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THE DAILY ASTRONOMER
Monday, September 26, 2022
Egg to Apple - A Guide to Big History III - The Thresholds    Part I:  0 - 4

Big History places eight thresholds throughout natural history, starting
with the Big Bang event and continuing to today's modern revolution. (Some
include a ninth threshold in reference  to the future.  We've included
"threshold zero." )     The eight designated thresholds serve as markers:
time periods  when conditions were conducive to an increase  in
complexity.   For that is truly one focus of Big History:  how complexity
arose in small pockets within a Universe  that otherwise bends toward
entropy, increasing states of disorder.    What transpired to transform
energy and simple gases into  towns, villages and megacities inhabited by
creatures possessed of unfathomably intricate minds.

Today and tomorrow we introduce and provide cursory explanations of each
threshold.  Throughout the course, we'll delve into each threshold in much
greater detail.

We begin before the beginning: with threshold zero.*

*THRESHOLD ZERO:  BEFORE THE BEGINNING*
The frustration one experiences when studying origins is the notion of
first causes.   Whether it be the emergence of Gaia, Tartarus and Eros from
the primordial chaos, the marriage of the Maori Rangi and Papa, whose
couplings precipitated the world's creation, or even the Big Bang Theory,
itself,  each scenario prompts the nagging question:  what preceded that
which drew creation, itself, into existence?    Even though Stephen Hawking
once remarked that asking "what occurred before the Big Bang" was akin to
asking what exists one degree north of the North Pole, many cosmologists
today regard the concept of existence preceding the Big Bang quite
seriously.   This  concept pertains  to the "multiverse," a vast array of
distinct universes arising bubble-like from a space-time foam.*

[image: couldamultiv.jpg]

According to the multiverse theory, the event we regard as the  "Big Bang"
coincided with the emergence of our universe arising out of some unknown
-or, more likely, unknowable-  field.    Each universe is distinctive in
character and governed by its own physical laws.    In only a few, perhaps,
are conditions conducive to life's development.      Ours is one such
Universe. The fundamental physical forces -gravitation, electromagnetism,
the strong and weak nuclear forces- differ in both relative strength and
range.    For instance, even though gravitation is of infinite range, it is
the weakest of them all.   Were it even slightly stronger, the Universe
would have imploded back in on itself soon after its birth.  Had it been
slightly weaker, the matter within the cosmos wouldn't have coalesced  to
form stars and planets, both essential for life.  We're here discussing the
Universe because it permitted us to evolve to this point.    The
fundamental forces were just exactly right: the first "goldilocks
condition."       Millions, if not billions, of alternate Universes might
be fleeting in their duration or utterly lifeless.

Yet, again, however, we are confronted with the mystery of first causes.
If ours is a Universe that arose from such a "foam," from what did that
"foam" arise?  Moreover, what would have produced that which produced the
foam?   One can see that these inquiries could quickly ensnare us in an
infinite regress with no starting point: a column consisting of an
indeterminate number of tortoises.

Threshold Zero serves simply as an acknowledgement of what might have
preceded the genesis event we've dubbed "the Big Bang."  However, much like
the deist God that creates and then abandons, this threshold, if it exists
at all, does so well beyond our bounds, hence the designation of zero.
 The course will focus on all the subsequent thresholds, those which are
knowable to us.

So, we give a passing nod to Threshold Zero and then go on our way.



[image: lbh2.jpg]
*THRESHOLD ONE:   THE BIG BANG*
The very beginning, at least of our Universe.    Current estimates pinpoint
the birth of the cosmos to 13.84 billion years ago.      Although physical
models do not enable us to describe  the precise first moment, cosmologists
have developed a thorough  timeline from the first knowable moment
(0.00000000000000000000000000000000000000001 second after the Big Bang)
throughout the various stages of the Universe's inception.   The Big Bang
and the events immediately subsequent to it define threshold one.

