What do you think about the Big Bang?

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What do you think about the Big Bang?

Post by Ann » Sun Jun 06, 2010 4:50 pm

A few months ago, I listened to a lecture by a Swedish astrophysicist (a woman at that :wink: ). While her lecture didn't primarily deal with the Big Bang, she said, nevertheless, that she believed that inflation happened before the Big Bang. In her opinon, inflation was probably set off by a quantum fluctuation of some sort. Something created an imbalance, like a big steep "hill" or "hole" in whatever equilibrium had existed before inflation and the Big Bang. "Something" accelerated down this suddenly created "hill" or "hole". This acceleration down the "hill" was, the astrophysicist said, what set off inflation. Indeed, she said, the acceleration was the inflation.

After an instant, the "something" that had come thundering down the "hill" or "hole" suddenly reached "rock bottom". There was, as you can imagine, a terrific crash. During this crash a humongous amount of kinetic energy was transformed into other forms of energy - energy that would eventually turn into matter, to stars and planets and to us.

The "crash" as the speeding "something" hit "rock bottom" was the Big Bang, the astrophysicist said. Big Bang was the conversion of kinetic energy into other forms of energy that were produced as a result of the end of inflation.

Personally I thought this was a terrific explanation of the Big bang and inflation. These concepts have seemed extremely odd to me. I have been told that the Big Bang was an unexplained explosion that suddenly "blew up" a "balloon of space" that suddenly experienced a runaway growth as inflation suddenly set in. But this theory doesn't explain what caused either the Big bang or inflation.

The idea of a "runaway acceleration down a hill" and a "crash at rock bottom", followed by the conversion of kinetic energy into other forms of energy, makes things much clearer to me. So I like this idea of inflation and the Big Bang.

What do the rest of you think?

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Re: What do you think about the Big Bang?

Post by Chris Peterson » Sun Jun 06, 2010 5:45 pm

Ann wrote:A few months ago, I listened to a lecture by a Swedish astrophysicist (a woman at that :wink: ). While her lecture didn't primarily deal with the Big Bang, she said, nevertheless, that she believed that inflation happened before the Big Bang.
Are you sure that's what she said? If so, she is without doubt wrong. Why? Because "Big Bang" and "inflation" have well defined meanings, and by those the Big Bang itself defines the beginning of events. In any inflationary Big Bang cosmology there is no "before". And "inflation" refers specifically to conditions that happened after t=0.

If she was describing things that happened "before" the Big Bang, she should have been using very different terminology.
The idea of a "runaway acceleration down a hill" and a "crash at rock bottom", followed by the conversion of kinetic energy into other forms of energy, makes things much clearer to me. So I like this idea of inflation and the Big Bang.

What do the rest of you think?
To me, it sounds like so much other silly cosmology, that tries to divine some "cause" for things. To assess it better would require actually seeing some paper she has produced, which expresses things more scientifically.

My opinion is that the LCDM Big Bang model is doing an awful good job of explaining the Universe as we see it, and until somebody finds something seriously wrong with it, most of these alternate ideas are going to have hard sailing.
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Re: What do you think about the Big Bang?

Post by rstevenson » Sun Jun 06, 2010 11:22 pm

[disclaimer: I am not a physicist nor any other kind of cosmologist.]

My take on what I've read about the subject is that our math only describes what happened after the expansion began, and there is nothing sensible we can say (in English or Math) about what came before the point at which our math begins to make sense -- if that reasoning isn't too circular. Therefore, any talk of explosions or runaway acceleration down a hill or any other natural language way of describing how this universe may have begun is just metaphorical. And relatively harmless, as long as you don't take it too seriously.

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Re: What do you think about the Big Bang?

Post by Ann » Mon Jun 07, 2010 12:19 am

Chris said:
Are you sure that's what she said?
Well, she actually didn't say that she believed it - she stated it as if it was a fact. And since I was at the lecture, and since I was very surprised at her claim, I asked her if it was really true that inflation came before the Big Bang. She said yes, and she went on by saying that it was inflation which set off everything and that it was the Big Bang, the conversion of most of the energy from inflation, that provided the universe with the energy it needed to eventually build the stuff that is in it today.

