BS: One for the astrophysicist

Subject: RE: BS: One for the astrophysicist
From: Jack Blandiver
Date: 03 Aug 15 - 04:46 PM

Goodness knows how young earth creationism came into this thread.

Might have been me. Did I point out that Newton believed the Cosmos to be around 10,000 years old? Of course he was operating within the limits and conventions of his time,the sort if thing that passed as learning rather than the entreated idiocy of young earth creationism of our present time.

Subject: RE: BS: One for the astrophysicist
From: Keith A of Hertford
Date: 03 Aug 15 - 03:53 PM

Thanks Dave, but I found this on the Hubble site,
"I wrote above that the space between galaxies is mostly empty because it depends on where one looks. Along the filaments and nodes of the cosmic web, there is some normal matter and dark matter, but at much lower density than in galaxies. In the voids, there is only extremely low density material."

Subject: RE: BS: One for the astrophysicist
From: GUEST,Dave
Date: 03 Aug 15 - 02:04 PM

Keith A says:

"There is very little matter between the galaxies.
The galaxies are clumps of matter within and from which stars formed."

Surprisingly, this isn't right. Even if you ignore the putative dark matter, if you look at a cluster of galaxies, there is about 6 times as much mass in hot gas (mainly hydrogen and helium, but also rather surprisingly including heavier elements) between the galaxies as there is in the stars in the galaxies themselves. We know this because the gas is hot and emits X-rays, which can be observed by X-ray satellites. But its only been known since about the 1980s.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Time stamp
Date: 03 Aug 15 - 01:47 PM

Goodness knows how young earth creationism came into this thread."
   That's nothing to do with me.You're obviously not quite understanding.That said you do have a point though I suppose,and not too fussed about challenging it.I'm done carry on.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Dave
Date: 03 Aug 15 - 01:40 PM

Time Stamp,

That is absolutely not back to the OP, the OP asked a reasonable question which I have attempted to answer, but in that answer I have to highlight disagreements. The OP did not once mention either consciousness or God, only stars and galaxies. Goodness knows how young earth creationism came into this thread.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Time stamp
Date: 03 Aug 15 - 01:24 PM

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."


From: GUEST,Time stamp
Date: 28 Jul 15 - 04:24 PM

". . . 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)" "

       Guest10:09 AM, I know you think you have made a point,and I can understand why you think that.But ... when I say consciousness I don't mean God.I do though understand why people would think it is the source or God of their culture when experienced in its purest form.
   Imo and a lot of others now and through the ages, for valid reasons, think/thought that if we can just get a better grasp/understanding on consciousness mankind will make a big leap in both science and our nature (what it is to be a human being).At the moment we live stunted half lives.
   Back to the OP,I'll say again when I say I think consciousness is the source of evolution, the universe,the all, I don't mean God as I've ever seen written. Attaching human qualities to what I'm talking about should be resigned to the past.
   If you want to expand further guest, start a thread.8)

Subject: RE: BS: One for the astrophysicist
From: GUEST,Dave
Date: 03 Aug 15 - 01:08 PM

Its no just clusters of galaxies of course, its the rotation of spiral galaxies, the motions of stars in the outer parts of our own galaxy, and a few other things. Historically the problem was discovered in clusters of galaxies by Fritz Zwicky.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Dave
Date: 03 Aug 15 - 01:04 PM

Pete,

Its quite easy to verify gravity (the inverse square law, which goes back to Newton and Hooke of course) on familiar length scales, and at familiar accelerations. Such was done by Henry Cavendish in the early 19th century, and he (probably) measured the universal constant of gravitation, G. Also Newton's model explains very well motions on larger scales, such as the motions of the planets. Or nearly. It was found in the 19th century that the precession of the perihelion of the orbit of Mercury. Einstein's theory of General Relativity modifies Newtonian gravity at high accelerations (thats a bit of an oversimplification) and it models the precession of the perihelion of Mercury very well. And predicts some other things later verified by experiment such as the gravitational deflection of light (those photos of gravitational lenses that the Hubble Space Telescope produces).

