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Sunday, October 25, 2015
Reading List: Concrete Planet
- Courland, Robert.
Amherst, NY: Prometheus Books, 2011.
Visitors to Rome are often stunned when they see the
learn it was built almost 19 centuries ago, during the reign
of the emperor Hadrian. From the front, the building has a
classical style echoed in neo-classical government buildings
around the world, but as visitors walk inside, it is the amazing
dome which causes them to gasp. At 43.3 metres in diameter, it was the
largest dome ever built in its time, and no larger dome has, in all the centuries
since, ever been built in the same way. The dome of the Pantheon is a monolithic
structure of concrete, whose beauty and antiquity attests to the
versatility and durability of this building material which has become
a ubiquitous part of the modern world.
To the ancients, who built from mud, stone, and later brick, it must have
seemed like a miracle to discover a material which, mixed with water, could
be moulded into any form and would harden into stone. Nobody knows how or where
it was discovered that by heating natural limestone to a high temperature it
could be transformed into
quicklime (calcium oxide),
a corrosive substance which reacts exothermically with water, solidifying into
a hard substance. The author speculates that the transformation of limestone
into quicklime due to lightning strikes may have been discovered in Turkey and
applied to production of quicklime by a kilning process, but the evidence for this
is sketchy. But from the neolithic period, humans discovered how to make
floors from quicklime and a binder, and this technology remained in use until
the 19th century.
All of these early lime-based mortars could not set underwater and were
vulnerable to attack by caustic chemicals. It was the Romans who discovered
that by mixing volcanic ash
(pozzolan), which was
available to them in abundance from the vicinity of Mt. Vesuvius, it was possible
to create a “hydraulic cement” which could set underwater and
was resistant to attack from the elements. In addition to structures like the
Pantheon, the Colosseum, roads, and viaducts, Roman concrete was used to build
the artificial harbour at
Caesarea in Judea,
the largest application of hydraulic concrete before the 20th century.
Jane Jacobs has
written that the central aspect of a dark age is not that specific things
have been forgotten, but that a society has forgotten what it has
forgotten. It is indicative of the dark age which followed the fall of
the Roman empire that even with the works of the Roman engineers remaining
for all to see, the technology of Roman concrete used to build
them, hardly a secret, was largely forgotten until the 18th century, when a few
buildings were constructed from similar formulations.
It wasn't until the middle of the 19th century that the precursors of modern
cement and concrete construction emerged. The adoption of this technology
might have been much more straightforward had it not been the case that a
central player in it was
William Aspdin, a
world-class scoundrel whose own crookedness repeatedly torpedoed ventures
in which he was involved which, had he simply been honest and straightforward
in his dealings, would have made him a fortune beyond the dreams of avarice.
Even with the rediscovery of waterproof concrete, its adoption was slow in
the 19th century. The building of the
Thames Tunnel by
the great engineers
Marc Brunel and his son
Isambard Kingdom Brunel
was a milestone in the use of concrete, albeit one achieved only after
a long series of setbacks and mishaps over a period of 18 years.
Ever since antiquity, and despite numerous formulations, concrete had one
common structural property: it was very strong in compression (it resisted
forces which tried to crush it), but had relatively little tensile
strength (if you tried to pull it apart, it would easily fracture). This
meant that concrete structures had to be carefully designed so that the
concrete was always kept in compression, which made it difficult to build
cantilevered structures or others requiring tensile strength, such as many
bridge designs employing iron or steel. In the latter half of the 19th century,
a number of engineers and builders around the world realised that by
embedding iron or steel reinforcement within concrete, its
tensile strength could be greatly increased. The advent of
concrete allowed structures impossible to build with pure concrete. In
1903, the 16-story
in Cincinnati became the first reinforced concrete skyscraper, and the
tallest building today, the
Burj Khalifa in
Dubai, is built from reinforced concrete.
