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rambo07
2005-Mar-27, 12:11 PM
How can we really tell how old the universe really is? ,for example ,recently astronomers have peered into the furthest depth of space only to find gaxlaxies just like our own ? surprised , this shouldn't be ....... but think just for one minute ,how long do stars last anyway, if stars have a life cycle of say 10-15 billion years and then blow up to form new stars is it not surprising that when we look back in time we see mature galaxies ; this knocks two assumptions ,1. that the universe is dying. 2. that the universe is 13.6 billion yeasrs old.

antoniseb
2005-Mar-27, 01:33 PM
Originally posted by rambo07@Mar 27 2005, 12:11 PM
recently astronomers have peered into the furthest depth of space only to find gaxlaxies just like our own ?
Welcome back Rambo07,

Can you give a URL to a paper about finding galaxies "just like our own" from the "furthest depth of space". My understanding is that the most distant galaxies are quite unlike our own in may respects.

I think that the 13.7 billion year age will hold up pretty well, though I look forward to the relase of the WMAP year two and three data with polarization studies included to help give the date more narrowly.

rambo07
2005-Mar-27, 03:35 PM
I was refering to the view that when astronomers looked back to 300 million years after the so called big bang , they were surprised to see galaxies ( at all) , you say that these galaxies are different in many ways , I,m more interested in them being similar in some ways,,,,,, the big bang theorists are always chopping and changing the goal posts to suit there needs , perhaps you should look more closely how similar these galaxies are rather than the negative

antoniseb
2005-Mar-27, 03:55 PM
Originally posted by rambo07@Mar 27 2005, 03:35 PM
I,m more interested in them being similar in some ways
Similar in some ways is not

gaxlaxies just like our own

Yes there are some similarities, but in your previous post you were using the tactics of sensationalist journalism to essentially make a false claim to get attention.

I do not think that we've seen galaxies from 300 million years after the big bang yet, but I understand your point that earlier than previously expected there must have been star-forming galaxies.

I would point out that this does NOT change the fact that we ARE seeing cosmic evolution. There is a difference in the nature of galaxies from the earliest days to now, thus any steady-state explanation for the universe is ruled out. Also, what we see is what really happened, and no longer just hand-waving theories. It has always been the case that there were big error bars around estimates for the date of the first stars and the first galaxies.

rambo07
2005-Mar-27, 04:27 PM
if you look at this galaxy most stars within it are roughly the same age , if they die ,roughly at the same time and then shortly afterwards ( in galactic terms) give rebirth to new stars , then old galaxies may at a distance look new?, my view is that galaxies evolve not die , if you take this a step further at most galaxies , you might see that most galaxies at one time or another appear new ( together) or old

GOURDHEAD
2005-Mar-28, 03:44 PM
There is a difference in the nature of galaxies from the earliest days to now, thus any steady-state explanation for the universe is ruled out. Also, what we see is what really happened, and no longer just hand-waving theories. In general I agree; however, can we be sure there is no scale at which a steady state perspective is totally disallowed? For instance, a series of big bangs each followed by expansion, then collapse, then big bang, etc. Also, there may be a limit to spacetime warping allowed such that black holes, above some critical mass and the accompanying Lens-Thirring effects, erupt spewing quark-like, maybe even subquark-like "stuff" which subsequently "decays" into hydrogen thus renewing galaxy formation. It should be difficult to avoid observing such an event should one occur within the limits of our observable section of the universe. At the limit the two processes may be identical, the currently observed accelerating cosmological expansion rate notwithstanding.

Has anyone estimated the age of the presumed youngest galaxy?

antoniseb
2005-Mar-28, 06:14 PM
Originally posted by rambo07@Mar 27 2005, 04:27 PM
if you look at this galaxy most stars within it are roughly the same age , if they die ,roughly at the same time and then shortly afterwards ( in galactic terms) give rebirth to new stars , then old galaxies may at a distance look new
Star in this galaxy were not all born about the same time. There was a long period of intense star birth from eight billion to 5 billion years ago, spanning 3 billion years, but there are many stars older than 8 billion years here, and all the bright ones are much younger than 5 billion years.

