Cosmogony,
Cosmic Evolution, Earth
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Cosmogony, Energy, Forces, Laws, Particles,
Quantum Mechanics
.
Quasars, Black Holes, Galaxies, Stars, Supernova
.
Earth, Moon, Plate Tectonics, Oceans, Atmosphere,
Climate, Catastrophes
.
* * *
This essay is only Part 1 of a larger essay.
Read the full essay by going to “Evolution: Understanding Physical and Mental Existence”
That essay is now available in the following separate sections:
1. Cosmogony, Cosmic Evolution, Evolution of Earth (this essay)
2. Origin of Life, Molecular Biology, Natural
Evolution, Humans
3. Origin, Evolution, and Function of the Human Mind
4. Origin, Evolution and Functions of Societies
and
Cultures
5. “Intelligent Design Theory” as opposed to
Natural Evolution
6. Extraterrestrial Intelligence?
What could it Mean to Us?
7. The Future and Expected End of Mankind and
the Universe
8. Closing Comments and Conclusions
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*
Content
of this essay: “Cosmogony, Cosmic
Evolution, Evolution of Earth”:
.
Introduction
.
1. Cosmogony, Cosmic Evolution:
1.1.
Cosmogony, Abstract Beginnings
1.2.
First Surprises: Granulation, Strings, Subatomic Particles, Forces -
Diversification and Complexity Arise. The Miracle of Existence.
1.3. Next Surprises: The Combinatorial Principle, Evolution Begins:
The Origin of Atoms and Molecules.
1.4. Order or Chaos -- Deterministic or Open-Ended?
1.5. The "Basic
Principle of Evolution"
1.6. Collapsing Clouds: Quasars, Black Holes, Galaxies,
Stars
1.7. Formation of the Heavy Eelements
1.8. Supernovae, Heavy Dust, Pre-organic Molecules:
Foundation of the Next Step
1.9. The Principle of "Limits in Development and Branching
Progress":
The Origin of Planetary Systems,
Our Own Solar System
1.10. Some Remaining Mysteries of the Originating Universe
.
2.
Evolution of Earth
2.1. The Origin
of Our Earth
2.2. The Origin of the Moon
2.3. The History of Earth
2.4. The Early Oceans, The Early Atmosphere, and Climate
2.5. Resilience in Great Catastrophes
2.7. Singularities in Earth's Evolution
.
.
Introduction:
.
When we pause for a moment in our busy life – at lunch, during a holiday, on vacation – we can perceive the wonderful and sometimes cruel existence we live in – the universe, nature on this planet Earth, our surroundings, our body, our mind. In trying to understand this existence, we find that everything in our world is evolving – has always been evolving and will continue to do so. If we want to understand our existence, we should attempt to understand this evolution.
.
Not too many years ago, one of the early NASA space projects provided the very first and rather beautiful pictures of Earth as seen from outer space. Astronomic telescopes had already provided excellent pictures of distant galaxies. Now we could visualize how our own “Milky Way” galaxy would look with the tiny spot of our Sun as one of a billion others somewhere in its outer reaches – and a still smaller, blue planet, "Earth”, whirling around that tiny sun – about four billion times already since its appearance. That small Earth is our only home, but our brains that evolved only a few ten thousand years ago allow our minds to span the universe in time and space. What were the starting conditions, principles, laws, and forces of nature that let this evolution occur?
.
Recent progress in astronomy has taught us how our universe originated in one spot some 14 billion years ago and has been expanding in all directions ever since. What happened in time and space that, out of the original burst of energy at that time, finally we humans, with all our exceptional talents, came to exist and live on this tiny planet where we now are – and to develop the mental capabilities we now have?
.
A few key aspects of Creation and evolution appear to be fundamental to the understanding of what occurred. They are especially surprising and impressive [1].
.
Come along on
a mental voyage – to explore the existence which we live in – from the
vastness
of the universe to submicroscopic molecular life, the virtual phenomena
of the
mind, and unfolding civilizations – from an origin in the distant past
to an
expected end in the distant future!
.
.
1.
Cosmogony, Cosmic Evolution:
.
1.1. Abstract Beginnings
.
What can be seen as the essence of “existence” in space and time? According to one perspective, “difference” is the essence of space, and “change” is the essence of time. Without difference in at least one parameter in at least one dimension – whether density, color, or anything else – there would be no definable space. And without change, there would be no definable time.
.
The scientific understanding of the ultimate origin of our universe is shrouded in abstract speculations, none verifiable by observation. The various scientific theories of origin mainly attempt to render unnecessary the religious or traditional “ex nihilo” (from or out of nothing) assumption of Creation and to present a precedent situation leading to the Big Bang in an understandable way, consistent with the observations and structure of the universe after the Big Bang.
.
There are various problems with this approach. The (possibly assumed) precedent situation only leads to another question of its beginning, thereby merely shifting the original question of origin to an earlier time. Otherwise, a perpetual, cyclic or ongoing sequence or multiple creative starts in the form of other universes originating out of a super-universe have to be assumed, stretching indefinitely into the past – thereby assuming time without a beginning.
.
This model still leaves us with the question of how the infinite cyclic or ongoing sequence of the super-universe – if it has not existed “forever” – was ever established. There are various theories of this genre. Earlier theories considered the effects of imaginary time or the spontaneous appearance of our universe through quantum mechanical effects [2]. Another theory [3] proposes a multitude of universes, as bubbles following each other, possibly several in parallel – like the “fractals” of chaos theory. A newer theory [4] is an outgrowth of “string” theory and posits the perpetual repetition of “branes” in multidimensional space touching each other as starting points of new universes every time one of them cools off in infinite dissipation.
.
The most commonly accepted theory at this time, one also derived from string theory and the recognition of “inflation”, visualizes a super-universe with an almost limitless variety of possible individual universes, all possibly quite different from each other (dimensionally, and in character) [5], totally unrelated to ours – thereby allowing no connection or exploration [6]. This theory still leaves the question of the specific origin or all those universes and their specific structure unanswered. More or corrected theories may be presented from time to time [7].
