Big Bang

[leftrightleftrightleft]

Space itself can move faster than the speed of light.

As far as I know, the rate of expansion is about 80 km/s/Mpc. Where 1 Mpc = 3.26 million light years. So even if the quasar was 12 billion light years away (12 billion years ago), it would be moving away from us at 98% the speed of light. And it doesn't seem to be any coincidence that we can't see anything beyond 12 billion light years because that would imply that the object is moving away from us faster than the speed of light according to the commonly accepted rate of expansion. Still makes my head hurt

Also, I'm not sure if space itself can move faster than the speed of light because I'm not really sure how the statement "the velocity of space" even has any meaning. Space, as in a vacuum, can't have a velocity because it has to be relative to something and nothingness can't be relative to anything because its nothing.

Also one thing to keep in mind regarding the age of the universe is that the number 13.7 billion years is based on our "observable universe."

True. But the whole notion of the Big Bang is based on extrapolation into the past based on the expansion rate. So it seems that even if we discovered things farther away, they would just have to be moving away from us faster and we would still get roughly the same result.

 

[Wiccan_Child]

I'm not one to disagree with you very often but, based on books and textbooks I've read, it seems that its commonly accepted in the scientific community that the universe began as a singularity which then "became" the Big Bang which has led to the expansion as we observe it.

Like I said to Chesterton, it's a common misconception, but a misconception nonetheless.

"The Big Bang was the event which led to the formation of the universe, according to the prevailing cosmological theory of the universe's early development (known as the Big Bang theory or Big Bang model). According to the Big Bang model, the universe, originally in an extremely hot and dense state that expanded rapidly, has since cooled by expanding to the present diluted state, and continues to expand today" -good ol' Wikipedia (emphasis mine).

As far as I can tell, Wikipedia is corroborating my claim. It's not saying the Big Bang was the beginning of the universe, just a theory that describes an event that shaped (or formed) the universe.

It seems most physicists would say that the universe "began" 13.5 billion in the Big Bang rather than them saying the universe is expanding currently via the "process" of the Big Bang. The Big Bang, however accidental a term, seems to imply an event, not a process.

An event needn't be instantaneous. Besides, you're quibbling the semantics of an open encyclopaedia

I have many problems with this theory, as well as the notion of an expanding universe. Its not really based on evidence, it just based on my own thought experiments (like the "Strange Idea" which you replied to). For example, here's another one:

Lets say at T=0 you have a quasar which forms. This quasar starts emitting light.
Now, you have T=12 billion years. The light from this quasar now reaches Earth, and the light from the quasar is 12 billion years old.

But at T=12 billion years, where is the quasar and how far away is it from the Earth? Because the quasar formed at T=0, which was supposedly 12 billion years ago. So the light we see on Earth is light from T=0, not T=12 billion.

This seems to imply that, at T=12 billion, the quasar, (if it still exists, and if the universe is expanding) is much further from Earth now. But it cannot be further than 12 billion years away because that would contradict the notion of it moving faster than the speed of light.

It makes my head hurt, but I feel like there's a contradiction hiding in there somewhere.

The complication is in oversimplifying the speed limit of the universe. Bizarrely, space can expand at faster than the speed of light, without violating relativity. This occurred during an early phase of the Big Bang known as the Inflation period. It's no longer that fast, but there it is.

So, in your scenario, light has taken 12 billion years to traverse space and reach the Earth. Space has expanded, the quasar has moved, but that initial emmitted photon has, by hook or by crook, taken 12 billion years to get here. Which is fine and dandy; what's the problem?

 

[Wiccan_Child]

Everything I've read says time and space began with the Big Bang. Are going outside the evidence and imagining some pre-existent universe without time and space?

It's a common misconception, but it's still a misconception. The evidence tells us the universe has been expanding from a singularity for 13.5 billion years, no more, no less. We cannot infer that this singularity was the origin of the universe - but it proves to be such a popular idea that it's stuck in the public conciousness.

As Hawking says, if anything happened before the Big Bang (i.e., prior to 13.5 billion years ago), it is utterly meaningless to us - the singularity sort of resets matter, so any detailed structure 'before' the singularity is lost. In other words, the Big Bang may not have been the start of the universe, but it may as well have been.

