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Cool Universe

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  • 21-01-2020 1:18pm
    #1
    Registered Users Posts: 4,497 ✭✭✭


    A quick question.
    After inflation and when the universe cooled enough to allow hydrogen to form, where did that heat dissipate to?
    Did the continued much slower expansion create room for the heat to spread out?


«13

Comments

  • Registered Users Posts: 16,686 ✭✭✭✭Zubeneschamali


    auspicious wrote: »
    A quick question.
    After inflation and when the universe cooled enough to allow hydrogen to form, where did that heat dissipate to?
    Did the continued much slower expansion create room for the heat to spread out?

    Yes, all the way down to the Cosmic Background Radiation at 2.3K


  • Registered Users Posts: 4,497 ✭✭✭auspicious


    I could spend all day asking questions here.
    One more.
    Where is the universe expanding? At the edge? Between galaxies? I.e where is the new space being created?


  • Registered Users Posts: 328 ✭✭mosii


    I believe, at the subatomic particle/ quantum level , every particle is moving in a rotational/angular momentum of some degree,even of plank size dimension.Our knowledge of our solar system,and universe ,tells us every thing is moving in a rotational and angular dimension,of an extremely large measurement.With the advent of Black holes,i believe that these are connections to another superior universe,which is a small or a large part of a multiverse. I think its designed this way ,so as to never have a finite answer ,as to why we exist at all. We dont know where we came from,and we dont know where we are going. I would imagine we are all going back to stardust,but im not sure where our consciousness comes into play in all of this,buy i think it might have a bearing.


  • Registered Users Posts: 16,686 ✭✭✭✭Zubeneschamali


    auspicious wrote: »
    Where is the universe expanding? At the edge? Between galaxies? I.e where is the new space being created?

    It is expanding everywhere, there is no middle and no edge.

    We only see it between us and distant galaxies because it is small and nearby things in our galaxy and other local galaxies are held together against the expansion by gravity.


  • Registered Users Posts: 4,497 ✭✭✭auspicious


    Maybe dark matter is the 'fallout' of this expansion and gravity battle....


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  • Registered Users Posts: 328 ✭✭mosii


    Are we been pushed,or been pulled.We could be inside the connections between universes .Going from one black hole to another.


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    mosii wrote: »
    I believe, at the subatomic particle/ quantum level , every particle is moving in a rotational/angular momentum of some degree
    Particles don't move or have angular momentum at the quantum level.


  • Registered Users Posts: 328 ✭✭mosii


    yes they do


  • Registered Users Posts: 328 ✭✭mosii


    Electrons are not literally spinning balls of charge, but they do have intrinsic angular momentum. Spin angular momentum is real angular momentum


  • Registered Users Posts: 16,686 ✭✭✭✭Zubeneschamali


    mosii wrote: »
    Spin angular momentum is real angular momentum

    It can be modelled as angular momentum, it behaves that way mathematically.

    Does that mean it is real? I don't think so, since electrons are not really little grey charged spinning balls.


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  • Registered Users Posts: 328 ✭✭mosii


    String Theory seems to think the move


  • Registered Users Posts: 328 ✭✭mosii


    String Theory seems to think they move.VIBRATIONS at plank level.


  • Registered Users Posts: 328 ✭✭mosii


    Everything is moving .


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    mosii wrote: »
    yes they do
    They don't. They impart angular momentum into classical objects like our experimental equipment, but it's not a property of the particle itself. This is a consequence of the Kochen Specker theorem.


  • Registered Users Posts: 1,589 ✭✭✭ps200306


    auspicious wrote: »
    After inflation and when the universe cooled enough to allow hydrogen to form, where did that heat dissipate to?
    Did the continued much slower expansion create room for the heat to spread out?
    auspicious wrote: »

    Where is the universe expanding? At the edge? Between galaxies? I.e where is the new space being created?

    The units of the Hubble constant (~70.0 km/sec/Mpc) can give the impression that we are speeding away from the distant galaxies and, by implication, must be speeding toward something else unless more space is injected like air pumped into a balloon.

    I found the idea of a scale factor helpful. It gives more of an idea of a cosmic ruler that grows with time. (Real rulers don't grow with time only because they are prevented from doing so by electromagnetism, just as individual galaxies are prevented by gravity). The Hubble constant falls out of the scale factor -- it's the rate of change of the scale factor divided by its value at any point in time.

    By ignoring the scale factor you can also define a "co-moving" distance between galaxies that doesn't change with time. Galaxies with an unchanging separation are just "going with the flow" (which we've even named the Hubble flow). Any deviation from the Hubble flow has to be caused by gravitational interactions.

