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BS: One for the astrophysicist
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Subject: BS: One for the astrophysicist From: SPB-Cooperator Date: 28 Jul 15 - 01:07 PM Did the galaxies form stars or did the stars form galaxies? |
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Subject: RE: BS: One for the astrophysicist From: GUEST Date: 28 Jul 15 - 01:24 PM Yes. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,pete from seven stars link Date: 28 Jul 15 - 01:28 PM this should be interesting..... |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 28 Jul 15 - 01:32 PM Just have pete check with God & then give us the straight dope. Easy. |
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Subject: RE: BS: One for the astrophysicist From: Will Fly Date: 28 Jul 15 - 01:47 PM The universe is composed of at least a billion galaxies, and each galaxy contains billions of stars. |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 28 Jul 15 - 01:49 PM And all of 'em only 10,000 years old. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 02:04 PM Well didn't Stars form first so galaxies followed you/I would guess.My belief is consciousness came first which in turn formed everything.Just not consciousness as we humans currently understand it. |
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Subject: RE: BS: One for the astrophysicist From: Jack Blandiver Date: 28 Jul 15 - 03:08 PM And all of 'em only 10,000 years old I thought it was 6,000? Even the ones in Hubble's Extreme Deep Field image which reveals galaxies that span back 13.2 billion years in time. Go figure. |
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Subject: RE: BS: One for the astrophysicist From: Fergie Date: 28 Jul 15 - 03:12 PM Guest Time stamp: What evidence can you provide for your assertion that "consciousness came first which in turned formed everything"? |
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Subject: RE: BS: One for the astrophysicist From: Jack Blandiver Date: 28 Jul 15 - 03:21 PM I think consciousness is euphemism for God. I prefer my universe utterly devoid of man-made concepts like consciousness or divinity so we can marvel at things like GRAVITY which is so much more amazing than make believe. And they're still figuring it out. |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 28 Jul 15 - 03:44 PM I thought it was 6,000? I was allowing God a margin of error. |
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Subject: RE: BS: One for the astrophysicist From: Jack Blandiver Date: 28 Jul 15 - 04:01 PM Error? Heaven forfend! The date of Creation is October 23, 4004 BC. Four years older than Newton believed, seemingly... Read all about it on WIKI. |
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Subject: Lyr Add: EVERYBODY (John Prine) From: GUEST Date: 28 Jul 15 - 04:08 PM EVERYBODY Written by John Prine As recorded by John Prine on “Diamonds in the Rough” (1972)
1. While out sailing on the ocean, while out sailing on the sea,
CHORUS: “Everybody needs somebody that they can talk to,
2. Well, he spoke to me of morality, starvation, pain, and sin.
3. Now, we sat there for an hour or two, just a-eatin' that gospel pie, |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 04:24 PM Hi Fergie, remember I wrote my belief. Either later on today or soon when I have more time, I will try and explain why I lean towards what I said.Been a while since I gave it serious thinking so need time to express it cohesively.I am open to be educated if persuaded otherwise. @Jack--" " -I think consciousness is euphemism for God. I prefer my universe utterly devoid of man-made concepts like consciousness or divinity so we can marvel at things like GRAVITY which is so much more amazing than make believe. And they're still figuring it out." " I'm usually in agreement with the majority of what you post Jack,but can we keep personal notions of God out of it, or it will go tits up. Trying to define "God" gets fekin tedious quick. 8) |
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Subject: RE: BS: One for the astrophysicist From: Bill D Date: 28 Jul 15 - 05:17 PM current general opinion " The "top-down" model on the origin of the galaxies says that they formed from huge gas clouds larger than the resulting galaxy. The clouds began collapsing because their internal gravity was strong enough to overcome the pressure in the cloud. If the gas cloud was slowly rotating, then the collapsing gas cloud formed most of its stars before the cloud could flatten into a disk. The result was an elliptical galaxy. If the gas cloud was rotating faster, then the collapsing gas cloud formed a disk before most of the stars were made. The result was a spiral galaxy." Thus, 'most', if not all, stars were created after the basic galaxies assumed their shapes. (I have watched 5-6 TV programs which say as much,) |
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Subject: RE: BS: One for the astrophysicist From: GUEST,henryetta Date: 28 Jul 15 - 05:31 PM "Did the galaxies form stars or did the stars form galaxies?" I think the stars formed galaxies. As soon as you have two stars, they exert a gravitational pull on one another, and that's going to lead to galaxy formation, when there are enough stars. But before you have two stars, you have one star, and that one star is the beginning was the predecessor of the galaxies. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 05:42 PM Just a quickie, as finding it hard to get quiet time at mo due to busy house. So Bill do we call these areas of overdensities galaxies,or do they become galaxies once stars and matter are pulled into them.You have me thinking now. |
