I don't know if the couple in the first photo are flat-earthers or just t-shirt models, they're not the subject of this post, only the claim on their shirts is.
You frequently see things on forums like "once you go flat, you never go back" ...
.. so even one counterexample refutes that. One often sees responses to these counterexamples (for example, in a comment to this post), that these people were never really flat Earthers, but they never post any evidence other than their having left flat Earth, see the No true Scotsman fallacy.
To save having to look for the details each time someone claims this never happens, I'm putting them here.
The first two former flat Earthers (FFEs) appeared on the SciManDan Podcast but they also show up again in the FTFE playlist at the bottom of this article.
I had previously written that his name was Frank DiLeonardi, but Craig corrected me in a Facebook comment. Now I'm wondering who Frank is and where I got his name and whether he has anything to do with this at all.
And this is Ranty (Flerfspective, this channel isn't available now, I don't know what's going on) who describes himself as a recovering flat Earther.
Here is a video about a FFE who goes by the name "Johnny Orbital"
Here's a playlist, Interviews with Ex Flat Earthers, (currently 7 videos, although the last one is numbered 8) by FTFE (Fight The Flat Earth). In addition to the previously mentioned STST and Ranty, it also has discussions with four more FFEs, Clear Cognition (Adam Doughty), Sean G, Blu, Jose G Gonzalez, and Promethean Kitchen. Update: since I last looked at this playlist, added several short clips Rachie 00000 (see next paragraph)
YouTuber Rachie 00000 is another former flat-earther. Here's a sample.
Another post in my series of "I am tired of answering this question and wrote this so I can just paste a link to it.
The why is, I am mocking something. Very often I will have taken some @*#$*@ nonsense and transformed it into worse nonsense. To put it another way, if you say something willfully ignorant, I assume that your native language is gibberish am trying to talk to you so you'll understand.
Now to the how.
The simplest method is just to hit keys at random.
A method that generates texts that almost look meaningful is to use my phone's predictive text and just accept one of the suggested words or emojis at random. If a phrase emerges from the randomness it may be because my phone has learned to recognize frequent word-pairs, e.g. personal incredulity.
Sometimes I'll copy the text to which I'm responding, paste it, and mangle the words. I will sometimes free-associate into song lyrics, pick similar-sounding words, any meaning you think you detect is probably apophenia.
And then there are gibberish generators. Lorem Ipsum generators. general gibberish generators, scientific nonsense generators. The disassociated-text command in Emacs or websites that do something similar.(these also take the text I'm mocking as input). Sometimes, if what I'm satirizing is in a language other than English. I'll see if I can find a nonsense generator in that language, here's a recent French one that I used.
I've gotten tired of retyping this, so here's a copy to post the next N times I see some flerf claim that it does.
First of all, even if it did, it would matter no more than what the Chevy Nova means in Spanish (also, that didn't happen, see Snopes on Did the Chevrolet Nova Fail to Sell in Spanish-Speaking Countries?). But if we were going to try to interpret its acronym in Hebrew, it doesn't mean "to deceive" but something much better. Keep reading.
They usually refer to The Exhaustive Concordance of the Bible by James Strong (often called Strong's Concordance), it's a useful reference work, and it's found on many sites that deal with the Bible, e.g Bible Study Tools, Bible Hub or Study Bible, which I'll link to below about the particular words in question. It has an entry for every word in the Bible, words labeled with H are Hebrew or Aramaic, those with G are Greek, and that letter is followed by a number. Words derived from the same root are found under the same entry. The concordance is old enough to be in the public domain, and there are many printed versions.
A slight digression, there are two Hebrew letters, Sin (nothing to do with the English word) and Shin. They look very similar, Sin has a dot on the left, שׂ, and is pronounced 's', Shin's dot is on the right, שׁ, and is pronounced 'sh'.
Now the word the flat-earthers refer to is H5377, and while the preceding link transliterates it nâshâ, there seem to be some printings that wrote šwhich is used to represent the sh sound. There's probably an explanation of all the diacritical marks (that one is called a caron) somewhere in a printed copy. This image of that edition often accompanies the claim. So it could be that the first person to make it was confused rather than lying.
The word that sounds closer to NASA, as it's got an s rather than a sh sound in it, is H5375. And while, once again, it doesn't matter what an acronym in one language sounds like in a different one, this one meaniing (among other things), wait for it, "to travel" and "to lift up". I would know this even if it wasn't at the link because I speak Hebrew, but even if I didn't, I once saw that my rabbi had an outline of a wedding sermon in the little book he carried to diverse ceremonies, weddings, funerals, et. al., listing those two, as well as "to marry" (Strong lists that, but I don't think it's used that way in the Bible) and "to forgive". You can probably reconstruct the whole sermon on your own.