The ability to create structures with the solidity of stone, the strength
of steel, in almost any shape a designer can imagine, and at low cost
inspired many in the 20th century and beyond, with varying degrees of
success. Thomas Edison saw in concrete a way to provide affordable houses
to the masses, complete with concrete furniture. It was one of his less
successful ventures. Frank Lloyd Wright quickly grasped the potential
of reinforced concrete, and used it in many of his iconic buildings. The
Panama Canal made extensive use of reinforced concrete, and the Hoover Dam
demonstrated that there was essentially no limit to the size of a structure
which could be built of it (the concrete of the dam is still curing to
this day). The Sydney Opera House illustrated (albeit after large schedule
slips, cost overruns, and acrimony between the architect and customer) that
just about anything an architect can imagine could be built of reinforced
To see the Pantheon or Colosseum is to think “concrete is eternal”
(although the Colosseum is not in its original condition, this is mostly
due to its having been mined for building materials over the
centuries). But those structures were built with unreinforced Roman
concrete. Just how long can we expect our current structures, built from
a different kind of concrete and steel reinforcing bars to last?
Well, that's…interesting. Steel is mostly composed of iron, and iron
is highly reactive in the presence of water and oxygen: it rusts. You'll
observe that water and oxygen are abundant on Earth, so unprotected steel
can be expected to eventually crumble into rust, losing its structural
strength. This is why steel bridges, for example, must be regularly
stripped and repainted to provide a barrier which protects the steel
against the elements. In reinforced concrete, it is the concrete itself
which protects the steel reinforcement, initially by providing an alkali
environment which inhibits rust and then, after the concrete cures, by
physically excluding water and the atmosphere from the reinforcement. But,
as builders say, “If it ain't cracked, it ain't concrete.”
Inevitably, cracks will allow air and water to reach the reinforcement,
which will begin to rust. As it rusts, it loses its structural strength
and, in addition, expands, which further cracks the concrete and allows
more air and moisture to enter. Eventually you'll see the kind of
crumbling used to illustrate deteriorating bridges and other infrastructure.
How long will reinforced concrete last? That depends upon the details. Port
and harbour facilities in contact with salt water have failed in less than
fifty years. Structures in less hostile environments are estimated to have a life
of between 100 and 200 years. Now, this may seem like a long time compared
to the budget cycle of the construction industry, but eternity it ain't, and
when you consider the cost of demolition and replacement of structures such as
dams and skyscrapers, it's something to think about. But obviously, if the
Romans could build concrete structures which have lasted millennia, so can we.
The author discusses alternative formulations of concrete and different kinds
of reinforcing which may dramatically increase the life of reinforced concrete
This is an interesting and informative book, but I found the author's style
a bit off-putting. In the absence of fact, which is usually the case when
discussing antiquity, the author simply speculates. Speculation is always
clearly identified, but rather than telling a story about a shaman discovering
where lightning struck limestone and spinning it unto a legend about the
discovery of manufacture of quicklime, it might be better to say, “nobody
really knows how it happened”. Eleven pages are spent discussing the
thoroughly discredited theory that the Egyptian pyramids were made of concrete,
coming to the conclusion that the theory is bogus. So why mention it?
There are a number of typographical errors and a few factual errors (no, the
Mesoamericans did not build pyramids “a few of which would equal those
Still, if you're interested in the origin of the material which surrounds us
in the modern world, how it was developed by the ancients, largely forgotten,
and then recently rediscovered and used to revolutionise construction, this is
a worthwhile read.
Monday, October 19, 2015
Reading List: The Road to Relativity
- Einstein, Albert, Hanock Gutfreund, and Jürgen Renn.
The Road to Relativity.
Princeton: Princeton University Press, 2015.
One hundred years ago, in 1915, Albert Einstein published the final
version of his general theory of relativity, which extended his 1905
special theory to encompass accelerated motion and gravitation. It
replaced the Newtonian concept of a “gravitational force”
acting instantaneously at a distance through an unspecified mechanism
with the most elegant of concepts: particles not under the influence
of an external force move along spacetime
generalisation of straight lines, but the presence of mass-energy
curves spacetime, which causes those geodesics to depart from straight
lines when observed at a large scale.
For example, in Newton's conception of gravity, the Earth orbits the Sun
because the Sun exerts a gravitational force upon the Earth which pulls it
inward and causes its motion to depart from a straight line. (The Earth also
exerts a gravitational force upon the Sun, but because the Sun is so much
more massive, this can be neglected to a first approximation.) In general
relativity there is no gravitational force. The Earth is moving in a straight
line in spacetime, but because the Sun curves spacetime in its vicinity this
geodesic traces out a helix in spacetime which we perceive as the Earth's
Now, if this were a purely qualitative description, one could dismiss it
as philosophical babble, but Einstein's theory provided a precise description
of the gravitational field and the motion of objects within it and, when
the field strength is strong or objects are moving very rapidly, makes
different predictions than Newton's theory. In particular, Einstein's theory
predicted that the perihelion of the orbit of Mercury would rotate around the
Sun more rapidly than Newton's theory could account for, that light propagating
near the limb of the Sun or other massive bodies would be bent through twice the
angle Newton's theory predicted, and that light from the Sun or other
massive stars would be red-shifted when observed from a distance. In due
course all of these tests have been found to agree with the predictions of
general relativity. The theory has since been put to many more precise
tests and no discrepancy with experiment has been found.
