We’ve probably all had a few conversations with people who hold eccentric scientific ideas, and most of the time they yield nothing more than frustration and perhaps a headache. In [Bertrand Selva]’s case, however, a conversation with a flat-earth believer yielded a device that uses a pair of gyroscopes to detect earth’s rotation, demonstrating that rotation exists without the bulkiness of a Foucalt pendulum.
[Bertrand] built his apparatus around a pair of BMI160 MEMS gyroscopes, which have a least significant bit for angular velocity corresponding to 0.0038 degrees per second, while the earth rotates at 0.00416 degrees per second. To extract such a small signal from all the noise in the measurements, the device makes measurements with the sensors in four different positions to detect and eliminate the bias of the sensors and the influence of the gravitational field. Before running a test, [Bertrand] oriented the sensors toward true north, then had a stepper motor cycle the sensors through the four positions, while a Raspberry Pi Pico records 128 measurements at each position. It might run the cycle as many as 200 times, with error tending to decrease as the number of cycles increases.
A Kalman filter processes the raw data and extracts the signal, which came within two percent of the true rotational velocity. [Bertrand] found that the accuracy was strongly dependent on how well the system was aligned to true north. Indeed, the alignment effect was so strong that he could use it as a compass.
In the end, the system didn’t convince [Bertrand]’s neighbor, but it’s an impressive demonstration nonetheless. This system is a bit simpler, but it’s also possible to measure the earth’s rotation using a PlayStation. For higher precision, check out how the standards organizations manage these measurements.
In the ’80s, I worked for a company that made a device for the military that used iron wheel gyros to do something similar.
There are plenty of video’s on youtube of teardowns of these old things…
A while ago I read an article about inertial navigation and US export regulations for “very good” gyroscopes. Apparently it’s quite easy to make a gyroscope that falls under these regulations by filtering / averaging the output of a whole bunch (100 or so) commonly available MEMS sensors.
Presenting evidence to a flat earther is pure masochism.
The mountain of evidence should be insurmountable, but stupidity knows no limits. If everything already available can’t convince them, nothing will. You could fly them to space themselves and they would claim you’re faking it. Engaging with their idiocy does nothing helpful.
I don’t think I’ve ever met a real one that wasn’t just trying to ragebait, however this figure looms large in the modern unconscious for some reason.
I, unfortunately, have met several real ones, in the part of my career that involves teaching apprentice/student engineers. Never a student, thankfully, but there is a message in that several of their parents (another level of WTF? These are supposed adults. I should never hear from their parents. Yet, over the last four decades….) and a former administrator of the school are the individuals. Also entirely too many vaccine deniers and evolution deniers (including students)
Engaging does nothing. Deflect. “I see. You certainly have made a point there”, from the same cloth as the classic “My! That certainly is a baby!” for the parent of an unattractive or unpleasant child.
The correct response in the last instance is “breathtaking”.
I’ve seen adults that actually believe there is some super being who created everything, and that there is an ‘afterlife’ as they call it.
And then there are those who believe politicians are some kind of special people who command special respect.
It’s funny how ALL kids eventually settle into some form of insanity as adults.
(Yes that means I too am a victim of various forms, as are all of us.)
It goes back to the point of how so many priests are actually atheists or agnostics.
It’s either that, or they try to start their own cults, or become TV-evangelists and scammers, or simply go mad, or give up and go fly a kite instead. Any organized religion becomes a system of practical heresy where, if you take the actual official point too seriously, you’re bound to get or cause trouble. Hence, the people who aren’t smart enough to see past the show rarely rise above the status of a village idiot.
What the hell are you even talking about– trashing people who believe in God because you don’t? I thought there were smart people here…
Who said I don’t?
We’re on very good terms: God keeps out of my hair as long as I don’t try to define God.
Being smart is one of the prerequisites for atheism.
Thinking you’re smart is one for belief in a god
Mother Teresa herself lost her faith or at least substantially doubted the existence of God for like 50 years. Just sayin’
The exceptions do not make the rule, you should know this.
Agreed, when I read “a conversation with a flat-earth believer”, I thought “well that is a waste of time”. “In the end, the system didn’t convince [Bertrand]’s neighbor”, oh wow, how shockingly unexpected.
The trouble here is that all this is happening in a “black box” that only the creator understands, and the neighbor doesn’t, so in their perspective they could be just saying stuff and performing magic tricks.
If the experiment isn’t well controlled, it can also return true results out of false premises, such as the Kalman filter amplifying noise in a way that happens to give a trend in the right direction. Just because an experiment agrees with something that is already supposed doesn’t mean the experiment proves the point.
Except the mountain of evidence includes plenty of practical experiments one can do that aren’t hard to understand. There’s a reason we figured out the earth was round before we discovered electricity, let alone gyroscopes. At a certain point it becomes willful ignorance, and I have yet to see a good way to counteract such.