*THRESHOLD TWO:  THE FIRST STARS AND GALAXIES*
Approximately 100 million years elapsed between the Big Bang and the
formation of the first stars, known as *Population III*.     In this
metal-poor infant Universe, this first generation of stars consisted almost
entirely of hydrogen and helium, the two simplest elements.  The clusters
consisting of these stars eventually coalesced to produce vast
amalgamations of stars called galaxies.  Though known colloquially as
"island universes," these galaxies often collided and merged to form larger
aggregates.      Threshold two represents the first time larger, distinct
and independent structures formed out of the vast swaths of material
scattered throughout the Universe.

*THRESHOLD THREE:  CHEMICAL ELEMENTS*
The first stars performed a vital role in our story in that they imparted
heavier elements into their local environments.       Every active star
generates energy through thermonuclear fusion: the process by which lighter
elements are transmuted into heavier elements.  For instance, at this very
moment, the Sun is fusing hydrogen into helium and in the process is
transmuting some of the initial material into energy.    Eventually (about
five billion years from now), the Sun will exhaust its core hydrogen
reserves and will proceed with helium burning: the fusion sequence
resulting in the creation of carbon.

_____________________________________
*ASTRONOMICAL NOTE:*
Astronomers consider all elements heavier than helium to be "metals."
_____________________________________

Although the Sun is not sufficiently massive to produce the pressures and
temperatures necessary to burn carbon, more massive stars can. In fact,
highly massive stars will continue the fusion processes through carbon,
oxygen, silicon, and up to iron.    No star, no matter how massive, can
fuse iron into any heavier elements, for such processes are *endothermic*,
meaning that they consume more energy than they impart back into the star.
   Consequently, the delicate counterbalance between the star's outward
energy pressure and the inward gravitational pull is violently disrupted.
  These stars explode as Type II supernovae.   These supernovae are so
prodigiously energetic they can produce all the naturally occurring
elements heavier than iron.   They also disperse this heavy-metal material
into their surroundings.

The Population III stars served as the first element factories of the
Universe.  They generated many through their thermonuclear processes and
then perished in explosions that both created the heaviest elements and
dispersed the material throughout nearby regions, thereby chemically
enriching them.


*THRESHOLD FOUR: EARTH AND THE SOLAR SYSTEM*
More than five billion years ago, a Population II star exploded as a Type
II supernova.    Some of the expelled material encountered a cool, dark
nebula consisting primarily of hydrogen and helium.   The incorporation of
these supernova remnants into the dormant cloud precipitated a slow but
inexorable collapse which, over a period of more than ten million years,
formed a galactic (or open) star cluster, one member of which was the Sun.
 Yes, that parent star that blazes in our sky  now formed about five
billion years ago, along with hundreds of other stars that have long since
separated from this cluster and now occupy various regions within the
galaxy.

[image: 149890main_BetaPictDiskbMac.jpg]

Around the Sun -and most likely around all those other stars- a disc of
extraneous material took shape.    From this disc the planets, asteroids
and other attendant bodies slowly formed.  The bodies destined to become
the planets incorporated all their surrounding materials into them while in
the process of establishing stable orbits.   While three of these planets
-Venus, Earth and Mars- move within the "habitable zone," a region where
temperatures could be conducive to life's development, only on Earth did
life actually take hold and evolve into an advanced state.

Tomorrow, thresholds  5 - 8:

*THRESHOLD FIVE:  LIFE*

*THRESHOLD SIX:  COLLECTIVE LEARNING*



*THRESHOLD SEVEN:  AGRICULTURE*
*THRESHOLD EIGHT:  THE MODERN REVOLUTION*



*I want to emphasize that this threshold is our own addition and is not
recognized as one of the Big History thresholds as defined by Big History
co-founder  Dr. David Christian.

**This is an instance in which we must describe highly  abstract concepts
in terms with which we are already familiar.    We do not intend to suggest
that space-time can ever assume the consistency of foam.