.
Most people, however, hold a basic transcendental belief [8] concerning the ultimate cause of creation of our universe, or of any other universe, or of a “multi-verse” – specifically in view of the finely tuned forces, natural laws, and basic constants that let our universe appear as a highly intellectual composition. This belief assumes a transcendental force, not simply a physical force, or a higher intelligence or a “spirit” as the ultimate base of existence. The assumption of a transcendental force or spirit is considered to be “religious”, while the other assumptions are considered “scientific” speculations of theoretical or mathematical physics.
.
There is actually little mental difference between the views of “religiously believing” and “scientifically assuming”. Both are based on mental assumptions that are provable only by their perceived effect in the universe – but both look at the same universe. Such observations often are, but should not be, arbitrarily selective, especially the religious ones. They can lead to a variety of contradictory theories, depending on the selectivity of their observation. All such theories can serve as the foundation for mental systems of thoughts and interpretations of the universe – only that the “transcendental” view allows an originating cause to be more than just a “physical” phenomenon, even more than just an “intellectual essence”, one possibly including the dimensions of emotions (love?), ethics, values, aesthetics, and other dimensions that are fundamental to our minds and cultures and that usually are not the key concern of the sciences in cosmogony.
.
It is a matter of the now very active discussion of “Science and Religion” to elucidate to what extent the factual observation of the universe justifies, or does not justify, a transcendental assumption concerning the origin of the universe [9].
.
It is quite a different matter to then also assume, or prove, any further action of such spiritual force of origin in the subsequent evolution of the universe (see Chapters 3.1.2 and 3.3), the possible responsiveness to personal prayer, and the divine setting of moral standards – unless one sees those moral standards as anchored in human nature and, thereby, in evolution – and, therefore, in the foundation of Creation and, by this roundabout way, in its possible transcendental essence [10].
.
Irrespective
of all these considerations, the original energy bursting out of the
Big Bang,
still not structured into particles in its beginning, can be seen only
as
energy “fields” of very high power in a small space.
Fields of energy are nothing material – yet,
something real – existing in the emptiness of space – in the
nothingness – in
the vacuum. How
can emptiness or nothingness
– the vacuum of space – harbor fields?
What are fields held by emptiness?
.
One cannot leave the discussion of the origin of our universe without marveling at another aspect of this universe: The originating universe exhibited the phenomenon of constantly flowing time (not slowing down, not accelerating, but always flowing at a constant rate in the vastness of the universe over the past 14 billion years – at least as far as is inferred from observations [11]) and had three dimensions of space (not two, or four, or any other number [12]). The fact that time flows at a constant rate for any one observer, but appears to flow at different rates for observers moving relative to each other (and possibly stops in “Black Holes”), renders this phenomenon all the more mysterious [13]. Additionally, there is the quantum-mechanical surprise that there is no smaller time increment than so-called “Planck” time.
.
The fact that our universe is governed and constrained by forces, laws, and principles of nature –and, therefore, functions in an order that can be described by mathematics or theoretical physics – is another mystery of origin. It is specifically this “intellectual” character of the universe that can be seen as pointing to a transcendental origin, foundation, or essence of the universe.
.
Another “miracle” of Creation occurred within the first fraction of the first second of existence – a short inflationary period of the originating universe. At that early time, the energy ball that constituted the infant universe expanded from negligible size to approximately the size of a baseball. The expanding space itself mysteriously provided a very large amount of additional energy and the expansion speed was a multiple of the speed of light – while afterwards, the speed of light was found to be the highest speed that can possibly exist in nature.
.
There are new theories that take this inflationary period into account. Some scientists are inclined to think that such theories, properly representing the occurrences in nature, are expressions of the originating force. One must be somewhat careful with such a posteriori statements. For example, one cannot say that, since the new theories allowed the inflationary period to happen, it must have happened. If the occurrences had been found to be different, science would have found a mathematical presentation or theory to represent the universe accordingly. In other words, not the theories drive the world but what the world is found to actually be leads to suitable theories – theories that often change quite dramatically as new insights are gained concerning the workings of the universe [14].
.
.
1.2. First Surprises: Granulation: Strings, Subatomic Particles, Forces –
Diversification and Complexity arise. The miracle of existence
.
As the Big Bang occurred, the original energy – as it expanded in space and time – quickly assumed some structure – by partially “condensing” into a variety of subatomic particles [15].
.
There are several surprising, and very significant, aspects of this first phase of cosmic formation:
- The original energy of the Big Bang did not expand as one big wave – as, for example, the wave that forms and expands around a pebble that falls into a quiet pond. Instead, a large portion of the original energy broke down – granulated – into extremely small, discrete parts that filled the originating space.
- Not only one type, but a limited, diverse set of different strings or subatomic particles occurred – where “strings” can be visualized vaguely as short energy waves – like tiny multidimensional or circular energy waves concentrated in one point and oscillating at different frequencies.
.
Modern science
can prove the necessity for the formation of subatomic particles and
could even
predict which new ones are yet to be found.
But one should be careful with this view. As
is said above, it is not the theory that
forces nature to exist in a certain form.
When nature is understood, theories become formulated that best
describe
its appearance. As new knowledge is
gained, theories are changed until they fit.
The miracle still lies in nature, not in the theories – unless
one
considers the fact that nature can be
understood and described by certain
mathematically formulated theories as a miracle in itself, as well as
an
indication of its intellectual character, some would say, its
“spiritual”
essence.
.
Scientific research has found three groups of subatomic particles, each with a certain variety of members:
- Quarks (or “hadrons”): Commonly, six different types are indicated. But it has been proposed that there are actually only four or five different types, all with unusual names (“up”, “down”, “strange”, “charm”, and “bottom”). Two of them make up most of the material universe. The other three have an unstable, short-lived existence.
- Leptons: Some members of this family are better known (“electrons”) than others (“muons” and “taus”), and all have associated “neutrino” particles.
