# Understanding Our Universe : Current Status and Open Issues

@article{Padmanabhan2005UnderstandingOU, title={Understanding Our Universe : Current Status and Open Issues}, author={Thanu Padmanabhan}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2005}, pages={175-204} }

1. Prologue: Universe as a physical system Attempts to understand the behaviour of our universe by applying the laws of physics lead to difficulties which have no parallel in the application of laws of physics to systems of more moderate scale — like atoms, solids or even galaxies. We have only one universe available for study, which itself is evolving in time; hence, different epochs in the past history of the universe are unique and have occurred only once. Standard rules of science, like…

## 62 Citations

Quantum Versus Classical Nature of the Early Universe and Its Consequences (Entanglement

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We look at early universe space-time which is characterized by a transition from Pre Planckian to Planckian space-time. In doing so we also invoke the geometry of Octonionic non commutative structure…

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We examine the role of particle nucleation in the initial universe, and argue
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I review the problem of dark energy focussing on cosmological constant as the candidate and discuss what it tells us regarding the nature of gravity. Section 1 briefly overviews the currently popular…

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We first of all consider what if the initial inflaton was nearly zero instead of proportional to a Planck mass, in a SUSY type potential. Using the construction of Padmanabhan about general inflaton…

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A finite vacuum energy density implies the existence of a UV scale for gravitational modes. This gives a phenomenological scale to the dynamical equations governing the cosmological expansion that…

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Higher-dimensional cosmology provides a natural setting to treat, at a classical level, the cosmological effects of vacuum energy. Here we discuss two situations: in the first case we start with an…

## References

Structure formation in the universe

- Physics
- 1993

Preface Part I. The Smooth Universe: 1. Introducing the Universe 2. The Friedmann model 3. Thermal history of the Universe Part II. The Clumpy Universe: 4. Growth of linear perturbations 5.…