Also, stars go through the main sequence in a wide variety of times, from a few million years for the hotest to 100 billion years or more for the dimmest. There will be no sudden episode of all stars dying, and a new phoenix-like galaxy springing from the ashes. Also, the ashes have a chemical signiture visible in the spectrum as reduced Hydrogen and much higher abundances of other materials.

Your vision could use some fine tuning to make it match observations.

antoniseb
2005-Mar-28, 06:20 PM
Originally posted by GOURDHEAD@Mar 28 2005, 03:44 PM
For instance, a series of big bangs each followed by expansion, then collapse, then big bang, etc.
Of course you could call this a steady state, but this does not represent the steady state universe idea in which there is no cosmic expansion going on, and galaxy redshift is an artifact of some other process.

As to lens-thiring effects erupt spewing quark-like, maybe even subquark-like "stuff" The central black holes in galaxies only account for less than one part in a thousand of the total mass of the galaxy. I'm not sure how they could ever spew enough stuff to create a new galaxy, nor do I know from this description what would become of the cinders of the old galaxy.

rambo07
2005-Mar-28, 07:03 PM
My argument is generalized ,and yet many a great scientist/astronometer will also argue that the universe will die when all the stars burn out? how can this be true if you are saying that stars are not born or die together and not in the same time scale , this would suggest that galaxies could live forever ?

antoniseb
2005-Mar-28, 07:22 PM
Originally posted by rambo07@Mar 28 2005, 07:03 PM
this would suggest that galaxies could live forever ?
Imagine that the universe started out being 90% Hydrogen, and 10% Helium by weight, with a tiny bit of Lithium.

Suppose that over the first 13.7 billion years, 10% of the total Hydrogen has been converted to Helium, and that 25% of the new total amount of Helium has been converted to heavier elements. And that slowly, clouds of the original mixture are getting trapped by galaxies and being turned into new stars, and likewise converted.

Slowly, the total amount of Hydrogen available to create new stars is being used up. Some of it is getting blown into intergalactic space where it may never get used to create new stars. But one way or another, there will be no new material to make viable stars. That day is a long time from now.

Note well: the percentages I suggested above are wild guesses. It might be possible to look up professional estimates of these numbers, but I took the lazy way here, and just used hypothetical numbers.

John L
2005-Mar-28, 09:18 PM
And to add to what Anton said, that amount of time - to use up all of the usable hydrogen - is on the order of billions of trillions of years. In the end, the last remaining stars will be cool red dwarf stars that can last many billions of years longer than our sun, cooling white dwarfs, neutron stars, and black holes.

Vega 44
2005-Mar-29, 02:22 AM
Also, Rambo, not all stars blow up (into Nova's and Super Nova's). The massive giants do so spectacularly but they live only millions of years. Medium mass stars like our sun blow off their outer layers to form a planetary nebula and live 5 to 15 billion years. And dwarf stars don't do either. They just burn for tens of billions of years and eventually burn out. So the statement that stars live 10 to 15 billion years and then blow up is incorrect.

rambo07
2005-Mar-29, 09:10 AM
the way i understand it ,that when we look back in time we still see galaxies, yes they are different and ( how i understand) are full of young stars and these galaxies are hydrogen rich , but have we looked at these galaxies to see if there are different stars there ,like the one's today ;it puzzles me that at the start when everything was fresh and new that 13.7 billion years later we have so many different stars ,also hydrogen can be recreated ,maybe by blackholes????

antoniseb
2005-Mar-29, 04:21 PM
Originally posted by rambo07@Mar 29 2005, 09:10 AM
also hydrogen can be recreated ,maybe by blackholes????
Black holes will not create Hydrogen in appreciable quantity. Also, I don't know what fraction of the Hawking radiation comes out as protons able to escape the black hole forever, but I bet it is a very small fraction.

