the big bang (sorry)

[kev100]

So … I’ve been thinking about the big bang … (sorry)

A couple of weeks ago we had some friends visiting, and, as it was moonless and clear, we set up the 10in dob and had a look around. Nice star clusters, the odd galaxy, and then the ring and veil nebulae, whereupon I began waxing lyrical (there was some wine involved), about how stars fuse hydrogen into helium, and then the heavier elements of the periodic table, until they ultimately explode and seed the galaxy with these elements, which then go on to form planets, and, ultimately, us …

At some point in the evening it dawned on me that, as the heavier elements are produced in stars, the ‘big bang’ must surely then have produced only hydrogen … If that’s the case, the notion I’d always held about the big bang (that all the matter in the universe was squeezed down into something incredibly dense and massive, the size of a grapefruit (or smaller), and then exploded and sprayed out all this star- and galaxy- and planet-forming stuff), is wrong. All the BB made was hydrogen …

I imagined a scenario akin to the beginnings of life on the planet, with simpler particles (somehow existing or coming into existence in a … what? A cosmic void?), coalescing through electro-magnetic, nuclear and gravitational forces into hydrogen atoms, whereupon gravity can begin to take over … whereupon when enough hydrogen had accrued, there was a gravitational collapse/explosion … the noise/light from which we refer to as the big bang, shows up in the cosmic background radiation.

Obviously this raises some questions:

If time and space as we know them were created in the BB/expansion of the universe, is there anything we can know about the earlier (if it existed) particle-filled void? How long does it take for enough hydrogen to form out of ‘nothing’ to gravitationally collapse? Presumably if such a gravitational hydrogen-based collapsed happened ‘somewhere’, once, it could have happened ‘elsewhere’, twice (multiverse?) … Is there a big, cosmic ‘room’ filled with bubble-like ‘universes’?

Am I even right in thinking that what we refer to as the big bang produced only hydrogen?

Is it possible for sub-atomic particles to appear our of nowhere/nothing? I seem to remember reading something to the effect that such particles do indeed behave in this way.

Does this mean the ‘universe’ is much, much older than we imagine?

Is any of this even remotely accurate?

Kev

[Peter Drew]

Perhaps this theory could be made into a TV series.   

[Knight of Clear Skies]

21 minutes ago, kev100 said:

At some point in the evening it dawned on me that, as the heavier elements are produced in stars, the ‘big bang’ must surely then have produced only hydrogen … If that’s the case, the notion I’d always held about the big bang (that all the matter in the universe was squeezed down into something incredibly dense and massive, the size of a grapefruit (or smaller), and then exploded and sprayed out all this star- and galaxy- and planet-forming stuff), is wrong. All the BB made was hydrogen …

The Big Bang produced hydrogen, helium and a dash of lithium (with perhaps very small quantities of heavier elements). It took me quite a while to understand why. Essentially, while the initial state after the BB was very dense it was also too hot for nuclei to form - any that did were immediately blasted apart. It's only as the universe expanded and cooled that the first elements formed, but at this point the density wasn't high enough to make heavier elements.

If you're interested in this I'd recommend this book, it's short, very readable and extremely informative.

[SilverAstro]

22 minutes ago, kev100 said:

All the BB made was hydrogen …

Nope !

It made some Helium as well, in fact the ratio of Hydrogen to Helium is one of the tests of the form of the Big Bang the rate, expansion etc. (and to exclude the various steady state theories)

I think a teense-weeny amount of Lithium was made as well, but that does not seem to get much mention these days ? I could be wrong on that.

That will do for starters ?

xxed in post with the Knight !

[Ouroboros]

As I understand it the Big Bang represents the moment of creation of energy, time and space. The energy converted into matter in the form of quarks, electrons etc.  There was an inflationary phase in which the universe expanded faster than the speed of light and eventually the hot plasma cooled enough for quarks to form particles like protons and eventually hydrogen.  I seem to recall that some helium was also created in the Big Bang. As I understand it Guth's inflationary theory implies big bangs are occurring continuously and a multiverse containing an inestimable number of parallel universes. 

[ronin]

Started with energy, matter came along later, not a lot later but later. E=MC**2 , swap it round to get M=E/(C**2).

Something recently said that Energy in effect was the BB, this "condensed" into Quarks, these combined and formed the stable hydrogen neculei and a few were able to make it all the way to Helium. Likey chance collisions and random chance.

However you now have to take into account that something like 80% of it appears to have made "Dark Matter". So in a way it could be that Dark Matter is/was easier to make then Hydrogen and that was easier to make then Helium. One talk I made it to it was said that the idea is that most likely Dark Matter is a single partical. Which would I suppose make reasonable sense. Just what its make up is is as yet unknown.

The other aspect is that it wasn't a Bang and was microscopically small. So not big either. The term "Biig Bang" was abit of a joke phrase used by Fred Hoyle, who did not believe in it. The joke was it stuck.

[kev100]

Thanks all for posting on this, and thanks for recommending the Marcus Chown book (ordered a copy straight away, and can't wait to read it).

