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Was matter created during the big bang?

  1. Apr 8, 2014 #1
    I'm trying to get a basic understanding of the big bang in order to teach an advanced oceanography course to high school students this summer. The course starts with one lecture on the origins of the universe, solar system, the earth, and the ocean. I think I get the basics of BBT from quark soup onward. I'm wondering if there is an explanation for where the quark soup came from? Was it created during inflation? I typically see diagrams of the evolution of the universe that list inflation as a precursor to quark soup.

    My understanding is that the universe has, and continues to expand from what once was a singularity. I realize that what goes on in a 'singularity' is probably beyond what we will ever be able to know. And as far as I understand, it is still an open question as to why the universe began expanding in the first place, why it continues to expand and why that expansion rate looks like it has changed over time. (I know we believe that dark energy is involved but it seems that we still have a lot to learn here.) I understand (vaguely) that matter can be converted into energy and vice verse, and I'm under the impression that the earliest universe was energy dominated (or perhaps only energy?) and then later through interactions like this http://ns.umich.edu/new/releases/8167 matter was created? If the earliest universe was energy dominated, was there a reason for this? (Can only energy exist when things are too hot or too dense? Or perhaps in theory only energy can exist in a singularity since there is no space for matter to occupy?) Was the initial inflationary expansion of the universe necessary for the creation of matter (if matter did not already exist)?

    Beyond this, I think I vaguely understand that as the quark lepton soup cooled, quarks 'combined' to form a proton/neutron plasma. Then after more cooling, hydrogen atoms formed (and some helium and other simple atoms) and at this time light was allowed to travel freely (CMB). Other heavier elements did not form because the universe expanded/cooled too quickly? Over time gravity clumped matter into regions (clusters, galaxies, stars) of high density again and nucleosynthesis occurred to create heavier elements in stars and supernovae. Things continue to evolve into the universe we know today...

    I have a bachelors degree in physics, but it has been a while since I've studied quantum or cosmology and ultimately I'd like to be able to teach this to high schoolers. I'd appreciate any insight this forum can offer!
    Last edited: Apr 8, 2014
  2. jcsd
  3. Apr 8, 2014 #2
    a simple way to look at the quark lepton soup or any other interactions, is the term thermal equilibrium. This is oft described as an ideal gas via an equation of state (Cosmology).

    In essence the universe from 10-43 onward started out at an extremely hot dense state. Due to those conditions any reactions that occur quickly have the reverse reaction and is therefore unstable. As the universe expands particles drop out of thermal equilibrium and can have stable reactions. As particles drop out of equilibrium (freeze out) phase transitions can occur, similar to phase transition of a gas to a liquid though of differing types. The Higg's field is oft treated as a phase transition. Inflation occurs in the earliest moments causing a rapid expansion, at the end of inflation a reheating occurs so once again everything is in thermal equilibrium. However the universe continues to expand due to the cosmological constant so particles will continue to drop out of equilibrium. This is essentially the start of big bang nucleosynthesis. At first the universe is radiation dominant, then there is a radiation-matter equality transition to a matter dominant universe gradually the cosmological constant overcomes the matter dominant universe to become Lambda dominant. No one is clear on when baryo-genesis (change in balance between matter and antimatter) or lepto-genesis occurs other than some time in the earliest moments of the universe and prior to BBN.

    These two articles may also help

    these articles are also handy

    "What we have learned from observational Cosmology"


    "Misconceptions about the big bang"


    my webpage has some historical article that may be of interest

    http://arxiv.org/abs/1302.1498 " “The Waters I am Entering No One yet Has Crossed”: Alexander Friedman and the Origins of Modern Cosmology" written by Ari Belenkiy is one that is also intersting as well as the Great debate

    The "Great debate of the 20's" jubilee reprint article avalable

    hope this helps

    edit: singularity is simply where we no longer understand the processes, not a single infinitely dense point such as a black-hole, also universe is the observable universe only
    Last edited: Apr 8, 2014
  4. Apr 9, 2014 #3
  5. Apr 9, 2014 #4
    Thanks so much for this fantastically informative response Mordred! I have a lot of learning (and re-learning) to do on this topic. It sounds as though a good way to explain this to high schoolers (and myself at the present moment), would be to say that the very early universe was too hot for matter to exist in a stable state. (Please correct me if I'm wrong!)

