Dark Knight Bob

When people use string theory to back up their arguements i'm very wary. Mainly because string theory in itself is more conceptually complex than quantum theory (even though the two are related).

I'm somewhat familiar with mathematical constructs of 12 dimensional topological systems that string theory is based around as far as i'm aware.

But whilst people say "if you say you understand quantum physics, you don't" I find people who study string theory saying "if you say you understand string theory then you need to be sedated before you make the quadratic formula explode".

String theory is one of those things that really is qualatively less sound than the big bang theory. not due to it's explanation but by how exactly it operates. I've yet to meet anyone outside of a hardcore physics field who can actually define string theory to me in a clear concise way.

So you'll have to forgive me on this occasion because string theory used in place like this isn't going to convince me of much other than when it's used in a vague sense of a trivial point of interest.

I need someone to sit down with a pencil and paper and show me the mathematical derivations of it for me to take it as a seriously talking point.

If you want to use any other arguements i'd be happy to hear them but otherwise i'll have to call a stalemate to the discussion with regards to that.

Ion

The analogy of the stretched band, is one of an open system, and outside force entering the band.

So you need to have new stuff to appear to push things apart.
The expanding universe is an open system considering:

.) addition of distance;

.) I have seen a calculation of the mass of the universe increasing.

The Second Law of Thermodynamics applies correctly to closed systems, not to open systems like the universe.

The opening post incorrectly applies the Second Law of Thermodynamics to the universe.

bogie_blogger

:notworthy That is what you were saying and I was refering to that aspect of the theory, not meaning to say you were standing behind it.

It would be interesting to know from someone who is very familiar with BBT, what position they take on the ISU. It pertains to the question of the OP on this thread about theists searching for a beginning to which they can then say "God did it".

I believe or at least understand that BBT says that the universe is expanding, and if we imagine the start of that expansion, we come to the beginning of the known universe. I do not understand BBT to say that the extremely dense and hot starting point appeared from nothing; I understand BBT to say that it was a singularity about which we have no further knowledge and before which there is no way to know. Is that understanding correct?

Dark Knight Bob

within the definition of the theory that's correct yes.

if the theory is correct and we understand enough about the nature of what singularities are then if we can trace the universe back to time=0 then you should get the answer to what caused the big bang.

There are many standard athiest arguements that deal with the whole theistic arguement of "god did it". I'm sure they're easy enough to find and don't really need to be brought up again.

The open universe theory breaks the 1st law of thermodynamics. In that you can "get something for nothing".

All energy that has been detected to have been "created" has merely been short-term "rental" of energy. It still follows the laws of thermodynamics and is mathematically evened out again.

An open universe would have matter/energy coming into the universe everywhere or at least in areas of expansion.

You actually get the contrary. With quantum physics you get particles and such actively resisting such effects. Where the energy reaches it's irreducable component nothing more is created. You will get effects that fall in line with a closed universe.

There are a lot of bizarre effects that do happen at high energy physics but these still fall into line with the laws of thermodynamics.

The only point in which the laws seem slightly "weird" is right at the begining where the question asked is "well what kick started everything" and that is what physics is trying to solve (multiverse? infintiely expanding contracting universe? different laws of universe existing?), but to talk about the begining of the universe when you are talking about when all the universal forces were the same thing (gravity, electromagnetism, strong/weak force) and to track back to now and say "thus the laws of thermodynamics can no longer apply" is a bold statement that requires an extrordinary amount of evidence.

bogie_blogger

:thumbs: That is exactly right, and let's rest comfortably believing that no such evidence will be brought forth.

Tracking back to the point when all forces must have been unified and the known universe was at the earliest "known" time, and before that ... we can't know. But the instant before that, when all the forces were unified at the point of greatest density and heat, something might have happened based on natural laws of physics. That something might have been the event of critical mass/heat/density, a constant. An event that requires X amount of matter/density in order to unify all forces in order to cause the reaction we observe as the expanding universe. The matter/energy/heat/density ratio would be finite. The same ratio would produce the same results that effectively cordon off the known universe from anything before or beyond it; a barrier that will never be penetrated. The ISU.