- Bosons: These subunits of the universe serve to transmit forces. For example, the transmission of “W bosons” provides the action of the “electro-weak force”. The “gluons” function as the transmitters of the “strong force” that can bind quarks together.
.
All together, there may be a couple of hundred different basic particles. More important is the fact that, for each type of particle, there exists a type of “anti-particle” with an equal amount but opposite kind of energy, such that a combination of the two would neutralize or annihilate both. The newly created universe appears to have produced an asymmetrical amount of those two types, allowing the existence of the world as we know it after most opposite particles annihilated themselves and only the not-matched ones were left over. The resulting “matter” makes up about 5% of our universe – half of this located in all the galaxies, the other half expected to be in some large intergalactic clouds of hot gas, as recently discovered. This figure may possibly have to be corrected upward by a large percentage (up to 18% has already been reported) if the mass and also the number of brown dwarfs and smaller stars, which already constitute possibly more than half of the mass in the galaxies, are both confirmed to be larger (possibly by a factor of two).
.
Another large part (maybe 25%) of the original energy of the nascent universe condensed into “dark matter”, not visible and little understood so far, but possibly forming the bulk of all galaxies. Finally, there is the recently discovered “dark energy”, accounting for the remaining 70% of the universe, understood as part and expression of space in the universe and responsible for driving the galaxies apart at increasing speed. It is still a mystery how space can harbor forces and provide the gigantic energy for all the galaxies’ acceleration. The figures for the dark matter and dark energy would have to be corrected downward if the percentage of normal matter is corrected upward.
.
A small remaining part of the original energy – the part that did not form discrete strings and particles or dark matter and dark energy – remained in the form of radiation – that ever since has moved around in the created space.
.
It is
a special mystery of the origin of existence that the particles
resulting from the original energy – the strings or subatomic particles
– exhibited
various types of forces that emanated out into space – the
electromagnetic forces, gravity, and certain atomic forces,
each very
different from the other. Those forces
became responsible for giving structure to the
existence we live
in. The atomic forces structure all
matter by keeping the subatomic particles together in the atoms while
also
keeping different atoms apart. The
electromagnetic force structures the protective field around Earth and
provides
us now with electric energy, light, and communication, including the
internet. The gravitational force, small
as it may be between atoms, is the gigantic force in the universe that
structures galaxies and solar systems. No
particle is fully independent in the universe.
.
All these forces emanated at a certain speed, the “speed of light”, through the empty space that separated those particles from each other. How can forces exist between particles that are themselves combinations of “strings”, of fields in space? Only a limited set of different forces occurred between particles. That specific set and no other forces determined the course of the world ever since.
.
In other words, all of existence – all energy, specifically also all matter, all radiation, and all forces in the universe – in other words, all phenomena that we perceive as constituting the reality of the universe – are merely fields in the vacuum – absolutely abstract phenomena of empty space. When we touch things, we merely sense the repulsive forces between approaching “strings” that constitute what we call “particles.” When we see things, we perceive only the electromagnetic radiation that was emitted, modified, or deflected by combinations of “strings”. That is all there is in existence – fields!
.
It is a mystery how empty space can host fields or forces, how these fields and forces can be propagated by the vacuum at a precisely given speed, and how they can form all there is in the universe – the celestial bodies, us, and our brains providing our minds.
.
Furthermore, some of the subatomic particles – though composed only of energy strings in the vacuum – exhibited the effect of “mass”, requiring force for acceleration and showing “momentum” as they move along. Mass can be understood as a form of concentrated energy and can be transformed back into radiation – as in Einstein’s law, e = mc2, where the dissipated energy “e” is equal to the product of the mass being dissipated and the square of the speed of light – just as the dynamic energy of a moving object is the product of its mass and the square of its velocity – as when something hits you. It is a mystery how an accumulation of strings or subatomic particles – energy waves or field accumulations in the vacuum of space – can have “mass” with inertia.
.
Was it inherent in the original energy of the Big Bang that this structure of particles and forces had to occur, or is there a two-aspect creativity – two different concepts of Creation – of energy and of structure – of power and of controlling laws – that resulted in the structure of the universe – miraculously understandable to us (in part) by the mathematics of theoretical physics?
.
The fact that several different types of particles and forces appeared out of the original burst of energy is the first demonstration of nature’s principle of diversification – and increasing complexity – later to be found throughout ongoing evolution. It is bewildering how many types of subatomic particles appeared and how complex their interaction is. Some few particles may account for the majority of what we perceive as the material universe, but all types of particles are needed and all types play their role to form the universe we know.
.
As if the above view of the originating universe – with all its field effects in the vacuum, its multitude of particles, and its various forces – were not mysterious enough, one must additionally consider the findings of quantum mechanics or quantum physics.
- Planck found in 1900 that not only all matter, but also all energy is “granulated” into discrete quantities of energy of multiples of a basic “action quant” – confirmed in 1905 by Einstein. Planck also found the duality of light as existing both as wave and as particle – later expanded to other subatomic particles by Schrödinger.
- Pauli, in 1924, discovered the “exclusion principle” – whereby no two sets of quantum numbers defining the energy state of the particles in an atom, molecule, or “fermion-accumulation” can be alike.
- Uhlenbeck and Goudsmit brought the discovery of “spin” in electrons in 1925.
- In 1927, Heisenberg presented his “uncertainty principle”, indicating the probabilistic nature of all particles in the dimensions of space and momentum. Ultimately, this led to the recognition that some particles and their anti-particles may appear spontaneously in space in a probabilistic distribution – and annihilate themselves again.
- Later, some scientists were led to the assumption that the origin of our universe could have been a quantum-mechanical event.
- Hawking arrived at the conclusion that “Black Holes”, the ultimate form of celestial bodies in the dying universe, can become dissipated over long periods of time – through asymmetric absorption of such spontaneously generated particle pairs on the black hole’s surfaces – leaving nothing but dispersing radiation in an ever-expanding space.