ETA: Usually posting this gets silence or someone just repeats one of the claims, but here's a reply it got in 2018Flatearth: "The Acronym N A S A was taken from the Hebrew word Nahash which means serpent (snake emoji)hence the serpent tongue in the logo." I responded that the letter in Nachash is a hard ch, not an h, and NASA sounds even less like that than it does like Nasha.'
NASA's own explanation of the red shape is "The red v-shaped wing represents aeronautics"
A flat-earther (or perhaps a bible-thumper who took a wrong turn at Albuquerque and wound up in a group where flerfs post their nonsense and are mocked for it) posted this gem at me, by a user who goes by MARK13RECORDS.
It starts with an entry from Strong's Concordance, a serious work of Biblical scholarship, most often seen online with flerfs lying about what NASA means in Hebrew (short version, they confused H5375 with H5377, NASA isn't spelled like either of those words in Hebrew but is נאסא, but if it was Hebrew, ignoring how it's spelled, it would mean "to lift up" or "to travel"). This time we're dealing with H7017, Kenite (well that's at least the correct entry in Strong's) which is the name of a tribe in the Bible, and if you click on the previous link you'll see all the times it appears in the Bible).which Strong seems to be saying is the same *name* as Cain, the archetypical murderer in Genesis, or maybe that the founder of the tribe had the same name. It seems rather unlikely that a tribe that was around at the time of Moses would be descended from the original Cain, only Noah and his family survived the Flood, and they were dependents of Seth, not Cain.
Well there's a Jewish source identifying Noah's wife with Naama (at 22:00 or so he mangles that as Nāyama), the sister of Tubal-Cain, and a descendent of the original Cain, but tribal identity is patrilineal. Also, if Noah's wife was a descendent of Cain, and one takes Genesis literally, not just the Kenites, but all of humanity is descended from her. Of course if one does not understand Genesis to be historical, none of this matters.
The sons of Cain, the video says, without a source, carry out the negative parts of God's plan, and in direct contradiction to Genesis 4:1, claims Satan, not Adam, was Cain's father. Always nice when a bible-thumper lies about what their favorite book says.
And he lies again, when he claims that in John 8:44 Jesus said to the Kenites "ye are of your father the devil". Here, read the whole chapter and find the word Cain or Kenite.
Now he tries to prove that Satan is Cain's father. He identifies Satan with the serpent of Genesis, let's give him that one. So in Genesis 3, the serpent convinces Eve to eat the forbidden fruit (not identified as an apple, by the way). As part of their discussion, she says that God commanded not to touch the tree (not true, but we don't know if that's her mistake, or what Adam told her) and String H5060 says that this is a euphemism for sex. Well, that probably works in any human language. And most of times the word appears (again, full list at the link) it means simple touch. But still, no one had sex with the tree. Although Rule 34. And the old dirty joke about the minor who was told to practice with a tree.
Hold on, somehow Satan is not just the serpent, but also the tree. There's a quote from 2 Corinthians 11 about Satan beguiled/seduced Eve to eat the not-an-apple, but he thinks that means he had sex with her. I'm sure there's Groot porn but I will not look for it. He does notice that Adam also ate, but somehow spares us Satan and Adam sitting in a tree, K-I-S-S-I-N-G.
I'm skipping a bunch of verses that don't have anything to do with the paternity of Groot Jr, but he's got something against new biblical translations. Well why doesn't he just learn Hebrew, Aramaic, and Greek and read it all in the original? There aren't many Kenites these days but they use technology to corrupt people, which is why I suppose this guy made a YouTube video. And somehow counting the seals in Revelation has something to do with pebbles (huh?) and counting (is this another Strong's ref? he didn't give a number) has to do with stones, maybe the stones are being used to keep track of the count, and 666 is a number, so the stones are the Kenites, the offspring of Cain. Got that? I didn't.
Satan, he says, is called the king of Tyrus in Ezekial 28, but even in his favorite King James Bible, that's the actual ruler of the city of Tyre whose name does actually mean "rock".
Well he does get to Genesis 4, and actually quotes it. It says, in the KJV, that Adam knew his wife, she conceiver, and bore Cain. So he thinks the Bible is lying here, Cain was already conceived in the previous chapter? He goes on lying that the explanation of Cain's name, " I have gotten a man from the Lord" but the text on his screen has the word "against" in place of "from". In a different font, conveniently. He says this is from the Hebrew, but that's another lie. What it says in Hebrew is "I have acquired a man את the Lord". The Hebrew word את generally means nothing at all, it's just used before a definite article, for example, were I to say in Hebrew, I fisked this video, I would put את before the word meaning "the video" (in Hebrew, the definite article is a prefix, not a separate word). It can also mean "with", and that is how his inerrant, except when he thinks he knows better, KJV translated it. I suppose I'd have to invent a Hebrew verb for fisking, it's got the right number of consonants, but which conjugation-form to use? It also does have a lot of other meanings, we'll get to it later on when he gives its Strong's number.
