Question About the Universe

When did you first hear of evolution, and what were the scientifically accepted ages of the earth and the universe at that time? Patterson obtained an age of 455050 million years for the solar system (including the earth) in about 1955, and Sandage obtained an age for the universe of about 14 billion years (within a factor of two) in 1958. Although these ages have been refined since then, they were remarkably close to the modern values. The earth is now thought to be 454020 million years; the oldest material in the solar system is 4568 million years; and the age of the universe is 13.8 billion years. This isn't an exponential increase, so presumably you first heard about evolution before the 1950s.Edited by Astrophile, : I omitted a question about the ages of the earth and the universe that was relevant to Colbard's original post.

Interesting; that was the year before I was born. I won't ask how old you were when you first heard of evolution, but you have certainly had a long time to study it.Fortunately I have some books published in the 1940s that give estimates of the ages of the universe and the earth. One of my astronomy books, 'The size of the universe' by F.J. Hargreaves (published 1948), gives the age of the universe as 'about 2,000,000,000 years'. A geology book, 'Geology in the service of man' by W.G. Fearnsides and O.M.B. Bulman (published 1945), gives the age of the earth as about 2000 million years, thus making the earth and the universe essentially the same age(!).I agree that the scientifically accepted ages have increased since these books were published, but the terrestrial age of 455050 Myr obtained by Patterson and the cosmic age of about 14 billion years (to within a factor of two) obtained by Sandage date from only twelve years after you first heard of evolution, so you can hardly say that these ages have increased exponentially ever since that time.

How do you know this? First, how do you know this? Second, do you personally have an understanding of what these spiritual principles are? If so, what comment can you make on 'the universe, its beginnings, structures etc.' on the basis of these spiritual principles, and can you show how this comment follows from these principles?

I'll discuss this with the trees and other plants in my garden and get back to you. I'm sure you believe this, but I think that you're putting the cart before the horse. I don't see how spiritual principles could exist without a material universe for them to exist in. As for the rest of your post, it is too far from anything that I recognise as science for me to comment on it.

'Tautology' 1. The use of words that merely repeat elements of the meaning already conveyed.
2. (logic) a statement that is always true.
Is this really what you meant to say? No, I didn't, and again I don't understand what you mean or what point you are trying to make. The cosmological principle is the principle that the universe looks much the same to all observers, wherever they are; more technically, it means that the universe is homogeneous and isotropic.

You could add the ages of asteroid families, the rotation of asteroids, and the H-R diagrams of star clusters. The H-R diagrams of globular clusters yield ages of up to 12.7 billion years, and such well-known star clusters as the Hyades and Praesepe are hundreds of millions of years old.

But inflation occurred between 10 to the -36 seconds and 10 to the -32 seconds after the Big Bang, before the formation of protons at 1 microsecond and long before the formation of the first stars about 500 million years after the Big Bang. Inflation has no relevance to the ages of galaxies or stars, or of SN 1987A or any other supernova.

It depends on which stage of star formation you are talking about, but it is from less than 10,000 years for an O-type star with a mass of >20 solar masses, to a few million years for a star like the Sun and >10 million years for an M-type dwarf with a mass of <0.5 solar masses. It's a complex problem, but we have observations of protostars in interstellar clouds, so there is no reasonable doubt that they form there, probably from the small dark clouds called Bok globules. There are many physical processes at work: turbulence in clouds may cause the formation of local density excesses; magnetic fields may play a role, for example in directing mass loss in jets; clouds may cool as a result of molecules emitting infrared and radio radiation. Star clusters form in several generations, and radiation and winds from the first-formed massive stars may compress the smaller condensations in the outer parts of the interstellar cloud and cause them to collapse. We can see this in the Rosette Nebula (NGC 2237-9 and NGC 2244) and the Cone Nebula cluster (NGC 2264) in Monoceros, and in the famous 'Pillars of Creation' image of M16/NGC 6611 in Serpens.To draw an analogy, until fairly recently there was no accepted working model for the generation of electric fields in terrestrial clouds, but we all accepted that lightning is a real phenomenon and that it has a physical cause. Supernovae are real enough; I have seen several myself, in external galaxies. Also, isotopic anomalies in meteorites provide evidence of nearby supernovae that happened a few million years before the formation of the solar system; perhaps these supernovae triggered the collapse of the cloud that formed the Sun and the planets. Triggering of star formation by supernovae is only a more extreme form of the compression of clouds by the radiation and winds of massive OB-type stars, and these massive stars will certainly explode as supernovae at the ends of their lives.Of course, supernovae didn't trigger the formation of the first stars of a cluster, or the first stars in the universe; triggered star formation isn't a universal solution to the problem.I am sorry that I can't answer all your questions, but in my opinion the observational evidence is enough to show that stars form by the formation and collapse of relatively dense condensations in larger interstellar clouds, even if we don't understand everything about the process.

