The big bang theory

Sort:
ck516

iused wrote:

ck516, what do aurora sound like?  I was intrigued by this a little while back but the best I could find was this,

http://www.northern-lights.no/english/what/sounds.shtml

I'm moving north so with any luck I should get to experience an aurora myself fairly soon.


 That's the only good one we could find too, there are a few other crappy ones. It's a shame it's not actually like that though. Still, I'd have never thought to have asked that!

chessman_calum

Wow that sounded pretty amazing!

chess4david

May i ask why you care so much wether he was cranky or not?

BoobyFisher8008

  The big bang theory, is not really a theory rather a misnomer of a hypothesis, the big bang "theory", has never been proven, and probably never will be proven. 

As per this comment from a member above:

"In my opinion there was no "bang".  The Universe has been here for an infinite time, and will be here for an infinite time. 

Okay, all, have fun with that one."

 

The universe was not here for an infinite time, that makes absolutely no sense at all.  Not to mention that using infinity as per say forever is not always the case, rather we use infinity for the majority of aspects to describe very large numbers that seem to not end, or take too much of our lifespan to draw up to.  The limit of the time of existance this universe has been around, I'm sure of, approaches a very very very very large number, but that limit does exist.  As for the universe recycling itself over and over again, and there being prior universes, or "parent" universes before our own universe was reborn?  Absolutely a possibility.

De-Lar

Sharukin wrote:

My problem withh infinity is quite simple, you can never reach it so you can never actually show that it exists. The example of counting only proves you can always find a bigger number it doesn't actually show us anything infinite. Now, I know infinity gets used as a limit in mathematics but that is just an invented infinity, one of many mathematical objects that has no real existence. One might as well use n, the smallest number that makes you boggle (anyone know where that comes from?) as a limit. For a view on infinity that does not accord with mainstream mathematics try "Ad Infinitum" by Brian Rotman. If someone tells me that something real and physical is infinite I ask for some evidence. It has never been forthcoming so far.


Sharukin, what you ask for is an unfair question.  You know it is an unfair question, you ask it to get your kicks.  To make it seem like you are "smart"

 

You say infinity in mathematics is just "invented", that it doesn't show us anything infinite? Yet can you deny that I can find the area under an infinite curve?  That I can find which equation reaches towards infinity faster (which is something else you denied earlier)?

BoobyFisher8008

Infinity in mathmatics only appears when an equation does not have a solution, also known as divergence, another paradox in life as these things are bound to show up in all the sciences....  Some equations obviously have a solution as you create closer to a bound of infinity, or -infinity, that is due to the fact that the equation is in regression.  Meaning it was already getting smaller and you may be summing an infinite amount of points in this equation.  Eventually limits allow us to eventually just narrow them down to a fairly accurate answer.  Therefore the term infinity in relation to mathmatics has a applicable purpose, not just a crazy hypothesis that someone sticks it in to make it sound jazzi, when in reality it is overplayed by  many people. 

De-Lar, a question for you in response to your reply to another:

"You say infinity in mathematics is just "invented", that it doesn't show us anything infinite? Yet can you deny that I can find the area under an infinite curve?  That I can find which equation reaches towards infinity faster (which is something else you denied earlier)?"

  If you are talking about suming the area under an infinite curve within a certain domain and range, however, if the curve is divergent, that is not the case which I'm sure you know.  If you tell me you can sum the area of a parabola that is upside down and is not restricted by any axis or coordinates and you told me you could tell me the area, I will tell you, wrong, the area would be infinite.  If we set conditions, obviously we can find the area under the curve, but that's kids play.

  As per distance in the universe going on for infintesanly, or however you spell that, wrong.   We do not know the distance and therefore our guesses are pointless.

chess4david

Surly you have to decide if you believe in the big bang before your approach this problem. The big bang is crucial to the way you would approach such a concept as the size of the universe. 