The name of this astrophysicist is Cecilia Jarlskog, and here is a link to some of her publications: http://arxiv.org/find/hep-ph/1/au:+Jarl ... /0/all/0/1

A few months earlier I had listened to another lecture by another Swedish professor of astrophysics, Ulf Danielsson. He, too, said that inflation came before the Big Bang. I don't know if it is a Swedish thing to believe or say that. Anyway, here is a link to some of Ulf Danielsson's publications: http://adsabs.harvard.edu/cgi-bin/basic ... son%2C+Ulf

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Re: What do you think about the Big Bang?

Post by Ann » Mon Jun 07, 2010 12:22 am

Rob said:
My take on what I've read about the subject is that our math only describes what happened after the expansion began
Well, that's exactly it. Cecilia Jarlskog and Ulf Danielsson, two Swedish professors of astrophysics, both said at lectures where I was present that it was inflation that started the expansion of the universe.

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Re: What do you think about the Big Bang?

Post by rstevenson » Mon Jun 07, 2010 1:26 am

That extremely long URL for Danielsson's papers led me to one in particular, called Lectures on string theory and cosmology, in which it becomes confusingly (to me) clear that the word expansion and the word inflation mean different things, and neither seems to have anything to do with what I'm coming to believe is the ineptly named Big Bang. In short, it makes for interesting, if headache-inducing, reading.

Thanks Ann, I think.

Rob

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In case you were wondering where I'm at with this sort of thing, I'm about half-way through Harrison's "Cosmology" and have the three volume set of "The Feynman Lectures on Physics" staring balefully at me awaiting their turn. All because I've applied to study for a BSc in Astrophysics starting in September. (I have some catch-up work in Chemistry and Math to do this summer, so my acceptance is conditional. They want to be sure my old brain still works as well as it once did.)

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Re: What do you think about the Big Bang?

Post by alter-ego » Mon Jun 07, 2010 2:17 am

In case you haven't seen this, the graphic the summarizes the presently most accepted, state-of-the-art understanding of the Big Bang model, and what is known including the new, Dark Energy component. You can see that quantum fluctuations started the ball rolling (if there is a ball), and therefore defines "t=0". And if you heard branes mentioned, that is new, higher-dimensional, multi-universe type stuff. Way out there :ssmile:

http://antwrp.gsfc.nasa.gov/apod/ap060323.html

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Re: What do you think about the Big Bang?

Post by Chris Peterson » Mon Jun 07, 2010 2:25 am

Ann wrote:Well, she actually didn't say that she believed it - she stated it as if it was a fact.
Well, that's unfortunate. It is far from a fact; when dealing with cosmology, no scientist should state any broad theory as fact, since the entire area still contains much that is speculative.
And since I was at the lecture, and since I was very surprised at her claim, I asked her if it was really true that inflation came before the Big Bang. She said yes, and she went on by saying that it was inflation which set off everything and that it was the Big Bang, the conversion of most of the energy from inflation, that provided the universe with the energy it needed to eventually build the stuff that is in it today. The name of this astrophysicist is Cecilia Jarlskog...
Based on her publications, I'd call her a particle physicist, not an astrophysicist. Of course, there can be some overlap. In any case, none of her referenced publications remotely suggests she believes that inflation happened before the BB, or that this is even an area of professional interest. So my inclination is to largely disregard what she said at the lecture.
A few months earlier I had listened to another lecture by another Swedish professor of astrophysics, Ulf Danielsson. He, too, said that inflation came before the Big Bang.
His publications identify him as a cosmologist with a strong focus on string theory. There is nothing at all to suggest that he professionally considers inflation to have occurred before the BB. Quite the opposite- he is a proponent of an inflationary theory called chain inflation that attempts to resolve inflation in terms of string theory. This is still the standard inflation, which occurred after the BB, but driven by some sort of fast tunneling mechanism involving quantum fluctuations. So his professional record contradicts what he apparently said at the lecture. So again, I'll take the formal publications over whatever he might have had in mind in an informal setting.