I don't know what sort of evidence you want, and, if I may say so, your post is so ungrammatical that I can barely make out its meaning. The facts are that giant interstellar molecular clouds, with diameters of about 100 light-years and masses up to a million solar masses, exist as observable entities, both in our own Galaxy and in external galaxies; that we observe massive OB stars, with lifetimes of at most a few million years, in these interstellar clouds; that we observe infrared sources (protostars) in Bok globules; that we observe young stars, still surrounded by their accretion discs, associated with interstellar clouds and OB stars; and that the Jeans formula provides a criterion for the mass of a cloud that will collapse under its own gravitation.For example, for a Bok globule consisting of molecular hydrogen with T = 10 K and a number density of 50 billion molecules per cubic metre, a condensation with a mass of 10 to the 30 kg (0.5 solar masses) will contract under its own weight.As I have already said, massive OB stars have lifetimes of only a few million years before they explode as supernovae; the fact that we see protostars and pre-main-sequence stars associated with these OB stars implies that they also are a few million years old. Theoretical calculations yield similar times for the contraction of stars of a few solar masses.The conclusion is that we have observations of stars forming in giant molecular clouds and in active galaxies, and that we have empirical and theoretical evidence for the time-scale of star formation. I have not said anything about star formation in the early universe; the first stars may have been more massive than modern stars, and so would have formed more quickly. However, the redshifts (and therefore the look-back times) of the most distant galaxies suggest that they began to form about 500 million years after the Big Bang.Can you either explain your reasons for rejecting this evidence, or give your own explanation for the detailed facts that I have adduced? Simply saying 'an actual model in physics is non-existent' isn't enough.

You can work it out. The mass of a hydrogen molecule is 3.310 to the -27 kg, so a 0.5 solar mass condensation contains 310 to the 56 molecules. If there are 50 billion molecules per cubic metre, the volume of the condensation is 610 to the 45 cubic metres. If the condensation is spherical, its radius is 1.110 to the 15 metres (1.1 Pm), or about 7500 astronomical units. The free-fall time of this condensation is 510 to the 12 seconds (5 Ts), or about 160,000 years.

7If you look at photographs of the Crab Nebula, the Cygnus Loop and other supernova remnants, you will see that supernovae do disperse their material into interstellar space.

quote:

---

Population III stars were not only smaller than believed, they actually formed in binary systems, that is, pairs of stars that orbit a common center, say the results of a new simulation.

---

Thank-you for this interesting reference.

quote:

---

Very old Population III stars were made essentially of hydrogen and helium. As the stars aged and exploded as supernovae, other elements were formed and these "metals" began showing up in newer stars.

​

"What we have here," said O'Shea, "is a fundamental disconnect between observations and theory, because these really massive stars would have produced a different set of metal abundances than what we see in old stars in our galaxy. If a lot of the Population III stars end up being in binary systems, then overall they would be less massive and so when they inevitably died, the metals they produced would be in much better agreement with what we see observationally."

