Extensive Big Bang speculation

[col]

Its a bit like trying to explain the Big Bang to OTers.

 

[El_Machinae]

Thus my point to those who don't believe it. It's more of a metaphore (sp). (same with 'waters' - how do you explain the vacuum of space to ancient people?)

The name chosen (the Big Bang) is a poor one, because I have to endlessly explain that it wasn't an explosion in space. And it takes a long time to convince people that their mental image is not what we're explaining.

 

[batteryacid]

As the universe started as singularity of TIME and in SPACE, there is no "before" and the universe didn´t sit there for thousands of years before it exploded, because THERE WAS NO TIME - it´s hard to grasp this as we are creatures of 3 space and one time dimension.

Also a reason for the big bang is not neccessary, as all singularites face quantum effects, with random probabilites for event to occur or not occur, without particular reason (such as the manifestation of particle-anti particle pairs from nothing)

Also, it doesn`t expand INTO something, simply the distances grow larger- I think in one of Hawking´s books there was the analogy of people living on a flatland on a air balloon that grows larger- distances grow larger on the surface of the balloon without the need of "empty surface" around it.

The bran theories are very interesting, but I think that most of the analogies in pop. scientific journals do not express the mathematical implications of the bran models nearly ( I even think that most scientist which work with these mathematical constructs face a real problem in interpretation, as it is already hard enough to go into a fourth space dimension- most models work with 18 or so I think) - but they are good stuff for sci fi writers I think

 

[the mormegil]

I don't a huge ammount about this but I'll explain what I can.

First of all, the theory would suggest that NOTHING exists outside of this sphere. If that holds, then what is the universe expanding INTO? Surely one could speculate vacuum, orempty space, but even that would be something. Space has three dimensions in which an object may freely move.

You misunderstand, the big bang theory isn't the expansion of matter into an existing space as it were, it is the creation of spacetime itself.

A "nothing" object could perhaps occupy a zero-dimensional point. But how can a point exist if it has width, height, and length of zero?

Because it didn't 'exist'. As I said above the big bang was the creation of spacetime.

In actuality it is not there, but a definable location in a higher-dimensional region of space. We draw points to make them visible, but they are not physically there. So that cannot exist.

I didn't really understand what you meant here.

If the universe started as a singularity, which has zero dimensions, how could it have existed in the first place?

Same as above..it didn't 'exist', the big bang created the dimensions.

According to the theory, atoms were created after the big bang had already taken place, so they could not have caused a reaction internally. So what could have caused the big bang? I beleive that some external reaction would have been necessary to begin the reaction. Consider that the theory has been mapped out to the second just after the big bang occurred, so we "know" how old the universe is.

Not sure about this, quantom theory allows for seemingly random events to occur, such as things appearing from nowhere, maybe soemthing to do with this? Though I don't know whether quantum theory applies to non-dimensional things...

But what happened before that? And how long was this singularity sitting around before something made it explode? Even though time could not be calculated, can time inselt really have a definitive starting point?

Again, time didn't exist before the big bang so this question is unanswerable.

The same applies to the expanding matter, and the notion that there is nothing outside the sphere. If nothign existed out of the sphere then how could the sphere be expanding? It must be filling some 3-dimensional void, but then the void would not be pure nothingness.

I find the concept of a finite universe much more difficult to comprehend than an infinite one.

It isn't filling a dimensional void, it is creating the dimensions.

I think most of your questions come from not understanding that the big bang was the creation and expansion of spacetime (the 4 dimensions - the regular 3, with time as the 4th), not just matter expanding within dimensions.

 

[Atlas14]

How can time not exist without something else existing? The idea of time and matter magically coming into existance is bogus to me. Matter does not just "come into existance" without having already existed. It is equivalent to saying God created the Big Bang, which of course may be possible, but is untestable and cannot really be proven.

 

[warpus]

How else could it have happened?

random quantum fluctuations

The idea of time and matter magically coming into existance is bogus to me. Matter does not just "come into existance" without having already existed.

Yes it does, a la quantum physics.

 

[Atlas14]

Yes it does, a la quantum physics.

