Today I Learned

[strangerep]

They just took everything about Ohm's and inverted them!

...that reminds me of how, as a child, I thought "impedance" was pronounced with emphasis on the "Im". Years later, when I said it aloud in a physics lab, I wondered why the tutor laughed...

 

[Rive]

I read the title as "Word Building", improving vocabulary.

Well, that's definitely part of the work. There is no good technobabble without a good set of new almost-meaningful words

So 'word building' definitely should be part of every curriculum about writing sci-fi

 

[DaveC426913]

TIL, that the magnitude of an Earthquake is not based on its severity - it is based on the length of the fault.

The largest earthquake in recorded history - a 9.5 - occurred in Valdivia, Chile, in 1960. It spanned one thousand miles.

The reason a Mag 10 quake cannot happen is because there are no faults anywhere in Earth sufficiently long - it would have to span a significant portion of the Earth's circumference.

 

[berkeman]

TIL, that the magnitude of an Earthquake is not based on its severity - it is based on the length of the fault.

The largest earthquake in recorded history - a 9.5 - occurred in Valdivia, Chile, in 1960. It spanned one thousand miles.

The reason a Mag 10 quake cannot happen is because there are no faults anywhere in Earth sufficiently long - it would have to span a significant portion of the Earth's circumference.

Source? I think somebody is pulling your leg...

 

[Klystron]

Source? I think somebody is pulling your leg...

Length of faults certainly a factor but quake magnitude involves a logarithmic scale measuring energy release. Earth science not my area, but grew up in California quake country.

https://en.wikipedia.org/wiki/Earthquake#Intensity_of_earth_quaking_and_magnitude_of_earthquakes

...Only in the last century has the source of such shaking been identified as ruptures in the Earth's crust, with the intensity of shaking at any locality dependent not only on the local ground conditions but also on the strength or magnitude of the rupture, and on its distance.[33]

The first scale for measuring earthquake magnitudes was developed by Charles F. Richter in 1935. Subsequent scales (see seismic magnitude scales) have retained a key feature, where each unit represents a ten-fold difference in the amplitude of the ground shaking and a 32-fold difference in energy. ... bolding added

Although the mass media commonly reports earthquake magnitudes as "Richter magnitude" or "Richter scale", standard practice by most seismological authorities is to express an earthquake's strength on the moment magnitude scale, which is based on the actual energy released by an earthquake.

 

[Oldman too]

TIL, GORT (yes that one) is an acronym for Genetically Organized Robotic Technology, pretty cool for '50's Sci Fi.

 

[fresh_42]

Genetically Organized Robotic Technology

And I thought those were Borg.

 

[Oldman too]

And I thought those were Borg.

I'm working out the acronym for that...

 

[Klystron]

I'm working out the acronym for that...

Not a trekkie myself, but my youngest sister definitely fills that bill. When Jean Luc was first assimilated, I figured Borg was short for cyborg, cybernetic organism, since they merged humans with computer machinery. Battlestar Gallactica, popular at the time, featured Cylons, so sis figured Trek NG writers dropped the 'cy-' to avoid comparisons and sound edgier.

Borg. Resistance is futile.​

 

[Hornbein]

The name of the Borg Seven of Nine may have been inspired by Ernest Borgnine.

 

[epenguin]

...that reminds me of how, as a child, I thought "impedance" was pronounced with emphasis on the "Im". Years later, when I said it aloud in a physics lab, I wondered why the tutor laughed...

In English English it is.
I can only guess why your tutor laughed, maybe it sounded like impudence?
Where is the rule that says one or the other in both cases?
Don't think there is a universal authority for them.

 

[NTL2009]

TIL that Mho's, a unit of electrical conductance, is just Ohm spelled backwards.
It also uses an upside down omega as its symbol, whereas Ohm's uses a non-inverted omega.
Conductance is also the reciprocal of resistance.
They just took everything about Ohm's and inverted them!

I always thought that was very clever, and it made me chuckle a bit, something needed in the often strict world of science/engineering. Unfortunately, the 14th General Conference on Weights and Measures lacked any sense of whimsy or humor. They officially replaced the Mho with siemens. Which is confusing, S for siemens, and we already have s for seconds. mS or ms?

https://en.wikipedia.org/wiki/Siemens_(unit)

The 14th General Conference on Weights and Measures approved the addition of the siemens as a derived unit in 1971.[1]

Along those lines, I was disappointed to learn that the word for "palindrome" in
Esperanto is not spelled the same backwards and forwards. What a missed opportunity!

palindrome Esperanto: palindromo

 

[DaveC426913]

Source? I think somebody is pulling your leg...

