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Conditions necessary to form the first and simplest structures

  1. Dec 6, 2012 #1
    "In the minutes following the explosion, protons and neutrons collided in nuclear fusion reactions to form hydrogen and helium."

    I found this bit of text in an article...and it got me thinking.
    What were the conditions the first atoms formed?
    Further more..what were the conditions that made the neutrons,protons, electrons and other particles form.

    Even further i'm interested in the limit conditions right in the very moment, right before and right after the first atoms were formed and the conditions the very sub atomic particles formed.

    The way i see this is that the first stated minutes after the t=0 moment there was a great output of energy in different forms.
    For some reason the flow was asymetrical and areas of higher and lower density formed and interacted with eachother.
    Sometime in that period conditions allowed or perhaps a better word would be forced the formation of structures. Logic dictates that the structures were formed to conserve energy that was otherwise going to dissapear linearly and 1=0 would have been a true statement. It was due to the asymetry factor that structures were formed and the goal was to maintain energy levels as long as possible.

    I'm trying to immagine the following scenario:
    1. A medium of objects with inertia transmission very low...means compressing such a medium would not be possible by the objects inside this medium.
    2. The tendency is to decrease density but to conserve energy
    3. The first structures formed.
    Now here is where i think it gets interesting.
    Since the medium was not omogenous some areas allowed or forced the formation of structures...but the conditions varied. So...what happend to the FIRST STRUCTURE ever created? Is it still out there? or was it crushed back into the previous state sometime soon after its formation due to non omogenous areas that interacted with this FIRST structure?

    Another thought is:
    How much energy was consumed with the big bang?
    ok...the energy released we can see and approximate...but how much energy was used to contain and release this whole world? i'm guessing more than all the energy available in the universe.
  2. jcsd
  3. Dec 6, 2012 #2


    Staff: Mentor

    Steven Weinberg wrote a book called: The First Three Minutes that described the eveolution of the universe at inception. While some of it may be dated it may help to answer your questions.

    One key point is that the universe contains everything there is by definition and hence no energy can be acquired or lost only transformed from one type to another. (not sure how multi-verse theories address this)
  4. Dec 6, 2012 #3
    Thanks for the book name.
    Energy can be lost and is lost trough the inneficiency of the atomic and subatomic structures. They cant be perfect and some energy is used to keep the structure from colapsing into a lower state of energy. Without interaction from other higher energy systems, the system's energy will slowly decrease until the structure uses up all the available energy.
    I think this is the direction that the Big Freeze theory points.

    In my opinion the multiverse theory is just sci-fi.
  5. Dec 6, 2012 #4


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    This is incorrect. It takes zero energy to hold atomic and subatomic bonds together. Remember that energy is the ability to perform work. A book sitting on a table has zero worked performed on it and it takes no energy for the table to hold it up. Similarly the bonds between particles do not require work to hold them together. In fact, it is these bonds and the interaction through various forces that gives rise to energy and work in the first place! An atom in it's ground state is perfectly happy staying there forever, or until a rogue photon comes along and careens into it's electron cloud! Nasty little photons...
  6. Dec 7, 2012 #5
    hmm...a book and a table are not a system nor a structure

    The force forming and/or sustaining the atomic or subatomic structure is an effect of application of energy....think about it...why are they spinning around eachother in those exact trajectories and not in square trajectories? well yea...its to conserve energy..which energy? well the one they have inside the system.

    the question stands: what were the conditions of forming the first atomic and sub atomic structure and what happend to it after it was created.
  7. Dec 7, 2012 #6


    Staff: Mentor

    The best we can say during the creation of the universe is that a "bang" occurred, spacetime was created, photons coalesced into particles and then into hydrogen atoms. Formation of higher level atoms were due to supernova life cycle. Before the big bang spacetime did not exist.
  8. Dec 7, 2012 #7


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    Of course they are.

    No, you cannot apply energy. Energy is not a force. The fundamental forces give rise to energy, not the other way around. Bonds and orbitals don't care one bit about conservation of energy. They simply remain the way they are because you would have to perform work to alter them. Conservation of energy arises from this. You MUST perform work to change something, and energy is the ability to perform work. A stable molecule will remain stable not because of conservation of energy, but because nothing is making it change. I hope that makes sense.

    This should explain it: http://en.wikipedia.org/wiki/Timeline_of_the_big_bang
  9. Dec 15, 2012 #8
    i understand your point.

    so the structures are perpetum mobile? i'm an engineer and to me that sounds like...wizardry :)
    ok, so what makes the forces be? what makes the forces stable? ;)

    anyway...the question still stands: what would be the conditions when the first structures came to be. I'm interested in density, composition and the factors that crafted the structures the way they are and not some other way.
  10. Dec 15, 2012 #9


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    They are the fundamental forces of nature. They just are.