For a theory which is, once you get past the cumbersome
mathematical notation in which it is expressed, simple and elegant, its
implications are profound and still being explored a century later.
cosmology and the large-scale
structure of the universe,
and gravitational radiation
are all implicit in Einstein's equations, and exploring them are among
the frontiers of science a century hence.
Unlike Einstein's original 1905
paper on special
relativity, the 1915 paper, titled
“Die Grundlage der allgemeinen
Relativitätstheorie” (“The Foundation of General
Relativity”) is famously difficult to comprehend and baffled many
contemporary physicists when it was published. Almost half is a tutorial
for physicists in
multidimensional geometry and the
in which it is expressed. The balance of the paper is written in this
notation, which can be forbidding until one becomes comfortable with
That said, general relativity can be understood intuitively the same way
Einstein began to think about it: through thought experiments. First,
imagine a person in a stationary elevator in the Earth's gravitational
field. If the elevator cable were cut, while the elevator was in free
fall (and before the sudden stop), no experiment done within the elevator
could distinguish between the state of free fall within Earth's gravity
and being in deep space free of gravitational fields. (Conversely, no
experiment done in a sufficiently small closed laboratory can distinguish
it being in Earth's gravitational field from being in deep space accelerating
under the influence of a rocket with the same acceleration as Earth's gravity.)
(The “sufficiently small” qualifier is to eliminate the effects
of tides, which we can neglect at this level.)
The second thought experiment is a bit more subtle. Imagine an observer
at the centre of a stationary circular disc. If the observer uses rigid
rods to measure the radius and circumference of the disc, he will find
the circumference divided by the radius to be 2π, as expected from
the Euclidean geometry of a plane. Now set the disc rotating and repeat
the experiment. When the observer measures the radius, it will be as
before, but at the circumference the measuring rod will be contracted
due to its motion according to special relativity, and the circumference,
measured by the rigid rod, will be seen to be larger. Now, when the circumference
is divided by the radius, a ratio greater than 2π will be found, indicating
that the space being measured is no longer Euclidean: it is curved. But
the only difference between a stationary disc and one which is rotating is
that the latter is in acceleration, and from the reasoning of the first
thought experiment there is no difference between acceleration and gravity.
Hence, gravity must bend spacetime and affect the paths of objects (geodesics)
Now, it's one thing to have these kinds of insights, and quite another to
puzzle out the details and make all of the mathematics work, and this
process occupied Einstein for the decade between 1905 and 1915, with many
blind alleys. He eventually came to understand that it was necessary to
entirely discard the notion of any fixed space and time, and express the
equations of physics in a way which was completely independent of any
co-ordinate system. Only this permitted the metric structure of
spacetime to be completely determined by the mass and energy within it.
This book contains a facsimile reproduction of Einstein's original
manuscript, now in the collection of the Hebrew University of Jerusalem.
The manuscript is in Einstein's handwriting which, if you read German,
you'll have no difficulty reading. Einstein made many edits to the
manuscript before submitting it for publication, and you can see them all
here. Some of the hand-drawn figures in the manuscript have been cut
out by the publisher to be sent to an illustrator for preparation of
figures for the journal publication. Parallel to the manuscript, the
editors describe the content and the historical evolution of the concepts
discussed therein. There is a 36 page introduction which describes the
background of the theory and Einstein's quest to discover it and the
history of the manuscript. An afterword provides an overview of
general relativity after Einstein and brief biographies of principal
figures involved in the development and elaboration of the theory.
The book concludes with a complete English translation of Einstein's
two papers given in the manuscript.
This is not the book to read if you're interested in learning general
relativity; over the last century there have been great advances in
mathematical notation and pedagogy, and a modern text is the best
resource. But, in this centennial year, this book allows you to
go back to the source and understand the theory as Einstein presented it,
after struggling for so many years to comprehend it. The supplemental
material explains the structure of the paper, the essentials of the
theory, and how Einstein came to develop it.