United States Geological Survey?
https://www.usgs.gov

Length of faults certainly a factor but quake magnitude involves a logarithmic scale measuring energy release. Earth science not my area, but grew up in California quake country.

https://en.wikipedia.org/wiki/Earthquake#Intensity_of_earth_quaking_and_magnitude_of_earthquakes

"The magnitude of an earthquake is related to the length of the fault on which it occurs. That is, the longer the fault, the larger the earthquake. ... No fault long enough to generate a magnitude 10 earthquake is known to exist, and if it did, it would extend around most of the planet."
https://www.usgs.gov/faqs/can-megaquakes-really-happen-magnitude-10-or-larger

 

[berkeman]

United States Geological Survey?
https://www.usgs.gov

"The magnitude of an earthquake is related to the length of the fault on which it occurs. That is, the longer the fault, the larger the earthquake.

Oh, that's different from what you said originally, IMO. Sure, the longer fault line will store more energy, all else being equal. But the magnitude of the earthquake is based on the energy released.

You originally said:

TIL, that the magnitude of an Earthquake is not based on its severity - it is based on the length of the fault.

That's what confused me.

 

[DaveC426913]

Oh, that's different from what you said originally, IMO. Sure, the longer fault line will store more energy, all else being equal. But the magnitude of the earthquake is based on the energy released.

You originally said:That's what confused me.

I'm afraid I am simply quoting from the government."The magnitude of an earthquake is related to the area of the fault on which it occurs - the larger the fault area, the larger the earthquake. The San Andreas Fault is 800 miles long and only about 10-12 miles deep, so that earthquakes larger than magnitude 8.3 are extremely unlikely.

The largest earthquake ever recorded by seismic instruments anywhere on the Earth was a magnitude 9.5 earthquake in Chile on May 22, 1960. That earthquake occurred on a fault that is almost 1,000 miles long and 150 miles wide, dipping into the Earth at a shallow angle. The magnitude scale is open-ended, meaning that scientists have not put a limit on how large an earthquake could be, but there is a limit just from the size of the earth. A magnitude 12 earthquake would require a fault larger than the Earth itself."I mentions nothing about the amount of energy released.

 

[berkeman]

I mentions nothing about the amount of energy released.

https://pubs.usgs.gov/gip/earthq4/severitygip.html

The Severity of an Earthquake

The severity of an earthquake can be expressed in terms of both intensity and magnitude. However, the two terms are quite different, and they are often confused.

Intensity is based on the observed effects of ground shaking on people, buildings, and natural features. It varies from place to place within the disturbed region depending on the location of the observer with respect to the earthquake epicenter.

Magnitude is related to the amount of seismic energy released at the hypocenter of the earthquake. It is based on the amplitude of the earthquake waves recorded on instruments which have a common calibration. The magnitude of an earthquake is thus represented by a single, instrumentally determined value.

 

[DaveC426913]

It would be nice if the government got its act together and defined its terms unambiguously. They appear to say two different things, both of which appear equally valid.

 

[fresh_42]

It is complicated. E.g. TIL that the Richter scale is a) empirical, b) only valid in a certain range of amplitudes, c) only for Wood-Anderson seismographs, and d) meant to be applied in Southern California only.

Earthquakes come in all sizes: seismometers in mines record micro-ruptures a few tens of centimeters in length, which correspond to negative magnitudes. A magnitude $2$ tremor can be felt close at the hypocentre, which is roughly the length of a rupture of a few tens of meters, a medium-sized earthquake breaks several tens of kilometers of a fault, while in large earthquakes such as the $1906$ $M7.8$ San Francisco Tremors on the San Andreas Fault, breaking several hundred kilometers at a time.
...
A quantity can also be derived from the seismograms recorded at the various stations, which is a measure of the energy radiated by an earthquake. This quantity is called magnitude, which is a logarithmic one and corresponds to the energy scale.
...
Over time, a variety of synonymous local and global magnitude definitions based on amplitudes of different seismic wave types have been developed and devices introduced. They are scaled so that they end up having similar numerical values. They fulfill the general form:
$$
M=\log_{10} \left(\dfrac{A}{T}\right)+Q(r,h)+a
$$
where $A$ is the measured amplitude in the seismogram, $T$ the corresponding time period,
$Q(r,h)$ is a correction term that depends on the distance $r$ and the depth of the focus $h$, and $a$ is an empirical constant.
...
However, this type of magnitude indication does not contain any direct information about the total energy of an earthquake, but only about the energy radiated in a certain frequency range.

https://ethz.ch/content/dam/ethz/sp...rvation_networks/F_Erdbeben_Skript_HS2014.pdf

Now follow some considerations about the dependency between magnitudes and total energy.

I read this as there is a certain dependency between the length of tremor in a fault and the energy involved. The magnitudes, however, are defined via measured amplitudes, time, and the location of the instrument relative to the earthquake. This allows some conclusions about the total energy.

So maybe we could get some statements along the line Length $\to$ Energy $\to$ Amplitude $\to$ Magnitude. But the definitions of Magnitudes are independent of sizes.