I also think it is possible that you misunderstood these lectures, or the lecturers misunderstood your questions. By definition inflation must come after the Big Bang. But Danielsson, at least, is also a brane theorist, which means he is interested in what "caused" the Big Bang, and people who do work along those lines might describe scenarios a bit like what you initially described as occurring "before" the BB. So perhaps they were talking about some sort of expansion that triggered the BB, and not about inflation at all.
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Re: What do you think about the Big Bang?

Post by alter-ego » Mon Jun 07, 2010 2:52 am

Chris Peterson wrote: ... But Danielsson, at least, is also a brane theorist, which means he is interested in what "caused" the Big Bang, and people who do work along those lines might describe scenarios a bit like what you initially described as occurring "before" the BB. So perhaps they were talking about some sort of expansion that triggered the BB, and not about inflation at all.
One synopsis I read about brane theory explicitly stated that collisions between branes are triggers, if not the cause, for not only The Big Bang, but an endless cycle of them. Pretty deep theorizing, and at this point, looking for any visible evidence of brane collisions in our Universe (yes, I read of what signiture that might be) is beyond our current capabilities. Sorry, does not apply to brane theory. I mean talk about speculation up to my eyes (not just knee deep!); I wish I could fathom the theory details just so I could look at it as something more than talk.
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Re: What do you think about the Big Bang?

Post by Ann » Mon Jun 07, 2010 2:57 am

You're welcome, Rob. And thanks for your explanations and your input, Chris and alter-ego.

In hindsight, I realize that I should have asked Cecilia Jarlskog if inflation isn't necessary to smooth out the irregularities produced by the Big Bang, so that those major irregularities would have been there in the universe today if inflation hadn't happened after the Big Bang and taken care of them. But Cecilia Jarlskog's lecture was aimed at the general, if interested, public, and there were many people there who wanted to ask questions, many of which were (I think) much less interesting and much more irrelevant to her lecture than my question about the Big Bang. It didn't occur to me that I should have asked this follow-up question, and I may not have had the chance to ask it if I had tried. We were at a public library which was just about to close when the professor's lecture ended and we had the chance to ask questions.

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Re: What do you think about the Big Bang?

Post by Beyond » Tue Jun 08, 2010 8:53 pm

I think the Big Bang was really more like a really Big Whoosh. Inflation is close to understanding, when you have not yet discovered the cause.
Yes, 4 different kinds of energies came from the event. So did 4 different kinds of Earths, of which WE are in the 3rd one.
There are also other 4's and other things that came from and are involved with the Event called the Big Bang. However i cannot speak much about it in this website because much of what i would have to say falls out of the boundries that have been set up here and would also be greatly misunderstood due to preconceived ideas of what the meanings of some things are that have been misinterpreted from long ago.

There-fore I think the Swedish Scientists are as close as you can get by sticking to the standard Scientific investigations.
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Re: What do you think about the Big Bang?

Post by hstarbuck » Wed Jun 09, 2010 8:52 am

The standard model tells us how space, matter, and energy (not in order) in our universe came to be , from neutrinos and atoms to planets and galaxies, and is supported by evidence--the cosmic background radiation and redshift of galactic clusters for starters. It takes us back over 13 billion years to 10-43 seconds after the big bang, through inflation where it expanded faster than the speed of light 50 powers of ten in size from 10-37 s to 10-33 s. Finally, 380,000 years after t = 0 photons are able to fly freely after electrons are captured by the hydrogen and helium nuclei. So on and so forth. I don't know that we can ever know or need to know what happened before t = 0, if there was a before. What is important is that this most popular theory is taught to the masses so that we appreciate our place more and not think that the Earth or mankind is better than the rest of the universe. If a new theory is to replace the standard model then the evidence will have to speak for itself and then all reasonable physicists will jump on board. Same goes for plate tectonics or evolution through natural selection as other examples. Some people still think the Earth and the rest of the universe is a few thousand years old! I just find it weird that a scientist would tell people "how it is" with such a new and unpopular idea. I do believe that I am willing to change some views--or parts of them--if new evidence is brought forth to change my mind. On the other hand, there is nothing wrong with speculating about these mysterious topics such as multiverses, multidimensions, strings, branes, whatever, and if I could do the math (my calculus, linear algebra, and other math for physicists all seem to be fading nowadays) I may entertain them more.

