Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: ClaesN on 29/01/2015 17:38:46
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I would like to make a thought experiment and get some help building a universe
out of nothing. What is then, a completely empty space and what are the characteristics?
What do you think about quantum fluctuations in an empty volume? Virtual particles may
be created out of nothing. May, for example, photons be created out of empty space
without disappearing? Have you heard of some experiments made on this?
Suppose we have an infinitely large empty volume described by an ordinary simple
linear coordinate system. We assume further that particles are created by quantum
fluctuations in the whole volume, and they set off in all directions. We follow a photon.
Sooner or later it will bump into other particles, also those created by quantum
fluctuations. We ignore other particles than photons for now and imagine a collision
with another photon. What is happening? I have encountered four different options:
1. They pass through each other?
2. They bounce apart?
3. They merge into something more energetic?
4. They might disappear?
What do you say? Have you heard of experiments that are interesting?
May particles, which directly or indirectly are created by quantum fluctuations, in turn,
form hydrogen? Are there experiments that support such a thesis? Maybe
hydrogen may be formed in quantum fluctuations?
We have an infinitely large volume in which a soup/fluid of elementary particles
of various types are created and travel along with hydrogen. These particles interact
through elastic and inelastic collisions or so-called radiation pressure, strong and weak
nuclear- and electromagnetic forces. May one assume that this fluid contains various
fields with different energy density where the above forces act?
Suppose that two huge hydrogen clouds are formed. Each cloud is held together, but
they are at a distance from each other. How could this have happened on the basis
of the forces mentioned in the previous paragraph? What affects if the clouds are
approaching each other or traveling apart? The distance? The sizes? Energy densities?
How may we apply the gravity- and the cosmological constants in this context?
Is it far-fetched to believe that hydrogen gas clouds can become so large and dense
that stars may be formed? Is it in this context wrong to believe that mass can
accumulate to the extent that black holes are formed? How big can in this case a
black hole become? What happens if it gets too big?
So, is this a start, or shall I pour another glass of wine?
Regards
Claes
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Just about any asymmetry in particle distribution would allow gravity to start forming stars.
The triple point of Hydrogen is 13.8K.
CMBR is about 2.725 K
So, any free hydrogen away from stars would tend to be sticky, and form droplets. Of course, condensation increases temperature, so the process would have to be slow before stars grow large enough to hold themselves together with gravity.
I am, however seeing estimates of higher temperatures as stars initially formed (Around 30K? (http://math.ucr.edu/home/baez/timeline.html#bang)), so perhaps droplets couldn't form????
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Isn't that a rather difficult place to be in? If you mean something void of everything? To measure something you need to be there, and so do whatever instruments you observe by, and if you're there? On the other side, if QM is correct and the way I look at it, its here anyway. It's a symmetry to time.
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Just about any asymmetry in particle distribution would allow gravity to start forming stars.
The triple point of Hydrogen is 13.8K.
CMBR is about 2.725 K
So, any free hydrogen away from stars would tend to be sticky, and form droplets. Of course, condensation increases temperature, so the process would have to be slow before stars grow large enough to hold themselves together with gravity.
I am, however seeing estimates of higher temperatures as stars initially formed (Around 30K? (http://math.ucr.edu/home/baez/timeline.html#bang)), so perhaps droplets couldn't form????
I find it interesting that 10 picoseconds after the big bang it is estimated that the weak force separates into an individual force. This is prior to the QCD phase. The weak force is said to change quark flavor. The latest results mentioned in another thread showed an imbalance in matter and anti-matter decay. This would have to occur within the first 50 microseconds of the universe after the big bang. Is this a feasible timescale for this to happen?
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First thing first.
How a hydrogen is formed? A electron attracted by a proton, quantum dance around proton to form hydrogen atom?
Is the electron moving or not? If not it will fall in. If it moves where the energy from?
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Just about any asymmetry in particle distribution would allow gravity to start forming stars.
The triple point of Hydrogen is 13.8K.
CMBR is about 2.725 K
So, any free hydrogen away from stars would tend to be sticky, and form droplets. Of course, condensation increases temperature, so the process would have to be slow before stars grow large enough to hold themselves together with gravity.
I am, however seeing estimates of higher temperatures as stars initially formed (Around 30K? (http://math.ucr.edu/home/baez/timeline.html#bang)), so perhaps droplets couldn't form????
In this thought experiment radiation from any big bang is not around. But maybe the quantum fluctuations of photons would be isotropic black body radiation giving a temperature at 2.725 K? Anyway, I guess droplets wouldn’t form...Hm?
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Isn't that a rather difficult place to be in? If you mean something void of everything? To measure something you need to be there, and so do whatever instruments you observe by, and if you're there? On the other side, if QM is correct and the way I look at it, its here anyway. It's a symmetry to time.
I agree with you, but could you describe more what you mean by "It's a symmetry to time" in accordance with the thought experiment?
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Just about any asymmetry in particle distribution would allow gravity to start forming stars.
The triple point of Hydrogen is 13.8K.
CMBR is about 2.725 K
So, any free hydrogen away from stars would tend to be sticky, and form droplets. Of course, condensation increases temperature, so the process would have to be slow before stars grow large enough to hold themselves together with gravity.