    The first "structures" could be either atoms or hadrons if you consider them to be structures, or the very first stars and galaxies that formed. Which ones are you referring to?
  11. Dec 15, 2012 #10
    This thread is not going in the direction i am interested in.
    What do you mean they just are? you're saying god just went click? :p
    The first structures are the first structures..what was created first in the timeframe? stars or hadrons?...duh...

    Anyone else chip in?
    There must be a certain set of conditions that lets say structures like hadrons can be created.
    For example...structures are created by stars at the end of their life...the output is more complex atomic structures.

    Can we make a comparisson between the violent death of a star and the big bang?
    Both are violent phenomena that accumulate energy into matter structures.
  12. Dec 15, 2012 #11


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    The stability of the atom is explained by quantum theory. Around the turn of the 20th century Bohr came up with the electron shell to replace the classical [Rutherford] model where electrons orbited the nucleus like planets orbit the sun. The orbital idea was clearly wrong because the atom would be unstable in this configuration. The quantified shell model, as it came to be known, solved this problem by requiring electrons to occupy shells surrounding the nucleus. The distance between shells is quantized like stair steps. When an electron gains energy, it jumps up a step, when it loses energy, it drops down a step and emits energy. Electrons are not infinitesimal points orbiting within a shell, they occupy it. The are effectively smeared out across the entire shell they happen to occupy.
  13. Dec 15, 2012 #12


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    We don't know. We can calculate how the different forces work but as for WHY they work the way the do we simply don't know. They just do. An electron always repels another electron because they are negatively charged. Why doesn't this change? We don't know. All we can say is that we have never observed a change in the fundamental forces.

    I don't know what you're saying here. I'm asking you what you mean as the first "structures".

    In the early universe we had extremely high energy photons being created from the annihilation of particles and antiparticles. These photons would then combine and create more particles and antiparticles that would then annihilate to produce more photons. It was one big cycle. The thing that changes was that the universe was expanding. We still don't know why it was or how it began.

    This expansion cooled off the photons and brought the density of the universe down until photons no longer had enough energy to create particles and antiparticles. At this point the remaining particles annihilated with the remaining antiparticles, with a small amount of normal particles being left over. We don't know why or how yet. It was right after this point that the first permanent "structures" formed if you want to call combinations of subatomic particles a structure.

    Is that what you mean by asking the conditions for structures to form?

    Yes, stars fuse light elements into heavier ones and massive stars undergo supernovas that create even heavier elements than iron.

    Not really. The big bang was not an explosion like a supernova. It's not really anything. It's a name given in error by a scientist that was against the theory that the universe was once in a very hot, very dense state and expanded over time, eventually reaching the point where we are today. This theory, because of this naming error, is known as the "Big Bang Theory". In reality the theory has nothing at all like an explosion that is commonly reported by most mainstream shows, books, etc. But a big explosion sounds cool and makes people want to buy something or watch a show.
  14. Dec 16, 2012 #13
    ofcourse i didnt mean stars as first structures :)

    regarding the why the forces are...it would make sense to be so because if the difference in the force carrying particle structure. meaning three sticks aligned is a different structure to two sticks aligned and one crossing them.
    So three sticks aligned will interact in one way with other three sticks aligned but three sticks aligned would interact in a totally different way with two sticks aligned and one crossing.
    does this make sense to you ?

    The comparison of a supernova with the big bang: i didnt mean to compare the names, but the process and output similarities. In both cases there is an acceleration of mass and generation of radiation. In both cases structures are created. i cant help to see the similarities.

    So in early universe we ONLY had high energy electromagnetic radiation? There was nothing else?
    If so..the conditions are: compressed high energy e.m. radiation and matter is then created?
    we should try that !

    i got the book !
    thanks again !
  15. Dec 16, 2012 #14


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    No, not at all. What are you trying to say with this analogy?

    There was no acceleration of mass in the big bang. The expansion of space does not result in "true" acceleration that one could measure with an accelerometer. In a supernova the opposite happens. There is definite acceleration of mass away from the star. You could say that in the early universe matter "accelerated' WITH spacetime, while in a supernova matter is accelerated separately of spacetime. (I don't want to argue what "true" acceleration means, I only define it this way to contrast the differences between the supernova and the expansion in the early universe)

    I can see how you can say they are similar, but you could say practically anything is similar to anything else in some manner.

    No, the early universe had both high energy radiation AND matter at the same time. Both annihilated with their antiparticles to form the other. (Photons are their own antiparticles)
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