Nereid
2005-Mar-29, 05:29 PM
This thread is beginning to resemble the 'Heat Death (http://www.physicsforums.com/showthread.php?t=67392&page=1&pp=15)' thread elsewhere ... present-day physics might give some pointers to the next 100 trillion years or so, but then in the 4321st century, one of the descendents of a UT poster may make a break-through discovery about hyper-fractal nature of branes^googleplex that makes all our discussions today meaningless ... and that is not even 100,000 years into the future! Image what might be found 100 billion years from now!! :P

antoniseb
2005-Mar-29, 05:50 PM
Originally posted by Nereid@Mar 29 2005, 05:29 PM
This thread is beginning to resemble the 'Heat Death (http://www.physicsforums.com/showthread.php?t=67392&page=1&pp=15)' thread elsewhere
Excellent point. As it is, there are several recurring ideas that keep coming up, but it is not practical to put up a frequently asked questions thread with pat answers. People who want these answers never look at such things, believing their ideas and worries to be new and original.

This long term extrapolation of what will happen to the universe is one of the most frequent broad categories, and like you have pointed out... there are important things we don't know about this, so any statement is merely based on some current plausible model. For example, any talk about heat death in trillions or quadrillions of years assumes that the Big Rip models (let alone other more alternative ideas) are wrong.

mas_to
2005-Mar-30, 09:35 AM
hi,
if the most distant light we see is emitted by some thing 13.7 b ly away and big bang theory is true, is those object had some age too. I mean they must travel for some time to get there (assume that we are at the central of universe) and universe must be older than 13.7 b ly
or I got wrong in understanding that "WMAP" thing

mas_to
2005-Apr-07, 11:11 AM
?

Guest
2005-Apr-07, 01:26 PM
yes i agree , but what about the evolution of stars as well ,we have found that some stars to today can last 10's of billions of years , while others may only have millions of years to live ;and that there are so many different sorts ,how did we get to this state of evolution in only 13.7 billion years ( in universal terms ,in the life and death of a universe 13.7 billion years isn't very long) what makes us so sure we have our timing of the birth right? ,when we are still seeing galaxys 13.4 years ago ? some things don't add up do they !!! this is why I am interested to see if these early? galaxys hold different stars like the ones today !!!!! also how long does it take a black hole to form a galaxy ? how do galaxys form ? do black holes create galaxys ? if they do how ? ( ie rub two black hole's together do you get star formation ???) or do black hole's use dark matter as a base to form a new galaxy ?

rambo07
2005-Apr-10, 08:55 AM
maybe the universe is only as old as far as we can see ? get a stonger lens see an older universe ! this doesn't solve anything , but proves that when it comes to deciding the age of the universe we havn't got a clue !.

imported_WINSTON
2005-Apr-12, 03:40 AM
Can you give a URL to a paper about finding galaxies "just like our own" from the "furthest depth of space".

These are the Hubble pictures fron NASA's "picture of the day" archives. These are 15 billion light years away (15 BILLION YEARS OLD) and show what we see today.

They do NOT show(as big bang would tell you):
1 Ten thousand times compression of today
2 Ten thousdand times heat of today
3 rapid expansion (in fact gallaxies are moving together to form clusters as they do in present era).

http://antwrp.gsfc.nasa.gov/apod/ap980607.html

http://antwrp.gsfc.nasa.gov/apod/ap981012.html

Bonus points:THESE GALAXIES SHOULD NOT EXIST
http://antwrp.gsfc.nasa.gov/apod/ap980607.html

antoniseb
2005-Apr-12, 03:52 PM
Originally posted by WINSTON@Apr 12 2005, 03:40 AM
These are the Hubble pictures fron NASA's "picture of the day" archives. These are 15 billion light years away (15 BILLION YEARS OLD) and show what we see today.
Please note that WINSTON works for the Ministry of Truth, and should not always be taken seriously (please note that he sometimes presents some great insights, so don't simply discount him). In this case the galaxies in the images are NOT 15 billion years old, and are NOT from a time when the universe was ten thousand times as hot and dense as it is today.

