Question about the initial conditions of the universe

[Johnny5]

The question is pretty much self explanatory.

 

Total energy=?

Total mass=?

Temperature=?

Volume=?

Density = ?

 

Also, while I'm on the subject, what is the escape velocity of the universe, way back in time when all the matter was concentrated near the center of the universe?

 

Thank you

[5614]

Before or immediately after the big bang?

[Johnny5]

Before or immediately after the big bang?

 

 

Good question.

 

Well do you know how much time there was from the first moment in time up to the big bang, say in units of seconds?

 

And really, I guess i am interested in interpretations of the Planck units.

 

Regards

[5614]

If before the big bang nothingexisted nothing could travel along the 4th dimension meaning nothing could travel time making time effectively non-existant.

 

If a single point of 'super-energy' or 'pure-energy' or whatever it is called existed I suppose it is possible for that to travel in time, but did it? Can a 4th dimension exist without a universe? Without space-time?

 

I do not know the answers to these questions or yours, although it is very interesting, all we can do is guess.

[Johnny5]

If before the big bang nothingexisted nothing could travel along the 4th dimension meaning nothing could travel time making time effectively non-existant.

 

If a single point of 'super-energy' or 'pure-energy' or whatever it is called existed I suppose it is possible for that to travel in time' date=' but did it? Can a 4th dimension exist without a universe? Without space-time?

 

I do not know the answers to these questions or yours, although it is very interesting, all we can do is guess.[/quote']

 

I didn't say that before the big bang nothing existed.

 

The way I conceive of the first few moments in time is kind of like this.

 

There was a superforce, probably gravity, which shaped the matter, as it still does today, into the form of a sphere. Then, I see the force of gravity compressing the sphere, like a spring. And then the spring pushes back outwards, and boom. The moment of the boom, is the moment of the bang. My boom, is their bang.

 

So during the first few moments of time, gravity shaped the supermass. Not "super-energy" as you are calling it.

 

And I think it's a reasonable inference that the Planck units represent the initial conditions of the universe somehow, although honestly I'm not sure how yet.

 

And most specifically, I know there is a Planck temperature, and I am sort of interested in when the universe had that temperature. Surely not at the very first moment in time, since nothing was moving too fast at the second moment in time, hence the temperature at the first moment in time might as well be stipulated to be zero, and not the Planck temperature.

 

But as you say there is some guesswork going on, but I like to think of it more as detective work, rather than guesswork

 

Regards

 

PS: If the supermass was spinning, then things are really complicated.

[5614]

I didn't say that before the big bang nothing existed.

Yeah I know, I suggested it.

 

more as detective work, rather than guesswork

Detecive work implies there is evidence, whilst the current universe supplies evidence as to the effect of it [big bang], the universe does not supply direct evidence as to what happened, merely the effects, from which we can guess the original event (big bang)

 

I'd say there are very few people in the world who have a good idea as to the conditions before and a few seconds into the big bang (if any people do at all) and even their views (if they exist) will be contradicted by some (because it's not based on totaly solid proof), I'd say its impossibly to find a certain answer and I certainly can't tell you an answer to this, but I will watch this thread.

 

Also your way of imagining the big bang, I assume that is a personal method of visualising it, if that is the case and you are examining it in such detail, maybe questioning the method of visualisation may help, because after all that is not certain in itself.

[Johnny5]

Yeah I know' date=' I suggested it.

 

 

Detecive work implies there is evidence, whilst the current universe supplies evidence as to the [u']effect[/u] of it [big bang], the universe does not supply direct evidence as to what happened, merely the effects, from which we can guess the original event (big bang)

 

 

In "reaching" to disagree with you, I noticed something. I do agree that the current universe supplies evidence as to the, and I use this word cautiously, 'effect' of the big bang, but I do disagree that we aren't provided evidence as to what happened in the past (cause), and here's why:

 

Understanding the laws of physics really is understanding motion. And we have seen enough of 'motion' in our lives to have an almost intuitive understanding of how the universe changes as time moves fowards. In some people that intuition is large enough for them to at least imagine time running in reverse.

 

So I think the fact that we experience enough of time in one direction, allows us to understand the laws of physics, and by understanding those laws, we can reasonably be expected to "mentally run time in reverse."

 

So the evidence we have (which is foward in time evolution of the universe) actually does give insight into how the past must have been.

 

We are not totally without means to properly infer the initial conditions. I guess that's all I am trying to say. To act as though it is impossible for us to ever understand the initial conditions of the universe is not only misleading, it is wrong, for the reason I am trying to state.

 

I will give you a really simple example of what I am trying to say.

 

You know that when you drop a feather, it must fall to the earth. You have a reasonable sense of how long this takes, depending upon the initial height you drop it from. And you probably also know, that if you drop a book at the same height that you drop the feather from, that the book falls much faster, given that you released them simultaneously.

 

But now, you have learned that if you place the feather on top of the book, that the book acts like a shield, and shields the feather from the effects of air resistance, and the two now fall collectively (together) with the same acceleration, namely g.

 

So all this knowledge comes to you from experiment, and sensory perception. The experiment is repeatable, and the truth value of your knowledge isn't changing in time. So you can say you know something, and then explain it to someone who doesn't.

 

Then, using your knowledge, which has increased, you can construct a hexagon on paper, much like euclid taught how to, and then cut it a certain way, and construct a propeller.

 

In fact, you can figure out how to make a device that actually rises in the air, from the simple knowledge i am discussing now.

 

But the point to notice is that, if you saw an apple hit the ground very slowly, you could confidently conclude that (in the past, at the moment it was dropped) it wasn't dropped too high above the earth.

 

Conversely, if you saw that same apple smash into the earth and explode at 120 mph, you could conclude that it was dropped much higher (in the past).

 

So from looking at just a few moments in time, and knowing a bit about the laws of physics, you can understand what things were like earlier.

 

The present doesnt give much evidence about the past, but it does give evidence. So I disagree slightly with you.

 

And I think it would be the crowning glory of modern physics, to clearly show that we have discovered the initial conditions of the universe, through experiments that were not principally designed to find that information.

 

Whew, ok I'm done.

 

Regards

[Bettina]

Whew' date=' ok I'm done.

[/quote']

I hope your not done. Your reply made me draw pictures in my mind much like my science teacher does. It was a great reply.

 

I think 5614, by stating "direct evidence" was saying the same thing in a much shorter version.

 

Thanks very much

Bettina

 

One more thing. Why did there have to be anything before the big bang. Why couldn't there have been just nothing and we just appeared much like a quark.