Reasons for AC selection involves sync motors, transformers, and long
range distribution, but I think the strongest reason is the fact that AC
(polarity reversing) does not generate electrolisys at different metal
junctions, so far it avoids chemical alteration and electrical terminals
destruction.

Both AC and DC avoids metal oxydation.  If in use, you can't find a
circuit braker or wire connector with oxydation.  Temperature caused by
bad contact can alter the metal composition, but it is not attacked by
air oxygen in regular use.  It can be oxydated if left unused or
disconnected.

Studies show that nature use only DC charges, even our body generate
DC.  Deep studies show that an atom is in real an AC polarization
generator, that turns to be DC when in use by the charge flow.  The "AC"
characteristics of the atom is what makes it stable and balanced.  This
AC oscillation is caused by the orbital electrons, with harmonics
because electrons spin.  A material could be identified by its atomic AC
characteristics, since its atomic construction is specific, such
electron layers, cycle timmings (frequencies), harmonics and so on.

So the Star Track Mr. Spock's pocket substance identification is not
absurd as many think it is,  Equipments as X-ray fluorescence (XRF) that
can identify more than 225 alloys, or the Atomic Absorbtion
Spectroscopy, or general Spectrometer procedures could be easily
replaced in the future by a simple Radio Frequency Receiver tunned and
searching for known atomic patterns, as well Dr. McCoy personal health
pocket scanner could search for RF patterns that only certain diseases
and body disturbances could generate.  We should always remember that
expensive fiction movies have scientists and astronomers hired to be
fiction consultants. It is somehow easy to identify cheap movies by its
poor and silly fictioned technology.

I don't follow this technology thread for long, but I believe that GHz
communication technology should take in consideration this atomic
interation and frequencies when selecting metals for antenas and
conductors, for a better power flow.

A 48VDC battery can't kill you immediatelly, but if its 5mA current
through a 10kOhms wet human body crosses the heart muscle during certain
time, the muscle will suffer and can go to a fatal arrest.  Safety
speaking, AC is much more recognizable, you can feel microamps of AC,
but not DC.

25 years ago, I was adjusting a 100W radio transmitter final stage on
the bench, somebody just hit the power cord and the transmitter bounced
to fall, my poor instinct made me hold the unit and my hand went
directly over the high voltage power stage tubes plates connectors.
Burn flesh smell all over the place, but almost not pain at all, even
that the palm of my hand got four deep burns to the bones, as if red hot
needles were pushed into it.  I don't recommend that experience to
nobody.  :)  About the transmitter? It went to the floor along with
Wattmeter and oscilloscope...