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Cosmology nerdery

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Created by NotWal > 9 months ago, 10 Feb 2013
NotWal
QLD, 7428 posts
10 Feb 2013 7:21PM
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Hubble has spotted a galaxy 13.3 billion light years away. The universe was only 0.47 billion years old when that light set off.

One wonders if it's possible to spot the boundaries of the very early universe.

http://www.telegraph.co.uk/science/space/9682959/NASA-locates-most-distant-galaxy-ever-discovered.html

Mark _australia
WA, 22344 posts
10 Feb 2013 5:37PM
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How do they know how far away it is? It could be a big one farther away or a smaller one closer....?

Rupert
TAS, 2967 posts
10 Feb 2013 8:40PM
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Serious question;

How do ythey measure light years????

How accurate is this measuring device????

Or is it just so because a 'Scientist' said so????







Ian K
WA, 4048 posts
10 Feb 2013 5:43PM
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They've established that the universe is expanding, stars farther away are receding at a greater speed, so the red shift of the light they send out is a measure of distance.

hyperphysics.phy-astr.gsu.edu/hbase/astro/redshf.html

Mark _australia
WA, 22344 posts
10 Feb 2013 5:51PM
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Ian K said...
They've established that the universe is expanding, stars farther away are receding at a greater speed, so the red shift of the light they send out is a measure of distance.

hyperphysics.phy-astr.gsu.edu/hbase/astro/redshf.html



But given the varying and unknown composition of the medium (space) over such a large distance could that not also cause red-shift?

Also, some very well conducted experiments showed the speed of light has changed a bit (slowing) and nobody can refute it entirely (but most ignore it as it fks up soem of the theories we are fed as truth)

Ian K
WA, 4048 posts
10 Feb 2013 5:59PM
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Mark _australia said...
Ian K said...
They've established that the universe is expanding, stars farther away are receding at a greater speed, so the red shift of the light they send out is a measure of distance.

hyperphysics.phy-astr.gsu.edu/hbase/astro/redshf.html



But given the varying and unknown composition of the medium (space) over such a large distance could that not also cause red-shift?

Again, some very well conducted experiments showed the speed of light has changed a bit (slowing) and nobody can refute it entirely (but most ignore it as it fks up soem of the theories we are fed as thruth)


Scientists are a competitive lot, they spend a large proportion of their energy trying to find holes in each others theories. There's no conspiracy amongst cosmologists to feed us untruths. Why would they? The red shift theory will have stood up to a lot of effort to undo it. That's not to say it won't ever be undone. There's fame for someone who can.

Mark _australia
WA, 22344 posts
10 Feb 2013 6:09PM
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I will agree about trying to find holes in others theories for most sciences, but in theoretical physics and astronomy etc it seems to be quite the opposite. Anything that makes the universe old, very very large, and expanding, is well accepted. Anything to the contrary is discarded much more easily.

poor relative
WA, 9089 posts
10 Feb 2013 6:16PM
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Article says.....

Light from the newly discovered galaxy, which astronomers have named MACS0647-JD


What kind of name is that. Fkn nerds

Ian K
WA, 4048 posts
10 Feb 2013 6:26PM
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Mark _australia said...
I will agree about trying to find holes in others theories for most sciences, but in theoretical physics and astronomy etc it seems to be quite the opposite. Anything that makes the universe old, very very large, and expanding, is well accepted. Anything to the contrary is discarded much more easily.




A contrary theory has to agree with observations, if it has trouble accommodating observations it will be easily discarded. I stayed with cosmology as being the most self-critical of the sciences as none of its findings have applications that could be of interest to the commercial world.

"Wonders of the solar system" will be on SBS in 5 minutes, you'll have to wait another 3 hours Mark, I'll have the jump on you

Carantoc
WA, 6631 posts
10 Feb 2013 7:22PM
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Ian K said...

A contrary theory has to agree with observations....



Never been required before on Seabreeze forums, so why now ??

Certainly the Kite forum doesn't conform to any 'rational universe' theory

bundeep
14 posts
10 Feb 2013 8:34PM
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The thing i don't get is (and maybe its because i have been drinking a lot today), but if a solar system is measured as being 13.3 billion light years away (distance) and physics largely agrees that matter can't travel faster than light, then at a minimum it must have taken 13.3 billion years for that solar sytem to get that far away from the epi-centre of the 'big bang', then another 13.3 billion years for that light to travel back as far as earth so that we can see it.. Which makes the universe a minimum of 26.6 billion years old.. at least 13.3 billion years older than current estimates..

Does that make sense?

NotWal
QLD, 7428 posts
10 Feb 2013 11:27PM
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bundeep said...
...
Does that make sense?

