[image: salmacis.jpg]
*Hermaphroditus:   *Two genders, one body
Honestly, nobody on Olympus or below felt particularly optimistic about the
marriage between Aphrodite, the loveliest goddess, and Hephaestus, the
least lovely god.    Apart from the beauty disparity, their respective
traits were hardly conducive to domestic bliss.   Whereas Aphrodite was
cheerfully sensuous and promiscuous,  Hephaestus was dour, ill-tempered,
and of a jealous disposition.    One must wonder how they could have
possibly have embarked on a relationship in the first place.  Simple. Zeus
arranged the marriage, himself, as he wanted to reward Hephaestus for
having crafted so many implements for his fellow Olympians.   Naturally,
Zeus did not take Aphrodite's opinion into account.    Soon after the
nuptials, Aphrodite began a series of affairs with various mortals and
gods.  As she was the divinely beautiful goddess of love and sexual
attraction, Aphrodite experienced little difficulty in finding eager
paramours.    While most of these trysts were silly little affairs, she
actually fell in love with one of her lovers:  Ares, god of war.   Though
his disposition was hardly more congenial that of Hephaestus, he was far
more handsome and less possessive.     They embarked on a passionate love
affair for quite some time until Hephaestus, who had long suspected his
wife of infidelity, ensnared Ares and Aphrodite in a trap he had set in his
bed.  As the couple lay hopelessly trapped -and naked- Hephaestus came upon
them and invited the Olympians to gather around them.   He was hoping to
avenge this cuckoldry by humiliating Aphrodite and Ares in front of the
others.   Instead, on seeing Aphrodite sans apparel Apollo, Poseidon and
Hermes all developed an intense passion for her.   While Apollo and
Poseidon eventually forgot about their infatuation, Hermes persisted in
it.      Unfortunately for Hermes, the lust was unrequited.   This
rejection caused him to lapse into  such despondency, Zeus felt compelled
to intervene.    While Aphrodite was bathing in the River Achelous, Zeus
deployed an eagle to steal one of her sandals and deliver it to Hermes, who
was then residing in Egypt.   As soon as Helius, the all-seeing Sun god,
told Aphrodite of the sandal's location, she traveled to Egypt and
encountered Hermes.    He offered her the sandal in exchange for carnal
favors.  Such was the sandal's worth she reluctantly complied and in so
doing conceived one son, Hermaphroditus,    Unsurprisingly, he matured
quickly and became a stunningly handsome young man.      Many loved him
ardently, but none so much as the naiad Salmacis.    One day Hermaphroditus
bathed in a pool that Salmacis often frequented.   When she spied him
lounging in the waters, she dove up through the pool and attached herself
to him.   Hermaphroditus struggled to escape her grasp, but to no avail.
 Salmacis then prayed to Poseidon to make them one forever.   He fulfilled
her wish by literally conjoining them into one being possessed of both male
and female parts.     Though powerless to disentangle himself from the
naiad, Hermaphroditus prayed that any man who bathed in the pool would
undergo a similar conversion.    Thus, that remote pool forever more
retained the power to transform men into hermaphrodites.    How many men
underwent this transformation remains unknown.


THE SOUTHWORTH PLANETARIUM
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Julian Date: 24591138.16
2020-2021:  XXXI


THE DAILY ASTRONOMER
Thursday, October 15, 2020
Remote Planetarium 109:  General Relativity V:   Questions


*If matter and energy are the same, can energy affect space-time in the
same way that matter does?  **-L.M.*
Matter is a form of energy,  However, unlike matter, energy lacks any
inertia, or resistance to changes in its motion.    As matter possesses
inertia, it will warp its local space-time regions in ways that energy
cannot.

[image: c2eb859c8c3594afab0610ea94ddd4ae44b4388a.jpg]
A light beam's path is deflected by massive objects.  However, a light beam
will not distort space-time, itself.

*Let's pretend that the Sun vanished from the Universe in an instant.
 Would Earth fall out of its orbit immediately or would it take some time?
-J.S.*
This question pertains to *gravity waves, *a topic we'll be discussing in
greater detail Monday.    The answer is that gravity waves travel at light
speed.  So, for instance, if the Sun vanished from the cosmos
instantaneously, Earth would remain under its gravitational influence for
the next 8.4 minutes, the amount of time light requires to travel between
the Sun and Earth.         Earth would then start to move along a path
tangential to its previous orbit.

*Is it true that in General Relativity, a massive object's gravitational
influence doesn't extend infinitely?   -C.W.*

Yes.  According to GR, a massive object's gravitational influence will not
extend beyond the level of galaxy groups.      On scales smaller than these
groups, spacetime exhibits similar behaviors to Newtonian gravity.    (From
a Newtonian perspective, gravity is of infinite extent.)      However, at
the level of galaxy groups, the galaxies are moving apart as a consequence
of cosmic expansion. Moreover, this expansion rate is increasing due to the
influence of dark energy.   At this level, spacetime wouldn't behave like
Newtonian gravity.

[image: unnamed.jpg]
A massive object's gravitational influence will not extend beyond the level
of galaxy groups according to General Relativity.

*Will I really age faster if I live at the top of a building than in its
basement?*
*-J.W.*
Yes, but the effect will be slight.     A person at the top of a building
will be farther from Earth than a person in its basement.  Consequently,
time will be slower for the observer lower down in the building than higher
up.    However, you won't experience that much more time than the subject
farther down:  nanoseconds per year, only....hardly noticeable.




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