- This insight of uncertainty or indeterminism – together with chaos theory, whereby even the smallest variation may cause the greatest consequences – resulted in a breach of the Laplacian determinism as a basic understanding of the universe. (The deterministic character of the wave aspect of particles remains but within a probabilistic distribution for the particle represented by the wave).
.
In sum, there were the following creative aspects of the origin of existence that one must see as having appeared together:
- The appearance of energy
- The spreading of the original energy in appearing space and time
- The granulation of energy into “strings” and subatomic particles
- The appearance of forces that provided for structures
- The appearance of natural laws (and principles and constants) that provided for the dynamic evolution of the universe in time
- The combinatorial principle allowing for the emergence of new and ever higher dimension of existence
.
What
a strange world this universe is that we now inhabit!
.
.
1.3. The Next Surprise: The Combinatorial Principle, Evolution Begins:
The Origin of Atoms and Molecules
.
As the originating universe cooled due to its expansion, the “subatomic particles” began to combine, thereby forming a variety of larger “atomic particles” – mainly neutrons (without an electric charge), protons (with a positive electric charge and consisting of three quarks), electrons (much smaller particles, with a negative electric charge, consisting of leptons), and the particles that form the little-understood, so-called “dark matter” of the universe.
.
Some of these “atomic particles”, in turn, combined to form a variety of “atoms”, the building blocks of the many chemical elements, resulting in 105 types [16] or “elements” of increasing atomic size in total. These “elements” became the building blocks of the universe. Finally, some of the atoms combined to form the first miniature “molecules”. The accumulation of these molecules later formed the various materials in this world – from air, water, and minerals to all the organic substances.
.
In each step, the forces between the smaller particles determined the structure of the newly emerging larger particles.
.
These three steps – the appearance of the different types of atomic particles out of the combination of subatomic particles, then the emergence of atoms, and finally the emergence of molecules out of atoms – are the first demonstration of nature’s “combinatorial principle”. This principle indicates that nature allows for the combination of smaller building blocks into larger ones which then assume totally new characteristics – new dimensions of existence – that were not observable with the smaller building blocks [17].
.
A pile of toy marbles remains just a pile of toy marbles. But if a pile of neutrons, protons, and electrons had always stayed a pile of neutrons, protons, and electrons and had not formed atoms – or a pile of atoms had always stayed just a pile of atoms and had not formed molecules – the world we know could not have developed.
.
For example, the atoms constituting the elements hydrogen, calcium, and gold are something descriptively altogether different from neutrons, protons, and electrons of which all of them are combined – just in different configurations. The descriptive nature of molecular water (combined out of 2 atoms of hydrogen and 1 atom of oxygen), salt (combined out of 1 atom of hydrogen and 1 atom of chloride), and sugar (a combination of 6 atoms of carbon, 6 atoms of hydrogen, and 6 atoms of oxygen or a multiple thereof, depending on the type of sugar) are different in their principal characteristics from the elemental atoms of which they are composed.
.
This becomes even more apparent when considering the very large and complex organic molecules that make up the living organisms composed mainly only of atoms of carbon, oxygen, hydrogen, nitrogen, phosphorus, and sulfur – plus some trace elements.
.
This phenomenon of the combinatorial principle can be compared to the use of bricks to build a cathedral or electronic components to build a computer – the combination of letters to form words and of words to form sentences – or the combination of basic elements of knowledge and perception to arrive at new concepts or systems of thought.
.
The three phenomena of Creation, the granulation of the original energy of Creation providing the first building blocks and the forces acting between them, plus the combinatorial principle that allows their ongoing combination to ever larger and different units of existence, are the foundation of the phenomenon of evolution that brought us the world we now inhabit.
.
.
1.4. Order or Chaos – Deterministic or Open-Ended?
.
It is important to note that the expanding universe – in its distribution of energy, radiation, and particles within the expanding space – showed, for reasons unknown, a large degree of randomness in density distribution. A three-dimensional model of the universe at our time would look like a sponge – with certain bubble-like spaces containing almost no stars, galaxies, or dust clouds – and other spaces containing “filaments” and knots of accumulations of matter in the form of stars, galaxies, or dust clouds – all in a random arrangement like a sponge.
.
In other
words, the essence of the expanding universe demonstrated a duality of strictly following
the laws and principles of nature, while also containing large areas of
randomness – a duality of order and
freedom.
.
This duality can be observed much closer to our sphere of life. The stars in the sky appear in a random distribution – though in their movements strictly following the order prevailing within the galaxies in the universe. The surface of an ocean, seen from a great altitude, appears smooth and following the round shape of the surface of Earth. From up close, the ocean is covered with a random distribution of waves. An approaching snow storm may appear as a cloud with a given shape, but within it, the distribution of snowflakes is totally random – each having a well-defined geometric shape as given by the laws of crystallography.
.
Thus it
appears as if spheres of strict order in
accordance with the laws of nature are
superimposed on, or alternating with spheres of randomness or freedom
within
the structure of the universe.
.
This duality
of order and randomness not only allowed the
evolution of a large variety of
structures, but also made future development of structures not-deterministic,
unpredictable in detail, and, at best, probabilistic.
.
Equally important for all later development is the duality between normal physics and quantum mechanics resulting in the duality between deterministic predictability of large-scale events and probabilistic, non-deterministic phenomena on the atomic level leading to unexpected developments. In other words, development does follow the laws and principles of nature – but also includes the indicated background randomness of the universe and the uncertainty of quantum mechanics. Chaos Theory shows how minute differences in detail can result in major changes of the overall system.
.
.
1.5. The “Basic Principle of Evolution”
.
The probabilistic variations and random events in the universe result in an evolutionary thrust in evolution [18]. Actually, there are the following elements to be found in an evolutionary step:
- The starting conditions define the character of a potential step in evolution
- The boundary conditions may limit the evolution; but, more important, they may indicate new options for viable evolution
- Probabilistic variations allow a gradually different relation to the boundary or environmental situation and, thereby – if viable – may offer a step in evolution
- Random events may allow for radically new approaches in evolution
.