No.
You have the big bang. This local region shoots off in one direction and the bit we're looking at shoots off in another. (Cosmologists wont put it like that but that's essentially what happens). We start looking around. All the light we see has aged because of the time it takes in transit. Light from distant things is older than light from close things so when we look at very distant things we are seeing them as they were a very long time ago. We can't possibly see that distant galaxy as it is now. We can only see it as it was 13.3 billion years ago and at that time it wouldn't have moved far (in terms of cosmic distances) from where it was post inflation.

mineral1
WA, 4564 posts
10 Feb 2013 9:38PM
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Latest therory indicates "NO" big bang, as there is no tell tail evedence left over to show it actually happened.
According to so called big Gurus of science, they are hinting on a rapid expansion, in preferance. Well they are, until one of them finds the missing chemical trail to support a big bang.

Mark _australia
WA, 22344 posts
10 Feb 2013 10:10PM
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The "Big Bang" has been gone for quite some time.

The trouble is, regardless of proof (or lack thereof) it is all taught as irrefutable fact and people forget it had the suffix "theory" attached.

Every schoolkid has heard of the Big Bang and it is in every textbook - but no cosmologist / astronomer / physicist etc really believes in it anymore.

That is what I was talking about - its more religion and philosophy mixed with pop culture than it is science.

NotWal
QLD, 7428 posts
11 Feb 2013 12:43AM
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Mark _australia said...
But given the varying and unknown composition of the medium (space) over such a large distance could that not also cause red-shift?

Also, some very well conducted experiments showed the speed of light has changed a bit (slowing) and nobody can refute it entirely (but most ignore it as it fks up soem of the theories we are fed as truth)

I would expect all the possibilities to be canvased however there is a history in cosmology of ignoring odd stuff until it becomes un-ignorable. There was a bloke who proposed a heliocentric solar system 500 years before Copernicus but he didn't get a look in. Fritz Zwickie recognized the existence of dark matter in the 50s but that was ignored until recently when accurate observation made it inescapable. Remarkably it accounts for 4 or 5 times as much mass as what we can see. It was thought to be garden variety dust rocks and gas but more recently it's believed to be something different like neutrinos. What it is is a mystery.

I don't know about speed of light changing. That would be taken with a great deal of skepticism I imagine because it's fundamental to the description of space/time.
Recently (2010?) there was an experiment done that involved shooting particles from Geneva to Italy (look up OPERA) and they recorded speeds that were a tiny bit over light speed. They checked their results from very many events and eventually decided to publish. It created a big stir. It was not well received by some who accused them of sensationalism and insufficient care with their experiment. Anyway a year or so later it was shown to be incorrect.

Light speed changes in different media and there is a lot of free hydrogen out there not to mention dark matter. That affects light with its mass but if it has refractive properties I don't know. Maybe there is room for error there. If light was red shifted more than expected that would give a distance/speed error. Red shift can be checked (calibrated) at local short distances using parallax and at then further distances using standard candles. I don't know if it can be checked for very long distances.

NotWal
QLD, 7428 posts
11 Feb 2013 1:00AM
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Mark _australia said...
The "Big Bang" has been gone for quite some time.

The trouble is, regardless of proof (or lack thereof) it is all taught as irrefutable fact and people forget it had the suffix "theory" attached.

Every schoolkid has heard of the Big Bang and it is in every textbook - but no cosmologist / astronomer / physicist etc really believes in it anymore.

That is what I was talking about - its more religion and philosophy mixed with pop culture than it is science.




That's not quite the case. The Big Bang is still part of the standard model. The CMAP WMAP is very compelling evidence for it. :
Wikipedia says:
The Big Bang is a well-tested scientific theory and is widely accepted within the scientific community. It offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background, large scale structure, and the Hubble diagram for Type Ia supernovae.[7] The core ideas of the Big Bang—the expansion, the early hot state, the formation of helium, and the formation of galaxies—are derived from these and other observations that are independent of any cosmological model. As the distance between galaxy clusters is increasing today, it is inferred that everything was closer together in the past. This idea has been considered in detail back in time to extreme densities and temperatures, and large particle accelerators have been built to experiment in such conditions, resulting in further development of the model. On the other hand, these accelerators have limited capabilities to probe into such high energy regimes. There is little evidence regarding the absolute earliest instant of the expansion. Thus, the Big Bang theory cannot and does not provide any explanation for such an initial condition; rather, it describes and explains the general evolution of the universe going forward from that point on.

Also "inflation" poses a big mystery.

Anyway if the BB theory has been shot down I'm not aware of it.
I'll have to have a hunt around.

Mark _australia
WA, 22344 posts
10 Feb 2013 11:07PM
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Motwal dude. I typed a lot and then lost it.

