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Lionel Mandrake

Lionel Mandrake's Journal
Lionel Mandrake's Journal
December 23, 2018

Some spectral colors are lighter than others.

Spectral colors are the colors of a rainbow. These colors are pure, not washed out, not pastel, not muddy. Yellow is often said to be the lightest. Certainly yellow ink or paint has little contrast with white. Nobody would prefer to read text printed in yellow on white paper. Blue seems darkest, with red and green in between. Why?

One explanation I have heard is that it's all about luminosity, the peak of which is about 555 nm for people with normal color vision. But the color with wavelength 555 nm is not yellow; it's the color called "bright green", which is greener than chartreuse. Furthermore the fact that blue is much darker than red does not show up in a graph of luminosity vs. wavelength. So the question has not been answered in a satisfactory way.

https://en.wikipedia.org/wiki/Luminosity_function

December 9, 2018

Morphology of "antidisestablishmentarianism",

an unusually long English word which means opposition to the separation of Church and State, especially in England.

According to Wiktionary,
antidisestablishmentarianism < anti- +? disestablishmentarian +? -ism.

The morphology is ambiguous, i.e., we could draw different trees. We could have either

antidisestablishmentarianism < anti- +? disestablishmentarianism
disestablishmentarianism < disestablishmentarian +? -ism
disestablishmentarian < disestablishment +? -arian

or

antidisestablishmentarianism < antidisestablishmentarian +? -ism
antidisestablishmentarian < anti- +? disestablishment +? -arian,

with another ambiguity. We could have either

antidisestablishmentarian < antidisestablishment +? -arian
antidisestablishment < anti- +? disestablishment

or

antidisestablishmentarian < anti- +? disestablishmentarian,
disestablishmentarian < disestablishment +? -arian.

According to Wiktionary, the rest of the morphology is unambiguous:

disestablishment < dis- +? establishment
establishment < establish + -ment,

but a possible alternative is

disestablishment < disestablish + -ment
disestablish < dis- +? establish.

The word is only slightly bastardized. Most of the roots are Latin, but the first and last are Greek:

anti- < Ancient Greek ἀ???-, and

-ism < Ancient Greek -???ό? or -????.

November 4, 2018

Names of sciences that begin with "Astro".

An educational song from "Sesame Street" goes like this:

"One of these things is not like the others,
One of these things just doesn’t belong,
Can you tell which thing is not like the others
By the time I finish my song?"

Here is a of things, one of which doesn't belong:

astrochemistry
astrodynamics
astrology
astrometry
astronautics
astronomy
astrophysics

Ironically enough, the thing that doesn't belong is the one most frequently abbreviated "astro". The other things in the list are respectable subjects one might study in a college or university. The one you are least likely to recognize (unless you have studied astronomy) is "astrometry". According to the dictionary on my computer, "astrometry" is "the measurement of the positions, motions, and magnitudes of stars".

What doesn't belong in the list is, of course, "astrology". Why doesn't it belong? For one thing, no reputable college would teach a course in it. It became disreputable during the 17th century and has remained so ever since.

What's wrong with astrology? Is it merely a scam? Is it a sign of stupidity? Is it a science that failed? Charles Day, who writes a regular column in the magazine Physics Today, had this to say in the October 2018 issue:

https://physicstoday.scitation.org/doi/10.1063/PT.3.4032?af=R&fbclid=IwAR2Q7BbJtPzRuUAbW4XxIlPOvAeewAqUYrZPBQgzQrvey4L-SCy1sYv1IcY

September 30, 2018

The unexplained marginalization of astrology

As a retired physicist, I like to read about the history of physics and of science generally. Since one type of history depends on another, I also read about political, religious, and other types of history.

Scientists of the past had to live under conditions I find hard to imagine. Galileo was threatened with torture and death by the "Holy Office" in Rome for the unforgivable sin of teaching that the earth goes around the sun. Kepler had to work like hell to defend his mother from a charge of witchcraft. Kepler didn't doubt the existence of witches, he just denied that his mother was one of them. Thus history of science is mixed up with history of religion and superstition.