_____________________________________________________
*EGG TO APPLE:    HELEN*

[image: 1_m-hCwTqWqhBsbpKEl49i4Q.jpeg]
Whatever else might be said of that capricious and at times tyrannical
ruler, one must concede that King Tyndareus ardently loved his four
children.   Or, more correctly, he loved the four children who were hatched
out of the two eggs his wife, Queen Leda, had produced soon after she and
her husband made love by a lake.    Careful readers will recall that just
after their tryst, while Tyndareus was off enjoying a post-coital jaunt
through a nearby forest, Leda was approached and hastily seduced by Zeus,
who had assumed the form of a swan.   When he returned, Tyndareus noticed
his otherwise naked wife coated in feathers and promptly drew the correct
conclusion.  She had had relations with a god who had assumed the form of a
swan.  Apart from reproaching her for this infidelity, Tyndareus treated
her with compassion and sympathy.    He knew that she was as devoted to him
as he was to her.  Moreover, Tyndareus also knew that if, let's say,
Aphrodite or Artemis had attempted to seduce him - while preferably not in
the form of a swan- he would have found it exceedingly difficult to
resist.

Despite Leda''s extramarital liaison and the subsequent arrival of two
eggs, King Tyndareus quickly developed an abiding love for the four
children who emerged from those eggs.  From one egg, Castor and
Clytemnestra; from the other, Pollux  and Helen.   His affection for these
four is all the more remarkable considering that he understandably wondered
about their paternity.  Perhaps the god sired none of them or, as was more
likely considering the level of Olympian potency, all of them.       As
they grew, however, he and Leda suspected that two of the children,
Clytemnestra and Castor, were his.   Both bore a resemblance to the King:
Castor's was striking, whereas Clytemnestra's was more subtle.    The other
two, however, showed no resemblance at all.   In fact, though Clytemnestra
exhibited a beguiling loveliness even as a young girl, Helen's beauty was
unsurpassed .  She not only became the world's most beautiful woman, but
many went so far as to suggest that hers was a "divine beauty."

Helen was no more his daughter than Pollux was his son. Tyndareus loved her
all the same.   Yet, he was troubled.  She captivated all those who beheld
her and, in time, would be able to claim any man in the world as her
husband.   Tyndareus knew, however,  that such beauty could prove quite
dangerous for mortals, even those of semi-divine parentage.  Goddesses,
notorious for their pride, could not abide rivals from the lower order,
especially those whose attributes were widely perceived as being superior
to those of the Olympians.  Concerned primarily about Aphrodite, Tyndareus
instilled in both his daughters a sense of humility and modesty.    "Be
gladdened by your beauty, but do not boast of it,"  he often warned them.
    He also insisted they both pay homage to Aphrodite, in order to
propitiate the often jealous and wrathful goddess.     Much to Tyndaerus'
gratification, Helen was not only humble about her beauty, but quite kind,
though, at times, mischievous. (She loved to play pranks on her siblings,
much to their chagrin.)

Even though King Tyndareus was as protective as he was loving, he was
unable  to shield Helen from all menaces.  When Helen was only twelve years
old, Theseus -yes, the same Theseus who slew the minotaur- and his cousin
Pirithous abducted her and carried her off to the home of Theseus' mother
Aethra.      Theseus' motivation remains uncertain.   Some believe that he
merely wanted Helen as his wife, for he had heard of her beauty and desired
her.   However, it has also been suggested that he heard a prophecy
declaring that Helen's abduction would precipitate the greatest war the
world had ever known.     The glory-seeking Theseus, who was determined
that his name would be as famous as that of his cousin Heracles, might have
hoped that he would start that war and thus his name would remain forever
known.