I am, however seeing estimates of higher temperatures as stars initially formed (Around 30K? (http://math.ucr.edu/home/baez/timeline.html#bang)), so perhaps droplets couldn't form????
When considering the phase of a substance, one must account for both the temperature and pressure! Liquid hydrogen exists at room temperature when highly compressed, similarly water can be gaseous at extremely low temperatures, given sufficiently low pressure. Hydrogen does not need to liquify for a star to form. The gravity of a huge cloud of hydrogen should be enough to collapse it (slowly) to the point where it is gravitationally bound together into a single mass (gas, liquid, solid, plasma or mixtures thereof depending on other parameters)
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First thing first.
How a hydrogen is formed? A electron attracted by a proton, quantum dance around proton to form hydrogen atom?
Is the electron moving or not? If not it will fall in. If it moves where the energy from?
jccc, please stop bringing this question up in every thread! You have asked it so many times, and gotten the same answer every time. Pete may have been the first to lose patience with it, but I think it is testing the limits of everyone on the forum. Either accept that there is an understood answer, and start learning why it makes sense, or drop it. Please? There are plenty of interesting threads on the forum that don't need to be hijacked by the inane bickering that is sure to come out of this discussion.
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First thing first.
How a hydrogen is formed? A electron attracted by a proton, quantum dance around proton to form hydrogen atom?
Is the electron moving or not? If not it will fall in. If it moves where the energy from?
jccc, please stop bringing this question up in every thread! You have asked it so many times, and gotten the same answer every time. Pete may have been the first to lose patience with it, but I think it is testing the limits of everyone on the forum. Either accept that there is an understood answer, and start learning why it makes sense, or drop it. Please? There are plenty of interesting threads on the forum that don't need to be hijacked by the inane bickering that is sure to come out of this discussion.
Sounds like a low blow, pilot.
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I just want to build one hydrogen atom. I have an electron and a proton.
Any QM expert can teach me how to build the atom?
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I just want to build one hydrogen atom. I have an electron and a proton.
Any QM expert can teach me how to build the atom?
There are many examples of protons and electrons combining to make stable atoms.
Alpha Decay is the ejection of a Helium nucleus from a heavier atom, which is the source of most of our underground stocks of Helium on Earth.
Beta Decay is the ejection of a proton from a heavier atom, and picks up an electron somewhere to form a stable atom.
We have electric arc welding, or lightening that creates ions and plasma without throwing the planet off kilter.
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I just want to build one hydrogen atom. I have an electron and a proton.
Any QM expert can teach me how to build the atom?
No matter how far away, the electron and the proton are attracting each other all the time. - correct to me.
In free space, they accelerating to each other, faster and faster, till close enough, QM effects come to play, form an atom. - confuse me.
My theory, proton is protected by a ball of negative charged space fluid. Electron float within that fluid at atom radius.
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Beta Decay is the ejection of a proton from a heavier atom, and picks up an electron somewhere to form a stable atom.
Beta decay is ejection of an electron (β–) or positron (β+) from a heavier atom...
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Beta Decay is the ejection of a proton from a heavier atom, and picks up an electron somewhere to form a stable atom.
Beta decay is ejection of an electron (β–) or positron (β+) from a heavier atom...
Picking bones? Anyone can read and typo.
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Beta Decay is the ejection of a proton from a heavier atom, and picks up an electron somewhere to form a stable atom.
Beta decay is ejection of an electron (β–) or positron (β+) from a heavier atom...
Picking bones? Anyone can read and typo.
Yes, probably a simple mistake, but not a typo. I didn't want the error to stand uncorrected, especially since CliffordK continued to elaborate on the mistake...
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Thought you guys are on the same side. Inside.
Aren't we all?
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Sorry.. you're right.
Beta is electrons and positrons. They still recombine with other particles to form neutral atoms.
I should know better... [xx(]
Proton Emission (http://en.wikipedia.org/wiki/Proton_emission) does occur, but is apparently rare.
Neutron Emission (http://en.wikipedia.org/wiki/Neutron_emission) is more common. Free neutrons (http://en.wikipedia.org/wiki/Neutron#Free_neutron_decay) apparently do exist with a half-life of about 10 minutes before undergoing Beta Decay into a proton + electron.
Occasionally as Neutrons decay into Protons + Electrons, Bound State Beta Decay (http://en.wikipedia.org/wiki/Beta_decay#Bound-state_.CE.B2.E2.88.92_decay) will occur in which an intact Hydrogen atom forms.
Anyway, there are many natural examples of ions, plasmas, and bare protons picking up or loosing electrons so that assuming the proto-universe was electronically neutral, the recombining of elementary particles would not be unexpected. Or, if some of the elementary particles were free neutrons, they would have essentially decayed forming hydrogen atoms.
I suppose one question is whether electrons and protons were released into the proto-universe at the same velocity. If there was a point source with a big velocity differential, then there could be a problem.
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At the big bang it all depends upon how the forces separated out and how the relative strengths interacted during this separation. There is a reason why masses differ yet the charges are equal and opposite. Everything balances in the end. So velocities may be irrelevant and not easily described in such a situation. Then you have an intense dilation of time which will also be a function of mass and this delicate balance..