Cheers,

Kev

[Ouroboros]

A very good book on this topic is Alan Guth's The Inflationary Universe. It's quite old now, published in 1998, but it's very readable though a somewhat long explanation of the theory of inflation plus a good amount of background on the Big Bang theory, cosmic microwave background and so on. At the time when I read it, maybe two years go now, I felt I grasped why the theory of inflation was necessary, how what we observe seems to verify it, and how it implies all sorts of interesting things like the concept of the multiverse and so on. I'm a bit hazy on it now with the passage of time. There are probably more modern popular books on the subject now, but it would be worth picking up second hand or from a library. 

[Ouroboros]

....... And another thing  last night the Beeb repeated Brian Cox's programme on the Universe in which he explains where the elements came from, nucleosynthesis in stars and supernova. Available on iplayer I imagine. 

[SilverAstro]

Or get it all online ! by googling "ratio of hydrogen to helium" 

Quote : The modeling of the production of helium and the hydrogen-helium ratio also makes predictions about other nuclear species, particularly ⁷Li, ²H(deuterium) and ³He. These observed abundances simultaneously fit the big bang model within a narrow range.

from http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/hydhel.html

 

[Ravenous]

1 hour ago, SilverAstro said:

Nope !

It made some Helium as well, in fact the ratio of Hydrogen to Helium is one of the tests of the form of the Big Bang the rate, expansion etc. (and to exclude the various steady state theories)

I think a teense-weeny amount of Lithium was made as well, but that does not seem to get much mention these days ? I could be wrong on that.

That will do for starters ?

There's also some suggestion a very small amount of other stuff too, like some isotopes of beryllium (I've heard suggestions cosmic rays provided some of the energy):

https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis

All this started ten seconds after the bang according to the above article....

And there's a well-known "periodic table" indicating where various elements came from:

https://en.wikipedia.org/wiki/File:Nucleosynthesis_periodic_table.svg

(By the way, it doesn't mention it but Helium is still being produced in small quantities within the Earth, from radioactive decay apparently...)

[SilverAstro]

1 minute ago, Ravenous said:

 Helium is still being produced in small quantities within the Earth, from radioactive decay apparently...)

Yes ! the only problem is we are using it up (party balloons being a big prob. ) faster than it is being produced

So we'll have to go mining the sun in the future, ( now where is that chap Cox when you need him, he knows something about getting close to the sun lol! )

Last time I thought about Helium abundance was when Fred Hoyle was having his Big Argument about the BB

39 minutes ago, Ouroboros said:

 I felt I grasped why the theory of inflation was necessary, how what we observe seems to verify it,

 to explain why the universe appears homogeneous and isotropic ?

[SilverAstro]

12 minutes ago, Ravenous said:

from radioactive decay apparently...)

oops I meant to add :- Alpha decay, to distinguish from beta decay (electrons) and gamma decay (photons)

[jabeoo1]

2 hours ago, Knight of Clear Skies said:

If you're interested in this I'd recommend this book, it's short, very readable and extremely informative.

Brilliant book !.  A  firm favourite of mine.  After that book try Gravity's Engines by Caleb Scharf its eye opening.  

 

[Ouroboros]

15 minutes ago, SilverAstro said:

.... to explain why the universe appears homogeneous and isotropic ?

Yes, that's part of it. But there are other reasons a simple Big Bang explanation doesn't work. Magnetic monopoles or something. Sorry, it's all a bit vague now. It all made sense when I read it.

[ollypenrice]

Another fan of The Magic Furnace here. I must re-read it.

I like Ronin's point that the big bang wasn't big and wasn't a bang! Excellent.

Right, said Fred.

Olly

[saac]

Ok there may not have been a bang but I'm not so sure that it wasn't big.  After all when it happened  everywhere in the universe. Doesn't get bigger than that  If you happen to find yourself in Geneva drop into the CERN visitor centre; they have an excellent public exhibition with high tech visual effects on the BB. 

Jim

[kev100]

Hiya, and thanks again to everyone who posted. It's funny that I'd gotten so stuck in the notion that the BB only created hydrogen, and found myself wondering how everything else could have formed from that homogeneous state. Forgetting, of course, about the temp and energy conditions at the time of the BB. Can't wait to read Marcus Chown's book when it gets here.

Kev ?

[Knight of Clear Skies]

For anyone interested in astrophysics, I'd also recommend Ethan Siegal. He's a great explainer, I credit his online articles for teaching me the rudiments of Inflation, and why it's a very solid theory.

[saac]

Kev, there is a very good BBC Horizon programme called "Cosmic Dawn" which focuses on the significance of the stage of evolution of the universe when it became transparent.  It's very watchable and covers exactly what you are asking. At the moment thought it is not available on the BBC iPlayer although it is probably available to purchase through the BBC store.  

Jim

[kev100]

Thanks Jim, I'll watch out for it.

Kev

[kev100]

Actually, a very quick Google and ...

 

[saac]

Good find Kev, hope you find it informative. I use it in class and find the ideas it puts across very useful in supporting the Big Bang theory.

Jim 

[SilverAstro]

That one appears to be talking about when the first stars lit up, which is a long time after when the Universe became transparent, when the CMB was created. If it is the one I remember it also contains some fantastical creation myths.

[SilverAstro]

4 hours ago, Knight of Clear Skies said:

I'd also recommend Ethan Siegal. He's a great explainer, I credit his online articles for teaching me the rudiments of Inflation,

looks like a nice find but it only let me read one story (the one about Voyager and the wrong pulsars!)  this month !! Ok now after re-boot my browser