They are quite far away, and from a time when the universe was hotter and denser. However, dense as it may have been, in an earth based laboratory, any researcher would be proud to create a vacuum as good as the one between those galaxies.

mas_to
2005-Apr-13, 04:53 AM
anton, if you say it not 15 billion years please mention the true age (of course I believed it is not). and may be some link to support the fact

thanks, just want to know the truth

imported_WINSTON
2005-Apr-13, 08:51 AM
MINISTRY:

Action:
37

Location:
NASA Picture of the day archive

URL:
http://antwrp.gsfc.nasa.gov/apod/ap980607.html

Removed:
Previous references to distance( 15 billion LY's).

Link disabled:
Humanities most distant(which should tell you the distance)

Replacement:
Stock explanation with no reference to distance.

End Action

Nereid
2005-Apr-13, 10:21 PM
This may have been mentioned before, so apologies if I'm being repetitious ...

Here (http://arxiv.org/abs/gr-qc/0503107) is a good, recent review article on the current 'state of play' of cosmology, as a science. In parts, the math is heavy, and there are references to approaches and techniques that have been very successful in other parts of physics that a reader without a university-level background in physics may miss, but overall I think it a very good read.

In particular, it outlines the challenges anyone who wishes to develop an alternative faces - how to get a similar degree of consistency across so many independent sets of observations? It also illustrates the strengths (and weaknesses) of the 'dark energy' and 'dark matter' views, and the limits to how 'zero point energy' could make all the weirdness 'go away' (at least, within the framework of 21st century physics).

There is also an extensive list of references, for anyone wanting to follow up on any particular aspect.

Nereid
2005-Apr-13, 10:58 PM
Originally posted by mas_to@Mar 30 2005, 09:35 AM
hi,
if the most distant light we see is emitted by some thing 13.7 b ly away and big bang theory is true, is those object had some age too. I mean they must travel for some time to get there (assume that we are at the central of universe) and universe must be older than 13.7 b ly
or I got wrong in understanding that "WMAP" thing
1) the 'most distant light we see' is the CMBR, which was emitted ~300k years after the BB
2) the CMBR is not an 'object', it is the 'fossil light' from the last scattering of photons from baryons at the time (baryonic) matter and radiation decoupled; as far as we know, there were no 'condensed objects' at this time
3) yes; the universe is indeed older than the 'oldest light' that we see! :D

Nereid
2005-Apr-14, 12:07 AM
yes i agree , but what about the evolution of stars as well ,we have found that some stars to today can last 10's of billions of years , while others may only have millions of years to live ;and that there are so many different sorts ,how did we get to this state of evolution in only 13.7 billion years ( in universal terms ,in the life and death of a universe 13.7 billion years isn't very long) what makes us so sure we have our timing of the birth right?
Whew! Quite a lot of good questions here!

The oldest stars we have found are approx 13 bn years' old; the oldest structures we have observed in the early universe are approx 13 bn years' old. Our theories of stellar evolution match what we observe about stars - their luminosities, their 'metalicities' (the abundance of elements heavier than He), their masses, etc; our theories of galaxy evolution are very young, and our good observational data on 'young' galaxies rather limited ... many open questions in these areas!

However, the age of the universe is only mildly contrained by our theories of stellar evolution and galaxy evolution; far more 'demanding' are our theories of cosmology - and they are consistent with an age of approx 13.7 bn years.