A fervent believer in something patently false is either going to be a fool or a fraud. Fools cannot be helped, while frauds always have an angle to why they’re insisting on the false belief, and if you find that angle you might be able to expose them. That’s because they will be arguing out of bad faith: you’ll find a crack that shows they don’t believe in their own gospel after all.
The more difficult part will be to convince everyone else that his person is a fraud, because they too have their own motivations in believing them. In the end it’s not about what is being said at all – it’s about who is saying what against whom? If you’re trying to convince a cabal of believers that their stuff is nonsense, you’re fighting against an identity that justifies other behavior and attitudes, such as claims to ownership or power. It’s those other motives that demand the false belief in the first place.
“Presenting evidence to a flat earther is pure masochism.”
I haven’t paid attention to the “flat earth” garbage, so I don’t know and don’t care how they discount spacecraft in orbit, images from spacecraft, tides, night and day, the movement of the moon, etc., etc.
I also don’t know how the moon landing was faked crowd can make that claim. They don’t think the Soviets would have blown the whistle on that? They’ve obviously never watched the many NASA Apollo quarterly progress reports that showed the absolutely MASSIVE infrastructure being built in many places in the US just for that program or the film of the gigantic hardware being built and tested.
I think Buzz must have been in a bad mood on this day:
Buzz Aldrin Punches Conspiracy Theorist in the Face
On September 9, 2002, astronaut Buzz Aldrin—the second human to set foot on the moon—is walking outside a Beverly Hills hotel when a conspiracy theorist starts harassing him and accusing Aldrin of lying about the Apollo 11 moon landing. Incensed, Aldrin punches his heckler in the face.
https://www.youtube.com/watch?v=wCvhpxznQWo
There is a much easier way to convince flat earthers they are wrong.
Just tell them that if the earth was flat, cats would have pushed everything off the edges.
This is why, since ancient Egypt, we’ve known the earth isn’t flat.
Jokes aside, no one ever really believed it historically. It’s a modern invention.
The phrase “no one” tells me that that is not true.
Eh… where we have records of what people thought about the shape of the world they mostly don’t think it’s flat. However the descriptions of “the world” from Ancient Babylon do kind of describe it as flat, but also only extending to the mountains to the North, the desert to the South and the two seas East and West. Roughly a thousand kilometre diameter circle. They were also trading with people from across the seas, so presumably they knew they were only describing their world rather than everything in existence, perhaps they trusted their trading partners to describe their own worlds in their own ways.
I went down the flat earth rabbit hole years ago to see why flat earthers believe. First i watched a video where a group put a large target on the back of a boat, pointed a laser on shore at the target, and then drove the boat 5 miles out to sea. The dot was still in the middle of the target five miles out. Then I read about some greek guy who held a pole to the ground and measured the shadow cast by the pole. The next year on the same date and time but many miles away from the first reading he repeated the measurment and the shadow was longer. He declared the earth was round based on the measurments. I tried to repeat the experiment in my living room with a lamp attached to a table and a popsicle stick. The results showed a longer shadow the further I moved away from the lamp. clearly this means that the further north/south you go from the sun the longer the shadow will be. Then I watched several videos on refraction including one where if you place a matchbox car on a table and come slowly down to the surface of the table the wheels of the car will disappear. Yes I figured out how some can be deceived, but, it also left alot of questions in my mind. I’ll end this with i’m not a flat earther, but, always keep your mind open to the possibility that you can be wrong.
The laser on the boat example 1 was refraction. the laser curves because of the water. Same effect as the matchbox car.
Example 2 is Eratosthenes measurement. As said above if you move the stick further from the sun IE to a higher or lower latitude the shadow will be longer.
example 3 The grand canyon was not formed by years of erosion but rather was formed by continental upheavel and water went to the low spot.
/sarc
I have to pipe up, because I’ve (mostly) enjoyed some of the youtubers who try to correct the anti-scientific believers, Dave McKeegan’s and SciManDan’s videos are very good for example. Anyway, the wheels of the toy car don’t disappear because of refraction, they disappear because of the extremely out of focus table in the foreground.
“the laser curves because of the water.”
WAIT WHAT??? That’s simply not true.
Refraction happens with density differences. Between water and air, you always get some boundary layer where the air temperature and humidity is different, and light can be made to bend at such boundaries. It’s how mirages are formed.
But the real point about the laser on the target is this: the experiment only works if your laser pointer is tangential to the earth – if you set it perfectly level. If you point it slightly downwards, you will find that the dot keeps dropping down on the target as you move further away – as you would expect. But, then it starts rising up again as your boat follows the curvature of the earth.