Think about it: how could we deduce that the Big Bang was the start of the universe? What possible evidence would there be for this?

 

[Agonaces of Susa]

What possible evidence would there be for this?

Other than direct revelation from God or angels, there is no possible scientific evidence that could suggest the universe is expanding.

It is impossible to observe the cosmos as a whole to determine if it's expanding.

It is impossible to observe the edge of the universe; since space is a priori there is no edge of the universe.

The universe is infinite: "... the host of heaven cannot be numbered...." -- Jeremiah 33:22

Therefore the Big Bang myth is pure speculative metaphysics.

The Big Bang myth is based upon the so-called "Hubble Law" (Hubble never accepted it) which is a myth invented by a Roman Catholic priest.

"The chance that the [Big Bang] theory [sic] is right is now less than one in one hundred trillion." -- Eric J. Lerner, physicist, 1991

All observational astronomy contradicts the Big Bang myth.

"If you want to find evidence refuting Big Bang Theory [sic], just point a telescope at the sky!" -- Tom Van Flandern, astronomer, 1993

 

[Chesterton]

As Hawking says, if anything happened before the Big Bang (i.e., prior to 13.5 billion years ago), it is utterly meaningless to us - the singularity sort of resets matter, so any detailed structure 'before' the singularity is lost. In other words, the Big Bang may not have been the start of the universe, but it may as well have been.

I asked if you were going outside the evidence and imagining some pre-existent universe and it seems like you are.

Think about it: how could we deduce that the Big Bang was the start of the universe? What possible evidence would there be for this?

The evidences for the Bang theory, such as expansion, are evidence of a start aren't they?

But I'm not even sure how you're using the word "universe". Maybe I'm thinking circularly - I think of this universe as "this thing which started" (because evidence indicates it must have). But if I try to think of it another way, I'm just speculating outside the evidence, aren't I?

 

[sandwiches]

The evidences for the Bang theory, such as expansion, are evidence of a start aren't they?

Expansion is evidence of expansion and yes of a possible singularity or highly dense ball of matter and energy. However, this alone doesn't explain how the matter and energy got there. So, no, the Big Bang does not try to explain the origin of the universe, that is everything that exists, it tries to explain how the universe is how it is and behaves the way it does (ie. expansion, background radiation, etc.)

 

[Chesterton]

Expansion is evidence of expansion and yes of a possible singularity or highly dense ball of matter and energy. However, this alone doesn't explain how the matter and energy got there. So, no, the Big Bang does not try to explain the origin of the universe, that is everything that exists, it tries to explain how the universe is how it is and behaves the way it does (ie. expansion, background radiation, etc.)

Yeah I know. My only issue is what seems to me WC's hand-waving away of the idea of a "start". We know it's expanding. Looking backwards, it could not have been expanding forever, so it had to start expanding. He says it's a popular misconception, but everything I've ever heard or read from Hawking or anyone else says the start of this expansion = the start of this universe.

 

[Wiccan_Child]

I asked if you were going outside the evidence and imagining some pre-existent universe and it seems like you are.

The point is that whether there was or wasn't is irrelevant: the evidence we see today would be the same regardless of whether the Big Bang was the beginning of the universe or not. So, we may as well regard it as the beginning - but, properly, technically, we don't know that.

The evidences for the Bang theory, such as expansion, are evidence of a start aren't they?

Their evidence that the universe has been expanding for 13.5 billion years. Redshift and galactic recession velocities, for instance, demonstrate a dynamically expanding universe, which we can then 'reverse' to see how long the universe has been expanding for - and we get a value of 13.5 billion years.
But this evidence doesn't tell us if the universe actually began then, merely that it's been doing what it's currently doing for 13.5 billion years.

But I'm not even sure how you're using the word "universe". Maybe I'm thinking circularly - I think of this universe as "this thing which started" (because evidence indicates it must have). But if I try to think of it another way, I'm just speculating outside the evidence, aren't I?

I define the universe as this expanse of space that contains all matter and energy. There might be other expanses, there might not be.

Let me ask you a question. What if the universe didn't start? What if it is eternal, or circular, or otherwise didn't have a beginning, as counter-intutitive as that may sound? As per your definition of 'the universe', would that mean the universe doesn't actually exist, and we should come up with a new name for this big ball of spacetime where we live?