The history of astronomy has an even more intimate relationship with the history of astrology. Astronomers like Copernicus, Tycho Brahe, Galileo, and Kepler lived in an age when astronomy and astrology were seen as indivisible parts of a whole. Astronomers were expected to, and did, cast horoscopes. King Frederick II of Denmark supported Tycho Brahe so that Tycho would cast horoscopes for the king's children. One of those children was crowned in 1596 and promptly kicked Tycho off the island, Hven, where Tycho had built an observatory and compiled observations of unprecedented accuracy. Tycho bounced around Europe for a while and ended up at Prague, where he met Kepler. That meeting led to Kepler's first two laws of planetary motion.

The scientific revolution of the seventeenth century coincided roughly with a marked decline of scholarly interest in astrology. Astronomy was no longer tied to astrology at the time of Christiaan Huygens and Isaac Newton, neither of whom ever cast a horoscope. It's tempting to say that advances in astronomy made astrology seem ridiculous, but historians have not discovered any evidence for this interpretation. I would like to know how and why astrology had been marginalized by the about 1650.

A conference on 'The Marginalization of Astrology in Early Modern Science and Culture' was held in Utrecht in 2015. Despite the extensive scholarship made evident by this conference, the causes of this marginalization remain unclear.

One of the papers from this conference begins with a telling anecdote:

"In 1659, the famous astronomer and mathematician Christiaan Huygens was asked to cast a horoscope for one of the princesses of Orange. The princes of Orange were his family’s main patrons and Huygens was therefore hardly in a position to turn down the request. However, he had to admit that not only he did not believe in astrology, but even that he had never occupied himself with it. He knew nothing better to do than to pass on the request to his friend Ismael Boulliau.

"It is perhaps not very surprising that Huygens felt skeptical about astrology, but it is remarkable that he was ignorant about it. After all, Huygens had had a full training in mathematical and astronomical theories and techniques. He had been taught at The Hague by Stampioen, at the University of Leiden by Frans van Schooten Jr, and later at Breda he had been familiar with John Pell. Yet in spite of all this training, he was not capable of casting a simple horoscope. Apparently, by the middle of the 17th century it was possible to be a first-rate astronomer and mathematician and not have the haziest idea about astrology.

"Less than 50 years earlier, astrological techniques were a self-evident part of mathematical training at Dutch universities. When in 1607 Isaac Beeckman asked the professor of mathematics at Leiden, Rudolf Snellius, for advice on the study of mathematics, Snellius gave him a list of books to study that included not only works of “Astronomia” (“Ptolomaeus, Copernicus”), but also “Astrologia” (“Ptolomaeus, Hermes”). Snellius praised the history and dignity of astrology in the preface to his commentary on Cornelius Valerius’s book on spherics."

- Rienk Vermij, University of Oklahoma, USA
http://journals.sagepub.com/doi/abs/10.1177/0073275314529862

August 21, 2018

The DMV is almost as bad as hospital ERs.

Waits of several hours are common in both of these broken systems. The ERs are a national disgrace, but the California DMV is our very own particular disgrace. A good question for any politician running for statewide office in California is: WTF are YOU going to do about the fucked up DMV? If the answer is to study it, then you should vote for someone else.

August 7, 2018

Limits of the visible spectrum

What determines the limiting wavelengths of visible light? Below about 400 nm., light is usually called ultraviolet (UV). Above about 700 nm., it's called infrared (IR). But why?

The link below shows a chromaticity diagram, the boundary of which has a curved part (corresponding to spectrally pure visible light) and a straight part (the purple line, corresponding to mixtures of red and violet).

In a normal adult human, the lens filters out most of the UV. Babies can see 300-400 nm. light, which is well into the UV. But they don't see new colors in this range. Spectrally pure UV produces the same sensation as visible light within the chromaticity diagram, i.e., not spectrally pure and not on the purple line.

