What is the Big Bang Theory?

The following I found quite a simplistic explanation:

http://www.physicsoftheuniverse.com/topics_bigbang.html

Therefore, to those who claim that the very idea of a Big Bang violates the First Law of Thermodynamics (also known as the Law of Conservation of Energy) that matter and energy cannot be created or destroyed, proponents respond that the Big Bang does not address the creation of theuniverse, only its evolution, and that, as the laws of science break down anyway as we approach the creation of the universe, there is no reason to believe that the First Law of Thermodynamics would apply.

The Second Law of Thermodynamics, on the other hand, lends theoretical (albeit inconclusive) support to the idea of a finite universe originating in a Big Bang type event. If disorder and entropy in the universe as a whole is constantly increasing until it reaches thermodynamic equilibrium, as the Law suggests, then it follows that the universe cannot have existed forever, otherwise it would have reached its equilibrium end state an infinite time ago, our Sun would have exhausted its fuel reserves and died long ago, and the constant cycle of death and rebirth of stars would have ground to a halt after an eternity of dissipation of energy, losses of material to black holes, etc.

 

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How would you construct a flat plane in a curved universe? Lasers? Parallel lines in a (positively) curved universe will converge.

 

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Bingo!
And this is what cosmologists mean when we say our Universe is flat: Two lasers emitted parallel, will remain parallel.
If the Universe was closed, the two lasers over time would converge.
If the Universe was open, the two lasers would diverge.
See WMAP:

 

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What does this have to do with the value of pi in a flat plane?

Regardless of the physical laws of whichever Universe you're in, the value of pi in a plane of curvature x will be consistent with the value of pi in another Universe with the same curvature of x.

As far as we know, for our own Universe the value of x appears to be 0.

 

Point of order: clarification of terms.

Yes, the value pi is a constant, equal to 3.14159... it can't change because it is defined to be that number. But it is just a number.

It happens to be a very useful number - it is C/d on a flat plane.
But is not so on curved surfaces, or in curved universes.

What we're talking about is not a number, it is C/d of a circle.

That's not what you initially said. You said

Technically yes, the number pi will be 3.14159... in any universe (where there's a human to define it as such, since it's a defined number). But that's trivial.

The key is that, in a curved universe, C/d will not resolve to pi. eg. In a universe* that is one metre in diameter, a circle of diameter one metre will have a C/d of ... exactly 2.

*i.e. if one or more of the fundamentals of another universe were different than ours.

 

Natural selection is a human concept. That does not mean animals on the savanah didn't live and die before we came along.

More on-point: the natural world does not add one sun to another sun and get two suns.

1+1=2 is only true because we define it to be so. Specifically, we define what we mean by 'adding' two things. It is a fundamental axiom.

And it is not always true, even in our own mathematics. We don't have to invoke every axiom all the time.

 

In this universe the local proper frame is essentially flat. GR predicts the local spacetime curvature is an infinitesimal. As evidenced by the delta tick rate between the local,proper frame of the GPS satellite clock and local proper frame tick rate for a clock on the earths surface. The delta is an infinitesimal but in this case necessary to include in the analysis. This is the delta
dt_satellite - dt_earth = .0000000004453 s.
For the GPS to work you need to account for this infinitesimal local effect of gravity. For most every other experiment conducted in the local proper frame the effect is an infinitesimal which has no bearing on the experimental results. Essentially the local proper frame throughout or universe is the same as the boundary Schwarzschild coordinate. At rest flat spacetime far away from the strong field. The geodetic effect predicted by GR was measured during the Gravity Probe B experiment. The geodetic effect is the local spacetime curvature. Gravity.

 

Eternal Inflation predicts that space and time exists before the inflation event responsible for our expanding universe. This is quite a prediction relative to what you've believed your entire life. This is interesting enough for cosmologists to empirically observe the CMBR for a predicted 'signature' possibly revealing a collision with a different universe. First the WMAP data was analyzed now the Planck data at a greater experiment resolution. Trippy stuff.
http://arxiv.org/abs/1510.00126

 

bruce...Obviously you are a proponent of this eternal inflation: Which correct me if I'm wrong, means that inflation is happening all the time and different regions beyond our observable universe, are still experiencing Inflation.
Also a while back, I came across a term called "Chaotic Inflation" which seemed from memory somewhat similar to eternal inflation. Any comments?
My knowledge of Inflation is pretty basic so go easy with me. Of late though, I'm finding certain aspects of it that are attractive along with string/membrane theory could be a QGT if we had the technology to research and probe at those levels.
[Which means imho that it still should be getting research funds]
Any obvious errors, alterations and/or corrections in my thoughts on this?

