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stan hummel

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Does anyone understand the Big Bang theory?

It is said that the theory of relativity is understood by several people (or a few more)... but i'm curious if anyone understands the Big Bang theory (+Infation). because it isn't so obvious at all.
why i think so, don't know exactly... just suppose... but assure nobody is going to refute this theory! just a few small doubts.
but the real problem is... do we really fully understand what it all might mean?
however (for facilitation) we won't be considering fates of the entire universe.
rather more interesting is what happens with us... real issue is the fate of our lost mind.
At the beginning we have something very small. our future universe is not the size of galaxy, earth, grain of sand... is much more tiny... just a POINT!
But the essence of this consideration is not vanity or divinity that point.
The real problem is moment (or thought process) in which the Real Universe turns into a Mathematical Universe.
know, it isn't easy to understand with such a modest possibilities of our mind.
however, if seems to us it's absolutely not a problem, just a logical consequence... so we probably have already crossed the border! but it's quite other story!
so how we are supposed to understand the universe when we don't have the slightest idea what we want to understand?


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    Jun 13 2013: I don't understand why anyone would believe in the Big Bang; however lots of smart folk do. So perhaps one of them could enlighten me.
    Do the Gas Laws apply in outer space ?
    If not, why not ?
    If yes, then why should we think that hydrogen atoms are attracted by their gravity to give birth to stars ?
    Simple question; not been easy to get an answer, so far.

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      Jun 13 2013: You haven't been able to get an explanation on the creation of stars!?

      Which Gas Laws are you referring to? have you read up on it? http://en.wikipedia.org/wiki/Gas_laws

      And here's the explanation for the creation of stars: http://abyss.uoregon.edu/~js/ast122/lectures/lec12.html

      (I do not understand how anyone can really think that the earth is 6000 years old)
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        Jun 13 2013: Hi Jimmy

        From your first link.
        This is known as Boyle's law which states: the volume of a given mass of gas is inversely proportional to its pressure, if the temperature remains constant. Mathematically this is:
        where k is a constant (i.e. NOT Boltzmann's constant).

        From your second link
        Stars form from clouds of gas and collapse under self-gravity. The collapse is stopped by internal pressure in the core of the star. During the collapse, the potential energy of infalling hydrogen atoms is converted to kinetic energy, heating the core. As the temperature goes up, the pressure goes up to stop the collapse.

        On earth the volume of a gas increases as the pressure decreases until pressure is ambient. Ie atmospheric, 14psi ish. In space the ambient pressure is zero ish. Therefore the gas will expand forever ish.
        On earth the inherent gravity in the hydrogen atoms is much less than the repellent forces, so the gas expands. I see no reason for space to be different.

        Yes, I have read up on it.
        The age of the earth has no effect on the problem.

        • Jun 13 2013: Is space different than on earth. No, but then space is mostly empty and even the densest nebula is still better than our best vacuums.
          Stars tend to be created in clusters where there are 10's of thousands of solar masses in one spot.
          Although the possibility of a uniform material self collapsing under its own gravity is possible is seems to be not likely. A shock wave from a nearby exploding star would be a good enough trigger after which gravity would take over.
          How did the first stars get started then?
          The expansion of the universe appears not to be uniform and the density differentials are enough to start gravity collapsing hydrogen into stars which would kick start the rest of creation.
          Don't forget that stellar nurseries are also areas of dark mater which makes the dynamics more difficult to understand.
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          Jun 13 2013: space is very different than on earth in some aspects. try going up there without a suit. gas laws suck your lungs right out your mouth. We have atmosphere. We have air pressure. We have gravitational resistance. We have air resistance. We have friction. Space does not. You find nothing to contradict creationism because none of these things have anything to even do with the earth supposedly being 6000 years old.
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        Jun 14 2013: Hi Gordon,

        ""No, but then space is mostly empty and even the densest nebula is still better than our best vacuums""
        That would make gravitational collapse even less likely.

        ""Stars tend to be created in clusters where there are 10's of thousands of solar masses in one spot.""
        What is the evidence for even one star being 'created' ?