The cutoff at the upper wavelength limit is more gradual. Retinal photoreceptors become less and less efficient at converting light into nerve excitations as the wavelength moves toward IR. Again, although we can sometimes see IR, we don't see new colors in this range.

https://scc.ustc.edu.cn/zlsc/sugon/intel/ipp/ipp_manual/IPPI/ippi_ch6/ch6_cie_diagram.htm

May 14, 2018

Apps that I can't get rid of

MacOS High Sierra comes with a helpful tip about 32-bit apps and a warning that future versions of OS X will not support such apps. The helpful tip reads as follows:

<begin quote>

How do I check if an app is 32-bit or 64-bit?

From the Apple menu, choose About This Mac, then click the System Report button. From the system report, scroll down to Software, then select Applications. When you select an individual application, you will see a field titled ”64-bit (Intel)”. “Yes" indicates 64-bit; “No" indicates 32-bit.

<end quote>

I followed the instructions above and got a list of the apps installed on my computer. It's nice to know which apps are 32-bit and which are 64-bit, but what's more interesting is this appears to be a complete list of all apps on my computer. I'd never seen such a list before.

Looking over the list, I see that many apps are obsolete. Some apps exist only to launch intrusive promotional crap. Many apps are not where the list says they are. I can't get rid of them, because I can't locate them.

Has anyone else run into this problem?

March 1, 2018

Trump is a man of faith. Who knew?

I always thought Donald was the earthly representative of Satan. But a new biography has set me straight. Should I ask Donald to forgive me?

http://www.latimes.com/opinion/op-ed/la-oe-downes-the-faith-of-donald-j-trump-20180301-story.html

March 1, 2018

Three-quarters of employees surveyed at Disneyland say they can't afford basic living expenses

Source: Los Angeles Times

Only weeks after Walt Disney Co. reported better-than-expected profit, a survey at the company's Anaheim theme parks found that 73% of employees questioned don't earn enough to pay for such expenses as rent, food and gas.

The online survey, funded by labor groups pushing for higher wages for workers at Disneyland and California Adventure Park, also said that 11% of resort employees have been homeless or have not had a place of their own in the last two years.

"Disneyland employees report high instances of homelessness, food insecurity, ever-shifting work schedules, extra-long commutes, and low wages," the study said.

The online study was conducted by the Economic Roundtable, a nonprofit research organization in Los Angeles, and the Urban & Environmental Policy Institute at Occidental College.

Read more: http://www.latimes.com/business/la-fi-disneyland-study-20180228-story.html



"The happiest place on earth" has a dirty little secret. Its employees are anything but happy, for a good reason. Don't go there. Don't buy the overpriced tickets. Don't subsidize a company that treats its employees so poorly.
February 9, 2018

Darwin Day is approaching.

Next Monday is Darwin Day. Charles Darwin was born on February 12, 1809. (So was Abraham Lincoln, but that's a whole 'nother story.) Various schools and organizations celebrate Darwin Day in various ways. It's all good.

Profile Information

Gender: Male
Hometown: The Left Coast
Home country: USA
Current location: electrical wires
Member since: Sun Jul 1, 2007, 06:47 PM
Number of posts: 4,076

About Lionel Mandrake

I study, play the piano, play chess and go, and enjoy the company of my wife, children, grandchildren, other relatives, and friends. I am a perennial student at a school where they let me attend classes and use the library for free (because I'm old). My serious reading includes math, science, history, and biography. I enjoy science fiction and mysteries, which my wife and I refer to as "mind rot". And now on to politics. I hated Nixon and Reagan. I think W is a war criminal and was easily the worst president in US history until Trump came along. Trump and Sessions should be tried for having separated small children from their parents, which was a crime against humanity. I will support any candidate who is a "dove". I support "plan B" without prescription for girls of all ages. I support free abortion on demand, without delay, and without the requirement to notify anyone, for all women and girls who want it. I think it's time to repeal the Bush/Trump tax cuts for corporations and the very rich.
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