Preface

The current standard model of cosmology, also called the concordance cosmological model or the Lambda-C M model, assumes that the universe was created in the "Big Bang" from pure energy and is now composed of about 5% ordinary matter, 27% dark matter, and 68% dark energy. This cosmological model is based primarily on two theoretical models: (1) the standard model of particle physics, which describes the physics of the very small in terms of quantum mechanics, and (2) the general theory of relativity, which describes the physics of the very large in terms of classical physics. Both these theoretical models are considered to be incomplete in the sense that they do not provide any understanding of several empirical observations, such as the Big Bang, dark matter, dark energy, gravity, and matter-antimatter asymmetry in the universe. In addition, the current standard model of cosmology makes several assumptions involving the homogeneous and isotropic nature of the universe and two unknown entities called dark matter and dark energy. The main aim of this book is to discuss these serious problems that threaten to undermine the current standard model of cosmology.

In the introductory Chapter 1, numerous dubious assumptions of the current standard model are discussed in some detail. The following Chapters 2–6 are divided into two main sections. Section 2 is devoted primarily to alternatives to the Big Bang scenario of the standard model based on modifications of the steady-state models that were popular prior to the discovery of cosmic microwave background radiation. Section 3 contains chapters that discuss modifications to the general theory of relativity. These include suggestions of alternative models that provide a generalization of the field equations of the general theory of relativity and a generalization of the equivalence principle to reconcile quantum mechanics and general relativity.

> **Brian Albert Robson** Honorary Professor, Research School of Physics and Engineering, The Australian National University, Canberra, Australia

Section 1

Introduction

1

Section 1 Introduction

Chapter 1

Brian Albert Robson

1. Introduction

entities.

3

Introductory Chapter: Standard

The current Standard Model of Cosmology (SMC), also called the "Concordance Cosmological Model" or the "ΛCDM Model," assumes that the universe was created in the "Big Bang" from pure energy, and is now composed of about 5% ordinary

While the SMC is based primarily upon two theoretical models: (1) the Standard

The main additional assumptions of the SMC are: (1) the universe was created in

Unfortunately, both the SMPP and the GTR are considered to be incomplete in

The main aim of this Cosmology Book is to discuss the above serious problems

The current SMC has numerous dubious assumptions that will be discussed in the following. It will be indicated that many of the problems associated with the SMC arise from the dubious assumption that the GTR is valid for all distances

Model of Particle Physics (SMPP) [2], which describes the physics of the very small in terms of quantum mechanics and (2) the General Theory of Relativity (GTR) [3], which describes the physics of the very large in terms of classical

the Big Bang from pure energy; (2) the mass energy content of the universe is given by 5% ordinary matter, 27% dark matter, and 68% dark energy; (3) the gravitational interactions between the above three components of the mass energy

content of the universe are described by the GTR; and (4) the universe is

the sense that they do not provide any understanding of several empirical observations. The SMPP does not provide any understanding of the existence of three families or generations of leptons and quarks, the mass hierarchy of these elementary particles, the nature of gravity, the nature of dark matter, etc. [4]. The GTR does not provide any understanding of the Big Bang cosmology, inflation, the matter-antimatter asymmetry in the universe, the nature of dark energy, etc. Furthermore, the latest version of the SMC, the ΛCDM Model is essentially a parameterization of the Big Bang cosmological model in which the GTR contains a cosmological constant, Λ, which is associated with dark energy, and the universe contains sufficiently massive dark matter particles, i.e., "cold dark matter." However, both dark energy and dark matter are simply names describing unknown

mechanics; it also depends upon several additional assumptions.

homogeneous and isotropic on sufficiently large (cosmic) scales.

that threaten to undermine the foundations of the current SMC.

2. Dubious assumptions of SMC

Model of Cosmology

matter, 27% dark matter, and 68% dark energy [1].

#### Chapter 1