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Re: What do you think about the Big Bang?

Post by Guest » Fri Jun 11, 2010 1:07 pm

By chance I noted this blogg conversation about inflation and the Big Bang referring to me.

Let me explain how to think about it.

Inflation is now a pretty standard part of cosmology. It corresponds to a phase of accelerated expansion. When it ends, the energy that drew inflation is converted into matter and energy (this is called reheating). This is what prepares the universe in the mysteriously homogenous state that was such a big problem for the old Big Bang theory.

The details of inflation has been discussed over the years, but the most popular scenario is the one of Linde.
OK, so, what should we call Big Bang? Well, one suggestion that I (and many others) think is the most natural is the moment when inflation ends. This is where the model match on to the standard Big Bang model and this is where all the matter and energy is created. This makes good pedagogical sense.

Another alternative would be to use it to refer to the moment when inflation started. The problem with this is that it is not at all clear that such a moment actually exists. A popular version of inflation (compatible with Linde) is eternal inflation where there is no beginning. So, the Big Bang would in this case correspond to a first moment even though we do not know such a moment existed. This is confusing.

So, it is not a matter of the content of the science but a matter of how to define the use of the words. If I want to draw a timeline of the universe (and not want to commit myself to the presence of a hypothetical beginning) I have a very difficult time to use any other definition than the one I propose. Furthermore, it also makes perfect historical sense given what inflation was set out to explain.

If we one day find that there IS a first moment we might reconsider the wording. But I would in that case suggest that one comes up with a new name for the beginning of inflation and time, and keep Big Bang for the end of inflation. Any suggestions of what to call it?

Ulf Danielsson

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Re: What do you think about the Big Bang?

Post by Chris Peterson » Fri Jun 11, 2010 2:06 pm

Guest wrote:So, it is not a matter of the content of the science but a matter of how to define the use of the words. If I want to draw a timeline of the universe (and not want to commit myself to the presence of a hypothetical beginning) I have a very difficult time to use any other definition than the one I propose. Furthermore, it also makes perfect historical sense given what inflation was set out to explain.

If we one day find that there IS a first moment we might reconsider the wording. But I would in that case suggest that one comes up with a new name for the beginning of inflation and time, and keep Big Bang for the end of inflation. Any suggestions of what to call it?
Hello Ulf-

Thank you for your explanation- that makes sense. I find myself caught up sometimes in the ambiguity of "Big Bang", since the term may be used synonymously with "t=0" or to describe a process early in the Universe, or even to describe a process that is still happening.

I'd opt for not using "Big Bang" to describe the end of inflation, but retain it in its broad sense of the class of theories that describe the Universe as expanding from a single "point" starting from a single "time". That is, I would use the term for the process, not any particular point in the process. Whether we need additional words is debatable; I think it is pretty clear simply referring to "t=0" or "the beginning of expansion" for the part before inflation, and "the end of the inflationary phase" for what came after. Your usage would make it possible to say "the Big Bang occurred after inflation", and that is going to be confusing to a lot of people (as evidenced by this particular discussion).
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Re: What do you think about the Big Bang?

Post by Ann » Fri Jun 11, 2010 4:35 pm

I said something, in my first post here, about "falling down a hill". Well, I was referring to what astronomers call a "vacuum".It looks something like this:

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I rather like the idea that the Big Bang started when "something" fell down a vacuum and started picking up kinetic energy. As that thing whatever it is reaches the "true vacuum", it is clearly going to release a lot of energy. I like the idea that something like this is the beginning of our universe.