With probabilistic variations and random events occurring at all times, there is an ongoing thrust for further evolution – occurring as starting conditions and opportunities permit.
.
This will be discussed in greater detail in the chapter on the natural evolution of life, where this “Basic Principle of Evolution” becomes most significant and best observable, as high propagation rates and limited resources or adversity augment the evolutionary pressure in the sphere of life.
.
The sum of this principle and all observations indicates that:
-
The universe is not
developing in accordance
with a plan and converging on a goal
-
Instead, the
universe evolves in steps as
possible at any one time or place in accordance with the then and there
given
starting and boundary conditions – with evolution being driven by
probabilistic
or random variations, and finding viability in accordance with
opportunity.
.
Therefore, all evolution – in each of its steps – is not end-point conditioned or goal-attracted, but is starting-point conditioned (for each step) and forward-directed. Thereby, evolution remains open-ended within the limits of opportunity [19]. This will be discussed in more detail in connection with the progress of natural evolution.
.
.
1.6. Collapsing Clouds: Quasars, Black Holes, Galaxies, Stars
.
As the nascent universe formed enormous clouds of particles, some inherent instability became apparent. A diversity of phenomena resulted from that.
.
The original atoms or molecules in the so-called gaseous “dust clouds” were attracted to each other by gravity, weak as those forces were for each atom alone over large distances. The high temperature of those clouds – indicating the high speed of the individual particles – did not allow the dust in those clouds to coalesce or “accrue”. But the gaseous dust clouds cooled by means of radiation (natural emanation of radiation), and, in the areas of highest concentration of those clouds, the probabilistic motion of the particles could lead to probabilistic accumulations. Such accumulations – after some cooling – had, finally, higher gravitational attraction than the heat-related dispersion.
.
Once a nucleus
of many particles had been formed, their accumulated gravitational
force
increased and ever larger amounts of particles were attracted. Thus, an avalanche of
large accretions of matter
could form, as permitted by cooling.
Such gravitational collapse of gaseous dust clouds could take
diverse
courses. The most
notable ones were the
formation of quasars, Black Holes, and
galaxies.
.
Quasars:
Their characteristics are:
- Relatively small size of these celestial objects (only about one light-year in diameter, while galaxy diameters are in the hundreds of thousands of light-years)
- Enormous luminosity (about 1,000 times the luminosity of a large galaxy)
- Mostly formed in the first 2 billion years of the universe
- Explained as the formative processes of Black Holes
- Their radiation resulting from the gases falling as an avalanche at high speed into the respectively forming new black holes
.
Black
Holes:
The “stellar”
black holes are understood as resulting from the avalanche-like
collapse of
dense clouds of dust in a single point (small area) whereby, when large
enough,
such enormous pressures are created at the center of the collapse that
the
phenomenon of “Black Holes” was created, a gravitational concentration
of such
size that not even light could escape such a hole any longer.
.
To understand
this phenomenon, one must consider that the
nuclei of atoms have only
.
“Galactic” or “quasar” black holes form at less pressure or density, but with the same effect.
.
Galaxies:
A collapsing cloud of dust – at first a giant ball of dust with higher concentration at the center – ends up forming a disk. This results from any spurious rotational momentum in the part of the cloud that was collapsing. As when rotating ice skaters hold weights in outstretched hands and their rotation accelerates as they retract the hands with the weights, the collapsing clouds rotate faster as they collapse (in accordance with the natural law of “the conservation of angular momentum”). Actually, each attracted particle will rotate on a differently inclined plane around the center; but the intersecting planes will lead to realigning collisions until all parts find themselves in the plane of the original cloud rotation – in a disk.
.
Further
gravitational collapse of such a disk – after cooling due to the
emission of
radiation – can permit the formation of a
small core – later to
become a black hole when the pressure in the core and its mass is high
enough. Some theories propose the
opposite sequence, with the formation of a
black hole first and
subsequent attraction of masses of gas around it.
.
For reasons that are not fully understood, the dust disk around many galaxies shows mostly two (estimated to be in more than 60% of galaxies), but sometimes three, spiral arms of accumulated star formation. In many large galaxies, the spiral arms bifurcate, resulting in 4 to 6 branches in the outer areas. This spiral pattern rotates around the galaxy’s core (at a different rotation rate from that of the stars). Occasionally, a large central ring and, more often, a central bar can be seen in the galaxies, sometimes rotating at a different speed, sometimes with arm protrusions from each of its ends (e.g., galaxy NGC 1087 in the constellation Cetus). One theory of galactic evolution assumes that avalanche effects in the collapsing proto-galactic dust discs form gigantic shock waves circulating around the center of the galaxy-to-be. Actually, the spiral arms of galaxies do not wrap up tightly – rather, they keep their pattern and look like rotating sprinklers, like effects emanating from the rotating center, possibly having something to do with the shock waves emanating from black holes at the centers of the galaxies [20]. The presently prevailing theory sees “resonances” in the stellar orbits as the cause for the spiral arm formation [21].
.
Galaxies come in a large variety of shapes (round and elliptical, flat or with a central bulge) or sizes. The smallest discovered so far is Andromeda IX with only 3,000 light-years diameter, at a distance of 2 million light-years from our sun (see www.SDSS.org). Other very small ones have already merged or are in the process of merging with our galaxy, the Milky Way [22].
.
Stars:
Those shock waves in the galactic disks are thought to cause new accretions in the galactic dust clouds, but on a smaller scale. The resulting smaller dust disks also form concentrated centers. Those are the ones that become stars when their mass, inner pressure and temperature allow thermonuclear reactions to set in. Therefore, these newly formed centers that became stars light up, letting the luminous spiraling arms of the galaxies appear [23].
.
There are by now approximately 100 billion stars in our galaxy, the Milky Way, with more still forming while there is interstellar dust left over [24].
