Why the universe has to be so big?

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Saint, Oct 29, 2017.

  1. Gawdzilla Sama Registered Senior Member

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    Lucifer would be angry with you.
     
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  3. Michael 345 Valued Senior Member

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    What about cherubs?

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  5. paddoboy Valued Senior Member

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    Making more accusations re the mods again? Sheesh, not a very happy little vegemite are we. Or is this simply vanity on your part?
    No you have pulled the wrong rein again qreeus. As I have said many times, the uncountable content and extent of the universe, plus the stuff of life being everywhere, is logical reason to believe we are probably not alone. And although we as yet do not have any evidence of ETL, and especially evidence for any Alien visitations, still most reputable scientists accept that it is likely that we are not alone. Of course time and distance are the two great barriers to any contact. If by the slimmest chance that we were alone, it would raise far many more questions then the affirmative, and the god botherers and IDers would have a field day.
    The answer I gave, noting of course river's leanings to ghosts, goblins, Alien UFOs, and pseudoscience was amply sufficient.
    Matter/energy are neither created nor destroyed, but simply changes state from one to the other. The Steady State hypothetical has long ago been debunked.
     
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  7. paddoboy Valued Senior Member

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    Yes most reputable scientists without any agenda agree with that.
    While that is certainly possible, it would raise far many more questions and the IDers would have a field day!
     
  8. Q-reeus Valued Senior Member

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    Does this mean at last you have actually decided to climb down from the fence and definitely side with the Krauss, Gibbs etc camp? Therefore repudiating those earlier postings endorsing the Carroll etc. camp that maintains overall energy is not conserved? Sure looks like it. But just plainly say yes or no. I won't even press for a competent argument to justify that position.
     
  9. paddoboy Valued Senior Member

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    I'm actually not interested in what any self interested, conceited, agenda driven individual thinks or believes, or says or feels. Sorry about that.
     
  10. Q-reeus Valued Senior Member

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    Not exactly a straight yes or no answer. What's the problem with just making a definite stand?
     
  11. paddoboy Valued Senior Member

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    Here's an interesting paper for those approaching this thread genuinely.....

    https://arxiv.org/ftp/arxiv/papers/0810/0810.1629.pdf

    Does the universe obey the energy conservation law by a constant mass or an increasing mass with radius during its evolution?

    Abstract :

    How the energy conservation law is obeyed by the universe during its evolution is an important but not yet unanimously resolved question. Does the universe have a constant mass during its evolution or has its mass been increasing with its radius? Here, we evaluate the two contending propositions within the context of the Friedmann equations and the standard big bang theory. We find that though both propositions appeal to the Friedmann equations for validity, an increasing mass with increasing radius is more in harmony with the thermal history of the big bang model. In addition, temperature and flatness problems that plague the constant mass proposal are mitigated by the increasing mass with radius proposal. We conclude that the universe has been increasing in mass and radius in obedience to the energy conservation law.

    Concluding remarks

    The knowledge that the mass of the universe now seems to be a mixture of radiation, matter and dark matter forms has become fairly established. But the exact way the universe obeys the energy conservation law remains fundamental to our understanding of cosmic evolution. Has all that mass always been there, the proportion of the various forms depending on the prevailing temperature that permits their stability? Or does additional mass appear with increasing radius, taking the form dictated by the energy densities and ambient temperatures prevailing at its appearance? The psychological barrier, where additional mass can come from, especially when considered alongside the law of conservation of mass, must undoubtedly have played a significant role in the speculations leading to the constant mass hypothesis. Alternative ideas of creation from nothing which later emerged have however become increasingly popular. Despite remaining hesitations about where additional mass could be coming from, on the overall balance of consistency, we conclude that the energy conservation law is better obeyed by means of increasing mass of the universe with its radius. The bases for our conclusion include compatibility with the Friedmann equations with fewer assumptions and improvisation, better harmony with the thermal features of the standard big bang model and the mitigation of the temperature and flatness problems which characterize the constant mass proposal. The findings here are obtained almost entirely within the context of General relativity, which has a wide acceptance in the scientific community. However, not too different conclusions can be described outside GR, as for example based on the behaviour of a primeval photon fluctuating from nothing.
     
  12. Q-reeus Valued Senior Member

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    That article grabbed no doubt owing to the title alone, is poorly written and poorly argued. Sean Carroll would eat that gent alive.
    Got a chuckle out of for instance:
    "The energy conservation law can therefore be expressed by stating that the total energy of the universe is the sum of the positive energy of matter and the negative energy of the radius and it is a conserved quantity." (bottom of p7 into top of p8)
    Negative energy of 'the radius'? Ha ha - good one Prof/Dr Ojo. Well at least it doesn't quite qualify as a Nigerian scam.
    But no sweat - I'm expecting this to be handled by a steady cut&paste deluge of further articles - all with nice titles.
     
  13. paddoboy Valued Senior Member

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    Well as facts stand, it's your own take on many things that just fall short of a Nigerian scam.
    We conclude that the universe has been increasing in mass and radius in obedience to the energy conservation law.
     
