Cosmos

[Sammy G]

Brian Cox is nearer the mark, though he can all to easily loose mere mortals / plebs with some of his programs.

I've no problem with his presenting style; he's engaging, enthusiastic and obviously knowledgeable beyond belief.

What I do have a problem with is some of the fucking faces he pulls. Seriously, next Coxy documentary you watch - the guy can grimace for Britain, he really can. It's like watching a man wince from having his wounds bathed in TCP, albeit only for a microsecond or two, usually between sentences.

I've told people about this before and it's ruined Brian Cox for them.

 

[mydrugbuddy]

Ive never noticed that. Thanks, i probably will next time i watch him now. :D

 

[steewith2ees]

Even if you only have a passing interest in science all of the 'Wonders' series are amazing (although WOTUniverse is the best one), but they demand to be seen in high definition as the production values and locations are simply breathtaking. Apparrantly the first 2 series were only shot in 720p but compare it to any full HD blue rays or videos and its among the best.
Cant type no more - nodding out of tihis lush kit. Cant type a single word without having to delete it due to spellin'

 

[steewith2ees]

Going back to the new Cosmos it was introduced by the commander and chief and generally all round nice and clever guy, the POTUS Barrack Obama

 

[Josh]

It's a science documentary right? Might have to check this out as long as it's not some pants fiction!

 

[steewith2ees]

Yeh its a 13 part documentary series looking at cosmology and natural history

 

[Shambles]

Just caught up with the news that gravity waves were finally discovered this week. As physics and cosmology go, news doesn't get much bigger than that. Nobels a-go-go and a genuine big step forward. Actually finding physical evidence opens up a whole lotta very interesting stuff that existed only in the purely theoretical a week ago. We live in interesting times

It's a science documentary right? Might have to check this out as long as it's not some pants fiction!

Do yourself a massive favour and watch the original series too. A true classic of the documentary genre whatever the subject matter. If Carl Sagan can't invoke wonder and genuine awe in a person then said person is unlikely to be a person in any sense worth considering. A thing of beauty so it is

(and stands the test of time extraordinarily well despite being 30-odd years old and quite outdated on a factual level in several places - it's the overall feel and totally infectious passion, enthusiasm and - that word again - awe that it cannot fail to induce in anybody no matter their general interest in science)

Love stuff like that, i'll check it out

Am a big fan of Lawrence Krauss. He does tend to include a bit more technical detail than some of the popular science folk but don't let that put you off cos he's a funny fukker with it which always helps. Probably my fave talk of his - A Universe From Nothing. It is pretty difficult in places but is well worth sticking with cos I don't think you'll find anybody who manages to explain such difficult concepts in as entertaining and viewer-friendly fashion on this particular topic. Perhaps a step-up in terms of "difficulty" compared with Prof Cox and the like but well worth it cos is dealing with stuff that's nigh-on impossible to do justice to in traditional popular science form.

 

[F.U.B.A.R.]

I love all this nerdy shit! My idea of a good night in is smoking some good weed after the wife and kids have crashed out and trying to get my head around quantum theory, black holes and the multiverse. But please can someone answer the following question for me?

'Evidence of the expending universe is found in the fact that the light from all visible galaxies is 'redshifted', thus showing that all galaxies are moving apart.

However, it also seems to be accepted fact that the milky way and andromeda galaxies will collide in several million years time. This seeming paradox has been troubling me for some time now and I can't help but think I'm missing something really obvious here. Any ideas folks?

 

[Shambles]

AFAIK it's simply a case of local gravity being more powerful than Dark Energy over the relatively short distances involved between the Milky Way and Andromeda, FUBAR. Dark Energy (the stuff what redshifts things by "stretching" (or simply adding, perhaps) space) is a very small force that just happens to be additive so builds up to insanely powerful force over the very largest distances. Gravity is also a relatively weak force and is constant (I think - should probably double check that) but when two big ol' galaxies (and Milky Way and Andromeda are pretty hefty galaxies) are so relatively close it's considerably more powerful than Dark Energy over the short space. Longterm Dark Energy wins though and we all - everything in existence - gets ripped apart at the atomic level eventually. Possibly.

 

[F.U.B.A.R.]

Yeh, I follow that. But all the literature suggests that 'all' galaxies are redshifted, presumably including Andromeda. Regardless of the effects of dark energy (which is basically just a construct to make the equations work anyway), this can only mean that Andromeda, like all other galaxies, is receding from us. Am I correct or still missing something blinding obvious?

Or, is it the case that Andromeda is one of the few galaxies that isn't redshifted, thus suggesting that local gravitational effects have taken over?

