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Branes Collision - Big Bang Imagine universe occurred when two parallel branes collided, Momentum of Branes converted to big bang kinetic energy after Collision. Thus, high-energy quanta are high-Vibrating strings.

what cosmological issues can be particularly well explained by such a brane scenario? what direct or indirect experimental evidence would support it?

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Ok, that looks like a better one. Although asking about what problems this scenario has, could lead to quite "spicy" answers and comments :-/ ... Maybe you could alternatively ask (in the last sentence) about what cosmological issues can be particularly well explained by such a brane scenario, or what direct or indirect experimental evidence would support it? –  Dilaton Nov 18 '12 at 19:58
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There exists such a model and it is described in a wikipedia article, the Ekpyrotic Universe.

The ekpyrotic model came out of work by Neil Turok and Paul Steinhardt and maintains that the universe did not start in a singularity, but came about from the collision of two branes. This collision avoids the primordial singularity and superluminal expansion while preserving nearly scale-free density fluctuations and other features of the observed universe. The ekpyrotic model is cyclic, though collisions between branes are rare on the time scale of the expansion of the universe to a nearly featureless flat expanse. Observations that may distinguish between the ekpyrotic and inflationary models include polarization of the cosmic microwave background radiation and frequency distribution of the gravitational wave spectrum.

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here especially i am asking about quantum-string duality. –  Neo Nov 18 '12 at 20:16
@Dilaton where would you take cover? ;) –  Prathyush Nov 19 '12 at 2:40
@Neo You are not asking about quantum-string duality, you are not mentioning the word, and there is no indication in your question to what this is dual to. Have a look at this talk to see what people are talking about when they talk of dualities in string theories : conservancy.umn.edu/bitstream/53194/1/Shifmania09-tseytlin.pdf –  anna v Nov 19 '12 at 5:02
@Neo I have expounded on this three times already. A quantum is a specific quantity in the value of a variable, energy, momentum, angular momentum, space,... . Take a violin string. It has specific frequencies according to the tuning. Those frequencies are quantized, i.e. they are not continuous. There are mathematical equations describing a violin string. There are mathematical equations describing the behavior of matter. The solutions of these equation sometimes give quantized results for the variables involved, similar as with the violin string. The quanta come form the boundary –  anna v Nov 19 '12 at 14:57
@Neo continued: the quanta come from the boundary conditions of the problem under consideration, i.e. the solution of the differential equations describing the problem. In string theory in ten or more dimensions, the quanta of the string can be identified with the quantum numbers of the elementary particles ( and this is the second time I give the link en.wikipedia.org/wiki/Standard_Model ) because the same groups into which the elementary particles are grouped are obeyed by the solutions of the string equations. –  anna v Nov 19 '12 at 15:01
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