So thats all very well, but what about the limit of low accelerations? Low accelerations mean large distances, so here you can't make experimental verification on earth, or even on the Solar System (though there is the Pioneer anomaly). But if you look at the motions of galaxies in clusters of galaxies, then Newton's laws clearly don't explain these, unless you postulate a large amount of hidden mass. Dark matter, which we have never detected directly, despite a variety of very expensive experiments to do so. So either there is dark matter or there is a modification to Newton's laws in the low acceleration limit, hence there is a variety of opinions.

Subject: RE: BS: One for the astrophysicist
From: Greg F.
Date: 03 Aug 15 - 12:11 PM

established experimentally verified theories

And like evolution.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Pete frown seven stars link
Date: 03 Aug 15 - 11:42 AM

My grasp on all that is a bit tenuous , Dave . But I don't suppose there is so much variety of opinions as to established experimentally verified theories like gravity, for example.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Dave
Date: 03 Aug 15 - 10:17 AM

Which stars and which galaxies? Our own sun for instance is younger than our own galaxy, it is a Population I star (paradoxically one of the younger ones). It is a star which was formed out of a "solar nebula" already enriched with heavy elements (metals to an astrophysicist, for whom a metal is anything which is not Hydrogen or Helium). Its not a coincidence that we orbit one of the rarer Population I stars, as the elements with which they are enriched include all of those of which rocky planets are made, and all of those (bar Hydrogen) necessary for life.

It is likely that there were stars around before our galaxy was formed. All stars that we have analysed in our galaxy contain some heavy elements, even the older Population II stars. As far as we know these elements are only formed in stars, so there must have been an earlier generation of Population III stars, probably before any galaxies as we know them were formed.

Majority consensus is that the formation of galaxies is "bottom-up" rather than "top down". And the first things to form are dark matter halos, which form in small units and them merge to form larger ones. Gas accumulates in these dark matter halos forming stars and then small units (maybe like dwarf galaxies) which them merge to form larger ones. These bottom-up models are very good at explaining the spatial distribution of galaxies, less so their individual nature.

Having said that, there are a substantial minority of astrophysicists who would favour a different model, such as a top-down model which does explain better some of the properties of galaxies (for instance the concentration of heavy elements in their centres). And there are some as Jack Blandiver pointed out who would reject the need for dark matter altogether, preferring instead modifications (of which Milgrom's is the best known) to the theory of gravity.

Subject: RE: BS: One for the astrophysicist
From: GUEST
Date: 03 Aug 15 - 10:09 AM

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."


From: GUEST,Time stamp
Date: 28 Jul 15 - 04:24 PM

". . . 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)"

Subject: RE: BS: One for the astrophysicist
From: Keith A of Hertford
Date: 02 Aug 15 - 04:53 PM

.....though it would be dark until lit up by stars.

Subject: RE: BS: One for the astrophysicist
From: Keith A of Hertford
Date: 02 Aug 15 - 04:03 PM

Henretta,
A galaxy is a group of stars held together by gravity.

A galaxy is more than just stars.
If you swirled up a mass of hydrogen but somehow prevented stars forming in it, you would still have a galaxy.

Subject: RE: BS: One for the astrophysicist
From: GUEST,henryetta
Date: 02 Aug 15 - 03:33 PM

Actually, I think my post about galaxies and cities was right. We don't have time to write a whole book here, ya know.   

Guest is frustrated because my post took a little independent thinking.

Subject: RE: BS: One for the astrophysicist
From: EBarnacle
Date: 02 Aug 15 - 02:57 PM

I find it interesting that although people have been discussing gravity, the Big Bang, nebulae, etc. no one has mentioned turbulence. If the level of energy were flat, there would be no movement to encourage gravity to not only pull things together but to impart motion in other than linear directions.