There's a slide here about heteropaternal superfecundation, which is when twins have different fathers. It's the only explanation of what happened here, he asserts without evidence. The Bible doesn't even say Cain and Abel were twins. It does use the word "twins" about other pairs, Jacob and Esau, and Peretz and Zerach.
So after Cain slays Abel, he becomes a wanderer and vagabond and the mark of Cain and the mark of the Beast are somehow the same. And the first thing Cain did was build a city, so cities are bad. Some hilarious attempts to read how Cain's descendants names are transliterated follows at around 19 minutes in. Despite that city,, they're still vagabonds (all it says is that one of them, Jabal, that's how the KJV translates it) was a cattle-raiser who lived in a tent. But cities are bad? And leaving them to raise sheep is also bad? "Cattle" is what the Kenites call the "so-called gentiles". I know (and don't use) a number of pejorative terms in Hebrew and Yiddish for people who aren't Jewish, none of them mean "cattle". Oh, he knows one of them, too, at 20:20. But it doesn't mean cattle. The actual tribes of Israel, he says, think the Kenites are God's chosen people.
I wonder who he could possibly mean .... Oh, just in case it wasn't obvious he quotes Rev 3:9 about the "synagoge of Satan, which say they are Jews, and are not". But he doesn't preach hatred of Jews, just count those stones (still not getting that reference).
After some more fulminating about Lamech being another murderer, h's back to the slide with the spurious word "against" pasted in Now he's trying to support this lie with a slide giving various things the Hebrew word את can mean, let's see if it's Strong, again. Yep, H854. So out of 809 occurrences, it means against 36 times. And this isn't one of them. If the KJV translators thought it did in Gen 4, they would have translated it that way.
So, pulled straight from his ass, "the scribes and Pharisees" that Jesus opposed are the Kenites. Still no explanation of how they survived the Flood. Also the one-world government, the Illuminati. Wait, are human-serpent people lizard people? The horn of the he-goat is the United Nations. But there's more, the lion in Daniel is the Christian nations, the bear is the Communistic (sic) and Islamic ones, the leopard is the Kenites.
By the time of Newton it was already known that the planets revolve around the sun, with measurements, and it was possible to predict where they would be in the future (flerfs just say "nuh-uh" but can't predict the location of planets, even if they are just "lights on the dome"). What Newton added was an explanation of why it works like that.
Starting with the First Law of Motion, since objects move in straight lines unless acted upon by a force, there must be a force acting on the planets, directed towards the Sun. The same is true of the Moon orbiting around the Earth. Newton tried various models for this force, the only one that could produce results consistent with observations was proportional to the masses of the two bodies and inversely proportional to the square of the distance between them. The equation for this is F = Gm₁m₂/r², where the m's are the masses of the two object, r is the distance between them, and G is measured by experiment, not predicted.
As it's always been measured to be the same, it's known as the gravitational constant and was first measured by Henry Cavendish in 1798 in an experiment that is often discussed in this group. Since gravity is a very weak force, it's necessary to use heavy weights as the two masses and eliminate air movement and vibrations. The book gives a measurement of G from 1942 as 6.673E-11 N m² / kg². That N stands for newton, the measurement of force in the metric system
(You've really made it in science if they don't just name the law after you, but also one of the variables in that law is measured in you's. This reminds me of how in Jewish sources, authors are sometimes referred to by the name of their book, rather than their own name, and a story about a professor who said that you may use the textbook on the final name, but he said the name of the author instead of the textbook, so one student got help from the author. For example, I've got a copy of "Bueche" in front of me right now, but if someone said you could consult Bueche (before 2015, when he passed away) it could be understood to mean either his textbook or the agent, settler, or even the person. I couldn't find that story, but I did find one of a student who was allowed to bring notes on a 3x5 card, and he did, only it was measured in feet rather than inches. I had a roommate in college who was allowed a single piece of paper, so he used a piece cut from a roll of paper that was intended for a computer plotter, which may have displayed less ingenuity than the friend in highschool who owned a photo enlarger and would make really tiny cheat-sheets. I'm not going to name you, even though I think the statute of limitations has run out)
Back to physics, once we have measured G, we can calculate the mass of the Earth. Without putting it on a scale in front of your eyes. The other values we need are the acceleration of falling objects and the radius of the Earth (thanks Eratosthenes).
Next is a section on how the laws of motion apply on an incline, but that's just trigonometry so I'm going to skip it.
Finally, projectile motion. This is for trajectories short enough for the curve of the Earth not to be noticeable. I suppose we should be glad that flerfs aren't trying to lob projectiles many miles and see where they land ...