,when we are still seeing galaxys 13.4 years ago ?
I don't think so; the details of what objects comprised the universe, in the ~billion years or so after (baryonic) matter and radiation decoupled are poorly known today ... check back in 20 years' or so!

some things don't add up do they !!!
Isn't that great?! If they did, would there be anything for astrophysicists, cosmologists, high energy physicists, etc left to do?

this is why I am interested to see if these early? galaxys hold different stars like the ones today !!!!!
So, how would you tell if they did (or didn't)?

also how long does it take a black hole to form a galaxy ?
or the other way round? If you're good, you might get time on a leading observatory or three, to test your ideas on exactly this question!

how do galaxys form ? do black holes create galaxys ? if they do how ?
Ditto!

( ie rub two black hole's together do you get star formation ???) or do black hole's use dark matter as a base to form a new galaxy ?
Well, one part of this is easy - if you 'rub two black holes together', you get a more massive black hole (and probably a whole lot of intense, transient gammas).

mas_to
2005-Apr-14, 02:50 AM
thanks nereid, thats explain alot.
another question, sorry if this bored you. Is this photon came from edge of the U or its had been travel to some place then bend/reflect/other to came to us.

Guest
2005-Apr-14, 05:00 PM
you can tell if these early galaxies held different stars like the one's today by observation and comparsion (like you say the principles of weight,heat,size,chemical elements etc are all very well-known) by comparing these stars to key one's (like the sun) where we know the age etc , we can at least know how old the galaxy isn't ,,, ie our sun is say 3.5 billion years old if we see a star just like the sun in these early galaxies then we can deduct from this that this galaxy must be over 3.5 billion years old,,,,,,,, but you are saying that there arn't any stars over the age of 13 by's or any galaxy's either , this is why we must at least check, to prove this is right and keep on checking!!!!!,,,do you have any picture's that show past these early galaxies ? that show no stars ,in the early stage of the big bang?

antoniseb
2005-Apr-14, 06:17 PM
Originally posted by Guest@Apr 14 2005, 05:00 PM
do you have any picture's that show past these early galaxies ? that show no stars ,in the early stage of the big bang?
We do not yet have pictures of early galaxies before stars. We might have such images in about 20 years or so. The SKA (Square Kilometer Array) is a large array of radio telescopes that will be built in about ten years, and one of the goals of this project is to map the formation of the clouds of gas that eventually formed galaxies and stars.

Please not that the images we have of very early galaxies are not very good. Those galaxies have had their light red-shifted very severely, and are too small and dim for our telescopes to see clearly. The James Webb Space Telescope will make some progress toward imaging these objects, but even that instrument will not resolve stars in those galaxies.

Nereid
2005-Apr-15, 01:07 AM
This recent Gemini result (http://www.gemini.edu/index.php?option=content&task=view&id=125) gives a flavour of the research currently being done ... not really about the earliest galaxies, more about galaxy evolution, esp in the [0.2, 1] redshift region.

Is this photon came from edge of the U or its had been travel to some place then bend/reflect/other to came to us.
Photons we see as the 'cosmic microwave background radiation' indeed have come to us from far, far away and long, long ago. On their journey they will have been through many gravitational wells - being blueshifted then redshifted ... this is the Integrated Sachs-Wolfe effect (http://astro.uchicago.edu/~laroque/ISW.html).

Observationally, the challenge is to sort the wheat (photons from the surface of last scattering) from the chaff (photons in the same wavelength range, but originating with other processes, e.g. synchrotron radiation, warm dust).

Guest
2005-Apr-15, 08:41 AM
[QUOTThe oldest stars we have found are approx 13 bn years' oldE]


what are the chances of any star reaching its projected age in a universe ,like our's , that is so full of danger and violence ? its a bit like looking for a needle in a haystack?

