Why the Universe is Just So

  title={Why the Universe is Just So},
  author={Craig Hogan},
  journal={Reviews of Modern Physics},
  • C. Hogan
  • Published 16 September 1999
  • Physics
  • Reviews of Modern Physics
Some properties of the world are fixed by physics derived from mathematical symmetries, while others are selected from an ensemble of possibilities. Several successes and failures of ‘‘anthropic’’ reasoning in this context are reviewed in light of recent developments in astrobiology, cosmology, and unification physics. Specific issues raised include our space-time location (including the reason for the present age of the universe), the time scale of biological evolution, the tuning of global… 

Figures from this paper

Theoretical and observational aspects of the variation of fundamental constants of Nature
The fundamental constants of Nature play a crucial role in our understanding of the Universe. They represent the limits of our knowledge of the laws of Physics but at the same time encode new
Varying Constants, Gravitation and Cosmology
  • J. Uzan
  • Physics
    Living reviews in relativity
  • 2011
The relations between the constants, the tests of the local position invariance and of the universality of free fall are detailed, and the unification mechanisms and the relation between the variation of different constants are described.
The degree of fine-tuning in our universe — and others
Universe or Multiverse?: Quarks, electrons and atoms in closely related universes
In a model where a multiverse wavefunction explores a multitude of vacua with different symmetries and parameters, properties of universes closely related to ours can be understood by examining the
Stars in other universes: stellar structure with different fundamental constants
Motivated by the possible existence of other universes, with possible variations in the laws of physics, this paper explores the parameter space of fundamental constants that allows for the existence
Dynamics of M theory vacua
At very early times, the Universe was not in a vacuum state. Under the assumption that the deviation from equilibrium was large, in particular, that it is higher than the scale of inflation, we
The Universal Arrow of Time is a Key for the Solution of the Basic Physical Paradoxes
The modern classical statistical physics, thermodynamics, quantum mechanics and gravity theory are developed and well-known theories. The described theories are developed and well studied for a long
Dynamics of dark energy
We review in detail a number of approaches that have been adopted to try and explain the remarkable observation of our accelerating universe. In particular we discuss the arguments for and recent
Nuclear processes in other universes: Varying the strength of the weak force
Motivated by the possibility that the laws of physics could be different in other regions of space-time, we consider nuclear processes in universes where the weak interaction is either stronger or


The Anthropic Cosmological Principle
Is there any connection between the vastness of the universes of stars and galaxies and the existence of life on a small planet out in the suburbs of the Milky Way? This book shows that there is. In
Structure formation in the universe
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.
The Fitness of the Environment, an Inquiry Into the Biological Significance of the Properties of Matter
DARWINIAN fitness is compounded of a mutual relationship between the organism and the environment. Of this, fitness of environment is quite as essential a. component as the fitness which arises in
Early life on earth
This study is organized around three themes: the origin and early diversification of life during the Archean Eon; the maturation of life and the Earth during the long Proterozoic Eon; and the
Before the beginning
Confrontation of Cosmological Theories with Observational Data
Universes (Routledge, New York)
  • Phys. Rev. D
  • 1994
Proceedings of ICTP summer school
  • Proceedings of ICTP summer school
  • 1996
Before the Beginning (Reading: Perseus) Riess
  • Critical Dialogues in Cosmology
  • 1009