Chris, you said that you preferred to use the term Big Bang in such a way that it referred to an entire process, not to a specific moment during that process. Does that mean that you are willing to think of inflation as part of the Big Bang?

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Re: What do you think about the Big Bang?

Post by Chris Peterson » Fri Jun 11, 2010 4:54 pm

Ann wrote:Chris, you said that you preferred to use the term Big Bang in such a way that it referred to an entire process, not to a specific moment during that process. Does that mean that you are willing to think of inflation as part of the Big Bang?
Of course. That is the standard viewpoint for the standard model. Nearly all cosmologists see it that way.
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Re: What do you think about the Big Bang?

Post by Ann » Sat Jun 12, 2010 10:22 am

Chris, you said that you preferred to use the term Big Bang in such a way that it referred to an entire process, not to a specific moment during that process. Does that mean that you are willing to think of inflation as part of the Big Bang?
Of course. That is the standard viewpoint for the standard model. Nearly all cosmologists see it that way.
But that is not how the Big Bang is described to the general public, not even to the astronomically interested general public. When you read astronomy magazines aimed at a readership of interested laymen, such as Sky &Telescope or Astronomy, you definitely get the impression that the Big Bang happened first and inflation happened afterwards. Therefore, I think it would be a good thing if people like you, Chris, might bear in mind that people in general might not know how comologists define "Big Bang". In other words, it might be a good thing if you expect that many people here might not to know what someone like yourself actually mean when you talk about Big Bang! Still, let me point out that we are lucky to have someone like you here to explain things to us. I'm just saying that many of us are not professional cosmologists, and we might benefit from having the term "Big Bang" defined to us more clearly.

When you protested when I said in my first post that inflation may have happened before the Big Bang, it wasn't absolutely clear to me that you think that there is no distinction between the Big Bang and inflation. Or maybe I misunderstood you again. Maybe you are saying that the Big Bang is the whole thing, and inflation is just a part of it.

If we define the term "inflation" not only as a part of the Big Bang but also as a runaway increase of the size of a universe which had, however, actually been born before it was inflated, do you have any thoughts on what might have caused this runaway expansion, Chris?

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Re: What do you think about the Big Bang?

Post by Chris Peterson » Sat Jun 12, 2010 3:02 pm

Ann wrote:
Chris, you said that you preferred to use the term Big Bang in such a way that it referred to an entire process, not to a specific moment during that process. Does that mean that you are willing to think of inflation as part of the Big Bang?
Of course. That is the standard viewpoint for the standard model. Nearly all cosmologists see it that way.
But that is not how the Big Bang is described to the general public, not even to the astronomically interested general public. When you read astronomy magazines aimed at a readership of interested laymen, such as Sky &Telescope or Astronomy, you definitely get the impression that the Big Bang happened first and inflation happened afterwards.
Because it did! You are missing my point, and Danielsson's as well: it's all a matter of terminology. Is "the Big Bang" what you call the instant of creation, or is it what you call the end of the inflationary phase, or is it what you call the entire formation process?

The Universe did not begin with inflation, and I don't think anybody is saying it did. First there was the initial expansion from a singularity or near-singularity. That is often called "the Big Bang", but the term is ambiguous. After that was the period of inflation. This ordering of events is not in question.
When you protested when I said in my first post that inflation may have happened before the Big Bang, it wasn't absolutely clear to me that you think that there is no distinction between the Big Bang and inflation. Or maybe I misunderstood you again. Maybe you are saying that the Big Bang is the whole thing, and inflation is just a part of it.
As I said to Ulf, the only issue is one of terminology. Saying that inflation happened before the Big Bang is extremely confusing to most people. I think it is reasonable to refer to the instant of creation as the Big Bang, or refer to the extended creation process as the Big Bang. I don't think it is reasonable to take one part of that process (inflation) and call that the Big Bang, or to identify a particular time (immediately after inflation) as the Big Bang.
If we define the term "inflation" not only as a part of the Big Bang but also as a runaway increase of the size of a universe which had, however, actually been born before it was inflated, do you have any thoughts on what might have caused this runaway expansion, Chris?
That is outside my area of expertise. Certainly, there are different theories describing inflation. These include ideas about vacuum energy, string theory ideas (like Ulf's), and others. While inflation itself is well accepted and is a key component of the most widely accepted models of cosmology, its underlying mechanism remains an area of active research.
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Re: What do you think about the Big Bang?