Nereid
2005-Apr-15, 12:50 PM
Originally posted by Guest@Apr 15 2005, 08:41 AM
[QUOTThe oldest stars we have found are approx 13 bn years' oldE]


what are the chances of any star reaching its projected age in a universe ,like our's , that is so full of danger and violence ? its a bit like looking for a needle in a haystack?
Except near the SMBHs at the core of galaxies, in binaries, and for some unlucky stars in dense globular clusters, almost all stars will live their lives in peace and die of ripe old age :D

wstevenbrown
2005-Apr-15, 06:10 PM
You're so right! Like humans, most stars lead boring, uneventful lives. When we watch cops-and-robbers, cloak-and-dagger, and cowboy flicks, we concentrate our attention on the extreme and the unusual, the sort of thing that makes the nightly news. Those of us who monitor extreme phenomena need to remind ourselves constantly of our willingly-imposed selection bias. "Red Dwarf Celebrates 13,700,301,217th Birthday-- Candles Brighter Than Star" is not headline news. ;) Steve

imported_WINSTON
2005-Apr-16, 07:24 AM
Ignoring observational science and it's interpretations/misinterpretations, a philosopher would tell you that the Universe has always been here because you cannot create something from nothing.

Nereid
2005-Apr-16, 02:58 PM
a philosopher would tell you that [...] you cannot create something from nothing
And if you ask this philosopher what "nothing" is .... :P

imported_WINSTON
2005-Apr-16, 06:25 PM
if you ask this philosopher what "nothing" is

Nothing is the absence of anything.

A finite age of the U implies a "nothing" existing before.......

I don't believe that people really can't understand what "nothing" means.

The Mayans developed the concept of zero long ago.

TO POINT: AGE OF THE UNIVERSE

If [According to BB theory] the Universe was a "singularity"
before the "bang", then it existed for Infinity until that point. There wasn't a "nothing".

The Universe would then be INFINITE in age.

If you say time didn't exist before the beginning, you are merely suspending the laws of physics for an epoch or area. This is not the scientific method at work. You could never describe a transition of "no time" to "time" that didn't take an infinity to happen (imagine an asymptetic line and extend it, as in the Nerds movie!)

Contrarily, the Catholics, who accept the BB theory, believe that nothing existed, then, in the beginning,{SUPERGUY} created the heaven and Earth.

The Bible places the age of the Universe at 6000 plus years. This is according to the church as investigated by an Archibishop who's name I can't remember, and noone would read the link if I gave one.

Mr. Smartypants gamer guy
2005-Apr-16, 07:07 PM
i dout well ever find out...sadly....becasue we'd have 2 find so many veriables it's just near imposible. and im speeking for now and in the future...

Nereid
2005-Apr-16, 08:50 PM
I'm sure we don't want this to become a philosophical discussion, but I can't resist ...
If
Nothing is the absence of anything.then surely 'nothing' can't exist! and 'nothing' could ever have existed!!

A finite age of the U implies a "nothing" existing before.......
Possibly. Or maybe it implies that 'before' is a poorly understood concept? or that 'exist' is more subtle than we intuitively feel?

I don't believe that people really can't understand what "nothing" means.
And I don't believe that people really CAN understand what "nothing" means ... so on what basis can we proceed (other than agree to disagree)?

The Mayans developed the concept of zero long ago.
Perhaps they did; what has 'zero' got to do with 'nothing'?

TO POINT: AGE OF THE UNIVERSE

If [According to BB theory] the Universe was a "singularity"
before the "bang", then it existed for Infinity until that point. There wasn't a "nothing".
Hmm, would you mind giving me a reference to a paper in which the BBT says 'the Universe was a "singularity" before the "bang"'? As far as I know, the concordance model in cosmology is quite clear that its domain of applicability does NOT extend to 'before' the first Planck second (~10^-43 s). IOW, to fault the BBT because it doesn't address 'time before the first Planck second' is like saying chemistry is useless because it doesn't say anything about quark-gluon plasmas.

