This e-book attempts to convey, in as simple as possible way, the history of how the World we live in has come to be. The story to be told is all based on accepted or settled Science, unless otherwise explicitly noted.
Before delving in the subject it is important to make a number of points clarifying the viewpoint taken by this book.
Probably the most important is that understanding modern Science can not be achieved by relying on normal faculties, i.e. common sense. Common sense, is after all what was engendered by biological and cultural evolution over eons for the former and centuries for the latter. Common sense, is therefore finely tuned to insure our personal and cultural success at the scale of events on Earth and at the size of humans and our relatives the vertebrates.
Both physics and cosmology are now exploring phenomena which can involve scales very different from the human scale. Namely, involving distances or lengths either inconceivably larger or smaller than our customary measures (feet, yards, meters, miles, kilometers). Or involving time intervals equally inconceivably larger or smaller than the customary units of seconds. minutes. hours, days, years, centuries.
Similar things can be said about ranges of: temperatures, speeds, accelerations, energies, momenta, forces, etc..
However, in the last three centuries mankind has succeeded in creating a number of techniques for transcending the limitations of our common sense. The techniques rely on the twin legs of increasingly sophisticated mathematics and experimental verification. Fortunately this does not mean that a presentation of these matters has to rely on extensive use of mathematics, but it does mean that any attempt to understand relying solely on intuition or common sense will fail.
The second point is that in talking about these matters one faces a dilemma, in so far, that if one is very scholarly and precise the prose becomes dense and unreadable, if on the other hand one greatly oversimplifies in favor of clarity and readability, one may lose too much accuracy. Fortunately, modern web (html) based techniques available to e-books allow escaping the horn of the dilemma, by a compromise. Namely, write text that gets progressively more detailed and accurate by referring to additional pages containing the added detail with required accuracy.
In particular, the approach taken is:
For the first time in history, Science can put together a complete story on how the Universe creates itself. This self creation rests on few simple but elegant concepts.
There are four forces. Namely the strong & weak nuclear forces, the electromagnetic force and finally the gravity force. These forces have different intensities and range of action. The two nuclear forces have extremely very short ranges. The other two forces are much weaker but can act over very large ranges.
There is a limited number of particles that are either acted upon by these forces or are force carriers. The interaction between forces and particles are such that the number of "free" or spontaneous transformations of a particle into another is maximized. That is the Universe is MAXIMALLY designed for spontaneous evolution.
At the instant of creation there was pure energy and unimaginably hot temperature. Through processes we do not yet grasp, the pure energy began, in part, to transform itself by creating the most elemental matter particles (quarks). The creation of quarks caused the creation of space and time. This, in turn, caused an explosive expansion of the Universe from its point source. This phase is known as cosmic inflation or just The Inflation.
The rapid expansion of space caused the energy density and temperature of the Universe to rapidly fall. Since temperature is equivalent to particle motion speed and momentum, at some point the temperature drops enough so that the strong nuclear force can no longer be overcome by the quarks motion and quarks coalesce into the more familiar particles of matter: protons and neutrons.
As expansion continues the temperature keeps dropping and we reach a point when the other matter particles (leptons: electrons & neutrinos) get created and the weak nuclear force can not be overcome by the particle motions. At this point protons and neutrons can coalesce creating the nuclei of simple atoms Hydrogen (H) and Helium (He).
As the expansion and cooling continues one reaches a point when even the much weaker electromagnetic force can not be overcome by the particle motions. At this point the electrons and nuclei coalesce and form the first few simple atoms of H & He. That is, matter, as we know it, begins to appear.
As the Universe's dimensions grow ever larger the role of the fourth and weakest force, gravity, begins to be predominant. Namely, under the influence of gravity enormous clouds H & He and other trace elements begin to form and coalesce under accelerating spin forming the early proto galaxies and eventual galaxies.
Again, under the influence of gravity, stars form from the galaxies material. Once stars form a new process starts. Namely, cooking up more complex atoms from the original H. This leads to the formation of atoms up to Iron. The remainder atoms up to at least Uranium are created during the explosion of large stars at the end of their life (supernovae).
Third generation stars (made up from the earlier generations supernovae debris) can have a rich enough collections of chemical elements that they can form rocky planets. If such a planet is in the livable zone of its star, it can have liquid water. Which is a necessary ingredient for life as we know it.