I don't know think i am going to phrase this in the best way but I will try. If the universe has always been here as it is then you would have to have a recycling process for the formation of stars etc. If the universe has a start like the big bang then it is acceptable that one day every star will eventually cease to be and that there will be no light in the universe etc. If the universe has always been here then you have to have a way to continuously recollect matter after supernova etc for the continuation of the universe, as the universe would have to sustain its self. The universe would always be and have no end or start. I know this is a really odd way to address the idea of the big bang but as I can see no 'recycling processes' logically occurring I would be drawn to the idea that the universe had a start point for every thing to progress from, and an eventual effective end point were you have no light etc.

   As I fail to see the universe lasting infinitely from now and having existed infinitely up to this point exactly as it is, I fall in the big bang argument group. I would say thus that people who accept the big bang would say the maximum diameter of the universe is 2 x c x time since big bang. 

   No one knows the time since the big bang but at-least this concept shows the universe isn't of infinite diameter. 

iused

iused said "By sticking to his theory despite evidence to the contrary, Arp has placed himself outside of mainstream science."

zug said "of course by sticking to his theory Arp is outside mainstream astronomical points of view. That in itself is not a bad thing."

Sure, sticking to a theory against the tide of opinion is not a bad thing. You have to defend it with evidence, and sure, he does this too. However, his ideas are so radically different to what we already understand about physics and cosmology that his evidence is not strong enough. He disagrees with the idea that redshift is caused by recessional velocity and claims that there is no relation between redshift and distance. He argues instead that reshift is intrinsic, and explains this by suggesting that particle masses are not constant but increase with time. This is an extraordinary theory and if true would be revolutionary. To gain ground his ideas need to be backed by a lot of very good evidence.


His evidence is observations of objects with different redshifts that seem to be linked. There are images of low redshift galaxies in close separation with high redshift quasars. Most astronomers would say that the quasars are way in the background. He disagrees and says that you can see luminous bridges connecting the two objects. I think this is highly interpretive. Yeah, you can sort of see them, but it looks like it could be optical effect. It's not enough to convince me to overturn the Hubble relationship, which is supported by so many independent observations. His other evidence is statistical, that you see more high redshift quasars in close separation to low redshift galaxies than you ought to by chance alone. He says that what we see is incredibley unlikely, the objects must be linked. Others, who have repeated his calculations, revise the number and say it's not so unlikely after all.


None of this is enough to call the man a crank. Actually I'm regretting that a bit. I'd rather argue about his theories than his character, and he has such a gentle face. What made me call him a crank, and what I called disparaging remarks were statements like this,

"Nevertheless astronomers have again added a huge amount of undetected substance to the universe to make it agree with properties of a disproved set of assumptions. This is called the accordance model but we could easily imagine another name for it."

"most scientists are trained to stop short of articulating the obvious"

"After 30 years of saying nothing comes out of black holes, Stephen Hawking now approaches the observations saying maybe a little leaks out."

"Since, as usual, none of the above authors reference the voluminous evidence that quasars are intrinsically redshifted objects ejected from lower redshifted galaxies, there is very little chance of conventional astronomy correcting a huge error in their fundamental assumptions."

OK, it's quite tame, but it's pervasive, and he seems to me to be implying that the reason his theories do not find favour among the majority of astronomers is that the astronomers are blinded by their attachment to conventional cosomology.

iused

Zug wrote:

And in saying that, he is absolutely correct.


You really think that? I think the reason the majority of astronomers dismiss his evidence is because it's not that good.

chessman_calum

Maybe the big bang is 'recycling' itself. Maybe there was just one starting point and it expoded. I am going to try and use an example to show my idea of the universe and it's 'creatings'. (I may explain this badly).

Many, many billions of years ago there was 'nothing' just a small 'something' the size of a pin head. This 'something' exploded into what we see today: stars, galaxies, planets etc...

Now the example i'm going to use is throwing a ball up into the air and it comes back down, right? Well my theory is a bit like that but with the whole universe. The centre (of which the 'explosion' happened) is like the person. The stars, planets and galaxies are like the ball and when the big bang happened it was like the person throwing the ball. So when the ball  reaches it's maximum height and starts to come down, it is like the stars, planets and galaxies reaching their peak distance from the centre and coming back down to the centre point of the pinhead.

