The Origin of the Universe: Reexamining the Big Bang Theory

[Chronos]

Singularities only exist mathematically. There is no observational evidence black holes, or the big bang singularity, are infinitely dense. Theorists are currently leaning toward finite density. The Planck density is an attractive alternative to infinite density.

 

[employee #416]

what do you mean by a primeval atom (you cannot mean a normal atom)?

Primeval atom simply means the first atom. The big bang was theorized to be the explosion of the first atom to ever exist.

Space itself expanded (and still does!). So the point itself expanded to become our universe. So that point is everywhere!

There is no concrete evidence that space is expanding.

russ_watters, your ponits are being countered with great arguments. I'm leaning towards the side of them not existing now.

Since black holes can only be detected through their effects on surrounding objects, its unsurprising we haven't found any anywhere else but near other objects.

I think that is the point that bride is trying to make.

Pulsars and black holes are different and look different.

So, what visible characteristics of black holes make them differ from the visible characteristics of pulsars? I thought black holes were not visible, so how can they "look different" than pulsars. Unless, of course, you are referring to the outer region of the two.

 

[Chronos]

There is no concrete evidence that space is expanding.

That assertion is false.

russ_watters, your ponits are being countered with great arguments. I'm leaning towards the side of them not existing now.

There is overwhelming evidence his points are correct.

what visible characteristics of black holes make them differ from the visible characteristics of pulsars?

They are far more massive than a neutron star can possibly be.

I thought black holes were not visible, so how can they "look different" than pulsars. Unless, of course, you are referring to the outer region of the two.

In a number of ways.

 

[employee #416]

That assertion is false.

Vern explained that the universe could very well not be expanding. The evidence they have so far are not concrete. If so, can you provide me a link to where they are 100% sure the universe is expanding and provide valid evidence to back this claim up?

More massive objects do not mean they are visibly different. Black holes are very small. How are they visibly different just by being more massive? Black holes have not be observed directly. Only through indirect observations. So to say they are visually different from pulsars is inaccurate. Maybe they look the same, but they are much more compact?

What we see around black holes is what is happening through interactions at the event horizon. This is not the black hole itself.

Thanks to everyone for your replies. When I get done with my site, I'll provide link. I'll have a number of quotes from you...if that's ok?

 

[Chronos]

Vern explained that the universe could very well not be expanding. The evidence they have so far are not concrete. If so, can you provide me a link to where they are 100% sure the universe is expanding and provide valid evidence to back this claim up?

No one is 100% sure of anything. Most rational people fall back to the preponderance of evidence. Start here for the 'preponderance of evidence' that the universe is expanding.

http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/ExpandUni.html

 

[employee #416]

Chronos, that site attempts to explain how the universe is expanding. In another section of the site, it explains how gravity is able to cause light to shift frequencies. This seems to tie into what Vern said.

One argument is just as plausible as the other. One just takes a more logical approach.

Thanks for your input.

-employee #416

 

[russ_watters]

Chronos, that site attempts to explain how the universe is expanding. In another section of the site, it explains how gravity is able to cause light to shift frequencies. This seems to tie into what Vern said.

One argument is just as plausible as the other.

Actually, one argument isn't more plausible than the other. You are mixing two completely separate issues. There would have to be an absolutely enormous amount of intergalactic mass to account for the observed redshift - iirc, the intergalactic medium would need to be more dense than the average galaxy. Unless you are suggesting there are lots of black holes out there...

So, what visible characteristics of black holes make them differ from the visible characteristics of pulsars? I thought black holes were not visible, so how can they "look different" than pulsars.

Chronos already addressed this, but don't you see that you answered your own question? If they aren't directly visible (ie, they don't give off their own radiation), then they certainly look different than objects that do give off their own radiation.

What we see around black holes is what is happening through interactions at the event horizon. This is not the black hole itself.

Right, black holes have event horizons (and an enormous amount of mass) and that's how we know they are black holes - so what's the problem? Or are you suggesting that an object with an event horizon (the distinguishing characteristic of a black hole) could be something else? A flat bill, webbed feet, and feathers - ehhh, still could be an elephant, right (just a type we've never seen before)? Don't you see how absurd that is?

More massive objects do not mean they are visibly different. Black holes are very small. How are they visibly different just by being more massive?

Au contraire - since all stars are virtually entirely hydrogen, mass is the primary determining factor in the properties of stars. For starters, massive ones are hotter.