 

[freezerman2000]

But there's contradiction in your words. If this universe has been going on for 13.5 billion years, that means it started 13.5 billion years ago. From what I understand, the expansion is the beginning of the universe; the way you talk it sounds like the evidence indicates the expansion of some smaller universe into our bigger one. Do you consider the singularity a universe?

i would like to answer this as I see it.
The universe and the expansion are the result of the singularity exploding. Newton's law of motion (for every action, there is an equal and opposite reaction).
All of the base building blocks for the universe were contained in the singularity,but the higher elements were forged by those base elements binding together.
In a sense, the universe was there before the expansion, but not in the complex and variety of building blocks we know today.
Some scientists believe that white noise on analog TVs and radios is the fingerprint of leftover radiation from the initial expansion.

 

[Wiccan_Child]

i would like to answer this as I see it.
The universe and the expansion are the result of the singularity exploding. Newton's law of motion (for every action, there is an equal and opposite reaction).
All of the base building blocks for the universe were contained in the singularity,but the higher elements were forged by those base elements binding together.
In a sense, the universe was there before the expansion, but not in the complex and variety of building blocks we know today.
Some scientists believe that white noise on analog TVs and radios is the fingerprint of leftover radiation from the initial expansion.

Weeeell, nowadays its more white noise from other sources of radiowaves, but the Cosmic Microwave Background Radiation (CMBR) can certainly be faintly detected. But yea, good explanation

 

[freezerman2000]

Expansion is evidence of expansion and yes of a possible singularity or highly dense ball of matter and energy. However, this alone doesn't explain how the matter and energy got there. So, no, the Big Bang does not try to explain the origin of the universe, that is everything that exists, it tries to explain how the universe is how it is and behaves the way it does (ie. expansion, background radiation, etc.)

There is a theory that states-when the universe has grown to it's physical limit, it will begin "the big crunch"...gravity gone wild. the entire universe will compact itself into a singularity only to expand again,resulting in another "big bang".
In the other camp, it will continue to expand until it is no longer able to sustain itself, and become a dark place with no activity at all. Call it the "dark ages".
I prefer the "crunch" theory. Death and rebirth.

 

[Chesterton]

The point is that whether there was or wasn't is irrelevant: the evidence we see today would be the same regardless of whether the Big Bang was the beginning of the universe or not. So, we may as well regard it as the beginning - but, properly, technically, we don't know that.

But the evidence we see today would also be the same regardless of whether there is a God, or whether there are fairies in the garden. I'm trying to understand your willingness to consider non-evidenced things as possible when they tend to support your worldview as a materialist, while discounting non-evidenced things which tend not to support your worldview. On the surface, it looks like simple prejudice.

Their evidence that the universe has been expanding for 13.5 billion years. Redshift and galactic recession velocities, for instance, demonstrate a dynamically expanding universe, which we can then 'reverse' to see how long the universe has been expanding for - and we get a value of 13.5 billion years.
But this evidence doesn't tell us if the universe actually began then, merely that it's been doing what it's currently doing for 13.5 billion years.

You're saying the universe could have existed before it began expanding? Seems contradictory. In the below quote you say "I define the universe as this expanse..." (this expansion). The universe is as the universe does, no?

I define the universe as this expanse of space that contains all matter and energy. There might be other expanses, there might not be.

Let me ask you a question. What if the universe didn't start?

Well what if water is something more than just hydrogen and oxygen? What if humans are more than just animals? Entirely legitmate questions, but scientists seem to prefer dealing with the evidence they can see and measure, and the evidence says "start".

What if it is eternal, or circular, or otherwise didn't have a beginning, as counter-intutitive as that may sound? As per your definition of 'the universe', would that mean the universe doesn't actually exist, and we should come up with a new name for this big ball of spacetime where we live?

Don't substitute "counter-intuitive" for "counter-the-evidence". Show the evidence for eternality or circularity.

 

[Wiccan_Child]

But the evidence we see today would also be the same regardless of whether there is a God, or whether there are fairies in the garden. I'm trying to understand your willingness to consider non-evidenced things as possible when they tend to support your worldview as a materialist, while discounting non-evidenced things which tend not to support your worldview. On the surface, it looks like simple prejudice.