Post by Ann » Sat Jun 12, 2010 3:09 pm

Chris wrote:
Saying that inflation happened before the Big Bang is extremely confusing to most people. I think it is reasonable to refer to the instant of creation as the Big Bang, or refer to the extended creation process as the Big Bang. I don't think it is reasonable to take one part of that process (inflation) and call that the Big Bang, or to identify a particular time (immediately after inflation) as the Big Bang.
Okay, Chris. That is clear enough to me.

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UT: Astronomy Without A Telescope – Is Time Real?

Post by bystander » Sun Jun 13, 2010 1:06 am

I thought this was a timely post in Universe Today (12 June 2010)

Astronomy Without A Telescope – Is Time Real?
Universe Today | Steve Nerlich | 2010 Jun 12
The way that we deal with time is central to a major current schism in physics. Under classic Newtonian physics and also quantum mechanics – time is absolute, a universal metronome allowing you determine whether events occur simultaneously or in sequence. Under Einstein's physics, time is not absolute – simultaneity and sequence depend on who's looking. For Einstein, the speed of light (in a vacuum) is constant and time changes in whatever way is required to keep the speed of light constant from all frames of reference.

Under general relativity (GR) you are able to experience living for three score and ten years regardless of where you are or how fast you’re moving, but other folk might measure that duration quite differently. But even under GR, we need to consider whether time only has meaning for sub-light speed consciousnesses such as us. Were a photon to have consciousness, it may not experience time – and, from its perspective, would cross the apparent 100,000 light year diameter of the Milky Way in an instant. Of course, that gets you wondering whether space is real either. Hmm…

Quantum mechanics does (well, sometimes) require absolute time – most obviously in regards to quantum entanglement where determining the spin of one particle, determines the spin of its entangled partner instantaneously and simultaneously. Leaving aside the baffling conundrums imposed by this instantaneous action over a distance – the simultaneous nature of the event implies the existence of absolute time.

In one attempt to reconcile GR and quantum mechanics, time disappears altogether – from the Wheeler-DeWitt equation for quantum gravity – not that many regard this as a 100% successful attempt to reconcile GR and quantum mechanics. Nonetheless, this line of thinking highlights the ‘problem of time’ when trying to develop a Theory of Everything.
The winning entries for a 2008 essay competition on the nature of time run by the Fundamental Questions Institute could be roughly grouped into the themes "time is real", & "no, it isn’t" and "either way, it’s useful so you can cook dinner."

The "time isn't real" camp runs the line that time is just a by-product of what the universe does (anything from the Earth rotating to the transition of a Cesium atom – i.e. the things that we calibrate our clocks to).

'Time isn't real' proponents also refer to Boltzmann's attempt to trivialise the arrow of time by proposing that we just live in a local pocket of the universe where there has been a random downward fluctuation of entropy – so that the perceived forward arrow of time is just a result of the universe returning to equilibrium – being a state of higher entropy where it's very cold and most of the transient matter that we live our lives upon has evaporated. It is conceivable that another different type of fluctuation somewhere else might just as easily result in the arrow pointing the other way.

Nearly everyone agrees that time probably doesn't exist outside our Big Bang universe and the people who just want to get on and cook dinner suggest we might concede that space-time could be an emergent property of quantum mechanics. With that settled, we just need to rejig the math – over coffee maybe.

