
Behind the dead-water phenomenon - chris_overseas
https://phys.org/news/2020-07-dead-water-phenomenon.html
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RcouF1uZ4gsC
> This work is part of a major project investigating why, during the Battle of
> Actium (31 BC), Cleopatra's large ships lost when they faced Octavian's
> weaker vessels. Might the Bay of Actium, which has all the characteristics
> of a fjord, have trapped the Queen of Egypt's fleet in dead water?

The Battle of Actium was one of the great inflection points in history. If
Caesar has lost, the world would have looked a lot different.

One thing I would think that might be against this hypothesis is that
Cleopatra’s flag ship was able to make an escape. It likely would have been
the biggest ship and given that Cleopatra brought a lot of gold with here,
would have been heavily loaded as well.

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ardit33
"If Caesar has lost, the world would have looked a lot different." \--
Octavian, Ceaser was already dead by this point...

And, no, I don't think the world would have looked a lot different as the
system wouldn't have changed... (Mark Antony would have replaced Ocatavian).

As the saying goes, "Rome was not build in one day...." one or two particular
rulers didn't have that much effect on the long term. Rome was build gradually
and expanded through generations of rulers.... If Mark Antony/Cleoptra combo,
was terrible, they would have been eventually been dispatched off, by the
internal forces... just like Nero.

By the time Rome was not facing an outside existential threat (Partha was
tough, but never an existential threat to Rome).

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RcouF1uZ4gsC
> Octavian, Ceaser was already dead by this point...

Only his enemies referred to him as Octavian. He referred to himself as Caesar
as did all his men, and later Romans.

>one or two particular rulers didn't have that much effect on the long term.

Augustus as he became known was probably the single most consequential ruler
in Rome. He was the transition between the upheaval of the Roman Revolution at
the end of the Roman Republic and the Roman Empire.

Without Augustus, it is likely that Rome would have continually been racked by
civil wars. The disaster of the 2nd century where Rome bled itself dry in a
series of civil wars would likely have been moved up. If Antony and Cleopatra
had won, I think what we saw later as the East/West split with the Eastern
capital at Constantinople may have happened much earlier with the Eastern
capital at Alexandria.

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thaumasiotes
> He referred to himself as Caesar as did all his men, and later Romans.

Not just him. Every Roman emperor was called Caesar, which is why Caesar is
the word for emperor in other nearby languages. (Compare Russian czar; German
kaiser.)

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0_____0
I learned recently that Caesar was pronounced like "kai-sar" in the original
Latin, and had thought that it was interesting that it sounded like Kaiser.
You just closed the circle for me on why that is. :)

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foobarbecue
Hunh, interesting. I thought this was going to be similar to vortex ring
state, but seems it's different.

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mleonhard
How can variations in water density put drag on a ship?

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dredmorbius
By creating two or more layers of water which don't mix, and create internal
waves.

A video demo is likely useful.

Here, a (model) boat under a constant force (falling mass to right of screen)
creates an internal wave, eventually slowing the boat until the wave catches
up with the boat, which then accelerates:

[https://invidio.us/watch?v=5bqa3KSZrHQ](https://invidio.us/watch?v=5bqa3KSZrHQ)

Internal waves can create dramatic effects within the water column depending
on bathymetry, whilst leaving. minimal surface evidence:

[https://invidio.us/watch?v=U2lq8TpLqR4](https://invidio.us/watch?v=U2lq8TpLqR4)

Gibraltar is a natural location in wwhich internal waves develop:

[https://invidio.us/watch?v=x7GXLJQ2Zn0](https://invidio.us/watch?v=x7GXLJQ2Zn0)

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thombat
That truly was a case of a picture being worth a thousand words - a much more
dramatic effect than my puny intuition had guessed, and a nice piece of video
editing: a clear view of the salient parts and no blather. Thanks indeed for
posting the links.