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The largest stars are the brightest and have the shortest period of light emission – only in the 100-million-year range – and end in an explosion as supernovae. There are about 10,000 supernovae per million years in our galaxy. That translates into 500,000 supernova explosions per spiraling arm per revolution of that arm at the distance of Earth from the center of the galaxy. The supernova explosions past the edge of the star-forming spiral arms circulating the core of galaxies may contribute to the propagation of these as shock waves, like a cosmic ram-jet.
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The smaller stars, like our Sun [25] – with a light-emitting life of about 10 billion years – leave the shock waves or arms of the galaxies, thereby also leaving the area of the most intense and destructive radiation resulting from the supernova explosions. This fact is important in the evolution of life on planets of such stars. Our Sun with its planets is assumed to rotate once every 220 million years around the center of our galaxy, the Milky Way.
.
On a clear night, one can see a multitude of
stars and
galaxies. A good telescope allows seeing
a still greater quantity. Actually,
however, the universe is mostly empty space. If one were to build a model of the universe
in which the Sun had a diameter of only 2 inches (5 cm), Earth would be
about
15 feet (5 meters) distant from it and would have a diameter of less
than
1/64th of an inch (0.5 mm).
Correspondingly small and widely distributed would be the other
planets
in empty space. The next solar system to
ours would be at a distance of more than 500 miles (750 km). In between, there would be nothing but empty
space, even where we are, right within the disk of a galaxy, in our
Milky
Way.
.
Between the distributed galaxies there is, again, nothing but expansive empty space. The galaxies are distributed in the universe much like the material in a sponge. There are accumulations of galaxies in some clusters, as well as a multitude of ribbons of galaxies on the periphery of gigantic bubbles of almost empty space.
.
This exotic structure is in slow motion in consequence of the ongoing expansion of the universe, gravitational forces, and other causes for the motion of galaxies, occasionally leading to their collision. Our Milky Way is expected to collide with the galaxy called the Andromeda Nebula in some billions of years [26] as it may have collided already with some smaller galaxies in the past (that may have provided the star belt around the Milky Way).
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.
1.7. Formation of the Heavy Elements
.
After the Big Bang, the majority of the atoms formed in consequence of the above-explained “combinatorial principle”. They were of the smallest kind, mostly just hydrogen and some helium, composed of one or two neutrons, one or two protons and one or two electrons.
.
When sub-segments of galactic dust disks – the forerunners of galaxies or their later companion gas cloud – collapsed, as indicated above, they formed small cores, the future stars. These cores came in different sizes as they formed the stars-to-be. Consequently, the compression and heat in the centers of these developing stars varied according to their size. Within the medium-size stars, the pressure and heat were enough (at about 10 million degrees Kelvin or C) to weld several hydrogen atoms into larger helium atoms – the same transformation that occurs in atomic hydrogen bombs. The excess energy appeared as the bright radiation of such stars. This occurred to our Sun.
.
As this atomic transformation within our Sun continues, it becomes more intense. In another 2 to 3 billion years, shortly before all hydrogen is used up to form helium, the Sun will further heat up, as it has done in a minor way during all of its life – then rendering all life on Earth impossible. At the very end of the cycle, in 4 to 5 billion years, the Sun will have enlarged enormously, its gaseous edge reaching the path of Earth, while its glow will be reduced to a dark red. Then, as the heat is dissipated and no new heat is generated due to lack of hydrogen to be transformed into helium, this “Red Giant” begins to slowly contract.
.
This contraction will produce such pressure at the center of the then much smaller Sun that – combined with the heat from the contraction – a new atomic reaction will set in – forming mainly the elements of carbon and oxygen out of helium. What is left of such a sun is then a small star called a “White Dwarf” containing much carbon and oxygen – the destiny of possibly 95% of all stars.
.
The atomic burning (or construction) process of larger atoms, beyond carbon, works much faster in very large stars than in medium-size stars like our Sun, completing the life of such giant stars in only about 100 million years. In a sequence of steps, finally the relatively heavy element iron is formed, consuming almost all their atomic particles. When those larger stars collapse for the last time as supernovae at the end of the atomic process that burned all hydrogen and helium and finally formed iron, such enormous pressure and temperature occur at their center that free neutrons are formed, allowing the formation of all the remaining heavy atoms (or chemical elements) beyond iron – up to uranium, plutonium, and beyond. There is a limit, however. Larger atoms are not stable and fall apart as quickly as they are being built. This is the end of atomic evolution in astronomic or astrophysical terms. Later, in planetary development, nature forms molecules – accumulations of atoms that far exceed the size of the heaviest elements and open new approaches to evolutionary development.
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1.8. Supernovae, Heavy Dust, Pre-Organic Molecules: Foundation for the Next Step
.
When the process of forming heavy atoms in the largest stars is completed and no further heat is generated from atomic processes, gravity prevails over the dissipating force of heat. At that point, the very large stars collapse in such a fury that their implosion/explosion drives off most of the material around their core into outer space – distributing atoms of a large variety and in great quantities of heavy elements all over cosmic space. Such a supernova explosion takes place about once every hundred years in a galaxy like ours – that means 10,000 times in a million years.
.
Another aspect of such implosions/explosions of supernovae is the distribution of strong radiation into space. This radiation can lead to the formation of methane (a carbon atom linked to 4 hydrogen atoms) and many other types of proto-organic molecules out of the hydrogen, carbon, oxygen, and other elements contained in the great dust clouds in space.
.
Many of the
heavy atoms being distributed by exploding supernovae are a bit
overloaded with
atomic particles, providing some instability and the need for minor
corrections
in atomic content. This appears as
radioactivity when these atoms shed the extra particles or fall apart
into two
more stable parts. Such radioactivity
provides additional radiation that further
contributes to the formation of
proto-organic molecules in space.
.
As will be shown, new gravitational collapses – in other areas of the galaxy, forming new stars and their planets at a later time – utilize these heavy materials resulting from supernovae in their dust disks to form heavy planets such as our Earth and possibly use the proto-organic molecules for the formation of life.
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.
1.9. The “Principle of Limits in Development and Branching Progress”:
The Origin of Planetary Systems, Our Own Solar System
.