Perhaps you could expand on this quantum physics part to what Im saying. I still don't grasp it. What happened to matter cannot be created nor destroyed?

 

[Shaihulud]

I don't pretend to understand the theories on how the Universe was created, but i do like read people discussing it. Virtual particles in under quantum field theory pop out at every point in space-time. Under certain condition, the theory allows the virtual particle to become a "real" particle, of course i cannot imagine the conditions when this happens, but it should happens at the point when the Universe "bangs"

 

[Souron]

Perhaps you could expand on this quantum physics part to what Im saying. I still don't grasp it. What happened to matter cannot be created nor destroyed?

It goes out the window. With QM, matter and energy can be suddenly created, but the durration existance of such matter and energy is inversly proportional to the amount of energy created. Remmember E=mc^2, so mass comes into play if we think of it as energy.

The formula for how long such particles can exist is ΔEΔt=ħ/2.

 

[Rik Meleet]

It goes out the window. With QM, matter and energy can be suddenly created, but the durration existance of such matter and energy is inversly proportional to the amount of energy created. Remmember E=mc^2, so mass comes into play if we think of it as energy.

The formula for how long such particles can exist is ΔEΔT=ħ/2.

ħ = Planck's constant ?

 

[Atlas14]

I don't pretend to understand the theories on how the Universe was created, but i do like read people discussing it. Virtual particles in under quantum field theory pop out at every point in space-time. Under certain condition, the theory allows the virtual particle to become a "real" particle, of course i cannot imagine the conditions when this happens, but it should happens at the point when the Universe "bangs"

Wow, that actually kinda makes sense to me. Thanks

It goes out the window. With QM, matter and energy can be suddenly created, but the durration existance of such matter and energy is inversly proportional to the amount of energy created. Remmember E=mc^2, so mass comes into play if we think of it as energy.

The formula for how long such particles can exist is ΔEΔT=ħ/2.

The delta T in the last formula refers to time right?

 

[Souron]

ħ = Planck's constant ?

Reduced Planck constant, yes. AKA Dirac's constant.

E is energy. t is time. I misprinted the T; it's supposed to be lowercase.

 

[Cannae]

I think somethign had to have caused it because otherwise, the singularity wouldn't initiate the reaction. If it was just sitting in empty space not doing anything then it could sit there forever and never react, if it cannot react with itself.

I often have trouble putting my thoughts into words. Here's probably a very elementary example of what I'm trying to say. Consider a pencil. The pencil cannot write by itself; some external force (you or I) needs to make it write. Otherwise the pencil could sit around for years and nothing happens.

Mabey god caused it

 

[El_Machinae]

Perhaps you could expand on this quantum physics part to what Im saying. I still don't grasp it. What happened to matter cannot be created nor destroyed?

It can be, but on average, it acts like it doesn't.

 

[jalapeno_dude]

ħ = Planck's constant ?

I believe it's Plank's constant/(2pi).

 

[IronMan2055]

but also I thought matter could not be created nor destroyed

you could generate a nuclear explosion

 

[Birdjaguar]

How can time not exist without something else existing?

Time is just how we denote change. Until there was change, there was no "time". "Matter" with its endlessly spinning electrons and charged particles etc., introduced change into existence, and with it, time.

 

[col]

What happened to matter cannot be created nor destroyed?

We have replaced the law of conservation of mass by the law of conservation of mass-energy.

Mass can be created from energy. It happens all the time in beta decay where an electron and an antineutrino are created. You can only create particle / anitparticle pairsthough - other conservation laws concerning leptopn and baryone numbers.

Particle accelerators are also used to create matter. Hit two particles together with enough energy and you can create all kinds of new particles.

You can also go the other way and turn mass into energy. That's the basis of the energy release in nuclear reactions. One of the fun things to introduce to students is the idea that the mass of an object depends on its environment - for example sometimes a proton is heavier than a neutron; sometimes a neutron is heavier than a proton!

 

[El_Machinae]

Crap, he only said "matter". Shoot. Yeah, matter can be converted into energy and vis versa.

But, on the whole, the universe acts like new matter or energy can not be created. And this is true on average, but we see localised and temporary violation of this rule.