Just google it, there is a fk-load about speed of light slowing (from about 2002 - 2005) and the so-called retorts are pretty weak. Nil really, since as the grant $$$ are not to be found in debunking long-held beliefs are they?
Then suddenly about a year ago CERN had particles breaking the c barrier and what do we get? More theories, not a re-examination of the science that led to the observable conclusion that c may change.

No, suddenly photons are special and can do that (after being told for years nothing can)

It is ignored as the philosophy or religion of astrophysics starts with the pretext that everything is really really fkn old and expanding.

ANYTHING that may suggest otherwise is discarded as creationist claptrap or conspiracy theories.

Trouble is, claiming a photon to be massless and thereby able to exceed c - even briefly - means Mr Planck, or Mr Einstein, or Mr Schrodinger is wrong. The photon plainly and obviously has a wave nature and a particle nature so I am tipping it is NOT the latter bloke.

NotWal
QLD, 7428 posts
11 Feb 2013 1:17AM
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I'm very skeptical. I'll have a look around.

Oh yeah I meant to say that "theory" in science means a thoroughly tested hypothesis, in other words just about as close to "truth" as you can get while leaving a little wriggle room for future amendment. Its not the same as vernacular usage.

Mark _australia
WA, 22344 posts
10 Feb 2013 11:29PM
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^^^ don't waste too much of your life on it - nor hold your breath - every chance I am very bloody wrong lol

Then again, photons have a particle nature - they carry momentum FFS - yet they have been seen to exceed c.
Plus c has been shown to change (a bit) .......... and all this is ignored?

My point is simply that some good science is often ignored due to the prevailing assumptions held by 'the establishment'.
The fact that Nature published the research about the change in c is heartening - but the lack of proper counter-research is very sad. Seems it was ignored because it may not fit with our preconceived ideas - rather than being experimentally debunked.

pierrec45
NSW, 2005 posts
11 Feb 2013 3:05AM
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Mark _australia said...
^^^ don't waste too much of your life on it - nor hold your breath - I am 99.9% sure I'd be very bloody wrong lol

Then again, photons have a particle nature - they carry momentum FFS - yet they have been seen to exceed c.
Plus c has been shown to change (a bit) .......... and all this is ignored?

My point is simply that some good science is often ignored due to the prevailing assumptions held by 'the establishment'.
The fact that Nature published the research about the change in c is heartening - but the lack of proper counter-research is very sad. Seems it was ignored because it may not fit with our preconceived ideas - rather than being experimentally debunked.

Sounds all like a conspiracy, hard to believe.
Either said published article and others have formally proven that the speed has changed. And then, I doubt very much it would be ignored.

Else it's a theory like so many others, waiting to be proven or re-inforced.


the truth
QLD, 189 posts
11 Feb 2013 9:44AM
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Mark _australia said...

Trouble is, claiming a photon to be massless and thereby able to exceed c - even briefly - means Mr Planck, or Mr Einstein, or Mr Schrodinger is wrong. The photon plainly and obviously has a wave nature and a particle nature so I am tipping it is NOT the latter bloke.


this is great, does this mean I can have my cat back?

evlPanda
NSW, 9202 posts
11 Feb 2013 11:00AM
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^ We're not sure what state it's in.

mineral1 said...
Latest therory indicates "NO" big bang, as there is no tell tail evedence left over to show it actually happened.
According to so called big Gurus of science, they are hinting on a rapid expansion, in preferance. Well they are, until one of them finds the missing chemical trail to support a big bang.


It's no "latest theory". The Big Bang always was Rapid Expansion, and never anything else. There never was an explosion, nor was it thought there was. It was just some radio show where somebody called it "The Big Bang", the name stuck and has been a misnomer ever since.

evlPanda
NSW, 9202 posts
11 Feb 2013 11:26AM
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Mark _australia said...
Just google it, there is a fk-load about speed of light slowing (from about 2002 - 2005) and the so-called retorts are pretty weak. Nil really, since as the grant $$$ are not to be found in debunking long-held beliefs are they?


If you could prove that the speed of light is changing you'd be getting your research lab much fame and recognition.


Then suddenly about a year ago CERN had particles breaking the c barrier and what do we get? More theories, not a re-examination of the science that led to the observable conclusion that c may change.

No, suddenly photons are special and can do that (after being told for years nothing can)

It is ignored as the philosophy or religion of astrophysics starts with the pretext that everything is really really fkn old and expanding.

ANYTHING that may suggest otherwise is discarded as creationist claptrap or conspiracy theories.

Trouble is, claiming a photon to be massless and thereby able to exceed c - even briefly - means Mr Planck, or Mr Einstein, or Mr Schrodinger is wrong. The photon plainly and obviously has a wave nature and a particle nature so I am tipping it is NOT the latter bloke.