Black holes have not be observed directly. Only through indirect observations.

So what? There are lots of things in nature that can't be seen directly, yet we know exist (ever hear of an elecron?) If an unseen object with enormous mass is sucking matter from a nearby star, it can't be anything else but a black hole - there is no other viable explanation.

So to say they are visually different from pulsars is inaccurate. Maybe they look the same, but they are much more compact?

You can't think of any observable physical characteristics that might be different? We've already discussed several...

 

[Vern]

according to Halton Arp red shift is the production of matter and that the older, the lesser the red shift,just a perspective!

I haven't seen that paper of Halton Arp but I do remember some of his comments about problems with the Big Bang. If what Arp says in the quote above is true it may provide a way to test the red shift. Red shift due to doppler should have all frequencies shifted the same. Red shift due to Arp's assertion should be shifted less in the red frequencies than in the blue.

Does that sound right ?

Vern

 

[Lesuth]

How do we know the universe is expanding? On average, a point twice the distance from us is moving away from us at twice the speed, what does this suggest? (Do not assume we are the centre of the universe). The actual space between the two points is expanding. Twice as much space between two points = twice as much separation over time, appears as twice the speed to us.

Also, there's no reason to rule out the existence of black holes simply because YOU can't comprehend what it physically means. A black hole is simply matter sufficiently dense that its' escape velocity is greater than the speed of light and hence is not able to emit radiation. This does make it very difficult to observe directly, but does not mean it should be ruled out as an unreasonable proposition. It is logical to assume that such an object could exist provided an environment or process leading to the creation of such dense material exists in our universe. When we observe accretion discs in binary systems, the evidence suggests that the compact object involved may well be a small black hole in some cases. X-rays are a particularly effective method of exploring these systems as the compact object causes the matter in the accretion disc to reach enormous speeds and the resulting radiation emitted on impact is often in the X-ray band. The amount of energy being seen in some of these cases could only be explained by the presence of a black hole.
Other evidence for black holes includes (radio)active galaxies, do some reading.

There are several explanations for why we assume the universe to have finite age. If the universe is infinitely old, you would have to assume some radiation has been traveling for an infinite distance, why then do we see a limit on the the redshift values of radiation we detect. You could also read up on some explanations of Olber's Paradox; one conceivable explanation is that the age of the universe is finite. I know I've read some other better explanations to do with the Hubble constant and Euclidean n-space but the details escape me at the moment, I'm sure you could find some information on it through google.com if you were sufficiently interested.

 

[Vern]

How do we know the universe is expanding? On average, a point twice the distance from us is moving away from us at twice the speed, what does this suggest?

This suggests to me that the wave length of the light in increasing. We can assume that is due to the doppler effect, which you are doing. This assumption is by no means a certainty.

The bigbang theory was founded by a Catholic Priest who worked for Hubble as a mule driver. Hubble never really accepted the theory.

Keep on chuggin !

Vern

 

[Vern]

I should go on to state that Abbe Georges Lemaitre went on to become a well known physicist in his own right. His "The Primeval Atom" was the orign of the big bang theory.

Vern

 

[mapper]

This is a very interesting thread.

Ive always said to myself that the origin of the universe would be the first question I would ask if I were to meet an intelligent extra terrestrial life form. To hear what they theorize.

Some other thoughts. If the universe has always existed wouldn’t the light emitted from every star/galaxy etc.. make our night sky full bright? If the universe is expanding, what is it expanding into? Is it creating space/time as its expanding? If you could travel past the point of the expansion what would that look like or what would that be?

If the theory that our universe is also going to collapse on itself is also true, could that point be traveled past if its no longer expanding? What happens to light if at its boundary if space is collapsing back on itself? If the expanding and collapsing of the universe is true, how many times has this process occurred? How many times will it last?

Its kinda like my perpetual motion idea. But as someone said before in my thread about needing to work hard for energy output e=mc ². So each time the universe has expanded and collapsed on itself it must be losing something as it surely can't last forever. So there must be an end point to this all. Understanding all the possible ends, if there is one may also help us understand the possible beginning, if there was one.

 

[Vern]

An infinite universe wouldn't necessarily result in brightness everywhere. We observe in space that the wavelength of light increases with distance. This we know is true even though we may never be absolutely certain of the cause. This increase would damp out the brightness, just as we see that it does.

Keep on chuggin !