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Subject: RE: BS: One for the astrophysicist From: DMcG Date: 28 Jul 15 - 05:50 PM you need to know what a galaxy is first |
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Subject: RE: BS: One for the astrophysicist From: Rumncoke Date: 28 Jul 15 - 06:30 PM I think - so far, no one has managed to work out just what is going on, and how we got from the start to where we are now - the numbers are wrong for how the universe is unfolding. I have to confess to a certain wicked satisfaction over this difficulty. When the galaxies are studied, quantified and their velocity and acceleration calculated insufficient mass is visible to account for the way they move. Basically, they aren't shiny enough. \I think that galaxies have to have formed first. At the start, everywhere and everything was all in the same place, and then there was light. At first there wasn't light because there was nowhere for it to be, or do its thing. Nothing could happen because there was nowhere for anything to happen, so probably time could not go either. Then - bang - as they say, and everything was up and running away from everything else, and matter separated into smaller bits and gravity began to make the spaces between the bits larger, so there were galaxies, and then began the great dance where there was movement and meetings, and the term orbit became interesting. |
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Subject: RE: BS: One for the astrophysicist From: Keith A of Hertford Date: 28 Jul 15 - 06:40 PM There is very little matter between the galaxies. The galaxies are clumps of matter within and from which stars formed. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 06:57 PM Read this Keith,as you sound so sure with your opinion,apologies if I'm reading you wrong. http://science.nasa.gov/astrophysics/focus-areas/what-are-galaxies/ " "the Universe was composed of radiation and subatomic particles. What happened next is up for debate - did small particles slowly team up and gradually form stars, star clusters, and eventually galaxies? Or did the Universe first organize as immense clumps of matter that later subdivided into galaxies? " " As DMcG stated above we need to define Galaxy. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 07:47 PM If we just go by the dictionary definition. " galaxy ˈɡaləksi/ noun: galaxy; plural noun: galaxies a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction. synonyms: star system, solar system, constellation, cluster," --------- What has to be present for something to be called a galaxy ? would be a simplistic way of answering the OP. |
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Subject: RE: BS: One for the astrophysicist From: GUEST Date: 28 Jul 15 - 08:09 PM A Galaxy. |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 28 Jul 15 - 08:20 PM Read this Keith,as you sound so sure with your opinion Always is. Knows everything, and knows nowt. |
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Subject: RE: BS: One for the astrophysicist From: Ed T Date: 28 Jul 15 - 08:29 PM "The universe may have existed forever, according to a new model that applies quantum correction terms to complement Einstein's theory of general relativity. The model may also account for dark matter and dark energy, resolving multiple problems at once." Read more at: http://phys.org/news/2015-02-big-quantum-equation-universe.html#jCp no beginning, no end? |
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Subject: RE: BS: One for the astrophysicist From: Bill D Date: 28 Jul 15 - 08:36 PM The question of how dense & organized a 'clump' must be to be called a galaxy is not the crucial thing. It's like debating whether Pluto should be called a 'planet' or not. There seems to be two possible directions a clump might take as stars begin to form, as described in the link, but no experts seem to think that stars just developed in some lonely isolation, then 'got together'. What is important to understanding the universe is how they formed and what particles were involved and where all the matter that seems to to be mathematically required, but is not evident, might "be". And Henrietta, "I think the stars formed galaxies. As soon as you have two stars, they exert a gravitational pull on one another..."... it just don't work that way. That's the kind of 'rational guessing' that people did before we had all the data of the last 20-30 years. Particles have a small, but significant 'gravity', and they needed to coalesce into large clumpy areas BEFORE they formed the smaller clumps that became stars. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 09:48 PM Bill Some stars do form in isolation,and stars do gravitate to one another,but I understand what your saying.Black holes exert influence too as does the universes accelerating expansion. I'm starting to get out my depth here, but couldn't the missing matter be stars and black holes consuming their mass. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,HiLo Date: 28 Jul 15 - 09:48 PM Greg. It might help the general atmosphere here if you treated this forum and those of us who enjoy it with a little bit of respect. It is not a lot to ask, it is how decent people behave toward each other. If there are a lot of galaxies, what is between them or are galaxies connected ? |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 28 Jul 15 - 09:49 PM You're...8) |