Tuesday, October 13, 2015
Reading List: Sweeter than Wine
- Smith, L. Neil.
Sweeter than Wine.
Rockville, MD: Phoenix Pick, 2011.
A couple of weeks after D-Day, Second Lieutenant J Gifford found
himself separated from his unit and alone in a small French village which,
minutes later, was overrun by Germans. Not wishing to spend the rest of the
war as a POW, he took refuge in an abandoned house, hiding out
in the wine cellar to escape capture until the Allies took the village. There,
in the dark, dank cellar, he encounters Surica, a young woman also hiding from the
Germans—and the most attractive woman he has ever seen. Nature
takes its course, repeatedly.
By the time the Germans are driven out by the Allied advance, Gifford
has begun to notice changes in himself. He can see in the dark. His
hearing is preternaturally sensitive. His canine teeth are growing.
He cannot tolerate sunlight. And he has a thirst for blood.
By the second decade of the twenty-first century, Gifford has established
himself as a private investigator in the town of New Prospect, Colorado,
near Denver. He is talented in his profession, considered rigorously
ethical, and has a good working relationship with the local police. Apart
from the whole business about not going out in daytime without extensive
precautions, being a vampire has its advantages in the gumshoe game: he
never falls ill, recovers quickly even from severe injuries, doesn't age,
has extraordinary vision and hearing, and has a Jedi-like power of suggestion
over the minds of people which extends to causing them to selectively forget
But how can a vampire, who requires human blood to survive, be ethical?
That is the conundrum Gifford has had to face ever since that day in the
wine cellar in France and, given the prospect of immortality, will have to
cope with for all eternity. As the novel develops, we learn how he has
met this challenge.
Meanwhile, Gifford's friends and business associates, some of whom
know or suspect his nature, have been receiving queries which seem to
indicate someone is on to him and trying to dig up evidence against
him. At the same time, a series of vicious murders, all seemingly
unrelated except for their victims having all been drained of blood, are
being committed, starting in Charleston, South Carolina and proceeding
westward across the U.S.
These threads converge into a tense conflict pitting Gifford's ethics
against the amoral ferocity of an Old One (and you will learn just how
Old in chapter 26, in one of the scariest lines I've encountered in
any vampire tale).
I'm not usually much interested in vampire or zombie stories because they
are just so implausible, except as a metaphor for something else. Here,
however, the author develops a believable explanation of the vampire phenomenon
which invokes nothing supernatural. Sure, there aren't really
vampires, but if there were this is probably how it would work. As
with all of the author's fiction, there are many funny passages and turns of
phrase. For a novel about a vampire detective and a serial killer, the
tone is light and the characters engaging, with a romance interwoven with
the mystery and action. L. Neil Smith wrote this book in one month: November, 2009,
as part of the
National Novel Writing Month, but other than
being relatively short (150 pages), there's nothing about it which
seems rushed; the plotting is intricate, the characters well-developed,
and detail is abundant.
Thursday, October 8, 2015
Reading List: SJWs Always Lie
- Day, Vox [Theodore Beale].
SJWs Always Lie.
Kouvola, Finland: Castalia House, 2015.
is the nom de plume and now
nom de guerre of Theodore Beale, a
musician with three Billboard Top 40 credits, video game designer,
author of science fiction and fantasy and three-time Hugo Award
nominee, and non-fiction author and editor.
If you're not involved in the subcultures of computer gaming or
science fiction and fantasy, you may not be acquainted with terms
such as SJW (Social Justice Warrior),
or Sad Puppies.
You may conclude that such matters are arcana relating to subcultures
of not-particularly-socially-adept people which have little bearing
on the larger culture. In this, you would be wrong. For almost fifty
years, collectivists and authoritarians have been infiltrating
cultural institutions, and now occupy the high ground in institutions
such as education, the administrative state, media, and large
corporations. This is the “long march through the institutions”
and it has, so far, been an extraordinary success, not only advancing
its own agenda with a slow, inexorable ratchet, but intimidating opponents
into silence for fear of having their careers or reputations destroyed.