 

[Vurtual]

^ Yeah, andromeda moving towards us is a local movement that overrides the expansion with relative speed or something. i think i remember reading that hubble first looked at andromeda and discovered a blue shift, then found the red shift everywhere else (might have remebred that wrong).

As far as the discovery announced yesterday, they were making way more of it on the news than it seemed to justify when i heard the details (like they said 'proof' of inflation or something which it seems far from at the moment). Also it's still after the big bang so says nothing about 'before' or anything. Gravity waves (if that's what they are) would be massive (har) though, as is being able (apparently) to look before the light started.

I just caught the end of something on Today this morning where they had Stephen Hawking talking about how it proves a bet he had with another physicist and he sounded quite upbeat about it; but they then talked to the geezer he had the bet with (Turok i think) and after hearing what he had to say, it all seemed less cut and dried (as science usually is i suppose).

i still have problems with some of the wish fulfilment they seem (to me as a layman) to have in big bang cosmology - like inflation itself (this possible proof notwithstanding, there's not, much explanatory power in it - it just happens somehow so the data fits); and dark energy and matter seem fishy too in that regard (and to some cosmologists too, not just idiots) - it just seems possible that something they haven't found out yet might be able to explain these things better somehow.

 

[F.U.B.A.R.]

Thanks shambs, a blueshifted Andromeda would make much more sense, it's just that I've never read anything suggesting that myself. You're right about today's news as well. All that's really happened is that they've found some trends in a certain set of data which happens to fit the predictions of one hypothesis. However, a supported hypothesis does not a proven theory make! Fuck it, I'll shut up now as I'm far too pissed to think about this clearly..

 

[Shambles]

Vurtual: True enough. Ask more or less any two cosmologists and you'll get varying degrees of enthusiasm about the gravity wave being such a big deal depending on their own pet theories. Just on the simple matter of actually finding the things after 100 years is a big enough deal really though. The folk who actually made the discovery didn't seem to be making any claims about "proving Big Bang" on the short interview I caught - think that's more media hype trying to make it a more easy to follow/understand/contextualise story for the masses. Haven't heard any actual scientist claiming it "proves Big Bang" (not that I've looked) and doubt there'll be many aside from those who are seriously invested in it being the case. Scientist-types tend to be a lot more cautious and conservative with such claims. Closest I've heard is one fella (don't recall the name) saying that it makes for good... what was the word he used... circumstantial? no, wasn't that. Secondary-type evidence. Suggestive rather than cast-iron.

I get where you're coming from in regards to certain theories being more a case of fitting with facts than necessarily explaining a great deal but I do think a lot of that comes down to simply not being able to follow the mathematics backing it all up. As mentioned, scientists are a notoriously cagey bunch (aside from the more flamboyant-types sometimes, perhaps) and don't like to stick their neck out too far without making sure their arses are covered on the figures.

I can only go as far as description, analogy, metaphor and the like and wouldn't pretend to be able to be able to really explain any of this stuff properly, but I do tend to more or less go along with Big Bang, Dark Energy and Dark Matter being 'Things'. As in I expect all three actually exist/happen(ed). I do agree that - certainly as far as pop science goes - it gets very tricksy with the Dark ones - especially the Energetic fella. New DM theory I was reading about this morn seemed to be the best one I've come across so far (as far as I can follow) purely because it's one of the only versions I can think of that doesn't - inexplicably - assume that all DM consists of a single particle type. Can't recall what they're calling this version of the theory but it seemed - to my tiny mind - to be somewhat reminiscent of anti-matter in that she was talking about a series of interacting particles. Very much akin to the visible universe only not visible - just getting on and doing its thing quietly but with genuine complexity which seems to be lacking from the versions that put it all down to WIMPs, neutrinos or sneaky lil black holes or whatever. Given the sheer quantity of the stuff, the chances of it being all easily explained away by finding a new particle of two seems a bit of a stretch. Something with comparable complexity to the visible universe seems far more likely to me. Or even more complexity - there is, after all, an awfy lot of it compared to what we get to see

Or, is it the case that Andromeda is one of the few galaxies that isn't redshifted, thus suggesting that local gravitational effects have taken over?

Yup, what Vurtual said. It's just that it gets a bit oversimplified sometimes. Not all galaxies are redshifted, just the vast majority. Ones that are locked into collision courses are still gonna... fly right through each other back and forth several times looking all pretty like...

NSFW:

EDIT: And I would be the one with the bright red avatar, the fella you're responding to in that last comment would be Vurtual. Just goes to show how much difference an avatar makes. Perhaps DM simply hasn't gotten around to choosing its avatar yet either.