        ""A shock wave from a nearby exploding star would be a good enough trigger a....""
        I've heard tis said, but also that it would take 3 or 4 surrounding the gas to go off at once. It's not gonna happen.

        ""...the density differentials are enough to start gravity collapsing hydrogen into stars which would kick start the rest of creation.""
        All the atoms are hurtling away fro a common source. By definition they are getting further from each other. There is no force in this process which would encourage this hypothetical collapse.

        Dark Matter is a totally imaginary mathematical convenience. However if it existed, it would be everywhere & have little effect on the Gas Laws.

        @ Brendan.
        You didn't address the question.

        Come on Big Bangers. If you believe this happened, surely you have satisfactorily thought through this problem.

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          Jun 15 2013: Peter why don't the gas laws apply to the sun and all the hydrogen etc float off as you seem to be implying. Gravity I guess.
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        Jun 15 2013: Hi Obey.
        For the same reason that the atmosphere doesn't leave earth. The earth has a gravitational pull on the gases. If the earth was to disappear you may be sure the atmospheric gases would waste no time in dispersing.
        Likewise the sun. The sun has a large mass exerting a gravitational pull on the surrounding gases. No one really knows, but I would bet that the sun is not merely a ball of gas.

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          Jun 17 2013: I'm still not seeing how gas laws even have anything to do with the big bang theory.
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        Jun 17 2013: Hi Brendan,
        The matter formed by the BB is postulated to be hydrogen gas. The other elements were supposedly made in stars. These stars were allegedly formed by the hydrogen clumping together by gravitational forces. You know the trouble we have compressing gas; it does not readily compress, it naturally tries to disperse. The gas laws are based on this inherent property of all gases. My quest is to try & understand why we think gas should compress spontaneously into stars in outer space, when the Gas Laws would appear to prohibit this.

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          Jun 18 2013: Thanks Peter, I think I finally got what you're asking. Correct you are that the first atom is supposedly hydrogen. Shortly after came helium. What actually happened is that a few of the elements, not just hydrogen, came from the big bang, and then all of those compressed differently to form different stars which is why we see nebulae forming. Gravity was able to still bring them together because they were still so close to each other.

          Nebulae are baby stars so to speak. They are the process of these gases slowly coming together and when they do, it is like a huge nuclear reactor in the core. They had so much energy that they kept getting bigger and were so hot that they could make even newer elements. Some of it escapes the star and cools into dust, which is what came to form planets, asteroids, etc.
    • Jun 15 2013: The gas laws are about smallish quantities of gas, where the gravitation of the gas is so small that ignoring it did not cause trouble. Stars and such from where there's such amounts of gas that they have enough gravitation to collapse. I truly can't understand why would people think that mathematical equations describing how gases behave in our little planet (the gas laws), would apply to quantities that Boyle, for example, never worked with.

      Even those laws are referred to as laws for "ideal gases" because they describe tendencies, but those people knew that real gases had their caveats due for example, to different atomic sizes, polarities in the molecules, et cetera, and that big quantities did not behave that uniformly. Just look at our atmosphere. Quite the complex behaviour (due to many factors, but also because of quantity). Also, our atmosphere has not completely escaped away because of gravitation. Nobody has put our planet's gravitation in jail form breaking the gas laws so far. Anyway, factors other than the general tendencies described by those laws have to be taken into consideration, and the enormous gravitation of enormous amounts of hydrogen are no joke.

      That's it. Easy: gravitation.

      P.S. I hope nobody has forgotten that even changes in gravitation and atmospheric pressure at different altitudes influence stuff enough that behaviour at sea level is used as standard.
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        Jun 15 2013: Hi Entropy,
        I don't remember reading anywhere that gas laws only apply to "smallish quantities of gas". Presumably the repellant forces between the atoms are magnetic, I don't know. However if the gravitational attraction is A, and the repellant force is 2A, then they are never going to attract. Also bear in mind that these atoms are rushing away from a common source, so their momentum is carrying them away from each other. Gravitational force between 2 atoms is negligible anyway, but at a few inches separation will be non-existent.
        The atmosphere is a totally different case. The mass of the earth is strong enough to exert a gravitational force on the atoms in the atmosphere; although I think the lighter gases can even escape that.
        All the textbooks give gravitation as the cause; along with exploding stars etc., but none have explained just how it overcomes the repellant forces.
        Beats me how folks can have such faith in the BB & yet this fundamental point has not been addressed. Sometimes we have to admit we don't know; but I guess funding is hard to come by without coming up with answers. :)