Nobody is immune: two Nobel Prize winners,
have been declared anathema because of remarks deemed offensive by
SJWs. Nominally conservative publications such as
National Review, headquartered in hives of collectivist
corruption such as New York and Washington, were intimidated into a
reflexive cringe at the slightest sign of outrage by SJWs, jettisoning
superb writers such as
and John Derbyshire in
an attempt to appease the unappeasable.
Then, just as the SJWs were feeling triumphant, GamerGate came along,
and the first serious push-back began. Few expected the gamer
community to become a hotbed of resistance, since gamers are all
over the map in their political views (if they have any at all), and are
a diverse bunch, although a majority are younger males. But they have a
strong sense of right and wrong, and are accustomed to immediate and
decisive negative feedback when they choose unwisely in the games
they play. What they came to perceive was that the journalists
writing about games were applauding objectively terrible
games, such as
due to bias and collusion among the gaming media.
Much the same had been going on in the world of science fiction.
SJWs had infiltrated the
Fiction and Fantasy Writers of America
to such an extent that they directed their Nebula Awards to
others of their ilk, and awarded them based upon “diversity”
rather than merit. The same rot had corrupted fandom and its Hugo
Vox Day was near the centre of the cyclone in the revolt against all
of this. The campaign to advance a slate of science fiction
worthy of the Hugos rather than the pap selected by the SJWs resulted
in the 2015 Hugos being blown up, demonstrating that SJWs would
rather destroy a venerable institution than cede territory.
This book is a superbly written history of GamerGate and the revolt
against SJWs in science fiction and fantasy writers' associations
and fandom, but also provides deep insight into the seriously
dysfunctional world of the SJW and advice about how to deal with
them and what to do if you find yourself a target. The tactics of
the SJWs are laid bare, and practical advice is given as to how to
identify SJWs before they enter your organisation and how to get
rid of them if they're already hired. (And get rid of them you
must; they're like communists in the 1930s–1950s: once in place
they will hire others and promote their kind within the organisation.
You have to do your homework, and the Internet is your friend—the
most innocuous co-worker or prospective employee may have a long
digital trail you can find quickly with a search engine.)
There is no compromising with these people. That has been the key
mistake of those who have found themselves targeted by SJWs. Any
apology will be immediately trumpeted as an admission of
culpability, and nothing less than the complete destruction of
the career and life of the target will suffice. They are not
well-meaning adversaries; they are
you must, if they attack you, seek to destroy them just as they
seek to destroy you.
they have. I'm not suggesting you call in SWAT raids on their
residences, dig up and release damaging personal information
on them, or make anonymous bomb threats when they gather. But be
aware that they have used these tactics repeatedly against their
You must also learn that SJWs have no concern for objective facts.
You can neither persuade nor dissuade them from advancing their
arguments by citing facts that falsify their claims. They will
repeat their objectively false talking points until they tire you
out or drown out your voice. You are engaging in
they are employing
rhetoric. To defeat
them, you must counter their rhetoric with your own rhetoric, even
when the facts are on your side.
Vox Day was in the middle of these early battles of the counter-revolution,
both in GamerGate and the science fiction insurrection, and he
provides a wealth of practical advice for those either attacked by
SJWs or actively fighting back. This is a battle, and somebody is
going to win and somebody else will lose. As he notes, “There can
be no reconciliation between the observant and the delusional.” But
those who perceive reality as it is, not as interpreted through a
“narrative” in which they have been indoctrinated, have
an advantage in this struggle. It may seem odd to find gamers and
science fiction fans in the vanguard of the assault against this
insanity but, as the author notes, “Gamers conquer Dragons and
fight Gods for a hobby.”
Friday, October 2, 2015
Mac OS: Scaling El Capitan
Other than installing routine security patches, I haven't bothered to update the operating system of “Ansel”, the Macintosh Pro I installed in 2009 primarily to do photographic and video production. The applications I use were primarily developed for that platform, and while I prefer to avoid proprietary software, it's a much better choice than anything tainted by Microsoft.
I was finally pushed to bring the system up to date due to nagging by Apple that upgrading my iPhone and iPad to iOS 9 might cause problems synchronising with the old version of iTunes on my desktop system. (I haven't investigated the details of this, but no newer version of that regrettable application is available for the old operating system I was running.) I decided to jump all the way to the newest release, “El Capitan
”, posted as an official release on 2015-09-30.
I downloaded the update and started the installer, after making sure
I had a complete Time Machine backup of the existing system. The
installer ran for about a minute and then said it was restarting
to perform the installation. It went into a shutdown process and
hung with two blue screens and nothing but the cursor on the screen.