The formation of the heaviest possible (and still stable) elements in supernova-yielding stars of large mass may have appeared as the end of cosmic evolution. It seems to be a principle of evolution in the universe that all developments ultimately reach a limit when they lead to a size or complexity that results in instability – later also observable in natural, technical, or political evolution. But the surprising phenomenon of evolution in the universe consists of the fact that evolution then continues in a different dimension, on a different level, as on a new branch. At the point of development of the universe when supernovae reached the limit in producing heavy elements, this evolutionary branching occurred through the development of complexity in or on planetary systems – ultimately leading to life and the appearance of humans.
.
As already
described, collapsing segments of the dust disk of a galaxy formed
smaller
discs with stars as their massive centers.
The prevalent turbulence or rotation within the galactic disk–
that may
have caused the galactic collapse in the first place – led to a
rotation of the
small dust discs forming the stars. As
long as such a disk had low density and high temperature, further
accretion of
matter was delayed. But as such a disk
cooled through dissipation of radiation and increased in density, a
surprising
phenomenon occurred. Different from the
very large galactic discs that developed rotating “arms” or shock waves
full of
nascent stars, the much smaller discs around
stars formed discrete
bands. Those bands “accreted”
(consolidated) over time, giving birth to planets.
.
There seems to be a specific regularity of such formation of bands and of planets out of each band – most likely dependent upon the density of the disk material and the temperature (compare the formation of snowflakes out of humid air as it cools – of rather uniform size at originally similar distances – depending on temperature and humidity). There is a balance of forces in a dust disk around a nascent star. The heat of the dust and the radiation pressure from the new star drive the gas and dust outward; gravity pulls it inward. In consequence, the heavy elements in the dust disc settle closer to the nascent star in the center, and the light elements remain farther out. But the many perturbations and collisions of the coalescing masses allow some of the lighter elements and water molecules to arrive at or remain in the inner bands, including that of our Earth.
.
The developing bands in the dust disk around a nascent sun split into narrower bands closer to the star and much wider bands farther out.
.
Ultimately, a planet develops in each band, accumulating much of the material within that band. This may be facilitated by the fact that all those particles within a band do not circulate in parallel but most often on elliptical paths around the star with innumerable intersections of their paths and consequent collisions. Their motion is further complicated by the fact that each collision that varies their forward motion also results in a change of their rate of rotation around their sun and, consequently, their distance from the sun. Faster-circulating particles will move farther out and rotate slower on those wider paths, while slower particles will drop closer in on the central star and begin to rotate faster on those narrower paths. This creates additional turbulence in each band, first facilitating the narrowing of the band and then accretion in the form of a planet [27].
.
Some recent discoveries indicate that planets formed around some new stars in the “short” time of only a few million years after the origin of their respective sun.
.
Our own solar system formed in the large area of the Milky Way galaxy where earlier supernova explosions had left enough dust containing heavy elements. As this dust disk of our nascent solar system cooled enough to accrete into bands and those into planets, the heavy dust had already had time to gravitationally sink down closer to the center of the whirl around our Sun. Furthermore, the temperature of the dust disk is greater in the vicinity of the central Sun due to its radiation and the greater friction at the higher speed of rotation of the closer particles. This allows only heavier materials to accrete, driving the lighter materials toward accretion farther out in the solar dust disk. Thereby, several planets consisting of heavy material were formed closer to the Sun, while the gaseous planets – usually accreting into larger bodies – were formed farther out in the disk.
.
The formation of bands, their distance from the Sun and their width, and the distance of the subsequent planets from the center of our solar system followed closely a mathematical sequence (the Titius-Bode sequence). One will have to discover more solar systems with planets like ours in outer space to fully understand the astrophysical background of this sequence – and the probability for the formation of other Earth-like planets in the universe, possibly in large numbers.
.
The accretion of planets out of bands in the dust disk around a central sun is a rather messy affair. From the time of the original formation of the dust disc, and due to its mode of formation, the dust particles rotate around the central sun on various planes that are just slightly inclined to each other. They also move not in perfect circles, but rather on slightly elliptic courses. This leads to collisions of dust particles and, first, accretions into small clumps. At the same time, some particles, in transferring their kinetic energy to another particle or clump without sticking, will lose their rotational movement around the sun and the consequent centrifugal force. They will fall in large numbers into the central sun. Other dust particles may be excessively accelerated by impact and may fly off, out of the still accreting band at any possible angle, contributing to space dust that will possibly impact any of the forming planets of the solar system at a later time until it is wiped out of the solar system by the “stellar wind” emanating from the turbulence of the central sun.
.
As such initial clumps of accretion get larger, they begin to exert an increasing gravitational force on their environment, attracting more dust to accrete around them. Larger accretions of material are called planetesimals. They, too, can collide with each other due to their different speeds and paths, possibly leading to further accretion into ever larger bodies, finally forming a planet. But some such collisions of planetesimals can be destructive, with some particles losing kinetic energy and falling into the central sun, others possibly being thrown out of the accretion band and becoming comets. In sum, only a limited part of the original dust bands ends up in the formation of planets, with much of the material having fallen into the Sun or having been thrown off course [28]. The final rate of rotation and ecliptic inclination of the planet’s rotation relative to its path around the Sun are also influenced by those accretionary collisions and later comet or asteroid encounters. Until more Earth-like planets are discovered in outer space and their rotation evaluated, we do not know how unusual or typical Earth’s rotation is – and, consequently, the foundation of its climate, as discussed below.
.
A special case is the beginning accretion of a planet out of a band of dust between Mars and Jupiter. This band rotates around the Sun at a slightly different rate from Jupiter due to the difference in distance from the sun. Consequently, Jupiter perpetually keeps sweeping over this band. Accretion clumps or planetesimals in this band are disturbed by the passing gravitational force of Jupiter. This leads to the break-up of the planetesimals before they become too large, leaving only a band of various chunks of material, called the Asteroid Belt. It also leads to additional collisions within the band with resulting ejections that become comets. Many of the comets reaching Earth in our days result from this Asteroid Belt and many more must be expected in the future [29].