For example, a baseball player (this reminds me of an exam I was one involved with in college, the had set up one of those "Physics for Poets" (in this school it was probably pre-laws and pre-MBAs, as pre-meds had to take standard science courses, and I didn't get an A in inorganic chemistry and the associated lab just to mess with the curve, that was just lagniappe) and there was a probability question involving playing cards and some students who got the wrong answers tried to blame it on that they didn't know how many cards were in a deck or suit) throws a ball, it is accelerated downward, and travels horizontally at a constant speed (these calculations will be simpler if the wind isn't blowing, and we can ignore friction from the air over the distances baseballs can be thrown, and this is why Superman should umpire rather than play) until it hits something.
So we use linear horizontal motion to compute the horizontal motion, and uniformly accelerated motion for the vertical part and can compute things such as how fast the ball is moving at any point, where it hits the ground, and how much time it takes until that happens.
It happened like this, a member posted this diagram, which points out that FE maps are not useful for navigation in the Southern Hemisphere.
And a flerf responded with that video, saying How to use Gleasons why it's correct. You gotta use that maths stuff and not the purple stuff.
So I watched the video. Here's my response.
One fisk, coming up So we've got a YTer who calls himself Immune2BS. On first thought, is he also an anti-vaxxer? Well looking at the rest of his channel it would seem no, he's a one-conspiracy guy. So let's hear what he has to say.
He says he will explain why the Gleason map is accurate. He compares Australia on Gleason and Google Earth, or the globe if you will. They look different (we noticed). But the features of Australia are the same on each map, and he points to something near the Tropic of Capricorn meets the west coast of Australia, and everything has the same coordinates (yes, Gleason has the same coordinates for everything, it wouldn't even be a map projection were that not true). And the same thing happens where the tropic "exits out" on the west coast (he sounds surprised). And this also works where 135°E meets the south coast. How can that be? Gleason looks like a clock and there's that think in the center that moves and indicates latitude. He superimposes circles every 15° from the North Pole (but takes a lot longer to say that, because he mentions the value of every stop from 90°N to 60°S when there's a skidding sound) Whoa! What happened here? There's more Earth the further south you get, and "when somebody decided to create a globe out of the flat earth" they had to elongate and stretch to make it work because there's 15° missing of latitude.
(I really don't know what he's going on about, 75°S is on the Gleason map. I listened to that part twice to make sure he was saying it. The lines of latitude aren't marked around Australia, but they are along the line of longitude that runs thru Greenland, which Gleason labeled 2PM. 75°S passed thru Antarctica on both his map and on the globe as well as any other projection on a map., see image below, it's from a better image of the map, but the very same map with the Boston Public Library stamp on at 3PM it that I found online. And it's hard to see in the blurry image that YouTube displays, but HIS map also has the same numbers at 2PM, he just didn't notice them)
From what he can tell, and this is just conjecture (his word) they started from the top, the North Pole area and everything got stretched as they got down to the quote unquote South Pole. Everything about this map makes sense. It is a clock and so is the world because the day is 24 hours. Even time zones make sense. He shows an image of the actual time zones and asks which makes more sense, that or this (but fails to explain why he thinks Gleason makes more sense).
Here are two details of the Gleason map, found here. In the first image I added a red arrow pointing out where he can't find 75°S on it, the second is a bit further zoomed out to show the library stamp, this is the same map as in the video.
Now he switches to a map made by someone called Tiger Dan (this video was made in 2016 so perhaps people who followed this debate then knew what this was, all I can tell is it has some airport codes added to it and Mr. BS calls it a fiasco) but it looks like Dan tried to make landmasses from a globe or some other projection work on a Gleason map.
Then there's someone named Brian Clark who supposedly found a flat earth map from 1920 in the Library of Congress (supposedly? Here it is on the Library of Congress site and it has latitude lines all the way out to 90 (once again, so does Gleason, but what's he saying, the LoC map was faked?).
I split this up over several days, the only response I got from a flerf was "Falling in a circle.. lol", to which I responded that circular motion isn't until Chapter Eight
The Discovery of Physical Laws. No equations, just an essay. Physical laws are how we express how things behave. The purpose of research in physics is to discover them. We sometimes make mistakes, in which case we haven't discovered laws of nature, for example, Aristotle's belief that it was a law that heavier objects fall faster than light ones.
Even Galileo's law of falling bodies was incomplete, and doesn't work under conditions not available to him, but it was correct under the conditions under which he performed experiments. That's true of laws we discover, they well may be updated later on as we obtain new information.
But rarely is an accepted idea found to be entirely wrong (such as Aristotle's law of falling bodies), it usually needs to be modified to fit new discoveries, not entirely discarded. Newton was wrong about some things. So we don't accept a law because a famous scientist promoted it, but because it's been confirmed by experiment.
