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Comment Re:Fluid dynamics (Score 1) 63

Traffic is horribly non linear.

So is fluid dynamics.

It's also very complicated and counter-intuitive, to the point that even experts had to resort to models in wind tunnels and scaling laws, until supercomputers and their algorithms could model it down to submicroscopic levels and handle the details of the positive-feedback transitions.

Comment Fluid dynamics (Score 1) 63

By leaving room between their car and the one ahead of them, drivers can absorb a wave of braking in dense traffic conditions that would otherwise be amplified into a full-blown "phantom" traffic jam with no obvious cause. "Just keeping away," he says, can help traffic flow smoothly.

Some driving techniques make traffic behave like fluids: Compressible gasses (Car ahead of you slows - you slow some but progressively more as you get closer, Car beside you jogs left two feet, you jog one foot. etc.) Liquids (cars close up and hold constant distance) Crystals (at a traffic light or full stop, cars close up into a tight ordered array.) Condensation (similar near-constant spacing but not so ordered and flows (more easily), Chrystallization, Melting, Sublimation, Evaporation (when the obstruction clears and the first cars can speed up, then later ones, ...), laminar (smooth) flow, turbulent flow, shock waves, ...

Spacing out lets you behave more like a gas - or the first of the liquid behind a bubble - rather than a liquid or solid. When a sudden speed reduction throws a shock wave at you at several times the traffic speed, you can let the gas compress or the cavitation bubble shrink, diffusing the shock wave into an acoustic wave and avoding a collision with the car ahead. It also lets you even out the flow, remaining laminar rather than starting an eddy and going turbulent.

Comment Re:Cooperative vs competitive (Score 1) 63

Maybe some of these strategies can be expressed as situational behaviors for driving that are ... indicated as desirable by easily observable local conditions ...

If that works out, then we can look into what additional driving tactics could be enabled by an infrastructure that brings in information that is NOT available by local observation, presenting it to the driver in a way that does not cause more problems by distraction that it solves. That would let drivers get some of the advantages of self-driving car network communication, too.

Comment Re:Cooperative vs competitive (Score 1) 63

Maybe self-driving cars can be trained to be cooperative, which would probably result in better driving.

Maybe some of these strategies can be expressed as situational behaviors for driving that are simple enough to be easily understood, indicated as desirable by easily observable local conditons, work when only some people use them, and can be shown to be good for success of the person using them.

Then we could just teach them and gain some of the benefits via voluntary actions driven by enlightened self-interest.

(Sort of like teaching Objectivism to prison inmates - practically the only thing, short of certain real religious conversions - that reduces recidivism, by giving him a recipe for going straight and showing what's in it for the convict if he uses it after release..)

Comment Re:Perhaps galaxies are just ... (Score 1) 25

... this suggests any galaxy (with a central black hole will also have a few hypervelocity stars flying around ... spiral arm or star /star cluster /cloud formation ...

And if so, this should have been going on since galaxies with central black holes were a thing - which is quite early. What might this mean for more recent inter- and galactic architecture?

Comment Perhaps galaxies are just ... (Score 1) 25

Perhaps galaxies are just the accretion disks of big black holes.

(In any case, this suggests any galaxy (with a central black hole will also have a few hypervelocity stars flying around in elliptical orbits from near the center to somewhere much farther out, or on hyperbolas off to bombard the neighborhood.

Nasty traffic problem.

I wonder if this is related to spiral arm or star /star cluster /cloud formation, creates some (currently mysterious) stellar event when one hits another star, or grows the star into a new thingie or big black hole as it scresms through the local background gas and dust and collects a lot of it.

Comment Happy jet-lag day! (Score 1) 197

Just think: You don't even have to take a jet to suffer from jet-lag today! What a money saving! B-b

The twice-annual time change also sickens and kills people. Auto accidents from the spring-forward transition, for instance, kill over 30 people, on the average, per year (and the fall-back transition doesn't provide a compensating life-saving event). Heart attacks spike at the spring transition then remain elevated for weeks. Also bumping up: strokes, workplace injuries, suicides.

As far as I'm concerned the right thing to do is permanent standard time.

  - No time changes. (Save tens to hundreds of lives per year in the US and improve health.)

  - If some (group of) people want their business / government / school hours to be an hour earlier year-round, let them open and close an hour earlier. Similarly if they want to open earlier in the summer if they're far enough fom the equator for it to matter. Offsetting the clocks from "Noon is annual mean solar noon at the middle longitudes of the time zone" is both arbitrary and silly.

Comment Re:In a word... (Score 1) 197

Daylight savings time is a anachronism from agrarian cultural history.

From INDUSTRIAL cultural history.

Though originally proposed by Ben Franklin, what got it going was an attempt to save power when lighting was the bulk of the electrical load. Regardless of how well it worked at the time, once air conditioning became common it ended up being counter-productive: People coming home earlier turned on their ACs at a hotter part of the day, and ended up using more power than decreased lighting saved.

Farmers, on the other hand, hate it: The animals and plants are on a solar schedule that the farmers have to follow for efficient production, but the time-change glitches when they can do off-farm business.

No more than the following "traditions" will be ended, eliminated...

Electoral college.

The electoral college serves (at least) two purposes:

  - The original intent: Keeping one or a handful of big urban states from completely dominating the presidential election. This was part of a deal to make the small states willing to join (and remain), making the federation a large enough military power to defend itself from reconquest and win in other international conflicts and negotiations.

It serves as a firewall to make it hard for one, or a handful, of politically corrupt states from swinging the presidential election away from the actual will of the people. With direct election, in an even moderately close race, a large machine-run state could fraudulently flip/generate/"lose" enough votes to swing it, while with the electoral college they're limited to their state's electors - which they probably had anyway. Also: In a close race with the you only need to recount blatantly suspect states' voters in close-enough-to-fix states, while with popular presidential election you have to recount pretty much the whole country.

Comment Biz reaction to antisemitism in "top schools" (Score 1) 112

Some of this is big businesses' reaction to the antisemitic disruptions in the so-called "top schools". A number of companies have decided to no longer hire the graduates of many of the ivy league schools which have condoned or even supported the anti-jewish intimidation and violence of the allegedly pro-palestinian protests.

Comment The armed forces have been affected for a while. (Score 1) 44

Every party switch will require purging the internal enemies installed by previous regimes and neutrality won't save anyone.

Eventually the armed forces will be affected which is a great way to turn into (r)ussia, but enlisted careers will be safer than officers.

The armed forces have been affected at least since the officer candidate schools began asking whether the student would obey orders to disarm the US citizen civilians in an area. (If I recall correctly this was during the Obama administration.)

Comment Expand article logo Continue reading (Score 2) 19

I know the article snippets get posted pretty much verbatim

But it seems to me that the posting editor ought to read it enough to catch that the submitter's cut-and-paste picked up some inter-paragraph HTML buttons and edit their button-text out of the article posting.

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