After about 15 minutes in this state, I discovered I could log into
the system with SSH, and that it was still running the old system
with an uptime indicating no reboot had happened. I did a
after which my SSH window disconnected and the cursor on the blue
screen was replaced by a spinning disc icon.
This persisted for more than half an hour, during which time the system
would respond to pings but not an SSH connection. Finally, it
spontaneously restarted into an installer screen which said it had
about half an hour to go.
After around 45 minutes, it rebooted again and came up into what
looked like an initial setup screen, warning me that two applications
were not compatible with the new system. As I was about to look around
the new system it crashed, rebooted, and came up with the "problem" screen
and then the desktop.
Just about everything I tried would bounce me out after a few
seconds to what looked like a login screen, which would require
me to enter the password for a few seconds more access, after which
it would bounce again. I made sure screen lock and screen saver
were off and even removed my login password: nothing doing.
I was also getting weird tearing on the screen, failure to
refresh windows when uncovered, and a frozen cursor, after which
the inevitable pop.
The network settings were lost in the “upgrade”. I re-established
the WiFi connection to Fourmilab with settings as follows:
Search: lan.fourmilab.ch dmz.fourmilab.ch fourmilab.ch
The “upgrade” disabled SSH logins. I went into System Settings/Sharing and
set “Enable remote logins” between pops to the login screen.
Now I was able to SSH login from Hayek and access the system in text
mode without pops.
Tried iTunes. Of course, it doesn't see the Apple TV. I restarted
the Apple TV—nothing doing.
A wired sync of the iPhone to iTunes seems to work. I did not dare
to try installing the iOS 9.0.1 “upgrade” it's been bugging me about.
I unplugged the Time Machine backup disc. If this ends up as badly
as it looks right now, I'll want that as a clean backup to start
over on a new machine.
Based on a discussion of the login crashes, I backed up and deleted
the following in /Library/Preferences
-rw-r--r-- 1 root wheel 229 Oct 1 21:18 com.apple.loginwindow.plist
-rw-r--r-- 1 root admin 2084 Jan 26 2010 com.apple.loginitems.plist
-rw-r--r-- 1 root admin 787 Jan 26 2010 loginwindow.plist
No improvement. It still pops.
Further research on login crashes discovered mentions of display
switching on various video boards, so I unplugged the right monitor.
The pops appear to have gone away, at least for the moment.
I went to the Mac App store and dowloaded 395 Mb of updates, including
good old iTunes. Now I appear to be able to run iTunes without
popping. It shows the Apple TV in the Preferences panel and says
that it's “Syncing” but I cannot find any sync progress indicator
anywhere so I have no idea what it's doing. A
/usr/sbin/tcpdump -l -nn -x -i en2 host 10.1.2.255
doesn't see any traffic going to the Apple TV so I'm not sure I
believe it. All I see is the Apple TV sending multicast broadcast
“Hello. I'm here! Anybody out there?” messages.
Naturally, the new installation of iTunes created its own library
file in “/home/[me]/Music/iTunes/iTunes Media
” and did not
respect the library I was previously using in
”. When I set the
library location to there, it still didn't see the files, since it
continued to use a new “iTunes Library.itl
” file which it had
created containing only content in the “cloud”. I had to restore
the backed-up previous library:
“/Users/[me]/Music/iTunes/Previous iTunes Libraries/iTunes Library 2015-10-01.itl”
“/Volumes/Vault/[me]/Music/iTunes/iTunes Media/iTunes Library.itl”
then start iTunes while holding down the Option key so I could navigate
to that directory where it could then find the .itl file. Now it appears
to see the local content.
With iTunes repaired, I was now able to wipe the computer association of
the Apple TV (because it couldn't possibly remember something like that
across an event as momentous as an operating system upgrade) and start
the re-sync which, if experience is any guide, will run for more than a
In order to get public key logins via SSH to work, I had to:
cp -p authorized_keys2 authorized_keys
on Ansel. “authorized_keys2
” no longer works.
At the moment the machine is running with one of the two monitors I paid for unplugged, dark, and useless, but at least I can use the machine without bizarre abstract art on the screen or popping back to the login screen every minute or so. I'm sure I will discover plenty more as I try to do actual productive work with this machine. I'll add the details to this post.