This could be the recycling process. It bursts out (the big bang) reaches its peak distance from the centre and then comes back into the size of the pin head and it repeates itself over and over again.

Just my opinion. Sorry if you don't understand it.

chessman_calum

NGC 7603 has been described as "the most impressive case of a system of anomalous redshifts discovered so far", see the paper astro-ph/0401147 for a comprehensive description which is summarized here. The configuration and redshifts are as mapped on the right: two galaxies of different redshifts, connected by a luminous bridge,and where the bridge connects to each galaxy -- precisely exactly at each of the two points -- there is a higher-redshift object. By virtue of the luminous bridge and the perfect positions of the two faint objects, it is highly likely that these four objects are physically linked and sharing the same space -- standard cosmological model or no.

The point is that any scientific claim must be falsifiable. To hold that redshift is an absolute indicator of distance must be to allow standards of evidence which will overturn that position. NGC 7603 is evidence which meets that standard, and if it is not sufficient to overturn the standard model all on its own, it is strong enough to require addressing by the proponents of the standard model.

chessman_calum

Markarian 205 (Mrk 205) is object number 205 in a catalog compiled by theArmenian astronomer, Benik Markarian. These are galaxies withstrong ultraviolet emission; many of them active galaxies. It's usually classified as a Seyfert galaxy, one with a bright nucleus, or as a low-luminosity quasar.

chessman_calum

Galaxies are fascinating not only for what is visible, but for what is invisible. Grand spiral galaxy NGC 1232, captured in detail by one of the new Very Large Telescopes, is a good example. The visible is dominated by millions of bright stars and dark dust, caught up in a gravitational swirl of spiral arms rotating about the center. Open clusters containing bright blue stars can be seen sprinkled along these spiral arms, while dark lanes of dense interstellar dust can be seen sprinkled between them. Less visible, but detectable, are billions of dim normal stars and vast tracts of interstellar gas, together wielding such high mass that they dominate the dynamics of the inner galaxy. Invisible are even greater amounts of matter in a form we don't yet know - pervasive dark matter needed to explain the motions of the visible in the outer galaxy. What's out there?

chessman_calum

Hope I helped :)

iused

chessman calum, that's certainly a possibility. Another would be we throw the ball hard enough and just keeps on going. Whether or not it returns depends on how hard we throw it and and the strength of gravity pulling it back. The gravitational force in turn depends on the density of matter underneath us. We can reason that there is a critical density, where if it was any greater the force of gravity would be enough to return the ball, and if it was any less the ball would keep on going.

The same is true with the universe. There is a critical density, and if the actual density of the universe is less we get continuous expansion. If it is greater the expansion halts and the universe collapses back in on itself. Because of the way that mass shapes space, these are referred to as either an open universe for continuous expansion, or closed universe for eventual recollapse.

There is a third possibility, that the actual density of the universe is in fact the critical density. This gives rise to what is called a flat universe. Current observations suggest that the universe is in fact very close to being flat.

There is a problem for the Big Bang model here. If the early universe was a shade too dense, it would have recollapsed long ago. If it was a shade too rarefied then we would have been no areas of matter dense enough to form stars and galaxies. The early universe would have had to be very close to flat. It is very unlikely that this could happen just by chance, so cosmologists think that there must be some reason for a flat universe. This is called the flatness problem, and it is one of the motivations for inflationary theory.

I think what chess4david was referring to though was a universe that was not created in a Big Bang, but had been around, as is, pretty much forever. In this case we would need a mechanism for matter to be recycled in continuous star formation and star death. This is a pretty serious problem for static universes.

chess4david

Yes i meant that the universe was static. Basically the 1st and 2nd laws of thermodynamics make it very unlikely that the universe can self-sustain. 