Ion

The open universe doesn't necessarily break the First Law of Thermodynamics.

The universe's mass is increasing, so there must be newly created matter in the universe.

The open universe and the string theory allow for the newly expanded distance to be populated by particles created as 'children' of existing particles, not out of nothing, but out of 'parent' particles.

Same as the globe's population is increasing, the universe's particles are increasing.

But this is still only a theoretical explanation for the expansion of the universe, so far...

Schneibster

The First Law of Thermodynamics is the law of the conservation of energy. If the universe is "open," then energy is being added to it. This is a violation of the law of the conservation of energy. Q.E.D.

The First Law of Thermodynamics is conservation of energy; according to relativity, mass and energy are interchangeable. Therefore "newly created matter" breaks the First Law of Thermodynamics. Q.E.D.

Furthermore, you are assuming that the mass of the universe is increasing. Prove it.

This could only be consistent with energy conservation if the existing particles became smaller. The mass of the proton is the minimal baryon mass; protons do not decay as far as we can tell (and we have pushed the shortest possible half-life beyond 10^33 years in the Soudan 2 experiment). Protons are by mass the most common matter in the universe; by mass, they make up about 85% of all the visible mass in the universe (74% is hydrogen, and 22% helium; hydrogen is a proton, and half of helium is protons- do the math). If anything is getting created at any significant rate out of anything, as you suggest above, it must be protons, and they must be turning into something lighter.
1. Their half-life precludes it.
2. There is nothing lighter for them to turn into without violating various other conservation laws (color charge conservation, primarily).
Q.E.D.

This is a completely groundless simile. The reasons for the population increase have nothing to do with nuclear physics, nor with possible violations of energy conservation.

You might as well say, "My beer is flat. My wallet is flat. That waitress is flat. Therefore, the world must be flat!"

So far, this is complete and utter nonsense. Not merely contradicting the known laws of physics, but either self-contradictory or faulty reasoning. You'll need to do far better than this for anyone to take you seriously.

Ion

The First Law of Thermodynamics applies to closed systems.
An open system doesn't violate the law, the law doesn't apply.

Ditto for the the Second Law of Thermodynamics: it doesn't apply to open systems.
(I am stating elementary knowledge of closed systems in thermodynamics, here)

The mass of the universe is increasing, new matter is in, therefore the universe is an open system.

Dark Knight Bob

You still haven't supplied any evidence that this is actually happening though.

Give me one example of spontaneous, permanent creation of energy/matter.

If this energy is being created where is it coming from? If it's coming from somewhere this still implies a closed system with our universe and wherever the energy is coming from.

If this energy is coming out of nowhere then the universe doesn't obey thermodynamics and everything from gravity to electromagnetism wouldn't work. It wouldn't have any natural tendancy towards it.

As i said already you cannot have a true vacuum (which has been proven) which would be required for an open universe because being able to do so would imply that you could have a non-interlinked flow of energy i.e an open system.

Everything experimentally shown works because of thermodynamics. If you take the universe to be non-isotropic (which it isn't) and non-homogeneous then nothing works anymore. The universe has to be a closed system to work.

Ion

I have seen articles about a closed universe, where the mass doesn't increase but just the distance between galaxies does, toped by articles about an open universe, or flat universe, where the mass does increase.

(Note: by mass increase I am not referring to Einstein's increase of mass at increasing speed near the speed of light, which is a perception of mass under different conditions, I am referring here to dark matter's mass)

For example, this:

http://physicsweb.org/articles/news/2/11/3/1

has "...This implies that the universe is 'open' and will expand forever. It also suggests that a bizarre quantum force is affecting the expansion. Astronomers have been puzzling over the expansion rate of the Universe and its mass..."

while "...If the mass of the Universe is large enough, the expansion will eventually decrease and the Universe will then collapse in on itself. However if the density of the matter in the Universe is less than a certain critical density, it will continue to expand for ever...It suggested that the expansion rate was actually increasing rather than decreasing..." equates expansion of the universe with increase of density, therefore of mass.

As for spontaneous creation of matter, physicists look into quantifying the dark matter and its mass.