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Subject: RE: BS: One for the astrophysicist From: Rob Naylor Date: 28 Jul 15 - 10:45 PM Quite a lot is up for debate about exactly how early galaxies formed, but there is no debate about the fact that stars are still forming within galaxies. The "original" stars that formed are mostly designated "Population II". Population II stars tend to be older, and to contain a much smaller percentage of heavy elements than Population I. Often found in galactic nuclei and globular clusters. Population I stars are younger, and usually richer in heavy elements. The consensus is that they formed from the debris left over from nova and supernova explosions of Population II stars, which would have, by the time they went nova, have fused a fair percentage of their original hydrogen content into heavier elements. They're still being formed now...we can observe this in certain nebulae. They tend to be found in the spiral arms or outer areas of galaxies, and it's likely that they're the only stars that would be able to support the formation of rocky planets. |
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Subject: RE: BS: One for the astrophysicist From: Rob Naylor Date: 28 Jul 15 - 11:00 PM Ed T: I think the "new model" is described in that link in a very simplistic way. The comment that it dispenses with the possibility of a "big crunch" is unnecessary, as the current models indicate that the universe is neither "open" nor "closed" but "flat". This short clip goes into that at a layperson's level: Laurence Krause Lecture Extract It also answers to some extent HiLo's question about "what is between galaxies?". To elaborate a bit, galaxies tend to occur in clusters, and there is nothing much visible between these clusters. In fact, even within clusters, most galaxies are widely separated. But then we get into discussions on dark matter and dark energy..... |
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Subject: RE: BS: One for the astrophysicist From: Rob Naylor Date: 28 Jul 15 - 11:15 PM Interestingly, one of the guys I was at university with was involved in the antarctic and other balloon flights that produced the data Krause is referencing in that clip. I do geodesy and geophysics now, but my first degree was in astrophysics, and I still take an interest in it when I have time. IMO it's well worth looking at Lawrence (mis-spelled it above)Krause's full "Universe From Nothing" lecture if you have an interest in the subject: Full Krause UFN Lecture And also reading his book of the same title, which is one of the most "understandable by the lay person" books on cosmology I've ever come across. |
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Subject: RE: BS: One for the astrophysicist From: Rob Naylor Date: 28 Jul 15 - 11:31 PM I'm surely struggling with the correct spelling of LAWRENCE KRAUSS's name today! Been in Russia too long. Home next week, at last. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Grishka Date: 29 Jul 15 - 07:25 AM The word "form" is ambiguous. A question precise enough for science may be: "Whenever a star is initiated, does it belong to a clearly defined galaxy system until it ceases to radiate?" Answer from the above experts: not necessarily. We should be very careful with the word "cause" and related notions such as "A formed B". They are not properties of reality, but of concepts of reality. |
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Subject: RE: BS: One for the astrophysicist From: Rapparee Date: 29 Jul 15 - 10:16 AM What's being discussed here can't be stated accurately in anything but the language of mathematics. However, physicists toss out a hypothesis and see it shot down by peer review (that's the way it's supposed to work). Then, based upon the rubble of previous thought*, new data suggests new approaches and things. Me, I don't know yet. I would very much like to go out there and poke around and find out. *Not all "old thought" is wrong. Newton's gravitation works well in the macro universe but fails in the quantum physics. Izzy was right and wrong; physicists, at least the good ones, recognize that. |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 29 Jul 15 - 10:52 AM Greg. It might help the general atmosphere here if you treated this forum and those of us who enjoy it with a little bit of respect. Will take it under advisement, Hi, just so soon as certain individuals give facts a little bit of respect. |
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Subject: RE: BS: One for the astrophysicist From: GUEST Date: 29 Jul 15 - 11:42 AM Mudcat Quantum Entanglement-one adversary posts, somewhere, causing a related reaction by a nemesis. While it may make a lot of theoretical sense to those involved, the logic escapes those not so engaged. Unfortunately, if you take a peek, or even don't look, the action-reaction action does not go away, trancending the expanse of the mudcat universe. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,HiLo Date: 29 Jul 15 - 12:25 PM Your obsession with Keith is childish and tedious. He does provide facts. I was just hoping you would be respectful of all those who post. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,henryetta Date: 29 Jul 15 - 12:58 PM Guest, thanks for the beautiful image. It certainly opens doors to new definitions of a galaxy. Bill D, look at the big picture. I may have missed the details about sub-atomic particles, buy my post stopped the silly people who want to sneer about Bishop Ussher and brought in people who actually wish to discuss the universe. Rob, whatcha been doing in Russia? |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Time stamp Date: 29 Jul 15 - 05:00 PM @Fegie. Can't think of a way of getting into what you asked without taking the thread way off course.Tried it before in an appropriate thread but nobody could/would engage,as there is loads to consider and it is a minefield. I suppose I can say this though.There is a very large group of people who have experienced something regarding consciousness/awareness that they want science to address.This experience gives a perspective that reveals something about existence, they think, and my thinking heavily leans that way too. Here is a clip of someone trying to convey it. https://www.youtube.com/watch?v=ZV5Vptx0iJw Apologies and carry on.8) |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 29 Jul 15 - 05:24 PM Your obsession with Keith Not so - there are others. Keith may occasionally present facts- usually ones irrelevant to the point at issue- but still has no respect for those that do not support his preconcieved notions. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Pete from seven stars link Date: 29 Jul 15 - 05:42 PM I should have thought that the only way you could conjecture a universe from nothing, is to change the definition of nothing. And I see that one of the earliest comments on the Krause video makes exactly that point. Can anyone point to Greg posting anything constructive ? Put downs and mockery are not constructive ! |
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Subject: RE: BS: One for the astrophysicist From: Uncle_DaveO Date: 29 Jul 15 - 06:18 PM Did the stars form galaxies or galaxies form stars???? Neither. They were both formed by a process which all started with the reasonably assumed Big Bang. Stars are results, not active causes. Galaxies are other results, and didn't "cause" anything. Which class can be argued to have formed before the other is irrelevant. "Predecessor" is not the same as "creator". Dave Oesterreich |
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Subject: RE: BS: One for the astrophysicist From: Greg F. Date: 29 Jul 15 - 06:42 PM Put downs and mockery are not constructive ! Nor is belief in utter nonsense. I would offer that calling out nutters is rather more constructive than the futility of attempting to engage them in rational discourse. |
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Subject: RE: BS: One for the astrophysicist From: Rob Naylor Date: 29 Jul 15 - 07:37 PM Dave O : Which class can be argued to have formed before the other is irrelevant. "Predecessor" is not the same as "creator". Absolutely! |
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Subject: RE: BS: One for the astrophysicist From: Rob Naylor Date: 29 Jul 15 - 07:48 PM Pete: I should have thought that the only way you could conjecture a universe from nothing, is to change the definition of nothing. And I see that one of the earliest comments on the Krause video makes exactly that point He's not changing the definition of "nothing" at all. He means precisely what *you* would mean when he says that in a "flat" universe the total energy is zero, and that because of that the universe could actually self-generate from "nothing". He hasn't re-defined "nothing" at all. If you think he has then you're misunderstanding what he's saying. |
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Subject: RE: BS: One for the astrophysicist From: Mr Red Date: 30 Jul 15 - 05:17 AM a Galaxy is (was?) what we, in the UK, call a people carrier. (Ford variety, aka Seat Alhambra, aka Volkswagen Sharran). Which for the Milky Way we are part of, is very apposite. |
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Subject: RE: BS: One for the astrophysicist From: GUEST,Grishka Date: 30 Jul 15 - 05:20 AM There is no such thing as "a universe from nothing". Time itself is a function of the universe, as well known since Einstein's time. If the Big Bang theory holds, time starts "immediately" after it. Postulating anything "before" is as meaningless as dividing 1 by 0 (what mathematicians call a "singularity"). Spiritual ideas must be considered somewhat detached from physical time. "Eternal life" is such a concept. |
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Subject: RE: BS: One for the astrophysicist From: Jack Blandiver Date: 30 Jul 15 - 06:15 AM Scientific theory is informed & peer reviewed conjecture; as long as theory holds, then fine but once it is overturned, out it goes. Take Dark Matter, of which it is believed 96% of the cosmos must be composed because, according to Newtonian Dynamics, it wouldn't work otherwise. No one has ever seen Dark Matter; it's existence is purely mathematical. I was reading the other day about MOND (Modified Newtonian Dynamics) as postulated by Modehai Milgrom which could reproduce the rotation of galaxies without dark matter*. ESA are taking this seriously enough to launch a probe this autumn to put MOND to the test... For more see WIKI : Modified Newtonian dynamics * Bold type lifted from BBC Focus magazine 284, August 2015 p.82 |
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Subject: RE: BS: One for the astrophysicist From: GUEST Date: 30 Jul 15 - 06:37 AM So, what powered inflation? |