    • Jun 15 2013: It is not that gas laws are only applicable to smallish quantities of gas. It is that gas laws describe each only one kind of phenomena. The phenomena where they were developed, mostly the industrial revolution dealing with steam machinery and such. Obviously, they would teach you this in high school, and in engineering, since you need those mathematical formulations in your everyday job, which does not involve dealing with gases in stars. Even then those laws are not taken in isolation. Each describes one tendency, but to properly understand a system you have to consider more variables depending on the expected effect. Gas laws are approximations to ideal conditions for ideal gases that ignore other forces because the approximations suffice for certain problems.

      The filling of a vacuo in "normal", earthly, situations, is not due to repulsion between the molecules, but to kinetic energy and not enough attraction between molecules (too few). In your formulation you should therefore forget about repulsion until the molecules are very, but very, close. So you are left with gravitation. Now, remember that the gravitation is due to all the molecules, all the molecules attract each other. It's not a 1 to 1 thing. To illustrate, if we had this line of molecules:


      The one farthest to the right would be "feeling" the attraction from all the ones to its left. Less from the farthest one and more from the closest one, but still attraction from all of them. This is true for all the molecules. Overall, the forces are almost nothing in small quantities, but in huge quantities they are enough to have the system collapse onto itself. Once molecules are too close then there's repulsion, but if there's enough gravitation we get lots of interesting stuff going on, like stars.

      I hope that was clear enough.
    • Jun 15 2013: A few more points:

      1. The atmosphere is not a totally different case. Gravitation is gravitation is gravitation. No matter if it's exerted by a planet or by huge amounts of gas molecules.

      2. I am not "Big Banger" and I do not accept the Big Bang out of faith. I accept it as the current explanation given the current evidence. I would not care one bit if it turned out to be completely false. There's lots of open questions about the Big Bang, but Boyle's law has never been one of them.

      3. Now I see that the link provided by Jimmy already explained a lot. Here it goes again: http://abyss.uoregon.edu/~js/ast122/lectures/lec12.html
    • Jun 15 2013: Hi Peter,

      You are demonstrating some very good critical thinking. You have certainly demonstrated that the physicists have done a bad job of explaining the Big Bang.

      The "repellent force" in a gas is ordinary heat, the kinetic force of the movement of the molecules.

      The BB explanations that I have read and viewed say that expansion of the universe cools the gasses to near absolute zero, when the force of gravity, the total gravity of the gas clouds, overcomes the kinetic force of the molecules, eventually causing collapse into stars. To make the math work they had to invent an inflationary period, of unknown cause, during which the universe expands at an accelerated rate. I have never seen or heard any explanation for the origin or role of dark matter in the early stages of the Big Bang.

      I am not supporting the BB, just trying to add to the discussion. The BB seems plausible in some respects, but it does seem that it requires a lot of fudging to explain the universe that we see around us. That could be due to very basic flaws in the theory, or it might be due to physicists with poor communication skills. I try to keep an open mind. We are looking at the observable universe through a very tiny window.
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        Jun 15 2013: Hi Barry.
        Thanks for the info. Heat is the repellant force. That makes sense although this must be at a lesser temperature than, say steam. Heat manifests itself as vibration, so the atoms kind of bounce off of each other; is that right?
        So these atoms are rushing away from a common point at colossal speed. There is nothing to slow them, nothing to cool them. By the time they cool to absolute zero are they not going to be many miles appart? Let's say not, & they get attracted by gravity. As soon as they come into close proximity is not the temperature going to rise & the gas laws reinstated. I assume this is the case as scientists have postulated various exploding star scenarios to regain credibility.
        All this seems to stem from the Red Shift which is translated as an expanding universe. There are other possible causes of the red shift. Maybe we got that right, but extrapolating all the way back to a single point seems a stretch in itself.
        I don't think anyone understands the BB. But lots of professionals have a vested interest in claiming they do.

