Strange

These can be associated with areas of high star formation. They have little or nothing to do with the creation of stars. As you haven't provided a link (or an extract) here it is: http://arxiv.org/abs/1504.07194 Have you read this paper? You now appear to be randomly searching for anything with the word "star" and "water" and throwing it at the forum. It would be more productive if you actually, you know, discussed the comments other have made and answered some questions.

https://en.wikipedia.org/wiki/List_of_NP-complete_problems

This is described in the paper. (Did you actually read it?) http://scitation.aip.org/content/aip/journal/jcp/143/4/10.1063/1.4922545

Interestingly, the early work on stellar nucleosynthesis was carried out by Fred Hoyle, a strong opponent (and namer) of the big bang theory. Ironic that it is this that proved to be one of the strongest pieces of evidence for the big bang. Can we clarify what you mean by this. By "pre star" do you mean (a) before all stars or (b) before some particular star (e.g. the Sun)? If (a) then the answer is clearly no. if (b) then the answer is yes for second generation (and later) stars.

Gases do not, as far as I know, repel one another. The atoms or molecules in a gas are a certain distance apart because of their constant movement. In the absence of something constraining them (a container or gravity, for example) they will therefore tend to diffuse to fill the available volume. In the case of gasses in space, there is gravity preventing them dispersing completely. And possibly causing their eventual collapse. They may also be ionized, which means there would be electric and magnetic fields affecting their behaviour as well. How do gases behave in deep space? You could start here: https://en.wikipedia.org/wiki/Jeans_instability What does any of this have to do with water, though?

You think gas in space is not affected by gravity? https://en.wikipedia.org/wiki/Jeans_instability

And the evidence for that is? Why not? Gasses on Earth are attracted and compressed by gravity. Why wouldn't the same happen in space? Beliefs with no evidence are not of much value. You had better ask the moderators to move this to the Speculations forum...

No. (Not worded like that, anyway.) It simply says that one twin will experience less elapsed time than the other. No it doesn't. If anything, some people are unhappy with the fact it adds one dimension (time) to the three they are aware of. What do mean? You "get" a value of 9x1016 m2/s2. If you can see it currently, then you are currently seeing it. (That is an nonsensical answer to a nonsensical question.) 14 minutes ago, of course. One, of course. How many do you think exist?

Only if by "reality" you mean that metaphysical realm that is not accessible to human investigation. However, science does investigate the reality that can be observed and measured. In other words, the only reality that can have any effect on us. Yep. Everybody knows that. You might be better off in this long-running thread on another forum where people have been thrashing this out for years: http://cosmoquest.org/forum/showthread.php?153299-The-last-and-final-argument-about-reality (Hope the mods don't mind a link to another forum, but if it gets rid of this pointless discussion ...)

That has nothing to do with water or star formation, which I thought was the subject of the thread. The paper is about the role of oxygen (one of the components of water) in the formation of stars, which I thought was the topic of the thread. Below is an excerpt and the link below to the article from which it came. Yes it does (and it was created in the big bang). Now that really is nothing to do with the thread! They will be at much lower pressures. They will often be ionized. But apart from that, I'm not sure why they would behave significantly differently. What sort of behaviour are you thinking of? (The paper you said isn't relevant is all about the behaviour of gas clouds...)

Well, I thought this was interesting, even if Ant didn't. His questions had me wondering if the first generation of stars were large and short lived just because of the greater density of gas then, or if there were some other reason. It is interesting to see that even minute amounts of other elements can influence the creation and (presumably) evolution of stars.

I'm not sure what you mean. The two events take place at different (4D) coordinates. What do you mean by "no difference"? It doesn't matter if you set the speed of light to 1 (in Plank units) or 3x108 m/s or 2x1012 furlongs/fortnight it is always accounted for in the time it takes for a particle to get from one place to another: it can never do it faster than light, and if it has mass it can never do it at the speed of light. Where do you get the idea that the speed of light is not accounted for? It is fundamental. This is just nonsense. Perhaps if you could get rid of all these weird misconceptions that you keep inventing, you would be able to appreciate the theory and its rather nice description of reality. To put it another way, every one of your objections seems to be: "the theory must be wrong because it says <insert invented nonsense here>."

Was that the sort of information you were looking for or not? Why do you not acknowledge information provided? Why do you answer every question with a question?

They are models. Their accuracy will vary. I don't think they are. Are they? Models are checked against reality (in the process known as "science") but neither our measurements of reality nor the models are perfect, so there are always error bars. (This fact may be omitted in a lot of popularizations of science, which are all about certainty and mythical "proof".) Actually, dark energy is only required to explain the apparent accelerating expansion. But the only reason dark energy is hypothesized is because of measurements of reality. It does not come out of models (although it can be easily added to models as an energy term - hence the name). I think everyone (everyone doing science) knows this.

Is this the sort of thing you are looking for: http://www.nature.com/nature/journal/v425/n6960/abs/nature02071.html So it seems that the creation of heavier elements (particularly carbon and oxygen) by the first stars may be what enabled the smaller stars we see today to form.

I'm not what hasn't been answered... The oxygen in water was formed in stars.

Also, in clouds where stars are forming, any water would presumably be dissociated into hydrogen and oxygen.

I have no idea. I am sure that the first stars (which obviously contained only hydrogen [and a little bit of helium]) were different from later stars (which contained varying proportions of other elements) but this is not a subject I know much about. If you want to know more you could try googling something like stellar metallicity (astronomers refer to all elements formed in stars, i.e. above helium, as "metals").

I get a different answer from both of you! I don't understand how there can be negative values in there ...

Ummm, it implies there is water vapour in those clouds? And ... ?

I have only skimmed through the paper. What about it is interesting / relevant to this thread?

Not really. Pretty much all the lithium on Earth (and elsewhere) was created in stars. The universe is (and was) almost entirely made up of hydrogen and helium. It is, I think, related to the temperature and density in the early universe (and how long those conditions lasted). The relative abundance of hydrogen and helium is one of the bits of evidence that confirms the predictions of the big bang. https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis

From that link: "along with trace amounts of lithium and beryllium". The universe was (and is now) about 92% hydrogen and 8% helium.

The hydrogen in water was created in the big bang. The oxygen was created by supernova explosions of stars. I think there is still some debate about how and when water arrived on Earth. Some of it may have always been there, some may have been introduced by comets crashing into the planet.

What does "actually" get shorter mean? It is an actual, measurable effect. Is that what you mean? No, because when we ask reality it confirms our theories and tells us that there is no universal now. Just looking at the title of this thread again, I don't see any contradiction between the "block universe" view (not a term I like very much, BTW) and your "two nows" concept. Your two "nows" are just two points on a worldline (a null geodesic, in the case of photons) - one is the event where something happens and the other is the event where you see it. The only difference seems to be that you claim that everyone will agree on "when" each of these events occur (both in absolute terms and relative to one another); while relativity theory (and therefore reality) says that the "when" of each event is determined by the choice of coordinates, and that is dependent on things like the relative state of motion of the observers. [edited for clarity ... I hope] Just to add a bit more... What everyone will agree on is the "interval" between the two events (roughly, the 4D distance between the events in space-time). For something that involves light being emitted from a source and seen by you later, this interval is zero.