So Newton's first law of motion. A lab instructor may not injure a human being or, through inaction, allow a human being to come to harm. Sorry about that, I'll try again.
OK, let's try the translation of Newton's words from Latin in his Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy) that appears in the textbook: "Every body perseveres in its state of rest or of uniform motion in a straight line unless it is compelled to change that state by forces impressed thereon". That might be a bit tightly packed, so let's take it apart.
"at rest" means not moving. If it's not moving, and nothing makes it move, it's not going to start. If it does so repeatedly, physicists will be all over it trying to figure out what made it move.
"uniform motion in a straight line" is the sort of motion described in the first two chapters. IRL things moving in straight lines will eventually slow down and stop due to friction (which will be covered later in this chapter), running into something (such as the walls of the lab room), falling off the table, hitting the ice wall (not really). But as we do an increasingly better job of reducing friction, objects travel for longer before they noticeably slow down.
What's not explained in the translated quote is "forces impressed thereon". Well since it wouldn't do to not have any equations, I went to Wikipedia and found this one, but it involves calculus, so I sneakily removed it.
Σ𝐅 = 0 ⟺ 𝐚 = 0 (the part to the left of the double-arrow was covered in my OP, it means that sum off all forces, expressed as vectors, is zero, or the forces all cancel out, there's no difference if there are no forces, or someone applies a force one one side and someone else applies an equal force on the other side, or there are dozens of forces at all different angles, but applying vector addition gives zero. The double arrow means that if the condition on the left is true, the right side will be observed, and also the other way around. The right side says that there will be no acceleration, if it's at rest it will stay at rest, if it's moving at a constant speed in a straight line, it will go on doing that).
The book goes on to the Third Law (which isn't about lab assistants from protecting the lab from harm) before the Second (which isn't about lab assistants following orders of any tenured member of faculty) but I'm not having any of that. Wikipedia's expression of it in words is also easier to understand, "the rate of change of momentum of a body over time is directly proportional to the force applied, and occurs in the same direction as the applied force." Let's simplify matters and say the mass of the object isn't changing (it's not a melting ice cube or an airplane whose mass is reducing because fuel tanks are emptying) and the equation is
𝐅 = m 𝐚
It's necessary to explain the difference between weight and mass. mass is a more fundamental property of an object than weight. If you schlep (that's a technical term) an object to the top of a tall mountain, managing not to drop it along the way, it will weigh slightly less (why? the answer will astonish you!) but it will have the same mass, as can be demonstrated by trying to move it horizontally, it will take the same force to get it to accelerate by the same amount. This could also be demonstrated by a skydiver who had enough time to perform an experiment before it is time to pull the ripcord. To convert weight into mass, you just divide by the
The Third Law states that if object A exerts a force on object B, object B also exerts an equal and opposite force on object A.
Finishing up chapter 3, the force of friction is computed as f = μN where μ is the coefficient of friction (which varies according to the substances that are rubbing against one another, there's a chart that goes from wood over snow, about 0.06 to rubber over dry concrete, 0.7 to 1.0) and N is the normal force. "Normal" here isn't using the most common definition of the word but means perpendicular -the force exerted by the object on the surface on which it is traveling (and returned by the surface according to the Third Law of Motion) is at a right angle to the motion of the object across the surface. If the surface is level and the object is being pulled or pushed straight on (in the direction that it travels) the normal force is just its weight. But if it's being pulled at an angle, say a wagon that sits 8 inches off the ground pulled by a handle or string at an angle, or the surface is inclined, you'll have to use some trigonometry to calculate it.
It should be noted that there are two types of friction, kinetic, also called dynamic (when the object is moving) and static (just before it starts to move) which is higher, you may have noticed that it takes more force to start something sliding than to keep it moving. The examples of μ were for kinetic friction and the two coefficients of friction are labeled with subscripts, μₖ and μₛ.
Terminal velocity explains why Aristotle was wrong about light objects falling, the fall of objects is opposed by air resistance, which is greater for a light object and/or one with a large surface, and it also increases as the object moves faster, so eventually the two forces will have the same value (but in opposite directions) and the object will stop accelerating but fall at a constant velocity, known as terminal velocity The textbook doesn't explain how to calculate this velocity but gives some examples, a raindrop at 25 ft/sec, a person at 250 and points out that this will depend on the shape and orientation of the object, so if you're falling out of an airplane, how fast you'll be going before the sudden stop at the end depends on whether you are falling feet (or head) first or are prone and allowing you to try that yourself would violate the First Law of Lab Instructors as previously stated. But if you want to know how to compute terminal velocity for things other than yourself or your annoying roommate, see here
Average speed is defined as distance traveled (or driven, if sovcits were around when this book was written neither the author nor I had heard of them yet and the book uses them both) divided by time. Symbolically, ū = d / t. The bar above the u means that it an average - if someone traveled ten feet (are we going to stay in English units throughout the book or switch to metric at some point?) in two seconds, they didn't necessarily at 5 feet/second for the entire two seconds, but that is their average speed.