I was prompted to write this after reading a Scientific American June 2010 article, Time Is An Illusion by Craig Callender.

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Re: What do you think about the Big Bang?

Post by Beyond » Fri Jun 18, 2010 2:00 am

I see time as a measurement of rate of decay, which also seems to be how the Atomic clock works.
I see that before the "BIG Bang", everything was at rest and functioning smoothly. ((in a state of timelessness?))
Then at some point, for some reason, the stuff hit the fan and as "They" say - the rest is ITS Story.
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Re: What do you think about the Big Bang?

Post by wonderboy » Sun Jun 20, 2010 11:57 am

I know its a bit "alternate" but I still think the white hole theory rocks. It explains expansion (and acceleration) and also accounts for matter in OUR universe.


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Re: What do you think about the Big Bang?

Post by Beyond » Mon Jun 21, 2010 3:29 am

As to whether or not there was expansion before, during or after what is called the Big Bang -- I say yes to all 3. Think of it like a seed that fell into a very tiny crack in a very big boulder and sprouted. The roots go down into that very tiny crack and keep putting pressure on it until it gives way and cracks the boulder in two. That has actually happened and people were very surprised that a little seed had so much power in it.
Well it didn't when it started. It grew into the boulder and kept growing and growing until the boulder could not take the pressure anymore and split in two.
So i think the Universe started similarly. There was something there, very big, that was at rest. Something started to expand(grow)until the point was reached that what was there could no longer hold back what was growing and - WHOOSH -- expanding universe.
The Whoosh was likely faster at the start because of the built-up pressure, but would have quickly settled into the rate of expansion of whatever it was that was growing and caused it to go Whoosh in the first place.
Scientists have discovered that whatever it is that is causing the expansion is alive. Due to the fact that they have found that the expansion is actually increasing in speed after all this time, means that there is a living force that is driving the expansion. Only a living force can keep increasing.
The Question is -- what is that living force and what do you call it? and what - if anything - can you do with it?
Thats what i think about the Big Bang.
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Re: What do you think about the Big Bang?

Post by Chris Peterson » Mon Jun 21, 2010 3:52 am

beyond wrote:As to whether or not there was expansion before, during or after what is called the Big Bang -- I say yes to all 3.
To be clear, we aren't talking about "expansion", but about "inflation". There was no inflation before the BB for the simple reason that inflation is a phenomenon defined to begin after the Universe began.
Scientists have discovered that whatever it is that is causing the expansion is alive. Due to the fact that they have found that the expansion is actually increasing in speed after all this time, means that there is a living force that is driving the expansion. Only a living force can keep increasing.
As stated, that is a meaningless assertion.
Chris

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Re: What do you think about the Big Bang?

Post by Beyond » Mon Jun 21, 2010 5:03 am

Chris, could you give me a brief explanation of your definition of "inflation" and of "expansion"?
My definition of inflation would be a controlled expansion. Like a tire, for instance. You have an empty tire and start putting air into it. At some point it begins to get full and even starts to expand when you get to its correct pressure. Then you stop, because you have an inflated tire. The tire controls the expansion according to the design specifications. The tire is then considered to be fully inflated because the expansion has stopped.

To me, expansion is unstopped inflation. Like the Universe. It just keeps expanding until it hits a barrier that will contain it and then the expansion stops, because what-ever it is that is containing it, will be fully inflated. If for some reason the barrier does not hold, then the expansion--inflation cycle just keeps right on going.
Right now its late at night, but i don't see how - in the case of the universe - that you can have inflation with-out expansion. I think it was in this website somewhere that i recently was reading about how the force that drives the Universe was pushing against everything in all directions. I thought that was strange until i realized that that force has been pushing against everything for so long that it has to be growing in order to keep exerting pressure on everything, and if its growing - then it must be alive, as inanimate objects cannot grow enought to cover such a vast expanse.
Last edited by Beyond on Mon Jun 21, 2010 12:58 pm, edited 1 time in total.
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