That ignores the rest of the energies listed above, but consider if it were just gravity, yes, it can draw matter to a degree, but I wouldn’t really call 100-10,000 particles per cm^3 to be compressed.
Nature has a funny way of not caring what you would like “to call”. But when we observe reality, we see that it does indeed abide by the math. And as the equation shows, it matters not how sparse (“undense”) a cloud of gas is; clouds of gas in cosmic proportions will succumb to gravity (unless - I suppose such cloud was all racing away from its center-of-mass at escape velocities - I suppose that is a possibility that physicists here could speak to - but even then - to race away from one cloud of matter in the cosmos is to race toward another. You can’t get away from your eventual gravitational clumpages in this cosmic stew.) James (@jammycakes or others) please correct me if my arm-chair astrophysics is also straying off the deep end here.
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I think you’ve made a fair summary of the situation here Mervin. One cubic light year of hydrogen atoms at that density is somewhere between the mass of Jupiter and the mass of the sun.
The one thing I would add is a response to this claim of Patrick’s:
This is simply not true. The Jeans conditions do take into account the different energies such as thermal energy and so on. The fact remains that when you consider the equations, gravity does dominate at larger scales in ways that it does not on much smaller scales.
This is something that Patrick does not appreciate, despite having been told it over and over again. He is appealing to his own intuition of what he expects to happen on scales the size of the Earth or Jupiter, and assuming that his intuition holds on much larger scales of a light year or more. It has been pointed out to him repeatedly, over and over again, that this is simply not the case. 100-10000 particles per cm3 in a laboratory is a very different kettle of fish from 100-10000 particles per cm3 over hundreds of cubic light years.
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True. Gravity is far less useful over such distances.
If the distance between two objects is tripled, the force of gravity is decreased by a factor of 9 .
Yes, but if the size of one of the objects is tripled, the force of gravity is also increased by a factor of twenty-seven.
Patrick, you’re looking at only the parts of the equation that change in the ways that support your argument, while ignoring the ones that don’t. You can’t do that. You have to take into account not just distance and density, but volume as well.
Be careful with your wording there … I think you meant to say that its mass is increased by a factor of 27. It’s gravity would “only” increase by 3 times, given that it’s radius had also tripled. But your point still stands. And Patrick has yet to make any point stand.
[Actually - I take that back, as I think I see what you meant now. Yes - increasing mass by a factor increases its gravity (at some given far away point) by the same straightforward factor. I was just thinking of the surface gravity on the object - which would then be further away.]
Figure 3 shows the believed formation process of a star. But note that in Fig. 3(a) the simulation begins with a dense core, such that gravitational collapse can occur in Fig. 3(b). ‘Something’ is added at the beginning else nothing can happen.
The Jeans’ limit
Without this ‘something’, fundamental physics must necessarily be violated or the Jeans limit must be overcome by either compression of or cooling of the cloud. However, once this limit is overcome, gravity can take over [Fig. 3(b)] and compress the cloud further, to form the protostar [Fig. 3(c)]. But without a mechanism to overcome this natural limitation the cloud would naturally heat up and that would prevent further compression, resulting in equilibrium.
Magnetic fields in the gas cloud are also being investigated. They are no help, but, in fact, an impediment to collapse, unless the cloud can remove the magnetic fields by diffusing away the ions that carry them. The main hope of forming stars is with cooling channels, via infrared radiation from molecular hydrogen, but that requires long periods of time, and thus the simulations start with a mixture of dark matter and hydrogen (normal matter). There is no hope to form stars without the help of the assumed dark matter, no matter (no pun intended) how many hundreds of millions of years you give it. Physics is still the problem.
You neglected to include a link or other attribution.
[Ah, thank you. “Stars don’t form naturally” 
]
This is pertinent, I should think:
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This is interesting, too:
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This is an article by John Hartnett of creation.com insisting that dark matter does not exist.
Here’s an article from Danny Faulkner of Answers in Genesis that insists the exact opposite:
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Political affiliation, conspiracism and evolution denial.
Interaction effect of party and conspiracy mentality on the rejection of human evolution. Simple effects tests with Bonferroni correction (adjusting the cutoff p value to .013) suggest that the effect of conspiracy mentality on rejecting evolution is marginally significant for Republicans ( b = 0.57, p = .018) and for unaffiliated/other ( b = 1.66, p < .001), but it is not significant for Democrats ( b = 0.41, p = .067) or independents ( b = 0.19, p = .350).
‘all the flat Earthers surveyed rejected the existence of anthropogenic climate change (and human evolution)’.
If the radius is tripled, the volume by 4/3pi.r^3 is x 27. If density is constant then the mass, and gravitational field strength at the same distance r from the centre of gravity is too.
g=G.m/r^2
derived from Newton’s law of universal gravitation:
F=G.m1.m2/r^2
where G is 6.67430(15)×10−11 m3⋅kg−1⋅s−2
They don’t as much as they used to. Down 97% from cosmic noon 10ga ago go. In fact the universe has formed 95% of the stars that it ever will.
It’s still happening of course. Here.
That being key, of course. Yes - the math is very straightforward. It would help to distinguish situations, then, to know we are not talking about something like an actually expanding gas cloud (sources, let’s say, from a supernova) where density would decidedly not be constant. But the more general and applicable situation would be for large already existing gas clouds scattered around the cosmos. As weak as gravity certainly is in those situations, it is still by far chief over all the other gas energies that Patrick is trying to invoke at that scale.
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Aye, it’s all here. Refuted irrationally in AiG I’m sure. Which wins hands down of course. We are not primarily a rational creature as we didn’t need to be for 95% of our existence as a species.
You are confusing when Isaiah was first composed with when the copy among the Dead Sea scrolls was penned. The copy dates from over 100 years before Christ at the latest. Yes, the events prophesied are accorded as fulfilled in the NT. But your comment about the NT being written decades after the events does not count against them. In fact, so far as documents from the ancient world are concerned, they are among the closest to the events they record of any we have from that time. The disciples at first preached the gospel in the expectation that christ would return during their lifetime, so they didn’t write down what they’d heard him teach. When they became convinced they were wrong about that, they wrote down what they’d heard him say and seen him do. So what’s the problem?
When you have something theoretical with little to no evidence to prove it one way or the other, then either belief is rational. Sort of.
The fact is that dark matter, like the Oort cloud was created as pixie dust to prop up current theories that otherwise would fall flat with no real evidence of their existence.
Since we (I) can’t seem to agree on whether the maths being used here are actual or theoretical, I will drop out of the star formation debate until I can find better data.
Like I said, I don’t buy it. Solar winds for one.
These winds are characterised by a continuous outflow of material moving at speeds anywhere between 20 and 2,000 km/s.
And why is that? Heat. It’s already too hot, and the equations should be showing that. It takes special cooling and mass to bypass Boyle’s law, among others.
HII and HI regions, smoke and mirrors.