Vern

 

[Entropy]

How do we know the universe is expanding? On average, a point twice the distance from us is moving away from us at twice the speed, what does this suggest?

I don't really believe in an expanding universe, or atleast one that is accelerating outward and will continue to do for eternity.

It is possible that the red-shift isn't cause only (or maybe even at all) by the Doopler effect. There are other ways red-shifts can occur, such as gravitational red-shift.

Personally I think any serious speculations on the what the universe was like in near the beginning or will be like near the end is very bold. We know so little about what is happening in the cosmos that it would be stupid at this point in time to devote your life souly (or even a good portion of time) trying to proving a theory describing the beginning and end of the universe. With our current knowledge, making a hardcore theory about the universe would be like determaining the ultimate fate of all mankind after studying one person's life for one minute.

 

[mapper]

With our current knowledge, making a hardcore theory about the universe would be like determaining the ultimate fate of all mankind after studying one person's life for one minute.

Thats great!

 

[Locrian]

Gravitational red-shift as a source of the red shift was already examined in this thread. Do the math. It requires insane amounts of matter to cause the kind of red shift we observe. Suggesting that is the cause would mean we'd have to find vast amounts of matter.

Look for yourself. It simply isn't there.

What studies have you done to determine the amount of mass in the universe? What studies have you done on the redshift? Why, when matter is so clumped together, do the redshifts all reflect distances so smoothly? Do the math on how light will be shifted if traveling through a medium evenly dispersed with matter. Why doesen't it match what we observe? The idea that red-shifting is caused by gravity is a terrible, terrible, terrible predictor of observables. Why stick with it?

Do the math, do the experiments. You will see the idea is absurd.

 

[Vern]

Gravity is just one of the things that contribute to a red shift in aging light. There are many other things including that light might simply loose energy as it ages.

Humason's original data showed the universe's age was about 2 billion years. That didn't work for very long so they changed the Hubble constant to make it fit the 4 or 5 billion years needed to account for the age of the earth. Then that didn't work when better telescopes came along so they added an expansion period with arbitrary rules made up to fit the observations. It is about time now for another change to account for the 20 billion year old things we're beginning to observe.

They lost me when they changed Humason's original stuff.

Vern

 

[Locrian]

They lost me when they changed Humason's original stuff.
Vern

That's a shame, since distance measuring methods were absolutely atrocious at the time. Hubble's own work shows error in the area of a factor of 10 - I know, I've done experiments to determine Hubbles Constant. Have you?

Astrophysics had hardly any tools going for it in 1929. It is no wonder things have changed.

 

[Chronos]

That's science for you. The predicted size of the universe has been getting bigger and bigger since the ancient Egyptians [I think they were the ones] made the first official guess. As more and better data comes in, science changes. This is not the sole domain of cosmology, it is true in all fields of science. Now that the WMAP data has been crunched, the error factor in our calculations of when the universe became observable [transparent to light] has been greatly reduced. Furthermore, the fact that remote parts of the universe look greatly different than our neighborhood certainly implies some kind of evolutionary process has gone on over time, just like the fossil record on Earth shows life many millions of years ago was much different than life today. You would think an ageless, eternal universe would look much the same everywhere at all times. It does not. Most of us therefore conclude it probably had an initial state and that initial state was vastly different than what has followed.

Footnote: If redshift is a highly unreliable distance indicator, it is hard to explain why entire classes of really exotic things we see in the universe [e.g., quasars] have huge redshifts.

 

[Entropy]

Gravitational red-shift as a source of the red shift was already examined in this thread. Do the math. It requires insane amounts of matter to cause the kind of red shift we observe. Suggesting that is the cause would mean we'd have to find vast amounts of matter.

What the hell are you talking about? It hasn't been brought up in this thread until now. Show me the math/source that has calculated this result.

What studies have you done to determine the amount of mass in the universe? What studies have you done on the redshift?

Exactly, we don't know how much mass there is, so measuring the amount of gravitational red-shift is difficult. So we don't know if we can count out gravitational red-shift or not.

Why, when matter is so clumped together, do the redshifts all reflect distances so smoothly?

I'm pretty sure gravity doesn't reflect light.

 

[employee #416]

Humason's original data showed the universe's age was about 2 billion years. That didn't work for very long so they changed the Hubble constant to make it fit the 4 or 5 billion years needed to account for the age of the earth. Then that didn't work when better telescopes came along so they added an expansion period with arbitrary rules made up to fit the observations. It is about time now for another change to account for the 20 billion year old things we're beginning to observe.