Now to velocity, the average velocity vector 𝘃̄ which is the displacement vector divided by time (we covered displacement vectors in chapter 1, see "driving 30 miles east".
If we want to measure the speed or velocity at a particular instant, and we're not Zeno, we don't find it impossible to compute it. Since we're not allowed to divide by zero (they taught you that in math class, right? Don't do that, that's where black holes come from) what we do is *almost* divide by zero, we measure the distance traveled over increasingly smaller intervals, and as ∆t (the interval) *approaches* zero in the above equations we approach an instantaneous speed.
If you want to know more about this, you probably should be taking Physics with calculus, but this textbook is for Physics without calculus.
Well now we can define acceleration (and with autocorrect we can even spell it), which happens when an object changes its velocity. It is that change in velocity divided by time, 𝗮̄ = (𝐯 - 𝐯₀) / t, where 𝐯₀ is the velocity at the start, and 𝐯 is the velocity at the end (of time t).
Since the velocities are vectors, so is acceleration. This chapter only deals with motion in a straight line, no curves or turns.
There's a long note about understanding equations instead of just memorizing them and one thing I want to mention is the suggesting there about examining the limiting form of equations, the example they give is that if acceleration is zero, 𝐯 - 𝐯₀ must also be zero, so 𝐯 = 𝐯₀. Yes, that should be obvious, and if the equations give a result that isn't, we have to reconsider whether the fault is with the equation, how we applied it, or with our sense of what is obvious.
(A joke, not in the book: A professor was notorious for leaving complicated demonstrations to the students, with no more than a remark that "It is obvious that..." One day a student interrupted. "Professor, is it really obvious that the second line follows from the first?" The professor looked at the board, wrinkled his brow, paced about the room for a few minutes, then, triumphantly said, "Why yes, it is obvious." In another version he goes back to his office for most of the class and appears breathlessly just before the class ends, with the same conclusion)
OK, now we get into dangerous territory, Galileo's observations about, um, things fall down go boom boom. (there is a hilarious video by a flerf who can't understand how gas gradients work and doesn't believe in gravity, that's something he kept shouting during the video. I think it was at a fellow flerf who was trying not to be quite as ignorant) While Aristotle thought that heavier things do that faster than lighter ones and for about two millennia that was accepted as fact (Aristotle lived 384 - 322 BCE, Galileo 1564 - 1642 CE), Galileo conducted experiments. He increased the time it takes objects to fall by rolling spheres down a slope, we reproduced this experiment in the course where I used this book, and to quote "it is not unlikely that in you laboratory work you will perform an experiment to check his results").
For whatever reason (scientists are baffled!) things fall down at close to 32.2 feet per second squared. Or 9.8 meters per second squared. So here's a sample problem, a stone is dropped from a bridge over water It takes 3 seconds for it to hit the water's self-seeking level So a (don't worry, I'm not calling it g) is 32 ft / sec², v₀ = 0, so the distance is ½at² or 0.5 * 32 * 3 * 3, or 144 seconds (see last equation below)
To sum up, here are all of the equations in scalar form (the same thing happens with vectors but the book wrote them as scalars and I'm tired of going to the site that turns text bold.
s = v̄t (displacement is average velocity multiplied by time, This is the definition of average velocity, rearranged to have displacement on the left side of the equation instead of velocity)
v̄ = ½(v + v₀) (average velocity is the sum of the starting and ending speed divided by two)
v = v₀ + at (final velocity is initial velocity plus acceleration multiplied by time. This is the definition of acceleration, rearranged)
v² = v₀² + 2as (this one is a bit more complicated, we take the definition of average velocity (v̄, two equations above) and plug them into the average velocity equation, the first one in this comment, to get s = ½(v + v₀)t, then replace t by its value from the definition of acceleration and get s = ½(v + v₀)(v + v₀)/a and rearrange that to get v² - v₀² = 2as and then move the v₀² to the right side. Wow, all that algebra we studied turns out to be good for something.
Because reasons, I'm a member of a group called Official Flat Earth & Globe Discussion, where flat-earthers (or people who think it's funny to pretend to be flat-earthers) post stupid things, get quickly refuted, but don't understand it, or people who've studied science write about science and the flerfs respond with laugh reactions, incomprehensible memes, quotes from Scriptue, and "nuh-uh". One of the things is that they don't just disbelieve that the Earth is a sphere (or a sphere that's slightly wider around the equator than around the poles, or even one that's slightly larger in the southern hemisphere than the northern), they also don't believe in gravity. So I decided to teach an introductory physics course there to see if they disagreed with anything else.