If you shoot the laser beam from 6 feet high and pointing down, but not so low it hits the surface, you will find another point in the distance where the beam is also 6 feet high to the ground. In other words, you can easily fake the experiment to “show” that a curved earth is flat by rowing your boat out far enough that the laser pointer returns to its original height
So the laser doesn’t curve because of the water. QED.
It could be tangential to the earth, pointed slightly down or pointed slightly up. In all cases the dot will appear to move up on the target eventually.
Sorta. Dude more-or-less had it. It’s the refractive index gradient with altitude that matters: It’s the gradient that bends the light. A uniform, level surface of cold water promotes that gradient, along with the natural atmosphere density gradient with altitude.
Earth’s normal atmospheric refractive index gradient isn’t sufficient to bend light all the way around, but under inversion conditions where radiative cooling causes a strong temperature gradient, it could work over some area.
If you’re waiting for the dark still air at 4 am in the desert to do the experiment it just might work. A late summer afternoon on the Mediterranean? Nope.
I understand mirages at sea, ships and cities in the sky. Also in desert environments so I say again:
“The laser doesn’t curve because of the water.”
“Sorta. Dude more-or-less had it.”
“If you’re waiting for the dark still air at 4 am in the desert to do the experiment it just might work. A late summer afternoon on the Mediterranean? Nope.”
I’m gonna wait to see the data. Where does the evidence take us? I say when you say “If you’re waiting for the dark still air at 4 am in the desert to do the experiment it just might work. A late summer afternoon on the Mediterranean? Nope” you’re arguing by assertion. Data please. The experiment always works. Show data saying otherwise. Start with “Does the water stone cold chillin’ that the laser isn’t engaging with bend the light up or down?” No one’s addressed that in this argumentbyassertion Fest. Data please.
Negligence of data ne’er won the heart or mind of a Flat Earth believer. Weak as water, Captain Peacock, and I am unanimous in that.
The water is constantly evaporating, creating a temperature and humidity gradient, both of which contribute to the bending of light and the formation of mirages at certain viewing angles.
So yes, water is bending the light.
“So yes, water is bending the light.”
Unfortunately, water vapour acts in the wrong direction: Water vapour being less dense than air, a higher water vapour gradient tends to cancel the effect of the density gradient.
You really want cold and dry.
Contributions of atmospheric components to the speed of light was part of a thesis I wrote in 1986. Good enough to get me a degree, so someone thought it had merit. Sorry: It’s not online.
The actual version involved wells, not the shadows of sticks, although you could use the shadow of a stick as well.
A well points up, and you can show that with a bit of string and a stone, so if you observe the shadow cast by the sun at the bottom of a well in different locations on the same date, you’ll quickly notice that the “up” direction of the wells are not pointing the same way. The shadow does not fall as you would expect if the wells were on a flat plane pointing in the same direction.
If you’re doing it with a stick, you can find the angle at which the stick casts no shadow – it’s pointing at the sun. You then compare that to what is “up” using the string and the stone. Moving around will change the angle, but moving around on the surface of a sphere will change the angle more than you would expect.
Your result might vary if you’re high up a mountain or low in a valley and explain the difference that way, but with enough distance between locations your difference soon becomes greater than any mountain or valley.
The myth says the well was the inspiration for the experiment, but the experiment itself wasn’t performed with wells.
My favourite zero tech globe earth proof is to watch a sunset/rise from the top of a mountain. The shadow will go past the horizon onto the cloude above you. If your shadow is above you then the sun is below you which can only be true if the earth is round or the sun is underground.
I had a flat earther tell me straight faced that the shadow in the clouds was from the sun reflecting off the ground.
Or you’re high up a mountain and the sun is somewhere between the ground and you.
I just want to touch on one item here, you can not really compare a lamp with the sun, because the sun is very very far away with as a result that its rays are basically parallel from our distant location and to emulate that you need a simulation of that by creating a light source with parallel rays.
Mind you I think flat earthers claim the sun is not that far away right?
Disclaimer: I don’t say any of this to question the reality of the roundness of the planet (sigh)
Oh and I don’t believe this story of some flat earthers actually have a laser with such a powerful and well collimated laser that also manages to lock on a target on a boat on the sea at that distance , a sea which has waves I like to point out. I don’t think it’s refraction but just fakery. It’s very easy to fake a laserdot of course, you don’t need sora or anything.
2 years ago I met a flat earthier, he installed my fiber internet!!??!!(really)
GPS??? Him: Balloons.
Me: Ohhhhh Kayyy….kool beans.
Me: Walked away(quickly)
Shouldn’t the person installing the “fiber internet!!??!!(really)” be the one to walk away, or were you just a groupie?
“Me: Walked away(quickly)”
I learned a LONG time ago that you can “try” to educate the ignorant but
you can’t fix stupid.
You can vote it into office though.
And you don’t even need to take the flavour of stupid into account!
Next: suggest chemtrailers send sample collection flights up to contrails.