Never knew science had to "change" stuff to fit their observations. Magnificent, Vern!.

Chronos already addressed this, but don't you see that you answered your own question? If they aren't directly visible (ie, they don't give off their own radiation), then they certainly look different than objects that do give off their own radiation.

You're missing the whole point. They CANNOT look different. Their is no visual observations of black holes directly. Their is no visual comparison of a black hole to other objects. You can say interactions with a black hole an dother objects are different, but you can not say a black hole is visually different than any other object.

Lesuth, thanks for the reiteration.

Right, black holes have event horizons (and an enormous amount of mass) and that's how we know they are black holes - so what's the problem?

You took my complete thought, turned it into a fragment, and then asked a question about the fragment. That's the problem. A collapsed neutron star is a black hole. They have the same mass. A super-massive neutron star that has not collapsed yet can be classified as a black hole. It may have an escape velocity of that greater than light. It may have a nice hefty volume, but this neutron star is considered a black hole just because light can not escape?

Your counter statement: A neutron star cannot be that massive, it's own gravity will cause it to condense into a black hole. Density is what differs a neutron star from a black hole, though they are the same exact objects.

Your platypus and elephant joke is getting old. Try a new one. It wasn't funny the first time.

 

[Locrian]

I'm pretty sure gravity doesn't reflect light.

You misread my post. Reflect. As in show, or suggest. If we see an even and symmetric red shift that relates to distance, and you are proposing that mass is causing this then clearly matter must be spread out evenly. It isn't.

Exactly, we don't know how much mass there is...

When I asked you what studies you had done, I wasn't being rhetorical. We can judge about how much matter is out there because it exerts a force on things around it. I've taken data concerning this; what data have you taken? What experiments have you done? I was asking to see how much work you had done on the problem.

Light leaving a gravitational field has it's light reduced in frequency. However, if you are suggesting an even distribution of matter (which you must) then you need to take into account the fact that the light is falling towards matter between us and the emitter. This would raise it's frequency. Since you are suggesting a net decrease in frequency, then when you integrate over the distribution of matter between us and the object, the only way to create this red shift is to suggest a gradient of matter that would be easily detectable.

Unfortunately it isn't there. Galaxies far away do not contain significantly more matter than ones close... and they would have to. But then, do you even believe in galaxies, thinking as you do that matter is spread evenly throughout the universe? Don't think for a second dark matter will make up for the difference, because most dark matter is located around galaxies.

This is a terrible theory that is not based in any mathematics and leads to contradictory conclusions at every turn.

 

[Chronos]

Never knew science had to "change" stuff to fit their observations. Magnificent, Vern!.

Happens all the time. Observation is how theory is validated. When observation contradicts theory, the theory must be modified or discarded. Note, however, that observation is not immune to fallability. Observational results must be confirmed before accepted as fact.

... you can not say a black hole is visually different than any other object.

Sure you can. A black hole does not emit any detectable radiation. A neutron star, like any other star, does.

...A super-massive neutron star that has not collapsed yet can be classified as a black hole. It may have an escape velocity of that greater than light. It may have a nice hefty volume, but this neutron star is considered a black hole just because light can not escape?

A neutron star must have a mass between about 1.4 and 2 solar masses. If less than that, it does not have enough gravity to overcome the electron degeneracy limit and can only collapse enough to form a white dwarf [a much different critter]. If more massive than that, but less massive than the neutron degeneracy limit [~2 solar masses], it cannot collapse enough to form a black hole, only down to a neutron star - which is not dense enough to prevent light from escaping.

 

[Vern]

But because of the low surface brightness of galaxies there were severe technical difficulties. Humason developed the technique and made most of the exposures and plate measurements. The velocities of 620 galaxies were measured, and the results, published 1956, still represent the majority of known values of radial velocities for normal galaxies.

Result of Google search.

According to these folks we're still using much of Humason's data.

Keep on chuggin !

Vern

 

[Entropy]

When I asked you what studies you had done, I wasn't being rhetorical. We can judge about how much matter is out there because it exerts a force on things around it. I've taken data concerning this; what data have you taken? What experiments have you done? I was asking to see how much work you had done on the problem.

Yeah, you already said that, show me some calculations, sources or something to back up you're claim. I just proposed a possiblity, you are looking to completely disprove a theory and you can't do that by just saying "you're wrong."