I only got one response to the first chapter, and it was questions about God, so I blocked the idiot. So anyway I'm going to post them on my wall too, because why not? I'll use the hashtag #PhysicsForFlerfs
So I went to find the simplest science textbook on my bookshelves, I picked Principles of Physics, F. Bueche, 2nd edition, 1972 which is for a general physics course without calculus. If I had taken physics at engineering school there would have been a higher-level course but I did my basic sciences at a liberal arts college where this is what they used.
So let's start in chapter 1, "Vectors and Balanced Forces".
An example of a vector is given as driving 30 miles east, it includes both magnitude (the 30 miles) and direction (east) as opposed to a scalar, e.g. driving 30 miles but not specifying which way. It gives several examples of vector addition, for example if someone goes 30 miles east and then 10 miles north, the Pythagorean theorem shows that they've gone the square root of 1000 miles, and drawing a scale diagram and using a protractor (not even trigonometry until a few pages later) shows the angle.
There are also examples of forces expressed as vectors. Let's leave out things we disagree about and do them on a table. If several forces are applied to an object, say it is being pulled on via strings from various directions, the total force can be computed by adding all the force vectors.
Quantities that are vectors appear in boldface, for example a force will be written as 𝐅
Now we get to to an object at rest. If all the forces on that object on a table are balanced, say one person applies a force of 10 pounds from one direction, and another does the same from exactly opposite the first, it won't move. This can be expressed in an equation, an object is at equilibrium if Σ𝐅 = 0, the Greek letter indicates "the sum of" so if all the forces add (via vector addition) to zero, the object won't move, or if it was already moving, it will continue to move as it would without those forces.
A flerf (flat-earther) posted this video to Official Flat Earth & Globe Discussion. It's 5 hours (!) long, but I'm listening to it at double-speed. The channel it's on is called Flat Earth Sun, Moon & Zodiac Clock app and was made by "a guy named Ewaranon" who used to have a channel of his own on YouTube but it's now deleted.
15 seconds of silence because dead air is cool. Actually better than "Greensleeves" which plays behind the drone of his voice and goes on for a while. I. Can't. Listen. At. The. Pace. He. Talks. At, so I'll be listening at double-speed.
Once you are awake it's hard to fall back asleep (but watch this video, maybe you'll get bored). Cartoon of the snow globe. Blather about satanic scientific priests (pics of Neil deGrasse Tyson, Brian Cox, Stephen Hawking) not being reliable. Drawing (not to scale) of Solar System. The barbaric mining of Earth's once-majestic giant trees (pic of a geological formation, so we're going to cover all the crazy here)
If they lied about all of the above how can we trust them about anything? (Well maybe first prove that they did?)
The first power tool was invented in 1895. So how were ancient buildings constructed without power tools? (I am not making this up). Step wells (cool pics, but what's the problem? yeah, takes longer using hand tools, but that's all, guy who most certainly could not have created the app he's selling). Giant canal networks So I looked up the Erie Canal, that predated 1895, but while I was doing that, he said it was allegedly built in 1825 and then he starts reading from Wikipedia about how the engineers were novices and not trained as civil engineers. (So he's claiming it was built by aliens or ancient humans and no one noticed it was already there when they went to build it?)
Same claim about castles. Did you know most were built without plumbing or heat? (do you even have a point?) And the impossible pyramids, and apparently slavery never happened (scholars now believe that the pyramids were not built by slaves). And air shafts align with stars.(so?). And he's got some problem with bastion forts (the geometry is better than he can draw freehand?) They couldn't see them from above, and we couldn't do this today (he couldn't). This is as silly as the heliocentric model (oh right, didn't I start watching a flerf video?)
So on to his explanation for all the thing he can't understand. Ancient civilizations used flat-earth (henceforth FE) to do all this, and our history is only 200 years old. Does he sound mad? (yes, why did you even need to ask). So you have to swallow this load of unsupported assertions to understand FE. We cannot waste time (which is why this goes on for FIVE HOURS) and he can't tell the truf in a linear fashion. A lot of history is guesswork (what then would be the right label for this? Historical dadaism?). A quote from "a so-called Napoleon" about history being agreed-upon lies.
Oh, good, he's run out of Greensleeves. Now he's got some chord progression in a loop.