    Is there a theory that explains why we have the amount of energy/matter in the universe that we do?
    (Apologies if this is explained in the links you have provided- I have some reading to do!)
  6. Apr 9, 2014 #5

    None of the articles I posted cover that answer, there are theories such as a universe from nothing supported by Lawrence R Krauss, cyclic universes or bounce universes. Essentially the hot big bang model makes no statements prior to 10-43 sec. In the universe from nothing quantum virtual particle production could theoretically create a universe from nothing, another variation is one that derived from Allen Guth's false vacuum that a quantum tunneling from a parent universe occurred. Chaotic eternal inflation can create bubble universes in a similar process from small anisotropies. Loop quantum gravity has a bounce process (expanding and collapsing universe).

    However due to limits on our ability to observe the beginning or other universe if such exists all these processes are mathematical conjectures.

    As far as the energy caused by reheating due to inflation that value is calculated in the link


    however no article I have posted covers the pre-inflationary hot dense state origins
  7. Apr 9, 2014 #6
    Thanks! I'm glad I asked. These are all very interesting hypotheses! However, I'm glad you are clear that this is not something that we can currently test with observations. Good to know the limits of our present understanding
    Last edited: Apr 9, 2014
  8. Apr 9, 2014 #7
    From glancing over some of the links you have sent along, perhaps this statement of mine was incorrect? Maybe we do know quite a bit about why and how the universe is expanding (post 10^-43 secs)? I'll get reading...
  9. Apr 9, 2014 #8
    no problem there is a lot of information to grasp in the links and on the cosmology101 webpage I've been developing. By the way I like the article link you posted in regards to particle pair creation from the vacuum
  10. Apr 10, 2014 #9
    No. The Universe is both space-time and the energy it contains. These were created prior to the times which we understand.
    You should really be careful in not over-saturating these kids. They probably could understand that the universe started out as an unimaginably hot, dense, tiny volume and that this volume has been expanding (and energy density declining (NEVER increasing) ever since) Getting into the contributing factors, and the thermodynamics is absurd at the H.S. level. I think you will find it a challenge to simply teach them that the Big Bang was/is not an explosion. Getting into questions about whether space is 4 dimensional (its not, space-time is), and curved? Good luck with that. I think it might be a good bet, since its going to (probably) be such a fruitful area of research during their life-times, to teach them a bit about how important dark matter is (not dark energy, another point I wish you luck with) to the current structure of our galaxy (and how dark matter dominates the galactic mass, and how the visible stuff is in the center of a much larger (halo) structure.
    A bit of why alternatives to cold dark matter are (currently) discounted, could be interesting...trick is to keep it light enough to be palatable. Teaching these kids that the Universe is about 100 billion light years in diameter, that there are four (known) forces, that CMB is light from the BB (and why it is still "just getting here"), that Gen III stars formed before the first galaxies. That black holes don't "suck". That BBN produced only H, He, and a bit of Li and Be. That the opacity of the early universe is because plasmas are opaque and that the Sun's energy production per cubic centimeter is less than that in the human body, that the orbits of the planets is chaotic, and that our "orbit" around Sag A* is more of a meander than a smooth curve. That stars don't really "die".... but I thought this was an oceanography course?
  11. Apr 10, 2014 #10
    abitslow, Thanks! Yes I agree keeping things simple and teaching the history of the universe, solar system, earth, ocean and life in one hour lesson plan is more than daunting.

    I find cosmology/astrophysics/astronomy fascinating so it is difficult for me to not get sucked into learning more and more about these things and to then try to keep the lesson plan concise and clear. I am attempting to take an extremely vast complicated wealth of knowledge and turn it into a short simple logical story, while being careful to point out the major holes in the story where there are still open questions.