[...] If you say time didn't exist before the beginning, you are merely suspending the laws of physics for an epoch or area.
This may seem a pedantic quibble, but it's actually rather deep - first, 'laws of physics' is an anachronism; the best you can do in physics (or any science) is a 'theory', and they all come with a 'domain of applicability'; second, 'before the beginning' is drenched in theory, it is most certainly NOT meaningful WITHOUT a theory (why? try constructing a definition of 'time' that is independent of 'reality'!)

This is not the scientific method at work. You could never describe a transition of "no time" to "time" that didn't take an infinity to happen (imagine an asymptetic line and extend it, as in the Nerds movie!)Au contraire, mon ami! Please don't take this as a personal criticism, but it seems the concept of 'science' that you are working with is one that may have been OK 150 years ago, but since Popper, Kuhn, Lakatos, etc, it's clearly not one which scientists themselves actually use (nor which philosophers of science use).

Contrarily, the Catholics, who accept the BB theory, believe that nothing existed, then, in the beginning,{SUPERGUY} created the heaven and Earth.
That's nice; but what has this got to do with science?

The Bible places the age of the Universe at 6000 plus years. This is according to the church as investigated by an Archibishop who's name I can't remember, and noone would read the link if I gave one.
Bishop Usher (http://dictionary.reference.com/search?q=usher)?

imported_WINSTON
2005-Apr-17, 02:44 AM
This is Q & A

The question was, "how old is the Universe"?

I was trying to give answers that were complete, taking into account the applicable variables involved [if this, then that].

You believe "nothing" has some esoteric meaning beyond the obvious. What is it?

If you can't put it in words then you don't know what you are talking about.


That's nice; but what has this [religion]got to do with science?

I was trying to cover all IFs. Forum notwisthstanding, if you are R it is not separable from science. Science is the explanation of all, R is the subset.


Hmm, would you mind giving me a reference to a paper in which the BBT says 'the Universe was a "singularity" before the "bang"'?

You say the singularity was "during the bang" or "after the "bang"? That doesn't even make sense.

Perhaps there's a mysterious fourth time reference for it: The singularity didn't happen before, during, or after the bang. If you have to create another exception, feel free.


'nothing' could ever have existed!!

There wasn't a "nothing".


You agree with me on this, you just don't follow my explanation.

damienpaul
2005-Apr-17, 03:13 AM
folks, religion is banned from the forum....

rudeyd
2005-Apr-17, 04:30 AM
What if the universe we are seeing at 13.6 billion years ago is only the "horizon" of the visible universe? Theoretically we would never be able to view beyond the horizon and that would really change the age and what little we think we know of the universe. What is the defining factor in determining the edge of time and the universe? What was here before the big bang anyway? Something had to have existed for it to have happened in the first place.

imported_WINSTON
2005-Apr-17, 04:35 AM
Something had to have existed for it to have happened in the first place.

I wish I had simply said that......

Guest
2005-Apr-17, 08:13 AM
I think therefore I am !!!!

its the thought that counts?



so much like the big bang would you say?


how much comes from thinking first,,,,,, !!!!!

Nereid
2005-Apr-17, 10:29 PM
Originally posted by Nereid
Hmm, would you mind giving me a reference to a paper in which the BBT says 'the Universe was a "singularity" before the "bang"'?
You say the singularity was "during the bang" or "after the "bang"? That doesn't even make sense.

Perhaps there's a mysterious fourth time reference for it: The singularity didn't happen before, during, or after the bang. If you have to create another exception, feel free.
It's actually much simpler WINSTON, 'big bang' is a term coined by Fred Hoyle, who was one of the authors of a different cosmological theory, called the Steady State Theory. He used the word as a pejorative, to indicate his disdain with the (intuitively, to him) ridiculous nature of this theory ... much to his chagrin, the name stuck!