1860 in St. Petersburg. 500,000 people lived there but where are they? (maybe because photos took a long time to expose then so they either took the photos when the streets were empty or kept people out, to avoid blurs as people moved during the shot?). A shadow shows it's early morning or late afternoon, and he thinks this means the streets should be full (well it's June 18, that's pretty close to the Summer Solstice, so when is sunrise there today? 3:35 AM and 22:24 PM. I'm not often one of them, but a lot of people are asleep at those times. Just this morning I took at taxi home at 5:30 AM, there weren't a lot of people on the streets then.) Same thing in Moscow. Edinburgh and Copenhagen in the 1840's. Dresden, Rio, Toronto, Athens, 1860's. Then street scenes with people from London and Paris.
The first photo, we are told was in 1822 (well 1826, close enough) and the art of photography uses juxtaposition, comparison and contrast but they're not in these early photos and I think he's trying to say that the contrast in the photos from Russia are that the cities are large enough to hold millions of residents (just an assertion) but only had half a million residents. Population data shows linear increase since 1764 and many of the building in the photo were older than the photos (you don't say!). Did the Russians build these buildings for people who didn't live here yet (we don't have any photos between 1764 and 1860, so we have no information as to the capacity of the cities over the span of a century).
Another contrast between the population and the environment. Leap of illogic to the impossibility of the architecture, no evidence of impossibility. During indoctrination in school we rarely see old photos of cities because when we marinate (did he say that? sounds like that and auto-caption thinks so, too) on those images and see promotive Victorian people looking tiny in comparison to the buildings we (if we are idiots) have doubts. Amount and weight of limestone in the Arc de Triomphe. How did they do it?
Don't settle for less
How do we do it How do we do it Volume! volume! Turn up the volume! - Tom Waits, "Step Right Up"
Photos of sculptures and the geometric patterns on the arch. And he's back to power tools again. He doesn't believe people can do things by hand. More features he couldn't do himself with a 3D printer let alone a chisel. More contemporary photos from Paris, some other grand structures and some less so as he thinks should be all that exists in a horse-and-cart civilization. A photo of the arch from 40 years after it was build "suggests" that it is much older because he knows how fast limestone weathers.
In late 19th century Moscow people are shown in a photo of "the infamous Red Square". More blather about how they couldn't have possibly built this, and why are the roads in bad shape if they had technology? The Crystal Palace of London predates automatic glass manufacture. Why did they spend more money on buildings than on mud-free roads?
OK, I'm going to skip more of the same argument with examples from other parts of the world.
We're up to Episode III, "Inheritors of Mud and Magnificence". Nope, I didn't record the previous section titles. OK, they were Volume I, "Buried in Plain Sight", Episode I, "Questioning His-Story", and Episode II, "A Lens into the Past"
2011 earthquake in New Zealand. Soil liquefaction occurred (yes, it did). Other examples. So his claim is the muddy roads (but no collapsed buildings as happened in his earthquake examples) are the result of similar earthquakes which no one recorded because reasons. Bu he's mot done, there are also windows close to the ground or partially below (why? to get light into the basement). He has no idea why someone would install a basement before there were power tools let alone use columns.
He claims there was a global event. Dickens opened "Bleak House" with a mention of mud in the streets, as if a flood had just ended (as if, if it actually happened why didn't he say so, and if it was suppressed by "them", why did "they" let him print that?). Photos of soil moving shows the soil or mud had only recently arrived and "they" are hiding the truf. Back to literature of the time, that is concerned with marriage female chastity and orphans and adoption. It seems that the orphans weren't actually orphaned, but separated from their mothers (no evidence) because they were born outside marriage. Lots of photos of orphanages. Lots of pics of orphans, real information about how they were mistreated, some photos of children working in factories.
And then amusement parks (wait, what was the point of all of that about orphans?) which used to have Infantoriums where premature babies were on display in incubators. Yeah that was a thing, it seems that they were funding infant care thru admission fees. But he's suspicious. Why would people pay to see babies? Maybe they'd never seen one before. And how could they have had the tech (glass? warmth? what's the problem here?) Did the US even have a large enough population to produce all those preemies? And Martin A. Couney who was involved with the Infantoriums seems not to have had a medical degree and a silent film star may have had a child die and/or adopted a baby through one of these amusement parks but it's not in her official biography.
So what was this all about? Repopulation. Chastity was justification for stealing children. The cities looked empty because no one lived there, and thirty years later they were populated by orphans who were sent to live in them. (I'm really confused, if you had empty cities, why not encourage families to move there instead of taking away children? And if you had a population shortage, why insist on chastity? If you can invent chastity out of thin air, do they opposite and convince women to have babies nonstop, married or not)
What does this have to do with FE, he asks, assures us it will make sense. He's been yammering for an hour, good thing YouTube will play it at 2X. Once again we don't have much time (only four hours left) and I have stuff to do, too, so I think I'll stop here. and pick it up later with Episode IV.
Update: why not watch some real physics lectures instead? Here's a series of lectures by Richard Feynman.