Light leaving a gravitational field has it's light reduced in frequency. However, if you are suggesting an even distribution of matter (which you must) then you need to take into account the fact that the light is falling towards matter between us and the emitter.

Don't forget that when light is emited from a star it has to work through a star's gravity well egro being red-shifted, and when we observe the light it is only blue-shifted by Earth's gravity, that is if you think the gravity of our and the other galaxies is negligible. Although it probably wouldn't be noticable for small or medium stars.

Unfortunately it isn't there. Galaxies far away do not contain significantly more matter than ones close... and they would have to. But then, do you even believe in galaxies, thinking as you do that matter is spread evenly throughout the universe? Don't think for a second dark matter will make up for the difference, because most dark matter is located around galaxies.

I don't think gravity would have to be evenly distributed, it just has to be near the source of the light.

 

[Chronos]

Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.

 

[Vern]

Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.

True as usual; Chronos, but I'm thinking of the gravitational bending of the path as light propagates space. I don't think that would add to zero because the bend direction remains.

Vern

 

[russ_watters]

Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.

Damn, how did I miss that one? Good post.

 

[Locrian]

Yeah, you already said that, show me some calculations, sources or something to back up you're claim. I just proposed a possiblity, you are looking to completely disprove a theory and you can't do that by just saying "you're wrong."

On the contrary, the burden of proof is on you. I'll humor you this time.

You are either suggesting that it is only the object playing the part, and therefore objects farther away are always heavier dependent upon the distance, or you are saying there is a matter gradient evenly distributed throughout the universe.

In the first case you'll be at a loss to explain the state of stars far away. There are visible galaxies very far away which, under your theory, should have huge amounts of extra mass. Yet they contain stars who are burning rather weakly. On top of that, their rotational inertia doesen't allow for the huge amount of mass you are trying to give them. If all stars in a galaxy are redshifted, then they must all be heavier. Significantly.

As you know the redshift due to gravity with an observer away from the source is

f' = f(1/(1 + P_e/c^2)) where P_e is the gravitational potential energy.

The gravitational potential energy involved will be the the integral of the gravitational field produced by the body from the point the light is emmitted to the point it is recieved.

\int GM/r^2dr from R_1 to R_2. We'll take R_2 to be at infinity to give you the greatest benefit of the doubt. Once you integrate and take the limit your formula will be:

f' = f(1/(1 + GM/Rc^2))

Now let's take a star whose lyman alpha line has been shifted from a frequency of 25x10^12 to 8.3x10^12 (both in units of inverse seconds), which is far from the greatest shift to be seen, though it is sizable. Use a standard Sun type star that there are plenty of in the universe for your radius and you'll find that to create this red shift

M = 4x10^35, which is 100,000 times as heavy as our sun.

So in other words, to make this case that gravity is causing red shift, you are going to have to explain how everything half way to the edge of our vision is 100,000 times as heavy as everything near to us, and yet are visibly the same types of stars and do not show 100,000 times as much angular momentum.

Good luck

I won't bother with the matter gradient since you don't seem to feel matter is distributed evenly... and it's obviously just as invalid a hypothesis.

 

[russ_watters]

You're missing the whole point. They CANNOT look different. Their is no visual observations of black holes directly. Their is no visual comparison of a black hole to other objects. You can say interactions with a black hole an dother objects are different, but you can not say a black hole is visually different than any other object.

We're going around in circles, but it really is quite simple: if you have a light bulb suspended from the ceiling in an otherwise dark room, you can't see it if its turned off. But if you bump your head on it, you know its there, even though you can't see it. Now turn the light bulb on. Visually, what is the difference?

You make it sound like the failure to see that a black hole is actually a pulsar is a failure in our ability to observe it. It isn't: we don't observe emissions because there are none to observe. I think you may be confusing the absence of data with actual data showing no emissions. There is a difference. 0 is different from 10 - zero does not imply the absence of data or the possibility that if you could find some data it would be 10.

A collapsed neutron star is a black hole. They have the same mass. A super-massive neutron star that has not collapsed yet can be classified as a black hole. It may have an escape velocity of that greater than light. It may have a nice hefty volume, but this neutron star is considered a black hole just because light can not escape?

Maybe you could do some math to prove that an uncollapsed neutron star could have an event horizon. Hawking calculated that a neutron star of any mass does not have sufficient density to have an event horizon.

Now its sounding to me like you just don't understand what a black hole is.