One might argue that the second of these two possibilities is the more
likely because Theseus did not attempt to ravish or even seduce the young
Helen.  Instead, he simply left her in his mother's care while he and
Pirithous ventured down to the underworld.     You see, these two had an
agreement whereby each would assist the other in the abduction of a
female.   Pirithous helped Theseus to kidnap Helen and then Theseus
foolishly agreed to help Pirithous to kidnap Persephone, Queen of the
Underworld and wife of Hades.     Well, Hades, being a god, was well aware
of their aim when the two mortals approached his palace.  He welcomed them
warmly into his home and invited them to sit down at his table for dinner.
  As soon as they sat down, however, they both forgot everything: their
names, their personal histories, their quest, everything. The wily Hades
had tricked them into sitting on the chair of forgetfulness where they
would remain in a state of hopeless insensibility forever.*

Meanwhile, Castor and Pollux quickly rescued their sister, for they were
quickly told where she had been taken.      They found Helen and brought
her, and Aethra back to their home.  From that time onward, Aethra would
serve as Helen's waiting woman.    It was fortunate for Theseus that he was
not present when they arrived.  Although he was prodigiously strong and
possessed undaunted courage, he would have been no match for the brothers
Gemini.       It is ironic that Theseus lived only because he was trapped
in the land of the dead when Castor and Pollux saved their sister Helen.

After the remaining few years of her childhood -during which time she was
kept under close watch- it came time for Helen to marry.    Every single
-and already married- man throughout the Hellenistic world and beyond laid
siege to Tyndareus' palace in the hope of becoming Helen's husband.   Soon
the beleaguered king found himself surrounded by a bustling throng of
desperate suitors.    He was terribly worried, for he knew that by choosing
one suitor, he would enrage all the others.    They were all inconveniently
virile, strong and well armed men, all of whom considered themselves the
most appropriate choice.   In other words, men who might not accept
disappointment philosophically.     Fortunately, one of the men present, a
man named *Odysseus* (yes, please remember that name), approached him with
a solution.    "Prior to selecting Helen's future husband," Odysseus
suggested,  "have each man swear a solemn oath to preserve Helen's marriage
no matter to whom she is wed.  Have them swear to likewise defend the
marriage against anyone who attempts to disrupt it.     Tell them that only
those who take such a vow will be considered."

Tyndareus was both relieved and delighted.   He told all the attendant men
about the mandatory oath and, despite some grumblings, they all dutifully
swore it.    Once this long oath-taking process was completed,  King
Tyndareus announced that Helen would marry the Spartan King Menelaus.
 This king was, indeed, handsome, strong, wealthy and powerful and so
Tyndareus assumed that Helen would fall in love with him in time.      The
other men were predictably chagrined to have been excluded but, having been
oath-bound to preserve and defend the marriage, did not protest and started
to withdraw.

Tyndareus did try to mollify Menelaus' brother Agamemnon by having him wed
Helen's beautiful half-sister Clytemnestra.      He also arranged for
Odysseus to marry Penelope, the comely daughter of his brother Icarius.**
Truth be told Odysseus never wanted to marry Helen, or, at least, never
expected  to be seriously considered.   Besides, he had already fallen in
love with Penelope and hoped that King Tyndareus would reward him for his
helpful suggestion by arranging a marriage with the king's niece, which, of
course, he  did.

So, Helen married Menelaus.    Clytemnestra married Agamemnon and Penelope
married Odysseus.    And they all lived happily.....for a while.


*Heracles rescued Theseus when he traveled to the underworld to complete
his twelfth and last labor, the capture of Cerberus.   Or, more accurately,
Hades allowed Heracles to pull Theseus off the chair.  In so doing, much of
the flesh of Theseus' backside remained attached to the chair, which is why
Theseus was often known as the fellow with the small posterior.   Hades
would not let Heracles remove Pirithous, however, for Hades knew that he
was the one who had instigated the attempted abduction of his beloved
Persephone.    Pirithous remains there to this day, in a state of complete
forgetfulness.

**Not to be confused  with Icarus, the son of Daedalus who flew upon waxen
wings and ventured too close to the Sun.
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