Subject: RE: BS: One for the astrophysicist
From: GUEST
Date: 02 Aug 15 - 08:08 AM

Subject: RE: BS: One for the astrophysicist
From: GUEST,Pete from seven stars link
Date: 01 Aug 15 - 05:39 PM

" impolite" , bill ,IMO ,is putting it politely !

Subject: RE: BS: One for the astrophysicist
From: Bill D
Date: 01 Aug 15 - 12:18 PM

henryetta... "guest" was impolite, but if its post had ended at " It's entirely wrong. ", would you have felt better? And would you have explained or defended your assertion?

We need to discuss the facts, not politeness and/or attitudes.

Subject: RE: BS: One for the astrophysicist
From: GUEST,henryetta
Date: 01 Aug 15 - 09:23 AM

"inane crap"

Unnamed Guest, you're over the top, or else you've scraped bottom. Next time, try a little charm, and perhaps you'll acquire some beauty.

Subject: RE: BS: One for the astrophysicist
From: Bill D
Date: 31 Jul 15 - 06:36 PM

I am only dogmatic about exaggerations and careless logic & reasoning. I don't KNOW what all the answers are... but I am kinda dogmatic about my opinion that no one else does, either. ;>)

Subject: RE: BS: One for the astrophysicist
From: GUEST,Pete from seven stars link
Date: 31 Jul 15 - 04:11 PM

Well bill, that certainly seems a whole lot dogmatic than what krauss suggests.

Subject: RE: BS: One for the astrophysicist
From: Don Firth
Date: 30 Jul 15 - 06:16 PM

42.

Don Firth

Subject: RE: BS: One for the astrophysicist
From: Bill D
Date: 30 Jul 15 - 06:03 PM

Here's the thing folks.... we can build fancier telescopes, bigger Hadron colliders, faster super computers (new one just ordered) and play with all sorts of math & imaginative theories.... and we can thus learn more & more about what we can see and/or measure.

What we cannot do is come to any definitive conclusion about stuff we can't see, measure or find. This means that "dark matter" 'may' remain dark and never be more than a mathematical prediction. It means that multiple universes, "membranes", string theory and the big one... what came before there was anything.. may always be just interesting games.

Even IF someday there is a "theory of everything" that everyone likes and agrees with, universal agreement is not the sort of proof that science accepts. Edmund Husserl made the point that the **Philosophically prior question** is Why is there something, rather than nothing?. That is, it is the question that all philosophy reverts to if pushed far enough. This doesn't mean we know to go about answering it in any way that can't be disputed by anyone saying.."But what about THIS idea?"

We have notions of 'singularities' of 'Supreme Creators', of recurring Universes that expand & contract into ∞³... but our finite minds sometimes trick themselves into believing that once we name a concept, the concept has some sort of independent status... sort of like Plato's "forms".

We (some of us) invoke religious concepts to defend the idea that there must be a "first cause", and that it must be conscious, immortal, all-powerful...etc...all the properties that we can define as valuable, necessary, etc... that WE can name and conceive of. *shrug*... maybe... but 'it' has very little to say about the issue.

It's interesting to play with ideas... and more--or less--- interesting to observe, measure and create 'stuff'. It's also important to keep some perspective about which we are doing, and the limits of each.

Subject: RE: BS: One for the astrophysicist
From: GUEST,Pete from seven stars link
Date: 30 Jul 15 - 05:39 PM

I think I get what you are saying, grishka, but it seems to assume that there can be nothing, and then bang, there is something. I am not a scientist, but best I can see the Big Bang theorises the impossible.   So by my reckoning, the analogy is not 1 divided by 0 , but 0 divided by 0 !          And it seems to me that anyone who thinks 0 divided,added or subtracted by 0 , believes some superstitious stuff, as do the anti theists who a-priori discount a creator God. That don't strike me as being particularly scientific.

