale is delectable in the cosmic microwave background that structure can be attributed to quantum fluctuations in the early universe and could have resulted in a variety of large scale structure patterns, so the pattern that we observe has no special significance and doesn't detract from the overall homogeneity. Even with the coincidental large structure that we observe, everything is moving away from everything else and we cannot detect an edge or a center of expansion. Under these circumstances which are in accord with BBT, the Cosmological Principle is in tact. But if my alternative premise to the "new space" pillar of BBT as stated in the previous post were correct, then would the Cosmological Principle apply to the greater universe that consists of infinite space that has always existed? We don't have much to go on but our observable universe is expanding and the expansion is accelerating. The expansion is thought to have begun 13.7 billion years ago and the expanding universe, our arena in infinite space as it then would be, is considered finite in content. General Relativity is track-able and when backtracked it reaches its tiniest dimensions about 13.7 billion years ago. Under the premise that space already existed then the entire arena of our known universe occupied the tiniest of spaces within the existing infinite space, a big crunch. That would not comply with the Cosmological principle because a single tiny infinitely dense entity like our arena some 13.7 billion years ago, sitting alone in space, would actually have to be considered inhomogeneous and not isotropic. You might even have to consider it the center of the universe. But the thing that brings the Cosmological Principle back into play is the finite nature of our arena (our expanding universe). If infinite space was very much like the space that contains our expanding universe, then it would still be homogeneous if every where we looked we could see other similar arenas playing out where some were contracting into big crunches, some crunches had burst into expansion, and some had experienced the complete disbursal of their contents in the form of receding galaxies out into the greater universe. Under those homogeneous conditions, isotropy would again come into play because in all directions we would see crunches forming, bursting and disbursing without any preferred direction, without any edge, and without any detectable center in the greater universe. quantum_wave 08-04-08 09:33 AM -------------------------------------------------------------------------------- While I’m at it I may as well mention vacuum energy known as negative energy density and better known as the cosmological constant. The current debate among BBT enthusiasts is what the value of lambda (the cosmological constant) is. If the universe was flat, i.e. meaning it will not collapse and it will not proceed to a Big Rip, then the value of lambda would be 1. Current estimates based on the apparent accelerating expansion indicate a positive lambda and a negative overall energy density. The interesting thing about lambda is that it is a constant and as the universe expands and the energy density of the universe declines, the constant remains … well, constant. The implication is that if we are expanding due to a positive lambda, we will continue to expand until the ultimate fate of expansion is realized in the form of what is called the Big Rip or the heat death of the universe. It is a chilling prospect but it would take a long time so we talk about it in a kind of unconcerned acknowledgment. If what I posted about the creation of space, and if the theory that new space comes into existence as the universe expands then there is nothing to stop expansion, the energy density of the universe will continue to decline and will approach the limit of zero. Yikes, really cold. On the other hand, if space always existed and we simply occupy an arena of finite matter and energy expanding into existing space there still would be a Big Rip in our future. But if the suggestion that I made about our finite arena being only one of a potentially infinite number of arenas within infinite space that had always existed, then we can forget about a Big Rip because the complete entropy of the rip would be defeated by the infinite landscape of the greater universe. That would make the universe capable of continuing to support life forever, and would also imply that it has always existed and probably then would have always supported life. kaneda 08-04-08 11:12 AM -------------------------------------------------------------------------------- Quote: -------------------------------------------------------------------------------- Originally Posted by quantum_wave (Post 1950922) Maybe space was already there when the expansion began and when the CMBR was emitted :eek:. -------------------------------------------------------------------------------- A number of BB problems would be solved if there has been a previous universe which didn't fully collapse before it expanded again. quantum_wave 08-04-08 11:23 AM -------------------------------------------------------------------------------- Quote: -------------------------------------------------------------------------------- Originally Posted by kaneda (Post 1954558) A number of BB problems would be solved if there has been a previous universe which didn't fully collapse before it expanded again. -------------------------------------------------------------------------------- This is true. That is what you and I understand and what I tried to show with my few posts on this thread. Anyone who won't acknowledge that a greater universe exists surrounding our expanding observable universe is pretty much stuck in BBT. Probably a good place for them given its eventually outcome :). quantum_wave 08-04-08 05:43 PM -------------------------------------------------------------------------------- Of course the primary pillar of the Big Bang Theory is General Relativity. It is a thing of beauty in its ability to explain the movement of objects in spacetime and to predict those movements. It features the coupling of space and time, it describes mass in terms of its energy equivalent, and it uses the curvature of spacetime associated with mass to define the effect of gravity and predict the movements of objects in space. It is a mathematical model that tracks the Big Bang universe from the instant after the Big Bang until now and into the future as far as you might want to go. It can be described as a co-moving coordinate system that displays the inflation of the universe as new space is added to the universe as it expands. I have supported BBT as the standard cosmology and have supported it being taught as part of a student’s basic science education. I also pointed out that it was the best science could do with the current evidence and without speculating about as yet undiscovered physics. But I also support teaching it as theory and mentioning alternative theories. In that regard I made three recent posts on this thread about the pillars of Big Bang Theory where I suggested alternatives. I pointed out an alternative to the creation of new space and that there is a possibility that space already existed before the big bang occurred. I mentioned that suggestion combined with the finite nature of our expanding universe and keeping the cosmological principle intact suggests that the greater universe could infinite and cosmologically flat with a lambda of 1, and could be filled with a potentially infinite number of arenas similar to our own expanding arena. Now I want to suggest that though the movement of objects under the influence of gravity is almost perfectly described by General Relativity, the movement of objects in space does not require space and time to be coupled and it does not require the fabric of spacetime to be warped by mass. How can I be so audacious? It is easy. Objects move through space as if space was curved by mass. But if gravity reaches across space to affect distant objects, those objects would also move as if space was curved because gravity travels at near the speed of light and by the time it reaches and effects distant objects, the source object has changed location. This results in a curved effect between observed objects caused by gravity waves that travel as expanding spherical waves. The wave reaches the object and gives it a little tug toward the location that the first object occupied when the wave was emitted. An instant later the next wave reaches the object and gives it a little tug toward a slightly different location that was occupied by the first object as the second wave was emitted an instant after the first wave. Follow this procedure over time and you will get a curved movement of objects due to their relative movement and the propagation speed of spherical gravity waves, not due to the warped fabric of spacetime. Quantum scientists are looking hard for the Higgs boson and a Higgs field that would convey the force of gravity across space but they aren’t claiming that the discovery of the boson will change the way we calculate the effect of gravity. I expect we will be using Einstein’s field equations for that purpose for a long time. But the discovery of the Higgs boson or some other cause of gravity and field will add a feature to the universe that has been discounted since the Michelson–Morley experiments. That feature is referred to as aether, or a gravity field or energy background to the universe across which gravity waves can travel. If they find it the implications are that though General Relativity has done a fine job of describing the effect of gravity, it was wrong about the coupling of spacetime and the warping of the spacetime fabric by mass. Mass and gravity will become linked by the gravity waves emitted by mass as a characteristic of mass itself and not as a characteristic of curved space. And at the same time the incompatibility issue between quantum mechanics and General Relativity will be resolved in favor of quantum mechanics.