    At the moment the story goes something like this:
    -First give some perspective: We are on earth, which is in the solar system, in the Solar Interstellar Neighborhood, in the Milky Way, in the Local Group, in the Virgo Supercluster, within a larger group of local superclusters,... in the observable universe
    -BBT overview: The universe is expanding (and has been expanding from a tiny volume) and becoming overall less dense. The material in the universe is cooling and clumping together (quarks to nucleons, nucleons and electrons to atoms, atoms clump together to form dust and gas, stars and galaxies, etc)
    -Explain where the elements come from: H & He from BBN, and the rest from nucleosynthesis from stars and supernova.
    -Also describe the history and fate of our own sun. Gas/dust cloud collapses to protosun, collapses to star that is burning H to He. Sun gradually warming (will be too hot for us in about a billion years, too hot for liquid water in 3.5 billion years). Becomes a red giant when H fuel in core runs out, collapses again, and starts burning He to C in core, and expands (earth may be engulfed by our sun at this time). Eventually He fuel runs out in core. Sun is then in an unstable state (something about the He that remains in the shell??) Pulses and blows of shell into planetary nebula. Then C core remains as white dwarf
    -The formation of the solar system: Solar Nebular Disk Model- Supernova likely went off nearby that helped initiate formation and contributed heavy elements. Rotating (from supernova turbulence) dust gas cloud turns into a disk as it collapses because of angular momentum - I'll use ice skater analogy. Protosun bulge at the middle turned to sun. Planets accreted in the disk. Terrestrial planets of denser material formed in inner SS, gas giants in outer SS. https://www.physicsforums.com/showthread.php?p=4714874#post4714874 When sun started fusing H to He it emitted a solar wind that "blew away excess" nebular material (including earth's first atmosphere that was mostly made up of lighter elements like H and He)
    -Earth starts out as a relatively homogenous object formed by accretion during formation of the SS. Then partially melts and becomes density stratified (differentiation)
    -young earth undergoes many collisions in its early life including collision with Mars size object whose core combines with early earth's and whose mantle forms debris around the early earth that later will coalesce to form our moon
    -Outgassing (from volcanoes) and impact degassing (vaporizing asteroids/comets) create earth's second atmosphere that includes water vapor.
    -Earth eventually cooled and the salty world ocean gradually accumulated from heavy rains that probably lasted about 20 million years. Explain why liquid water is necessary for life
    -Life forms sometime earlier than ~3.5 billion years ago: Probably in the ocean (likely at hydrothermal vents). How exactly we are not sure, but the building blocks were present (Miller-Urey experiment). show pic of fossil from 3.5 billion years ago
    -Oxygen Revolution: Eventually life evolves to photosynthesize, and this gives us the breathable oxygen that is available in our atmosphere today
    -I may throw in a few facts about how the Earth's climate has changed drastically over its lifetime and why. (I still need to read up on this but it one of the goals of the course is to teach the kids the difference between natural and anthropogenic climate change...)
    -I may also compare the conditions on our planet to other planets to further emphasize the goldilocks criteria and emphasize how crazy (and fragile) it is that we have all the perfect conditions to support life on our planet. (Also need to read up on this too)

    abitslow- You have listed a ton of interesting astronomy tidbits and there are many that I know very little about. If you want to send along more information regarding any of these things, I will gladly read up on it when I have some spare time. In particular, can you point me to a good (beginner friendly) dark matter reference? I don't know much about it.
  12. Apr 10, 2014 #11
    "I may also compare the conditions on our planet to other planets to further emphasize the goldilocks criteria and emphasize how crazy (and fragile) it is that we have all the perfect conditions to support life on our planet. (Also need to read up on this too)"

    Its on the technical side, however has some informative criteria

    Habitable Zones Around Main-Sequence Stars: New Estimates
  13. Apr 10, 2014 #12


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    This seems like an awful lot of backstory for HS students to digest, even ones taking advanced oceanography.
    (Do the ordinary oceanography students get to skip all this and go straight into the watery bits?)

    I think you run the real risk of losing focus in the course.

    Even oceanography in HS at all seems a bit esoteric.
  14. Apr 10, 2014 #13
    Thanks Mordred! I'll have a look into this

    SteamKing - This course is part of a summer program that is supposed to simulate the "college experience". The students live on a college campus, take a class, have access to campus facilities and extracurricular activities of their choosing (art,sports,music,dance,etc). They choose which class they take so these students will hopefully be interested in learning about the ocean. Our course is called "The Ocean and the Environment" and is designed to be an introductory course about ocean science that also highlights humans' relationship with the ocean. I am a physical oceanography graduate student and am co-teaching the class with some fellow grad students in my program. We teach them for 2 and a half hours in the morning and 2 and a half hours in the afternoon for 3 weeks, 5 days a week. We are trying to make the class very interactive (who wants to sit in lecture for 5 hours a day?) and luckily we are located right by the ocean and have access to lots of great resources for hands-on labs and field experiments. We have designed the syllabus ourselves but are loosely following the curriculum outlined in Garrison's book "Oceanography: An Invitation to Marine Science". The first lecture is called "Origins" and covers material similar to what I have listed above. You are right that I may have to cut out the astronomy stuff and skip to the "watery bits" simply because it may be too much to fit into the length of our course... I'm still working this out.
  15. Apr 10, 2014 #14


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    It is widely believed that much of earth's primordial water arrived during the heavy bombardment period in the history of the solar system. Oxygen is readily produced by stars - even 'tiny' stars like our sun. And hydrogen is the most abundant element in the universe. These two atoms have a natural affinity for each other and form strong, stable bonds, making dihydrogen monoxide [water] extremely common in the universe. During photosynthesis, oxygen is liberated from water molecules and released as a waste product into the atmosphere. The hydrogen is converted to sugar and used as food. This is how earth acquired [and replenishes] its oxygen rich atmosphere.
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