The Intelligible Universe

The following sections are included:

• Contents

• Prologue to 2nd Enlarged Edition

• Acknowledgements and Credits

The following sections are included:

• Einstein's Eternal Mystery

• From Antiquity to the XVI Century

• From Galileo and Newton to Kirchhoff

• The XX Century

• Bibliography

The following sections are included:

• The Last Word in Physics

• Precise Astronomical Observations

• The New Generation of Telescopes

• Bibliography

The following sections are included:

• Masses

• Distances

• Times

• Bibliography

The following sections are included:

• Relativity, Special and General

• The Cosmological Dynamic Equations

• The Matter Dominated and the Radiation Dominated Eras

• The Cosmic Baryon to Photon Ratio

• Bibliography

The following sections are included:

• Gravitational, Electromagnetic and Nuclear Forces

• Conservation Laws

• Elementary Particles

• Universal Constants

• Understanding the Universe, and Open-Ended Process

• Bibliography

The following sections are included:

• Towards the Confines of the Universe

• Observable Data and Big Bang Model
  • Approximately isotropic distribution of galaxies in space
  • Universal recession of the galaxies
  • Relative abundance of ⁴He and other primordial light elements
  • Cosmic background radiation

• Implications of Contemporary Cosmology

• The Physical Universe and its Creator

• God and the Scientists

• Bibliography

To begin with I would like to point out that we can look back in time by looking at things that are very far away. We simply use the fact that light comes to us at a definite speed and so, when we look at the sun, we see the sun as it was 500 seconds before we look at it; when we look at something in the middle of the galaxy we see it as it was 25,000 years ago and when we look at something extremely far away we can see it as it was 15 billion (10⁹) years ago.

The following sections are included:

• Introduction

• COBE Mission

• DMR Instrument

• DMR Limits on Potential Systematica

• DMR Observations

• DMR Result Discussion

• DIRBE Measurements

• FIRAS Instruments Descriptions

• FIRAS Measurements

• FIRAS Interpretation

• Summary

• Bibliography

The following sections are included:

• Introduction

• Radiation/Matter Equality Temperature

• Atom Formation

• Concluding Remarks

• Bibliography

From the most remote times men have felt the fascination of the starry night and have noted with astonishment the regularities which characterize the motions of the Sun, the Moon and the Planets through heaven. We are entitled to say that astronomy is the most ancient pure science, and, like many other pure sciences, it found soon practical applications, as making calendars, useful to organize agricultural work, to register the chronicles of past times, and to do plans form the future.

The Universe as it appears now is basically homogeneous and isotropic, therefore with spherical symmetry; the constituent galaxies are moving radially away from each other with speeds proportional to the distances between them, with a local specific expansion rate given by ; this fact together with the estimated age of the oldest stars in our galaxy (and those in other galaxies), which is of the order of t₀ (the time elapsed since the Big-Bang) allows us to determine a well defined origin in time for the cosmic expansion; the relative abundance of ⁴He, and other light elements (which have a “primordial” origin) allows us to put a specific bound to the cosmic expansion rate at the time of the ⁴He nucleosynthesis; finally, the present equivalent temperature (T₀) of the cosmic background radiation, combined with the ionization/formation temperature of atoms (T_af) taking place out of the preexisting plasma of nuclei (mostly H and ⁴He) and electrons (a temperature which happens to coincide almost exactly with the temperature at which radiation and matter energy densities are equal (T_eq)), allow the determination of the characteristic cosmic temperature (T₊) at which the first stars and galaxies began to exist. This temperature is directly related to the characteristic radius, (Schwarzschild radius) of a universe with a total finite mass M_u (i.e. R₊ = 2 GM_u/c²).

The following sections are included:

• The COBE Project

• The Hubble Space Telescope

• The Spacial Mission Hipparcos

• Bibliography

The WMAP (Microwave Anisotropy Probe) was launched in June 2001 in a Delta rocket, the same type of rocket in which the COBE had been launched in orbit in November 1989. The success of the COBE mission had established beautifully the blackbody character of the microwave background radiation and, in so doing, had detected unambiguously for the first time the small anisotropics which signal the formation of the first protogalaxies. The WMAP's results (rechristened with the initial W to the memory of Princeton University astrophysicists David Wilkinson, recently deceased, who was a founding member of the partnership between Princeton and NASA's Goddard Space Flight Centre) confirmed and complemented COBE's findings with unprecedented accuracy.

The following sections are included:

• Why not in China?

• Early Medieval “Natural Philosophers”

• Bibliography

The following sections are included:

• Tomas Aquinas and the Ways to God

• Roger Bacon and the Experimental Method

• Bibliogaphy

In 1277 Etienne Tempier, bishop of Paris condemned 219 propositions covering a wide spectrum of questions clearly excluding the eternity of the world (Prop. 83–91) and the perennial recurrence of everything every 26,000 years (Prop. 92). In substance the bishop of Paris was affirming rigorously the contingency of the world with respect to a transcendental Creator, source of all rationality in the macrocosm as well as in the microcosm, in heaven as well as in Earth.

The following sections are included:

• Physicists

• Chemists

• Mathematicians

• Geologists and Geographers

• Astronomers

• Bibliography

As Max Planck¹ said in said in Stockholm (June 2, 1920) at the time he received the Nobel Prize for his discovery of the energy quanta: “Numbers decide”.

The unprecedented accuracy of the cosmological data obtained by NASA's space satellites (first COBE, then Hubble, more recently WMAP) and by ESA's satellite Hipparcos have decided conclusively in favor of the Big Bang concept. It is possible now to describe cosmic events from very early times (baryon formation, electron formation, nucleosynthesis) to the all important event of atom formation (at which the universe transformed from hot plasma to a quasi-homogeneous atomic gas with minute thermal fluctuations). From there it is possible to proceed to the subsequent formation of stars and galaxies, and finally to the time at which the Sun and the Earth were formed.

The Universe has been called “mysterious” (Jeans),¹ “accidental” (Davies),² “extravagant” (Kishner),³ but, perhaps with as much or more reason it can be called “intelligible”. Today, astrophysical cosmology at least in part is at least in part capable of putting the universe in numbers.

The following sections are included:

• Glossary

• Index