    The scale factor also helps answer your first question about heat. We're talking about radiant energy here, in the form of CMB photons. As you might expect, the matter density of the universe is inversely proportional to the cube of the scale factor, as density is inversely proportional to volume. The same is true of the number of CMB photons per unit volume of space. But the changing scale factor also redshifts those photons. So the radiation density of the universe changes inversely with the fourth power of the scale factor -- much quicker than the matter. That's why they talk about the early universe being radiation dominated, and the later universe being matter dominated (i.e. evolution determined by gravity).


  • Registered Users Posts: 328 ✭✭mosii


    String Theory seems to think they move.VIBRATIONS at plank level. Are vibrations movement?


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    mosii wrote: »
    String Theory seems to think they move.VIBRATIONS at plank level. Are vibrations movement?
    First of all String Theory is unproven experimentally.

    Secondly String Theory is a quantum theory as well. So the strings aren't vibrating (nor are they really strings) it's that they impart vibrations (simplifying here) into a classical device.


  • Registered Users Posts: 1,589 ✭✭✭ps200306


    mosii wrote: »
    String Theory seems to think they move.VIBRATIONS at plank level. Are vibrations movement?
    I never got past wave mechanics but I presume the fields in QFT and the strings in String theory are at least somewhat related. I'm guessing the vibrational states of the strings determine properties of particles in a similar sense to how the waves in wave mechanics are quantum probability amplitudes. They are purely mathematical constructs that evolve according to mathematical rules. If they have some ontological connection to the actual particles whose properties they describe, we don't know what it is. It's probably more accurate to say that particles don't exist down at the quantum level. In wave mechanics their trajectories were travelling wave packets -- it's possible for a wave packet to be in motion without the wave going anywhere.


    Wave_packet_%28dispersion%29.gif


  • Registered Users Posts: 328 ✭✭mosii


    String Theory ,,,,In string theory, < I KNOW THEY ARE NOT REAL STRINGS>one of the vibrational states of the string gives rise to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity..Is the graviton not a particle? These things at all levels have got to be moving in some way, albeit in some different state maybe,in my opinion,theory, but i cant prove it . String Theory ,Someday it might be experimentally proven or disproven ,as Richard Feynman said 50 years ago,if it does not agree with experiment,then it is wrong,which is only common sense.


  • Registered Users Posts: 462 ✭✭oriel36


    auspicious wrote: »
    I could spend all day asking questions here.
    One more.
    Where is the universe expanding? At the edge? Between galaxies? I.e where is the new space being created?

    For your own wellbeing I would suggest you stay away from these people as they have no respect for geometry or the Universe. They live in a celestial sphere bubble without knowing nor caring and seem well pleased to dictate to those who know no better counter-productive ideas that no sane person would entertain.

    The background for all motions is space and especially close by in our solar system neighbourhood where we and all the other planets move through space in much the same way as cars move from A to B without considering space as a property even if it does contain solar radiation (light) or the lack of it (night).

    Astronomers, genuine ones, deal with the motions of planets, moons and other objects like comets, asteroids and so on through space and use specific points of reference to account for these motions, the Sun in the case of the planets and the planets in the case of their moons. For instance, we Venus move around the central Sun in much the same manner as we see Jupiter's satellites move around their parent planet -

    https://www.youtube.com/watch?v=FcrBAuLBXag

    http://www.insideastronomy.com/uploads/gallery/album_7/med_gallery_40_7_128459.jpg

    You can even see Jupiter's satellites 'wink out' as they pass behind the planet and into the umbra as a means to appreciate the phases of Venus as they show its fully dark side when it is between our slower planet and the central Sun -

    https://www.youtube.com/watch?v=_7U5VbasKr4&t=95s

    Don't strain your imagination trying to visualize the idea of 'expanding space' as it is a waste of a mind and diminishes genuine astronomy.


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  • Registered Users Posts: 1,589 ✭✭✭ps200306


    oriel36 wrote: »
    For your own wellbeing I would suggest you stay away from these people as they have no respect for geometry or the Universe.

    :D:D:D:D:D

    And for your sanity I suggest you don't entertain oriel36 with an answer, as he will then post the same thing forty times in a row as he has done under different pseudonyms here for years. Let's keep the loonies on their own thread.



    mosii wrote: »
    String Theory ,,,,In string theory, < I KNOW THEY ARE NOT REAL STRINGS>one of the vibrational states of the string gives rise to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity..Is the graviton not a particle? These things at all levels have got to be moving in some way, albeit in some different state maybe,in my opinion,theory, but i cant prove it . String Theory ,Someday it might be experimentally proven or disproven ,as Richard Feynman said 50 years ago,if it does not agree with experiment,then it is wrong,which is only common sense.
    No, it turns out they don't have to be moving in some way. At the quantum level there are only probabilities that a particle will be found at some location. The evolution of the probabilities mirror classical trajectories to some extent on aggregate. Although the particles can also do things that are completely prohibited by classical trajectories. At the quantum level there is nothing you can point out and say "that's a particle moving".