Last possibility: Swiss geophysicists use different definitions than American geophysicists.

 

[Drakkith]

I can only guess why your tutor laughed, maybe it sounded like impudence?

Impotence. Of the male variety.

 

[ergospherical]

 

[ergospherical]

My mother sent that to me. I sure hope it isn't some thinly veiled jibe...

 

[jack action]

TIL:

Imagine that it’s the middle of the night.

You’ve been driving for hours.

White line fever is setting in.

You hear a deep, dark, malevolent voice coming over the CB radio. It sounds so familiar.

You turn it up, not believing your ears as the voice of the evil “Darth Vader” from Star Wars asks, “What’s your 20?”

“Darth Vader” Chatted With Truckers On CB Radio​

According to interviews given by “Star Wars” voice actor James Earl Jones, this really happened to some truckers in the 1970’s, when CB radios were far more commonly used by both truckers and the motoring public.

After “Star Wars” premiered, Jones would get bored while driving cross country and would hop on the CB radio. Using “Darth” as his handle, he used to chat with truckers as he traveled the highways.

But Jones eventually caused so much CB panic that he had to give up the game. He said, “the truck drivers would really freak out—for them, it was Darth Vader. I had to stop doing that.”

 

[DaveC426913]

: desperately scrambles to find transportation-related puns for "I am your father" and "Search your feelings":

How about "May TransForce be with you"?

 

[BillTre]

from XKCD:

 

[Oldman too]

How about "May TransForce be with you"?

It could be "may the farce be with you"

 

[Oldman too]

TIL, that I don't suffer from Anhedonia.

 

[DaveC426913]

TIL, that I don't suffer from Anhedonia.

Well you ol' braggart you.

 

[fresh_42]

TIL what spamdexing is.

 

[pinball1970]

TIL, that I don't suffer from Anhedonia.

That's good to know! I suspected pleasure may be something to do with that word but I still had to look it up to check.

 

[Hornbein]

TIL, that I don't suffer from Anhedonia.

That word inspired the title "Annie Hall."

 

[pinball1970]

That word inspired the title "Annie Hall."

Really?

 

[Anachronist]

Today I learned that a single kiss may transfer 80 million microbes!

That explains why, whenever I started a relationship with a new girlfriend in my youth, I would come down with a cold 100% of the time after the first kiss. People are big bags of germs, everyone has their own unique collection of them, and in any new relationship I had to acclimate to the collection of my new partner. For some reason, the girlfriends never got sick.

 

[Astronuc]

Dostoyevsky, Just After His Death Sentence Was Repealed, on the Meaning of Life, by Maria Popova
https://www.themarginalian.org/2019/12/05/dostoyevsky-execution-life/

“To be a human being among people and to remain one forever, no matter in what circumstances, not to grow despondent and not to lose heart — that’s what life is all about, that’s its task.”

“I mean to work tremendously hard,” the young Fyodor Dostoyevsky (November 11, 1821–February 9, 1881) resolved in contemplating his literary future, beseeching his impoverished mother to buy him books. At the age of twenty-seven, he was arrested for belonging to a literary society that circulated books deemed dangerous by the tsarist regime. He was sentenced to death. On December 22, 1849, he was taken to a public square in Saint Petersburg, alongside a handful of other inmates, where they were to be executed as a warning to the masses. They were read their death sentence, put into their execution attire of white shirts, and allowed to kiss the cross. Ritualistic sabers were broken over their heads. Three at a time, they were stood against the stakes where the execution was to be carried out. Dostoyevsky, the sixth in line, grew acutely aware that he had only moments to live.

And then, at the last minute, a pompous announcement was made that the tsar was pardoning their lives — the whole spectacle had been orchestrated as a cruel publicity stunt to depict the despot as a benevolent ruler. The real sentence was then read: Dostoyevsky was to spend four years in a Siberian labor camp, followed by several years of compulsory military service in the tsar’s armed forces, in exile. He would be nearly forty by the time he picked up the pen again to resume his literary ambitions. But now, in the raw moments following his close escape from death, he was elated with relief, reborn into a new cherishment of life.

To be sure, Russia has a rich literary heritage/legacy.

 

[Klystron]

To be sure, Russia has a rich literary heritage/legacy

Unlike many/most of my contemporary literary friends, I prefer reading Russian / USSR science fiction to dull Dostoyevsky, too dated for my taste in literature although I have read the classics. I snatch English translations of Russian novels as they appear in my local library.

Take brilliant SF author Vladimir Sorokin. After reading his satirical "Ice" trilogy beginning with "Bro", depicting a Ukrainian protagonist out to save the world after falling on a frozen fragment of the Tunguska meteor, Russian atrocities in invaded countries appear inevitable.