If you care to read some of the published papers on the BBT, you will see that there is no proposal for what 'happened' in the universe, before the (co-moving) time of ~10^-43 s ... no singularity, no 'during the bang', no 'mysterious fourth time reference', ... So, to repeat, to criticise the BBT for having a 'singularity' and not 'accounting for the universe before t = 0' is like criticising Newton's theory of gravity for not accounting for how the AIDS virus crossed from some other primate species to Homo sap.

You agree with me on this, you just don't follow my explanation.OK, so please elaborate :D

SIDEBAR>>>>>>>>

Why are you and antoni so disagreeable? It's the big bang thing, isn't it?

You feel a need to retaliate, so you blast everything I say. Here at Q & A, you focus on ME. I didn't even ask the Q.
I can't speak for 'antoni', but when I see misrepresentation piled upon misunderstanding added to imprecision etc, I see red (Yes your honour, I'm guilty as charged - a pedant, a stickler for accuracy, and ignorance and wooliness as to what science actually IS a hot button).

My Universal particle theory is MORE in accordance with HIGGS than current model, within the laws of physics. I give correct predictions. I give detailed explanations of observations which are not well explained by current theory.
My bad; I hadn't read your post in AT until earlier today ...

Nereid
2005-Apr-17, 10:35 PM
What if the universe we are seeing at 13.6 billion years ago is only the "horizon" of the visible universe?
Good question!

Theoretically we would never be able to view beyond the horizonthat depends on your theory, doesn't it?
and that would really change the age and what little we think we know of the universe.why? Surely this would only be so within certain classes of theories? IF there were other theories - fully consistent with all good observational and experimental results - in which the 'age of the universe' remained unchanged, irrespective of how much of it were 'beyond the horizon', what basis would have for making a claim such as this?

What is the defining factor in determining the edge of time and the universe?
A ) the sensitivity, wavelength band of observations, type of 'signal' being detected, etc
B ) the theory within which the good observations are interpreted.

What was here before the big bang anyway?
Who knows? How could you find out?

Something had to have existed for it to have happened in the first place.
Other than some warm, comforting philosophical 'intuition', why?

mas_to
2005-Apr-18, 02:47 AM
well before we answer this age question, we had to agreed definition of age (definition is an important thing before debunk). I ask someone "how old are you" then he answer "27" is this right? he WAS born 27 years ago. but in different view we had to add 9 month in mothers womb, and we add 1 month to ovum creation. in extreme view particle that build his body is as old as universe.
so I think 13.7 bly is the U age from first planck time as nereid kindly explained (acording to BB theory, others as far as I know don't give age)

man from kibish
2005-Apr-18, 10:23 AM
Originally posted by Nereid@Apr 17 2005, 10:35 PM

Something had to have existed for it to have happened in the first place.

Other than some warm, comforting philosophical 'intuition', why?
Hello Neried,

In Physics we have an endless list of of WHY phenomenon happen; e.g why a Star goes nova; why a massive collapsing star becomes a 'black hole' or neutron star or white dwarf etc etc. A term coined often is 'a limit' has been reached or exceeded.

In the case of the big bang why don't we have a limit-that-has-been-exceeded (the cause) for the big bang (effect) to take off? What is the teaching here?

with respect,
Stephen - man from kibish

rambo07
2005-Apr-18, 11:31 AM
so far as proving the age of the universe the big bang theorist's have 3 main facts,,,,

1. no galaxy as yet has been over 13 billion light years away
2. no star has been seen over 13 billion years old
3. they have a picture of the back ground-radiation presupposing to be a leftover from the big bang!!!!


my argument is that until (in 20years time it has been claimed)we have strong enough telescopes we really can't prove the first two and number 3 has always been up for interpretation along with quark's which after many decades of searching down mine shaft's we still havn't found ?

I think its a bit presumptuous of one section of the scientific community not only to hog to an idea which changes in the wind as often as we find new data to suit its own needs but to hold on to most of the funding also , my only hope is that it will take sooner rather than later to prove them wrong (its a pity about the hubble , why cant we fund for a better replacement in space?)