        • Jun 16 2013: As I understand it:

          The big bang was not an explosion, just an expansion in which space itself was expanding.. The best explanation for this that I have found is at this site:

          The main force that caused the deceleration of the of particles was the total gravity of the universe. Since the total volume of the universe at that time was much less than it is today, the effect of gravity was much greater. For the same reason, the particles were not necessarily miles apart. I have been trying to find an estimate of the temperature of the universe at the point when hydrogen molecules started to collapse into stars, but so for have had no success.

          "I don't think anyone understands the BB. But lots of professionals have a vested interest in claiming they do."

          After looking at many web pages about the big bang theory, and finding very little information about the formation of the first stars, I can understand why you think this. That point in the evolution of the universe is critical to the theory. One of the assumptions of the theory is that matter was distributed fairly uniformly at that point in time. That implies that the first generation of stars were all of roughly the same size. If the first stars were all small, there would never have been any supernovas and the universe would not look anything like what we observe today. Similarly, if the first generation were all super massive, today's universe would be impossible. So the fact that the universe looks as it does means that the first generation of stars must have had a predominance of medium sized stars. In turn, that indicates that the temperature and density of the universe must have been within calculable limits.

          So, based on the big bang theory, it should be possible to calculate that temperature and density in two ways, going from the BB forward, and starting with the current universe and going backward. Are the two calculations compatible?
        • Jun 16 2013: This seems to be the kind of equation to look for Peter:

          Gravitation and pressure are taken into consideration. As I said, Boyle never presented a problem for the formation of stars.

          As per Big Bang itself, it is not an explosion of material into empty space, it is an expansion where space itself expands. The energy at the beginning was so immense that there was no hydrogen yet. Not even neutrons and protons, but some sort of plasma. What would cool it down? Expansion itself. The same amount of energy in a bigger space means less temperature. Space was so small and hot when the first protons and neutrons formed, that many reacted and formed helium-4 by nuclear fusion. WIkipedia has a good primer on the [proposed] stages of the Big Bang (some better supported than others, of course, scientists don't know everything):

          In order to understand the Big Bang, you have to go to resources that explain as many details as you are interested in, at least up to the point where you would have to study nuclear physics. However, attempting to understand it from Earth-like experiences and too basic an understanding of such things as Boyle's laws, or imagining that the Big Bang was an explosion of packed hydrogen atoms, won't help you much.

          There's only so much that can be explained in a forum like this. Anything else is up to you.

          See ya.
      • Jun 16 2013: Unfortunately, creationists seem to be much more interested in figuring out ways to deny any science that contradicts their beliefs than in reasoning whether the points they try and make really make anything against those sciences. Here Peter attempts to use middle-school simplified science (at best), mixed with mere arithmetic, for problems that demand advanced math and proper understanding of physics.

        If Boyle's laws were a problem for the Big Bang, then physicists would already know that, and would have either abandoned the idea, or there would be loads and loads of articles saying how Boyle's laws won't allow for star formation. Yet, I did not find a single reference saying that because of Boyle's laws, stars should never form. Not a single reference saying that gases don's have gravitation. Given that I am the ignorant, were I to propose that Boyle's law is a problem, I would have no option but to think that either my understanding of Boyle's laws and of gravitation are wrong, or there's something I am not taking into account. I would therefore check as much information as possible. Probably find those description that say that gas laws apply under certain circumstances and that other forces have to be taken into account, etcetera.

        But creationists think the other way around. If semi-understood middle-school physics give them an opportunity to deny science, they use it no matter how ignorant they might look.

        Me? I admit my ignorance every single time and go try and figure things out before opening my big mouth. If I am still convinced, I still present my ideas humbly admitting that there might be something I'm missing. Even within my own area of research, when my results conflict with those from other people I ask if there is something I'm missing.

        The Big Bang is not a complete model. It's just the best model so far. That does not mean that it has middle-school-level problems.
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      Jun 15 2013: To keep it short and sweet, it's not an explosion. It was an expansion. The end. That's how it happened. I don't see what else there could be to ask. It expanded into what we know of today.

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