"Blizzard" remains a satirical favorite with miniature horses, looming giants, tiny people and an eminently clumsy, if well meaning, doctor hellbent on curing a plague outbreak. "Day of the Oprichnik" must be one of the most sadistic cruel novels that I have read from any locale. Chilling, you will never look at Vladimir Putin or Russian oligarchs the same.

 

[Oldman too]

That word inspired the title "Annie Hall."

Great, now I'll be running Woody Allen skits in the back of my mind for a while, (everything you wanted to know, but were afraid to ask ?)

 

[Oldman too]

TIL what spamdexing is.

TIL, I hate spamdexing. Although it appears Doxxing can be useful when properly applied.
https://www.bbc.com/news/technology-60864283

The boy's father told the BBC: "I had never heard about any of this until recently. He's never talked about any hacking, but he is very good on computers and spends a lot of time on the computer. I always thought he was playing games."

 

[epenguin]

TIL that Mho's, a unit of electrical conductance, is just Ohm spelled backwards.
It also uses an upside down omega as its symbol, whereas Ohm's uses a non-inverted omega.
Conductance is also the reciprocal of resistance.
They just took everything about Ohm's and inverted them!

The unit etc. was in my first textbook, without explanation but I soon worked out how they came about. Never liked it, don't like jokey or slangy terminology. (But all my principles like that have exceptions.) This leads, through a thread you may be able to discern, this leads, to the neologisms, at least they were neologisms when they were new: "input" and "output".

I always thought these were very neat, natty, useful and indicative words with a self-explanatory character. Though sounding slangy. (Or, what is practically the same thing, I perceived a bit later, American. :) ) I could sense what they meant before I really knew. That was early on. My Dad was a radio/TV engineer (I was a disappointment) and I was seeing the term very early. almost as early as possible in fact. You would think it's currency started around the 1920s, but according to a graph in Oxford Languages Dictionary it seems to have, but with very very low frequency and does not start to be noticeable though still rare until the 1940s. I knew it not long after it started then. Since then the range of meaning has expanded - for a decision whatever like where to take the school's annual picnic you might be asked for your input.

'Output' is notably different from 'input' that way. As well as engineering you associate the word with economics etc., and it was already becoming fairly common before 1900.

'Feedback' is another originally technical word of which most of the above could be said. But according to the same above source usage of the first two peaked around 1990, that of 'feedback' which started around 1940 is still expanding.

I just thought you might like to know.

 

[Oldman too]

TIL, ORCs just may be the true Lord of the Rings.

https://www.nature.com/articles/d41586-022-00861-6
https://arxiv.org/abs/2203.10669
https://www.dropbox.com/s/ra4b6vk5uxaykg2/Meerkat_ORC1_paper__Revised.pdf?dl=0

 

[ergospherical]

 

[Klystron]

View attachment 299110

From their habits (brown robes), white cord, the monks are Franciscans, office of friars minor.

From the knots on his cord the doggie is third order, a lay dog, licensed to beg.

 

[berkeman]

If the doggie is not fixed already, that could be a problem with violation of his vows. Sorry doggy...

 

[BWV]

This number has not changed for any European country in over 300 years

 

[jtbell]

Today I learned that cashless ATMs are a thing. Instead of cash, they dispense pot, using a loophole to get around restrictions that are intended to prevent people from using debit or credit cards to buy pot via a retail point-of-sale terminal. The ATMs code the transaction as a cash withdrawal, instead of a purchase.

Visa cracks down on cashless ATMs at cannabis dispensaries (MarketWatch)

 

[Ibix]

This number has not changed for any European country in over 300 years

View attachment 299273

What happened 300 years ago? Divide by zero somewhere is the only thing I can think of, but the implications of that are pretty horrible...

 

[BillTre]

What happened 300 years ago? Divide by zero somewhere is the only thing I can think of, but the implications of that are pretty horrible...

Depending on how you count population and people, you might get numbers different from one in the US before the Civil War. Prior to that slaves were only counted as 3/5 of a non-slave, in the official census anyway.

 

[jbriggs444]

Depending on how you count population and people, you might get numbers different from one in the US before the Civil War. Prior to that slaves were only counted as 3/5 of a non-slave, in the official census anyway.

The legendary two headed man. One half person per capita.

 

[LCSphysicist]

View attachment 299110

He has become a jedi

 

[Drakkith]

The legendary two headed man. One half person per capita.

Goes well with the 2.5 kids every american should have.

 

[Oldman too]

TIL, α = 1/137.035999206
https://www.nature.com/articles/s41586-020-2964-7

 

[strangerep]

TIL, α = 1/137.035999206
https://www.nature.com/articles/s41586-020-2964-7

Once again, it gives me pause (for thought) that we have such a stunning theory of QED, yet still find significantly frustrating issues in galactic/cosmological dynamics.