.
Comets of planetesimal origin have played an important role in our solar system. In the very early solar system, some very large ones existed (the number is believed to have been more than 10), possibly as large as the planet Mercury or Mars now is. One of those, possibly out of the same band as Earth, is supposed to have hit Earth more than 4 billion years ago, leading to the formation of our Moon, as described in a later chapter. Others have hit Earth from time to time, leading to great devastation, as also described later on.
.
The band out of which Earth developed contained heavy elements, but very little carbon or water. Outer planets (Jupiter and beyond) evolved out of planetesimals containing these materials in great quantities. It is assumed that icy comets that originated in the accretion of those outer planets – or, in later time, were part of the Kuiper or Oort Belt (see prior footnote) – contributed the large amounts of water and carbon that was subsequently found on Earth.
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Some icy comets, possibly from the formation of the outer planets, collected space dust on their surfaces through the long time of their existence in outer space. Some of that dust on their surfaces contained proto-organic molecules. These surfaces allowed further chemical changes of the proto-organic substances under the influence of radiation from the Sun and radioactive materials in space, leading to proto-organic materials of higher complexity and precursor materials of life, as also described later, possibly triggering life as they struck the Earth some 3.8 billion years ago [30].
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An preceding chapter of this essay called attention to the fact that the universe contains spheres of clear order in strict adherence to the laws of nature (see, for example, the perfect rings around Saturn) superimposed to or combined with spheres of chaotic, random, or probabilistic disorder (note the random appearance of comets) leading to an unpredictable evolution of existence. The above described origin of planets, planetesimals, and comets – and their interaction – is another such example, in this case leading to the evolution of Earth and our evolution on it – possibly to other similar or different evolutions in outer space.
.
The observation of the first extra-solar planets around other stars in our galaxy in recent time, by means of the newest and most advanced telescopes, has shown a number of very large planets of those stars on mostly very elliptical orbits. They were found in connection with about 8% of all Sun-like stars that could be observed.
.
Some comments: Only very large planets can be detected with the present means of astronomy, and only those that travel in the plane of observation (not perpendicular to it). The elliptical orbit allows those planets to sweep a large area of their respective dust disk, consequently allowing them to become quite large. What causes this ellipticity is not clear at this time – but, possibly, it is the passing of celestial objects. It is not clear whether most areas around stars are thus disturbed, leading to such large planets on elliptical orbits – and whether our solar system, with its quiet formation of near-circular bands and of consequently smaller planets, is the exception – or, vice versa, the rule.
.
Furthermore, some of the detected planets are very close to their stars. One theory suspects a migration of such planets toward the center, closer to their stars. But one could also discuss the rate of rotation of the forming dust disk. If that was very low, planets should be found close to their star – and vice versa. The question arises, again, whether our planetary system was caused by fortuitous circumstances, in this case, with a favorable rate of rotation of the originating dust disk, or what the distribution of those rates of rotation in the universe are with what consequences for star formation. NASA’s “Kepler” telescope mission (a successor to Hubble) should bring further information sometime after 2007.
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.
1.10. Some Remaining Mysteries of the Originating Universe
.
The expansion of the universe caused by the explosive Big Bang had been expected to slow down on account of the gravitational forces between all the components of the universe – the dust clouds, the black holes, and the galaxies. Much to the surprise of all scientists, it was found just recently that the universe expands at an accelerating rate. The common explanation is found in a repulsive energy emanating from space (“dark energy”), as during the inflationary period shortly after the Big Bang.
.
At this time, it is open to question whether such acceleration will permanently keep augmenting with the increase of space in the universe or whether there could be a reduction in repulsive energy and, ultimately, a reversal, leading to a new collapse of the universe.
.
The other remaining mystery of the universe is given by the fact that only a small amount of all the mass or matter constituting the universe is visible or detectable. The vast balance of all matter is called “dark matter” but has not yet been identified or fully located.
.
In sum, the content of the universe is now seen by some scientists as being only 5% in conventional matter (atoms, molecules), 25% (or more) in “dark matter, and possibly 70% in the still mysterious “dark energy” – unless substantial corrections come from the recently discovered larger weight of the numerous “brown dwarfs” and smaller stars. This indicates the magnitude of the challenge for science in trying to fully understand the universe – in addition to the question of unifying relativity theory based on gravity with quantum mechanics concerning the world of subatomic particles, electrons, and atoms.
.
.
2.
The Origin and
Evolution
of Earth,
the Moon, and the Atmosphere
.
2.1 The origin of our “Earth”
.
The band where our Earth was formed around the Sun contained much iron and other heavy materials as well. Most importantly, this band also contained enough carbon, oxygen, nitrogen, phosphorus, sulfur, calcium, silicon, and water that were so very important for its future development. This mix should not be considered overly exotic. The universe is old enough for many super-star collapses and supernovae to have occurred in our and many other galaxies, thereby seeding the space within the “arms” of their respective galaxies and in between the arms with all those heavy elements, as indicated earlier.
.
The specific composition and rate of rotation of the cloud of dust where our solar system was formed was favorable for the later development of life. Our resulting Sun had a size to allow a long period of sufficient energy production. A smaller size would have provided less energy, a larger size a shorter solar life. The rate of rotation allowed heavy planet formation at a suitable distance from the Sun, with a higher rate of rotation of the disk having resulted in planets at a greater distance with less solar energy availability and a slower rate of rotation having formed no heavy planets or only closer to the Sun with excessive solar radiation.
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The accreting and initially very hot Earth allowed the heaviest materials (iron, nickel, and others) to sink into its center. Some of the captured material was slightly radioactive, for the reasons indicated above, with very long decay times. This caused the inner areas of Earth to continually be heated up, resulting in some inner convulsion, which led to a protective magnet field and, equally important, to plate tectonics, as described later. A balance between this core heating effect and the dissipation of the heat through the Earth’s surface and its atmosphere corresponds to the size of the Earth and its age – and could be typical of such planets in other parts of the universe.