Once self replicating molecules emerge a new form of evolution appears. Namely biological evolution, which as we have witnessed on Earth, is capable of miraculous developments, given a few billions of years of fairly stable environmental conditions.
Once biological evolution reaches a level comparable to the human all new kinds of mode of evolution are unleashed. They can accomplish miraculous results in centuries or even decades, especially once the scientific method is discovered.
While, as we shall see, the future is NOT predictable, one can speculate about it. A likely speculation is that the [human] psychological development will eventually be followed by a cyborging process or what can be referred as S-biology where the S stands for silicon. This development may be characterized by S-minds (SMs) with capacities equal or possibly far exceeding ours. Such SMs might be able to exist quite easily anywhere in a solar system or even a galaxy.
One can articulate the above sketch by considering the development of the Universe to span the following phases;
Chemical: during which all the remaining kinds of atoms where created. This phase is still on 13.7 billion years after the instant of creation.
Biological: On our planet this phase originated about 9.7 billion years after the instant of creation and is still on.
Our Universe sprung to life, as a huge explosion (the Big Bang), 13.7 billion years ago. The Big Bang created both time & three dimensional (3D) space. The initial expansion of the Universe was extremely rapid. (see inflation video and the first second).
Current Science can not yet give us a definitive picture of what was happening in the first 380,000 years. At the end of that era (the Dark Ages) ordinary matter emerged, composed almost exclusively of hydrogen and helium and light was finally able to travel freely. That is, the Universe became transparent.
Present Science (2012) can give a very clear and satisfying picture of all the cosmological, stellar, planetary and biological evolutionary processes since that time. One does not need, for the time being, to know the processes of Nuclear and Atomic evolution in order to understand the Universe's evolution from the Dark Ages to the present. However familiarizing one self with them will reveal how finely balanced and awesomely elegant our Universe is.
The particle physics principles together with the following points:
Let us sketch the processes taking place between the initial Big Bang and the emergency of Chemistry (atoms and molecules) as follows:
The modern particle accelerators (LHC & RHIC) have recently managed to create matter in the Quark Gluon Plasma (QGP) state. This state of matter is a very hot (a couple of trillion degrees Fahrenheit) and a very fluid liquid made up of free quarks and gluons. This fluid was produced by smashing together gold (Z = 79 n = 118) or lead (Z = 82 n = 122) nuclei. These nuclei are quite heavy respectively 197 and 204 hadrons each.
Once droplets of this special substance are available for investigation a lot will be discerned about this phase of the early Universe.
The next phase starts after about 380,000 years, at this point the temperature has dropped enough so that the electromagnetic force can restrain the electron's thermal motion and electrons are no longer yanked out of the atoms. That is, nuclei acquire stable courts of electrons. This implies two things: a) stable chemical structures can begin to arise, b) the Universe becomes transparent since the electrons do not form an agitated cloud in the way of photons. This is the first light we now see with satellites such as WMAP.
The first light signals the beginning of the chemical phase of the universe's life. During this phase, which is still with us, the nuclear reactors we call stars, produce atoms more complex than H & He.
The chemical properties of an atom are determined by the number (Z) of electrons and their configuration. Z is also the number of protons in the atom's nucleus.
The electrons are located in concentric shells that can accommodate a limited number of "positions" (these are standing waves). The first three have respectively 2, 8, 8 positions. These correspond to the first three rows in the Periodic Table.
The metals H, Lithium, Beryllium, Sodium (Na), and Magnesium are elements which have one or two electrons in the outer shell so they can easily give them to elements which have "holes" in their outer shell. That is, Oxygen,Fluorine, Sulfur and Chlorine,
This sharing of electrons forms chemical bonds among atoms. The above reactions between the "metals" and the above alkaline bases form simple molecules which are known as salts.
The metals can also let electrons "flow" i.e. they are good conductors.
The intermediate elements Carbon & Silicon have four electrons out of eight positions in the outer shell. They can, therefore, be either donor or receiver of electrons. It is, thus, not surprising at all that both of them, and especially Carbon, have a very rich chemistry. Carbon chemistry being the basis of life on Earth, and Silicon properties being the basis for our rapidly evolving information technology.
Finally the elements Helium, Neon & Argon have full shells and do not react chemically with other elements. They are known as noble gases
An accessible source information on the nuclear reactions which generate elements up to iron (Fe) and those beyond is the Supernovae video.
Copyright Ugo O. Gagliardi 2012