 

Whats the problem?

Shape of universe (Curved / Flat) will pose no problem in having a flat surface unless you are at the boundary (?). The problem will come only if your local spacetime is curved due to extreme gravity, in that case any flat panel object will be deformed.

 

This guy, Alan Guth, can explain the difference between chaotic inflation, discovered by Andre Linde, and new inflation. It has to do with how the potential seeks a minimum. They're different figures showing how the potential changes. A discussion about both potentials and the figures are ~ between page 5 and page 8. This paper was written in 2007 and intended to summarize the path of Inflation to that point. I know you're working on a fun holiday. Have a great one.
http://arxiv.org/abs/hep-th/0702178

 

I lay awake last night rolling this over in my head. I get it now.

In any universe with any size or curvature, you can still derive pi easily enough.

As the size of your circles grow smaller, their C/d will converge on pi. This is what is meant by 'Locally, C/d will always equal pi'.

Pi is a universal constant.

It is our universe, being nearly flat, that is a special case; it's the only shape where C/d=pi regardless of how large a circle you measure.

OK, point conceded.

 

Thanks bruce and you and your's have a good one too.

 

Exotic Word Salad..

 

Only to an illiterate fool.
http://arxiv.org/abs/1404.2601
Inflation and String Theory
Daniel Baumann, Liam McAllister
(Submitted on 9 Apr 2014)
We review cosmological inflation and its realization in quantum field theory and in string theory. This material is a portion of a book, also entitled "Inflation and String Theory", to be published by Cambridge University Press.

http://www.cambridge.org/us/academi...physics/inflation-and-string-theory?format=HB
LOOK INSIDE

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Inflation and String Theory
""""""""""""""""""""""""""""""""""""""""""

http://www.sciforums.com/threads/what-is-the-big-bang-theory.153903/page-4#post-3347715
It has to be there in a theory of strings. So, the first great achievement of String Theory was to give a consistent theory of quantum gravity, which resembles GR


http://arxiv.org/abs/1105.6359
Is string theory a theory of quantum gravity?
Steven B. Giddings
(Submitted on 31 May 2011 (v1), last revised 21 Nov 2011 (this version, v2))
Some problems in finding a complete quantum theory incorporating gravity are discussed. One is that of giving a consistent unitary description of high-energy scattering. Another is that of giving a consistent quantum description of cosmology, with appropriate observables. While string theory addresses some problems of quantum gravity, its ability to resolve these remains unclear. Answers may require new mechanisms and constructs, whether within string theory, or in another framework.

 

Sorry, what is exotic-y or word salad-y about string theory, membrane theory or quantum gravity?
Or are simply calling out the non sequitur of name-dropping some technical terms?

 

Can you decipher the below ?

......[inflation]....Of late though, I'm finding certain aspects of it that are attractive along with string/membrane theory could be a QGT if we had the technology to research and probe at those levels.....

 

In your original post which contained the 'word salad' you admitted not knowing much about all these. So let me guide you with basics..

Your first reference first line is

...........We review cosmological inflation and its realization in quantum field theory and in string theory.....


To start with you must understand that cosmic inflation is a process, while string theory is about fundamental nature of matter. So these references attempt to explain the inflation process (relaization in QFT and ST).

Now you will be able to appreciate the reference given by you in a proper perspective, you will yourself be amused by what you have written.

 

I doubt your ability to guide anyone while burdened as you are with your magic pixie and delusions of grandeur.
The little I do know with regards to Inflation, eternal or otherwise, still ranks above your pseudoscience application.

My only amusement is that associated with your continued bullshit.

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The facts remain that GR and BB theory stands as the unchallenged accepted theory of the evolution of the universe/spacetime and the subsequent geometry of GR in the presence of mass.

Worth noting in your time on this forum so far, as your present handle and under rajesh, the lack of achievements that you have clocked up.......the paper you have had demolished, the other paper you had rejected, the threads you have had moved to alternative sections and even pseudoscience, the general anti mainstream stance you have taken that has in every instant been rejected by all on this forum, and also by the many professionals that our friend tashja has obtained for us.
I say you have won the wooden spoon for the forums most ignored and derided nonsense, although a close race when we add the likes of jcc and constant theorist. Congrats.

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Subsequent geometry of GR ? (Ok, slip of keyboard ?)

You are right as far as GR is concerned it is as on date unchallenged, but there are issues with it. Due to these issues alternatives are being proposed and thought of but none could reach to the level of acceptance as that of GR. But the question is not about GR not getting challenged comprehensively, the question is when ? Its a matter of time only. You have no argument on the content, your sole no-argument is that GR is unchallenged so it must be true.