  • Registered Users Posts: 462 ✭✭oriel36


    There are a lot of voodoo merchants setting lower limits such as a 'Planck length', however, when a discussion arose 20 years ago with the mathematician John Baez, he basically disappeared and was not seen again.

    https://groups.google.com/forum/?hl=en#!original/sci.physics/_zO9GpWrWCI/GFH4NEKP1EgJ

    As for Feyman, these people had no respect for astronomy as Roemer proposed his 'equation of light' about 25 years before Newton's empirical doctrine -

    "The Character of Physical Law", and in the pages on Newton's law of
    gravity (pages 22-23) he mentions that observations of the moons of
    jupiter showed that they "were ahead of schedule when Jupiter was
    close to the earth and behind schedule when it was far away, a rather
    odd circumstance. Mr. Roemer [Olaus Roemer, 1644-1710, Danish
    astronomer], having confidence in the Law of Gravitation, came to the
    interesting conclusion that it takes light some time to travel from
    the moons of Jupiter to the earth..." Feynman

    If people like having things made up for them by bluffers and astrophysics is entirely bogus then so well and good, but if they value their perceptive judgments then they will be welcome back to astronomy and the actual history stretching back to remote antiquity.

    If achievement is making these experimental theorists look like dunces then that isn't much of a comfort so better to become familiar with observational astronomy as it was once practiced.


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    mosii wrote: »
    String Theory ,,,,In string theory, < I KNOW THEY ARE NOT REAL STRINGS>one of the vibrational states of the string gives rise to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity..Is the graviton not a particle?
    What I mean is that they are nothing like strings or string-like at all. It's called string theory because certain processes (like quantum tunnelling) in the theory can be approximated well with classical one dimensional objects (i.e. strings).

    If string theory is correct then there is a graviton particle.
    mosii wrote: »
    These things at all levels have got to be moving in some way
    They aren't. You can prove it. They're not moving, they're not stationary. The concept of position or speed or momentum don't apply to them.


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    ps200306 wrote: »
    I never got past wave mechanics but I presume the fields in QFT and the strings in String theory are at least somewhat related.
    Indeed they are. In String Theory the "strings" give rise to quantum "fields". Again though as always these things aren't really strings or fields. For example quantum fields are only so named because in certain experiments they affect devices in a way that is the same as classical fields.
    It's probably more accurate to say that particles don't exist down at the quantum level
    That's provably true in quantum field theory. Particles don't exist except as a certain type of excitation of a certain types of devices (e.g. a Geiger counter)
    No, it turns out they don't have to be moving in some way. At the quantum level there are only probabilities that a particle will be found at some location
    Exactly. Quantum Theory tells you the chance that a quantum object will affect a classical object, like a piece of experimental equipment, at some location (i.e. 40% chance of the device developing a mark in its upper right corner) but it doesn't describe the quantum object itself.


  • Registered Users Posts: 462 ✭✭oriel36


    Fourier wrote: »
    They aren't. You can prove it. They're no moving, they're not stationary. The concept of position or speed or momentum don't apply to them.

    People don't have time for this crap anymore even if it entertains those who want to go down that particularly Victorian rabbit hole.

    https://www.newscientist.com/article/mg20427391-600-alices-adventures-in-algebra-wonderland-solved/

    Astronomy in the 21st century doesn't owe anything to empirical theorists, imaging and time lapse makes it an enjoyable pursuit once more as people grow out of the silly indulgences of clockwork solar system modelers and their Victorian counterparts.


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    oriel36 wrote: »
    People don't have time for this crap anymore even if it entertains those who want to go down that particularly Victorian rabbit hole.

    https://www.newscientist.com/article/mg20427391-600-alices-adventures-in-algebra-wonderland-solved/

    Astronomy in the 21st century doesn't owe anything to empirical theorists, imaging and time lapse makes it an enjoyable pursuit once more as people grow out of the silly indulgences of clockwork solar system modelers and their Victorian counterparts.
    Huh? I wasn't talking about the solar system, I was talking about particles.


  • Registered Users Posts: 462 ✭✭oriel36


    Fourier wrote: »
    Huh? I wasn't talking about the solar system, I was talking about particles.

    Celestial sphere enthusiasts and experimental theorists have their own thing going as I mentioned so many times and it has nothing to do with astronomy, its methods and its insights.

    Carry on, I am sure you will all disappear in a cloud of meaningless voodoo.


  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    oriel36 wrote: »
    Celestial sphere enthusiasts and experimental theorists have their own thing going as I mentioned so many times and it has nothing to do with astronomy
    Yeah but I'm not talking about astronomy.


  • Registered Users Posts: 328 ✭✭mosii


    Are you talking about the wave function?


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  • Registered Users Posts: 10,558 ✭✭✭✭Fourier


    mosii wrote: »
    Are you talking about the wave function?
    The wave function is part of the mathematics of quantum theory, but I wasn't talking about it specifically.

    Just that particles don't have properties like motion or speed or angular momentum.


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