---

In other words, what your reference is saying is that a model of less massive stars in binary systems yields metal abundances in better agreement with observations than a model of single supermassive stars.The original paper was published in 'Science' (vol. 325, no. 5940, pp. 601-605) on 31 July 2009 as 'The formation of Population III binaries from cosmological initial conditions. According to the abstract,

quote:

---

Previous high-resolution cosmological simulations predicted that the first stars to appear in the early universe were very massive and formed in isolation. Here, we discuss a cosmological simulation in which the central 50 M⊙ (where M⊙ is the mass of the Sun) clump , with one fragment collapsing to densities of grams per cubic centimeter. The second fragment, at a distance of ~800 astronomical units, is also optically thick to its own cooling radiation from molecular hydrogen lines but is still able to cool via collision-induced emission. The two dense peaks will continue to accrete from the surrounding cold gas reservoir over a period of years and will likely form a binary star system.

---

A 50 solar mass clump that breaks up into two cores having a mass ratio of two to one yields two clumps with individual masses of 33 and 16 solar masses. A 16 solar mass star has a life-span of about 15 million years, whereas a 33 solar mass star has a life-span of about 2-3 million years. Both life-spans are much less than the ~400 million years between the Big Bang and the formation of HD 140283, so there would have been plenty of time for these massive binary systems to form and go supernova, dispersing their newly formed metals into space, before HD 140283 was born.

This should have been in 1867, but the last directly observed supernova that I know about was Kepler's supernova in 1604, 410 years ago. Can you tell me more about SN 1867, such as who observed it and which constellation it was in?
I'll try to discuss your other points in another post; it's late, and I ought to be asleep.

A search for 'Population III stars' turned up some interesting information. Observations (R.A.E. Fosbury et al., 2003) of a gravitationally lensed galaxy (z = 3.36) a show anomalous emission-line intensities in the Si III doublet at 188.3 nm and 189.2 nm; this over-abundance of Si may be a nucleosynthetic signature of past pair-instability supernovae in a Population III cluster. T.H. Puzia et al., 2006; (Astrophys. J., 248, 383-388) also find evidence for pair-instability supernovae in the metal abundances of globular clusters in elliptical galaxies. The metal abundances in SDSS J0018-0939 also appear to show the signature of pair-instability supernovae. Kashlinsky et al. (Nature, 2005) attribute the angular power spectrum and amplitude of large-scale fluctuations in the (IR) background to light from the Population III era. One of your own sources said that the distribution of metal abundances in stars is consistent with nucleosynthesis in supernovae with typical masses of 16 to 33 solar masses, and another source says that metal abundances in extremely metal-poor Population II stars implies that their metal-free progenitors had masses of 20-130 solar masses.There have been various hypotheses for the failure to find Population III stars.
Population III stars may have been massive (>1 solar mass), so that all of them have run their course and there are no main-sequence or giant representatives left. They may have accreted metals from the interstellar medium (perhaps even from supernova remnants), or their surface layers may contain ‘metals’ dredged up from the stellar core where they were made. Age estimates from the oldest globular cluster range from 12.6 to 13.4 Gyr. Extremely metal-poor stars, such as HD 140283, SDSS J102915+172927 (Caffau’s star) and SMSS J031300.36-670839.3 have ages of 13 Gyr or more. Studies of white dwarfs show that the Galactic halo is about 11.4 Gyr. The age of the Galactic disc is 8.81.7 Gyr.Let's get to the point. There is compelling evidence that the universe began in a high-density high-temperature state 13.8 Gyr ago, and that hydrogen, helium and lithium were formed in this initial state, about three minutes after time zero. There is also compelling evidence that we can now observe stars that contain small quantities of 'metals' that were formed more than 13 Gyr ago. Nobody has found a way of producing elements heavier than lithium in the 'Big Bang', but these elements are present in the oldest stars that we can see. You say that these 'metals' were not produced in a first generation of metal-free stars. Very well, then; what is your hypothesis for the origin of these 'metals'?