Steady State theory to me just seems like a very foolish theory to follow. The big bang seems far more logical to me. Every one has their opinion! At the end of the day none of us know for sure

iused

Everyone has their opinion, but astronomy is a science and the point of science is to separate the correct opinions from the false ones by experiment and observation. It's OK to use arguments like 'this does or doesn't seem logical' to form your hypothesis, but it's the evidence that's key. Nature doesn't care how you feel about infinity or dark matter, or whether I think there was a big bang or not. It will keep doing it's thing, and being what it is. Forty years ago there was more support for non-big bang models, but the consensus of scientific opinion today is strongly in favour of the big-bang. This has arisen because of decades of experiments and observations. We can't know for sure, but we can be pretty certain that the universe is expanding and arose out of a big bang.

iused

NGC 7603 and Markarian 205 are both part of what have been called 'anomolous redshift systems'. Both appear to be interacting with other objects in close separation but with different redshifts. In each case there is a so called 'luminous bridge' of material which connects the object with its differently redshifted companion. In an earlier post I sugested incorrectly that this might be an optical effect. In fact the luminous bridge is physically there, the question is whether or not it physically connects the objects.

The prevailing opinion among professional astronomers is that these are coincidental alignments. Although they appear to be connected, one object is actually a long way behind the other. The galaxies in both cases are obviously disturbed (hence the luminous bridge), but this can be explained by previous interactions with other nearby objects. There is evidence to suggest that this is what has happened.

A big problem is that there is no convincing direct evidence of interaction. Instead the arguments presented in favour of interaction are statistical, i.e. "there is no way this could be a coincidental alignment, it's just too much of a coincidence." However, the odds calculated by different parties vary wildly. I think there is a further problem with this sort of argument because it is arguing that something is unusual after the fact. It reminds me of Feynman's license plate.

"You know, the most amazing thing happened to me tonight. I was coming here, on the way to the lecture, and I came in through the parking lot. And you won't believe what happened. I saw a car with the license plate ARW 357. Can you imagine? Of all the millions of license plates in the state, what was the chance that I would see that particular one tonight? Amazing!"

I don't think these two observations are good enough evidence to overturn the  big bang theory.

You're going to have to help me out with NGC 1232. What's wrong with it?

BILL_5666

From what I recall of redshift and/or blueshift it is all believed to be doppler in origin, (at least according to the standard model/big bang).  In this model there is no intrinsic redshift. 

In defense of redshift being used to determine that the vast majority of galaxies are moving away from us (ie. that the universe is expanding) it should be noted that much closer objects such as stars within the milky way are both redshifted and blueshifted if they are rotating. 

What does Arp have to say about this?

bbrout

Interesting. An anomoly or a few anomolies may bring BBT into question but is certainly not enough to dislodge it. If the galactic redshift is observed and checked and measured, etc., then we pretty well have to accept that it exists. The redshift in itself does not prove BBT, but if you are to dislodge this theory, you must explain some mechanism for its existence other than universal expansion. As far as we know, there are only a few ways to alter the frequency of light. Doppler, gravity, differing media and hitting something and bouncing off. That's about it.

An interesting question is, does it make any difference? Let's say the redshift could be dopplarian or gravitational in nature through some unknown mechanism that we can get into later. The question is, can we tell the difference? Would there be any way to detect if the redshift is from a doppler or gravitational effect? The answer is no. We get the same answer in both cases.

The background 3K radiation is either the left over temperature from some Big Bang, or it may just be the ambient local temperature of the universe. In either case, it's the local temperature.

The Big Bang theory is very popular. In modern astronomy it is difficult to find a lab big enough to do experiments on stars and gallaxies. So, often, we use consensus to figure things out or at least discuss them. BBT is a very popular theory. That doesn't mean it's right, it means it is popular and the most accepted theory. There are some holes in it which brings it into question. There are some supporting factors to it that helps make it popular and acceptable by the scientific community. There is absolutely nothing wrong with this situation. What becomes wrong is when some arbitrary authority takes precident over observation and rational deduction whether it supports BBT or does not.

The globs have always been the bug bear of BBT. Dark Matter is a way of getting rid of that problem. I personally don't think it is going to be substantiated, but time will tell. Another problem is the absence of inter-gallactic dust. Another is gallactic structure.

However, a steady-state model has major problems as well. It's what makes it fun.