Subject: RE: BS: One for the astrophysicist
From: GUEST
Date: 30 Jul 15 - 01:55 PM

"27% dark matter, 68% dark energy, 5% normal matter."

And, a lot of "don't matter"
lol

Subject: RE: BS: One for the astrophysicist
From: GUEST
Date: 30 Jul 15 - 01:43 PM

A galaxy is a group of stars held together by gravity. It can be compared to a city, held together by human behavior.

I'm sorry??? That's about the most facile argument that I've ever heard. It's entirely wrong. Try doing some reading before posting inane crap.

Subject: RE: BS: One for the astrophysicist
From: GUEST,henryetta
Date: 30 Jul 15 - 10:41 AM

A galaxy is a group of stars held together by gravity. It can be compared to a city, held together by human behavior.

Q: Which came first, some buildings or the city?
A: The buildings.

Similarly, which came first, the galaxy or some stars? Answer is, the stars.

Subject: RE: BS: One for the astrophysicist
From: Greg F.
Date: 30 Jul 15 - 09:31 AM

Bravo Keith! That's the most intelligent post you've mde in months, if not years.

Subject: RE: BS: One for the astrophysicist
From: Keith A of Hertford
Date: 30 Jul 15 - 09:20 AM

(sigh)

Subject: RE: BS: One for the astrophysicist
From: Greg F.
Date: 30 Jul 15 - 09:16 AM

Keith MUST be right! All the living historians say so.

Subject: RE: BS: One for the astrophysicist
From: Jack Blandiver
Date: 30 Jul 15 - 08:25 AM

Sorry, Keith - I was lumping Dark Energy & Dark Matter together as (from what I can gather) both would be negated if MOND is accepted (although Dark Fluid Theory says Dark Matter & Dark Energy are one and the same thing). How does it work? As Vic Reeves would say : I don't know - but it does.

Subject: RE: BS: One for the astrophysicist
From: Keith A of Hertford
Date: 30 Jul 15 - 07:38 AM

27% dark matter, 68% dark energy, 5% normal matter.

Subject: RE: BS: One for the astrophysicist
From: GUEST
Date: 30 Jul 15 - 07:04 AM

"She believed in nothing. Only her scepticism kept her from being an atheist." 
― Jean-Paul Sartre

Subject: RE: BS: One for the astrophysicist
From: Jack Blandiver
Date: 30 Jul 15 - 06:45 AM

Time Stamp : 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

Just spotted this. All notions of God are subjective, belonging to the realms of superstition, make-believe, folklore, religion, mythology & general bafflement. They offend when believers attempt to make them objective; to make physical reality the subject of a fictional deity when nature needs no such a personage other than in terms of metaphor : even Stephen Hawking persists in his use of the term and in science the Cosmos is often referred to as Creation which I find unfortunate given the associations with fundamentalism & fundamentalist thinking on the whole.

That said, as an Atheist I know exactly what sort of God I don't believe in : Gods of myth and patheistic religion which become the only-too-human monotheistic idiot despotic God of Christian & Abrahamic Tradition. I do not preclude the numinous from the universe, but readily concede that, in human form, I am as likely to have any conception of it as our kitchen slugs have of the Large Hadron Collider. Through science, I feel communion. In the Egyptian Book of the Dead it says Existence is for all Eternity*; someone else said Matter can neither be created or destroyed. The material Cosmos is a wonder that inspires all wonder; in the face of which the human adventure really is only just beginning. Religion is the darkness into which science shines its light.

* Spot the quote folk fans! Actually, it's inscribed in hieroglyphics on the inner bag of Robin Williamson's 1972 solo album Myrrh. Did it make it onto the CD edition? I only have the vinyl, much cherished naturally...

Subject: RE: BS: One for the astrophysicist
From: GUEST
Date: 30 Jul 15 - 06:37 AM

So, what powered inflation?

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

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.

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.

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.

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!

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.

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

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 !

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.

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)

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?

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.

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.

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.