 

[Vurtual]

Dark matter's main evidence i think is the fact that stars on the edge of galaxies are orbiting at a different speed than they should according to newton's gravitation equations - as if they weren't at the edge, but only a bit of the way out. To make the maths work they have to add 95% more (dark) matter; now they look for (and still don't find) candiates to fit that - but at the same time they should also try to explain what they can see, not what they think they should see. Maybe gravity works differently at large distances, or falls off with some sort of curve (childishly simple thought i know - i'm sure it'd be module 1 on a cosmology course).

Same with inflation - to fill the gap between the calculated mass of the universe and the speed of the expansion now, they have to add a massive amount of energy in inflation (and now dark energy to account for the acceleration), and they hope to find evidence later. Another childishly simple thought - maybe what we see as a big bang is actually some sort of horizon - maybe if we went back 10 billion years it would still look like the big bang was 14 billion years before (probably module 2... cosmic microwave background? i need to read some more cosmology again).

I like Roger Penrose's idea i heard on a horizon (and probably remembered wrong) - where the universe expands until all the matter eventually turns to photons - and because photons don't register time or distance (because they move at the speed of light i guess) there is no scale and so the universe becomes a point again and then explodes out in another big bang (very hinduish)

 

[F.U.B.A.R.]

Ah, you're correct, I was responding to vurtual - for some reason I thought you were Shambles. See, told you I was too pissed for this ....

 

[Shambles]

I like Roger Penrose's idea i heard on a horizon (and probably remembered wrong) - where the universe expands until all the matter eventually turns to photons - and because photons don't register time or distance (because they move at the speed of light i guess) there is no scale and so the universe becomes a point again and then explodes out in another big bang (very hinduish)

Yeah, heard that one recently too and has a certain appeal to it. With some of the more exotic elements of cosmology aesthetic appeal is probably as good a reason as any to look into such things. The universe is a spectacularly odd thing but most definitely has a supreme sense of style about it.

As for your other two points, I'm fairly sure you're selling both short by quite some considerable distance. Is way more evidence for both than you suggest but I'd have to rustle up a properly researched post to justify such a claim and that ain't happening right now so will leave it at seeing where you're coming from but expecting you may change your mind if you delve a lil deeper. Unfortunately, the more interesting evidence for any and all theories tends to not make it through to the vast majority of pop science stuff and - although it is out there elsewhere - is not so easy to explain, understand or discuss without the technicalities which I know damn well I can't do justice to. Is why I mostly watch uni lectures on PooToob for my sciencey stuff now - pop science proggies are great stuff, gorgeous to look at, nice to have a variety of approaches to explaining the basics... but that's as far as they can realistically go. To have a hope of going a bit beyond Prof Cox you kinda have to go for drier, more technical, more "difficult" stuff that you know you can only really grasp around the edges. But with enough edges I think you can build up a reasonably good outline of the actual theories rather than the very barest of bones of 'em.

 

[F.U.B.A.R.]

The main problem I have is that I don't understand the maths behind the theories. However, surely maths is just a tool to help understand reality. If reality doesnt fit the maths, surely that would indicate the maths is wrong? Instead, mathematicians like to invent new 'realities' just to fit their maths! As a layman, I would say that the biggest obstacle to understanding the universe is the maths!

 

[Shambles]

Hehe. Unfortunately I don't know the maths well enough to know whether that quite works out or not, FUBAR

I am acutely aware that if I had better maths knowledge (a lot better maths knowledge) I'd have considerably better understanding than I do - maths is the language the universe appears to speak whether us amathic-types like it or not

Somewhat annoyingly, I was actually dead good at maths at school but opted to take the lower course so I could have more time to get fukked with mates at college rather than being in lectures. This probably explains a lot about a lot for me 8)

 

[Vurtual]

Shambles - Yeah i definitely need to catch up on more recent detailed cosmology stuff - i did read quite a lot of it years ago and so do remember it was more nuanced than my above post makes out; but i was still agnostic on the main points even when more up to date as i remember (i wasn't just arrogantly disagreeing with geniuses (well maybe a bit) - there are physicists/cosmologists with differing theories).

And Fubar - i don't really think fully understanding the maths should be a barrier to a good explanation - some would say if it can't be explained in relatively simple terms it's probably not correct in some way (Einstein i think). That's not to say there shouldn't be hard maths involved, just that the maths can be explained in principle without having to calculate it in person. - like i understand the maths of fractals (which is actually quite simple) but i need a computer to calculate it and see a fractal.

 

[F.U.B.A.R.]

I think that mathematicians just get off on the fact that no fucker understands what they're on about - and they wanna keep it that way. As soon as a non-mathematician starts to grasp a particular concept, they have to muddy the waters by introducing more ridiculous maths. They're all Cunts I tell thee..