I disagree with your premise: a world with gods and/or fairies would look quite different to the world we see today. We've discussed this before, and I believe you don't agree with that (as a theist, how could you?), and since this isn't EC we can't really go into it all that much - but it seems to me that, if fairies exist in our gardens, we should have seen them by now. Absence of evidence is pretty much evidence of absence.
Pre-Big-Bang universes, on the other hand, wouldn't leave any evidence due to the 'clean wipe' that is the conjoining singularity - so whether the universe sprung into existence ex nihilo or is the result of a pre-Big-Bang event, the evidence would tell us the same thing.

You're saying the universe could have existed before it began expanding? Seems contradictory. In the below quote you say "I define the universe as this expanse..." (this expansion). The universe is as the universe does, no?

No. 'Expanse' doesn't mean 'thing that's expanding', it means 'large swathe of space'. Space exists; I think even we can agree to that. A large amount of continuous space exists. This region of space could reasonably be defined as 'the universe'. There may, therefore, be other regions of space not connected to ours, which could reasonably be defined as another universe.

Well what if water is something more than just hydrogen and oxygen? What if humans are more than just animals? Entirely legitmate questions, but scientists seem to prefer dealing with the evidence they can see and measure, and the evidence says "start".

What evidence, exactly?

Don't substitute "counter-intuitive" for "counter-the-evidence". Show the evidence for eternality or circularity.

I won't, because I never claimed there was any, or even that I believed in them. My point is that you're arbitrarily restricting what the universe could be. Ultimately, circularity is a valid possibility, yet your definition doesn't allow for it. If the universe is circular (and I'm not saying it is, or that there's evidence that it is, or that it makes sense to our brains), purely hypothetically, if the universe is circular... what does that mean for your definition? Would you change it? Would you say that we don't actually live in 'the universe', since it doesn't have a beginning, as per your definition?

I'm not postulating a genuine alternative, I'm trying to show you the holes in your definition.

 

[sandwiches]

Well what if water is something more than just hydrogen and oxygen? What if humans are more than just animals? Entirely legitmate questions, but scientists seem to prefer dealing with the evidence they can see and measure, and the evidence says "start".

So what if we're made of sugar, spice, and everything nice? What if?

Science is supposed to deal with what can be measured and observed. That is science. Are you saying you dislike what science limits itself to?

 

[jonmichael818]

Yeah I know. My only issue is what seems to me WC's hand-waving away of the idea of a "start". We know it's expanding. Looking backwards, it could not have been expanding forever, so it had to start expanding. He says it's a popular misconception, but everything I've ever heard or read from Hawking or anyone else says the start of this expansion = the start of this universe.

We simply do not know what took place before 10 to the -43 seconds after the so called big bang. To say anything about that is pure speculation, that includes whether there was a begining or not. Some people refer to the big bang as the begining because for all practical purposes it is, but in reality we simply cannot say anything about the very early universe.
Furthermore, to say that there was an absolute begining would imply that something came from nothing. That idea is nonsense, it is more practical to suggest that something has always existed, and that something evolves into and from an unknown number of universes, branes etc.

A great deal of modern theoretical physicists believe that the big bang is not the begining. This is a great BBC documentary on the subject: "What Happened Before the Big Bang"
[youtube]http://www.youtube.com/watch?v=_bGx3UB-Slg[/youtube]

 

[Chesterton]

We simply do not know what took place before 10 to the -43 seconds after the so called big bang. To say anything about that is pure speculation, that includes whether there was a begining or not.

How is the time measured then? 10[sup]-43[/sup] seconds from what?

 

[Wiccan_Child]

How is the time measured then? 10[sup]-43[/sup] seconds from what?

From the singularity.

 

[Chesterton]

From the singularity.

The singularity as an event, or as a thing?

 

[Wiccan_Child]

The singularity as an event, or as a thing?

The singularity as both: it is a spatial-temporal singularity (i.e., spacetime was infinitely compact), and a matter-energy singularity (i.e., matter and energy were infinitely dense).

 

[Chesterton]

The singularity as both: it is a spatial-temporal singularity (i.e., spacetime was infinitely compact), and a matter-energy singularity (i.e., matter and energy were infinitely dense).

Hope it doesn't seem like I'm bickering, but I really would like to know. How do you measure time from the start of something, and still say that there wasn't necessarily a start?