That was so last year. It was very exciting while they looked at what could have caused the readings to show particles traveling faster than light, and most importantly tried to reproduce it, because it would have shown serious flaws in our understanding of the universe. It was never reproduced and the mistakes were found, as everyone expected. Not as exciting as we'd hoped. (you can google it, it was probably the biggest story in science last year/no coverup)

The people that observed > c speeds said...
Despite the large significance of the measurement reported here and the stability of the analysis, the potentially great impact of the result motivates the continuation of our studies in order to investigate possible still unknown systematic effects that could explain the observed anomaly. We deliberately do not attempt any theoretical or phenomenological interpretation of the results.


You should write them Mark.

Skid
QLD, 1499 posts
11 Feb 2013 2:23PM
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bundeep said...
The thing i don't get is (and maybe its because i have been drinking a lot today), but if a solar system is measured as being 13.3 billion light years away (distance) and physics largely agrees that matter can't travel faster than light, then at a minimum it must have taken 13.3 billion years for that solar sytem to get that far away from the epi-centre of the 'big bang', then another 13.3 billion years for that light to travel back as far as earth so that we can see it.. Which makes the universe a minimum of 26.6 billion years old.. at least 13.3 billion years older than current estimates..

Does that make sense?


Matter cannot travel faster than light, but (I am told) space can expand at a rate faster than the speed of light...

I'm at work and don't have time to google and copy and paste, nor find a youtube clip (the standard seabreeze proof)
Just thought I would share anyway....

Macroscien
QLD, 6806 posts
11 Feb 2013 6:55PM
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I wish I could say something about this (Universe organizing)... but I am afraid that my theory will be instantly discarded based on English grammar mistake...
that is the problem with science... that must be always expressed in known linguistic form .. (this is a bit for me like painting beautiful landscape picture using watered down different shades of s**t.)

evlPanda
NSW, 9202 posts
12 Feb 2013 10:39AM
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^ Please don't let that stop you Macro.

NotWal said...

Hubble has spotted a galaxy 13.3 billion light years away. The universe was only 0.47 billion years old when that light set off.

One wonders if it's possible to spot the boundaries of the very early universe.


Your answer:

Skid said...
Matter cannot travel faster than light, but (I am told) space can expand at a rate faster than the speed of light...


No. You will never see the very early universe.

evlPanda
NSW, 9202 posts
13 Feb 2013 11:14AM
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...Hang on. No, that can't be right. You can't see light from the very early universe, like the first moments, because that took place right here, where this next comma is on your screen, and the light from that has since long gone ...except that space did expand much faster than light in the universe's early history ...so that very early light shone out (also) from a point that is now a long way away...

...I think it really depends on when this super rapid expansion took place, and how much it expanded in that short time. It will form a kind of horizon.

As for the universe expanding or not; everything is red. And not just light (aka energy) in the visible spectrum. This points to doppler shifting, thus everything is moving away from us. Sure, you can come up with some other theories, and people do all the time, that's science. But the most likely scenario is expansion. I don't know why people are all uptight about some "religion of science" that is above refute. If you can prove otherwise everybody will listen and the understanding of our universe will change. You can't just say "What about this idea? Why aren't you listening to me? I'm listening to me.", you have to actually prove it. At the moment the most likely scenario is the ill-named "big bang theory". Prove otherwise.

Macroscien
QLD, 6806 posts
13 Feb 2013 10:31AM
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evlPanda said...
No. You will never see the very early universe.

that is not necessarily true unless we discard time travel ultimately

Macroscien
QLD, 6806 posts
13 Feb 2013 10:47AM
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in mine theoretical model the only fundamental constant is the TIME. Other factors like forms of energy, forces and dimensions that we so carry about are derivatives only....
there are also few other factors that we are unaware or hardly poses means to calculate now (like entropy to start with)

dinsdale
WA, 1227 posts
13 Feb 2013 10:29AM
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Macroscien said...
in mine theoretical model the only fundamental constant is the TIME

Hmmm. Unfortunately TIME isn't a constant either. We/you can (with enough money) conduct empirical experiments to demonstrate time shift with speed.

It's been done.

Macroscien
QLD, 6806 posts
13 Feb 2013 12:39PM
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dinsdale said...
Macroscien said...
in mine theoretical model the only fundamental constant is the TIME

Hmmm. Unfortunately TIME isn't a constant either. We/you can (with enough money) conduct empirical experiments to demonstrate time shift with speed.

It's been done.



That is where common mistake lay (in such reasoning) because you do measure time using this derivatives variables... I leave it here for e-archaeologists to decide...



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"Cosmology nerdery" started by NotWal