Brane Gases in the Early Universe

D. Easson (Brown Univ.); R. Brandenberger; S. Alexander

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Brane Gases in the Early Universe

S. Alexander, R. Brandenberger, D. Easson (Brown Univ.)

High Energy Physics - Theory · Submitted 23 May 2000

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim In particular, we argue that the string winding modes will only allow four space-time dimensions to become large.

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What the abstract itself states, as probabilities: claims first 0.04 · states limitation 0.27 · human participants 0.01 · controlled comparison 0.02 · randomized assignment 0.01 · states quantitative result 0.58 · compares with prior results 0.10 · mentions code or data availability 0.01.

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arXiv listing abstract v2. Results and the main claim are underlined; show every role.

Over the past decade it has become clear that fundamental strings are not the only fundamental degrees of freedom in string theory. D-branes are also part of the spectrum of fundamental states. In this paper we explore some possible effects of D-branes on early Universe string cosmology, starting with two key assumptions: firstly that the initial state of the Universe corresponded to a dense, hot gas in which all degrees of freedom were in thermal equilibrium, and secondly that the topology of the background space admits one-cycles. We argue by t-duality that in this context the cosmological singularities are not present. We derive the equation of state of the brane gases and apply the results to suggest that, in an expanding background, the winding modes of fundamental strings will play the most important role at late times. In particular, we argue that the string winding modes will only allow four space-time dimensions to become large. The presence of brane winding modes with $p > 1$ may lead to a hierarchy in the sizes of the extra dimensions.

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What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	Over the past decade it has become clear that fundamental strings are not the only fundamental degrees of freedom in string theory.	background 1.00	0.05	0.02	asserted 1.00
s1	D-branes are also part of the spectrum of fundamental states.	background 1.00	0.05	0.02	asserted 1.00
s2	In this paper we explore some possible effects of D-branes on early Universe string cosmology, starting with two key assumptions: firstly that the initial state of the Universe corresponded to a dense, hot gas in which all degrees of freedom were in thermal equilibrium, and secondly that the topology of the background space admits one-cycles.	contribution 0.61	0.64	0.04	hedged possibility 0.49
s3	We argue by t-duality that in this context the cosmological singularities are not present.	result 0.92	0.83	0.20	asserted 0.99
s4	We derive the equation of state of the brane gases and apply the results to suggest that, in an expanding background, the winding modes of fundamental strings will play the most important role at late times.	result 0.53	0.95	0.24	hedged possibility 0.96
s5	In particular, we argue that the string winding modes will only allow four space-time dimensions to become large.	result 0.62	0.84	0.46	asserted 0.64
s6	The presence of brane winding modes with $p > 1$ may lead to a hierarchy in the sizes of the extra dimensions.	interpretation 0.71	0.62	0.09	hedged possibility 1.00

What kind of paper the classifier reports this is: theoretical result 1.00 · evidence from proof or derivation 0.64.

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The paper

Original abstract

Over the past decade it has become clear that fundamental strings are not the only fundamental degrees of freedom in string theory. D-branes are also part of the spectrum of fundamental states. In this paper we explore some possible effects of D-branes on early Universe string cosmology, starting with two key assumptions: firstly that the initial state of the Universe corresponded to a dense, hot gas in which all degrees of freedom were in thermal equilibrium, and secondly that the topology of the background space admits one-cycles. We argue by t-duality that in this context the cosmological singularities are not present. We derive the equation of state of the brane gases and apply the results to suggest that, in an expanding background, the winding modes of fundamental strings will play the most important role at late times. In particular, we argue that the string winding modes will only allow four space-time dimensions to become large. The presence of brane winding modes with $p > 1$ may lead to a hierarchy in the sizes of the extra dimensions.

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References

Forward citations

Cited by 11 Pith papers

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How the literature uses it

31 arXiv papers cite this in 40 sentences

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Papers citing it · 26 sentences without a confident label

Builds on it 2 papers

In a paper by Alexander, Brandenberger and Easson [ref] the setup of [ref] was extended to include p-branes for $p=0,1,2,4,5,6,8$ in the weak-coupling limit of M-theory with one small dimension compactified on $S^1$ (type IIA string theory).

Dynamical Decompactification and Three Large Dimensions · Introduction · 0.99
While the original string gas cosmology exclusively discusses closed string degrees of freedom, there is a natural extension involving branes [ref] ; since a dilute gas of D-branes converts closed strings to open strings efficiently, it is reasonable to expect that the energy density in a brane-supported SM would dominate over closed string dark radiation in a variation of the mechanism described here.

Dark Radiation and the Hagedorn Phase · Conclusion and Discussions · 0.83

Compares with it 2 papers

The underlying dynamics is distinct from those in [ref] and can be described as follows.

Stabilisation of Seven Directions in an Early Universe M -- theory Model · Introduction · 0.89
(Note that the `fractional brane gas' is completely different from the traditional `brane gas' [ref] where we have essentially free (i.e. non-intersecting) branes with $S∼E$.)

The information paradox: conflicts and resolutions · Implications for Cosmology: a conjecture · 0.85

Cites it as background 8 papers

The brane gas models [ref] are extension of the idea and have been considered a cosmological role of windings of D-branes.

Wrapped brane gas as a candidate for Dark Matter · Introduction · 0.86
It provides a mechanism which inflation [ref] and many alternatives [ref] rely on to generate cosmological inhomogeneities seeding the Cosmic Microwave Background (CMB) [ref] and the Large Scale Structure (LSS) [ref] of the universe.

Decoherence out of fire: Purity loss in expanding and contracting universes · Introduction · 0.83
Scale invariance was attempted in the context of bouncing models with a contracting phase such as Ekpyrotic [ref] , String Gas [ref] and Pre-Big-Bang scenarios [ref] .

Fermi-bounce Cosmology and scale invariant power-spectrum · Introduction · 0.98

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