Why is this so hard for you to understand, this is not a controversial subject. The physics community fully understands the limits of General Relativity at the planck scale. Maybe this will help:
At the Planck scale, there was a question as to whether standard quantum field theories would still be valid. There was never any question that General Relativity would still be valid, as it was already known that it must be if General Relativity is correct. The Wikipedia passages that you quote say nothing about General Relativity being invalid at the Planck scale, and if they had then they would be erroneous.
The Wikipedia passage that you quote concerns gravity not having been integrated with quantum field theory, i.e., Quantum Mechanics and the Standard Model of particle physics. It says nothing about General Relativity being invalid at the Planck scale, and if it had said that it would be incorrect.
We've known for some time that the infinities of gravitational collapse are unavoidable in General Relativity (i.e., given realistic energy conditions). As Charles W. Misner, Kip S. Thorne and John Archibald Wheeler wrote in Gravitation (San Francisco, Cal.: W. H. Freeman and Company, 1973), p. 934, "That singularities are very general phenomena, and cannot be wished away, has been known since 1965, thanks to the theorems on singularities proved by Penrose, Hawking, and Geroch."
Now that we have the Feynman-DeWitt-Weinberg quantum gravity/Standard Model Theory of Everything (TOE), gavity has been integrated with quantum field theory.
If I am not mistaken it is fully dependent on the Many Worlds view.
Like much of your mistaken notions on physics, you are also mistaken on this.
I support the Many Worlds interpretation, but that does not mean it is the correct interpretation. The truth is we do not know which interpretation is true. Many Worlds is a very popular view, but the Copenhagen interpretation is considered the more standard interpretation.
Copenhagen is just as popular if not more popular, though it is loosing favor it seems. Consider this:
Just to make this short, the fact that Tipler does not have a Nobel Prize for his supposed TOE is proof that it is not accepted as "THE" TOE!
It took the physics community some 40 years to finally accept the Big Bang theory due to their displeasure with its religious implications, even though it was an unavoidable result of the standard physics since the 1930s.
Yes well Krauss wrote that paper before observational evidence showed that the universe was flat.
Thats nice but that is not the case, read this:
All evidence points to a flat eternally expanding universe.
I am sure he feels differently now that we have observational evidence to show that the universe is flat.
Again, you're confused about physics. It's been known for a long time that the universe is very close to being flat.
You're also confused about the difference between a closed, flat, and open universe. The universe is currently accelerating in its explansion, which if this continued forever would make the universe open, not flat.
And your comments on the Krauss and Turner paper are mistaken. They were quite well-aware that experiments indicated that the universe was accelerating in its expansion. As they wrote in the paper:
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This speculation received dramatic support a year ago, with independent claims by two groups that Type 1a supernova, when used as standard candles, indicated that the expansion of the Universe is *accelerating* [3, 4]. The simplest explanation of this result is the presence of a cosmological constant. [Their emphasis.]
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But the point of their paper is that there is no set of cosmological observations that can be performed that can tell us what the ultimate fate of the universe will be. From their paper:
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The recognition that the cosmological constant may be non-zero forces us to re-evaluate standard notions about the connection between geometry and the fate of our Universe. An open Universe can recollapse, and a closed Universe can expand forever. As a corollary, we point out that there is no set of cosmological observations we can perform that will unambiguously allow us to determine what the ultimate destiny of the Universe will be.
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From Lawrence M. Krauss and Michael S. Turner, "Geometry and Destiny", General Relativity and Gravitation, Vol. 31, No. 10 (October 1999), pp. 1453-1459; also at arXiv:astro-ph/9904020, April 1, 1999.
http://arxiv.org/abs/astro-ph/9904020
Or perhaps a motivation is that relativity breaks down and we need more understanding of high energy physics, and some theories that include singularities say that whenever a singularity takes place a new universe is born, see Lee Smolin's Fecund Universes.
As I said, one motivation for such new laws of physics which have no experimental support whatsoever is an attempt to avoid singularities, which are unavoidable in General Relativity (per the Penrose-Hawking Singularity Theorems).