  14. Q-reeus Valued Senior Member

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    I will take that cut&paste bolded sentence to be your definitive stand. Hence you are now in effect siding with the Krauss et. al. camp over that of Carroll et.al. camp. So be it.
    A word search of that article failed to find any mention of Noether's theorem - and it's breakdown in GR. No real surprise. Here's a much better argued piece by Lubos Motl you just might have enough grey matter to gain from: https://motls.blogspot.com/2010/08/why-and-how-energy-is-not-conserved-in.html
     
  15. paddoboy Valued Senior Member

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  16. paddoboy Valued Senior Member

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    https://www.scientificamerican.com/article/energy-can-neither-be-created-nor-destroyed/

    The conservation of energy is an absolute law, and yet it seems to fly in the face of things we observe every day. Sparks create a fire, which generates heat—manifest energy that wasn’t there before. A battery produces power. A nuclear bomb creates an explosion. Each of these situations, however, is simply a case of energy changing form. Even the seemingly paradoxical dark energy causing the universe’s expansion to accelerate, we will see, obeys this rule.

    The law of conservation of energy, also known as the first law of thermodynamics, states that the energy of a closed system must remain constant—it can neither increase nor decrease without interference from outside. The universe itself is a closed system, so the total amount of energy in existence has always been the same. The forms that energy takes, however, are constantly changing.

    Potential and kinetic energy are two of the most basic forms, familiar from high school physics class: Gravitational potential is the stored energy of a boulder pushed up a hill, poised to roll down. Kinetic energy is the energy of its motion when it starts rolling. The sum of these is called mechanical energy. The heat in a hot object is the mechanical energy of its atoms and molecules in motion. In the 19th century physicists realized that the heat produced by a moving machine was the machine’s gross mechanical energy converted into the microscopic mechanical energy of atoms. Chemical energy is another form of potential energy stored in molecular chemical bonds. It is this energy, stockpiled in your bodily cells, that allows you to run and jump. Other forms of energy include electromagnetic energy, or light, and nuclear energy—the potential energy of the nuclear forces in atoms. There are many more. Even mass is a form of energy, as Albert Einstein’s famous E = mc2 showed.

    Fire is a conversion of chemical energy into thermal and electromagnetic energy via a chemical reaction that combines the molecules in fuel (wood, say) with oxygen from the air to create water and carbon dioxide. It releases energy in the form of heat and light. A battery converts chemical energy into electrical energy. A nuclear bomb converts nuclear energy into thermal, electromagnetic and kinetic energy.

    As scientists have better understood the forms of energy, they have revealed new ways for energy to convert from one form to another. When physicists first formulated quantum theorythey realized that an electron in an atom can jump from one energy level to another, giving off or absorbing light. In 1924 Niels Bohr, Hans Kramers, and John Slater proposed that these quantum jumps temporarily violated energy conservation. According to the physicists, each quantum jump would liberate or absorb energy, and only on average would energy be conserved.

    Einstein objected fervently to the idea that quantum mechanics defied energy conservation. And it turns out he was right. After physicists refined quantum mechanics a few years later, scientists understood that although the energy of each electron might fluctuate in a probabilistic haze, the total energy of the electron and its radiation remained constant at every moment of the process. Energy was conserved.

    Modern cosmology has offered up new riddles in energy conservation. We now know that the universe is expanding at a faster and faster rate—propelled by something scientists call dark energy. This is thought to be the intrinsic energy per cubic centimeter of empty space. But if the universe is a closed system with a finite amount of energy, how can it spawn more empty space, which must contain more intrinsic energy, without creating additional energy?

    It turns out that in Einstein’s theory of general relativity, regions of space with positive energy actually push space outward. As space expands, it releases stored up gravitational potential energy, which converts into the intrinsic energy that fills the newly created volume. So even the expansion of the universe is controlled by the law of energy conservation.
    https://www.scientificamerican.com/article/energy-can-neither-be-created-nor-destroyed/
     
  17. Q-reeus Valued Senior Member

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    As expected - handled by a cut&paste campaign. That engaging puff piece by Clara Moskowitz amounts to no more than an opinion. Try actually studying the article by Motl.
     
  18. paddoboy Valued Senior Member

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    Her opinion certainly makes more sense then yours....

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  19. paddoboy Valued Senior Member

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    I must agree with you as far as Angels go anyway. Here is a real dinky di Greek Angel.

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  20. Saint Valued Senior Member

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    the school's Science teacher told my kids that the nature exists by itself, and lives just sprung out spontaneously.
     
  21. paddoboy Valued Senior Member

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    I would imagine he probably told them correctly, that nature, (the universe) exists independent of us, and that life is a simple chemical process that arose....or words to that effect
     
  22. paddoboy Valued Senior Member

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    I was informed once by a young GR expert that WHs were actually impossible to exist: The reasons I have forgotten at this time as it was more then a decade ago, probably closer to two decades.. But as long as one understands the speculative nature of that hypothetical, it was also a favourite of mine.
     
  23. spidergoat Valued Senior Member

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    True.
     

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