|Comments for Sunday, May 12, 2019,
thru Saturday, May 18, 2019:
May 17, 2019 - On February 26, I borrowed from my local library an audio book collection of five science fiction short stories by Philip K. Dick. I listened to the first one, but didn't particularly enjoy it, so I set the book aside. Then, yesterday, finding myself in need of something to do, I finished listening to the rest. The collection is titled "A World of Talent and other stories."
As an audio book, it is just 4 hours and 12 minutes long. Here is how "Good Reads" describes the five short stories in the book:
In "Small Town" a man creates a perfect scale model of his own town, as a means of escaping his unbearable reality. In "Human Is" the wife of a scientist notices that her husband has returned from a scientific expedition a changed man, but she's not complaining. In "Foster, You're Dead" a father's unwillingness to participate in his country's preparations for a war that never happens, leads to unexpected consequences for his family. In "The Hanging Stranger" a man is unable to convince his fellow townspeople that something terribly wrong is happening to them all. Finally, in "A World of Talent", society's reactions against those who have unusual talents have pushed the situation to the brink of interplanetary war.I wish I had read those descriptions before listening to the stories. Basically, I spent my time trying to figure out what is going on. If I had been reading the book, I would probably have given up. But, for some reason, the fact that I didn't fully understand what was going on didn't cause me to stop listening. So, what I did was waste time, which was evidently what I had decided to do when I started listening. But, I finished it, so I'm logging it as completed.
This morning I received an email that read (partly) as follows:
I'm not sure why they "invites" me, but I can guess. It looks interesting, but I'll probably skip it. I don't have a doctorate, and I don't understand the "theme."
Meanwhile, the problem with the TVs turning off at my gym twice a day seems to have been resolved (after nearly two years). I assume someone followed the instruction sheet I gave them. But I haven't seen the supervisor or any of the staff members I had talked with about it. So, they are either hiding from me, or they have moved to other locations or other shifts. It's another of life's mysteries.
May 16, 2019 - Yesterday evening, I finished listening to the audio book version of "Over the Edge of the World: Magellan's Terrifying Circumnavigation of the Globe" by Lawrence Bergreen.
I didn't realized it while I was I listening to it, but it is an abridged version of the hardcover edition. Ordinarily, I do not listen to or read abridged editions. I want the whole book or nothing at all. So, now I have to wonder if I would have enjoyed the full book as much as I enjoyed the short version.
I'm not sure how I decided to listen to it. I think I was looking for something else on my library's web site and the audio version of "Over the Edge of the World" appeared as being available. And because it was relatively short, I decided to borrow it. However it came about, I'm glad I listened to it. It's a very interesting piece of history. I had an atlas of the world at hand as I listened, checking it to see if I could find places on the southeast coast of Argentina where Ferdinand Magellan, his five ships and 270 men explored in hopes of finding a way past South America and into the waters of Indonesia, unaware that the Pacific Ocean lay between those two locations. One of Magellan's ship captains mutinied at that point and took his ship back to Spain. Later, when the remaining four ships had made it to the other side of the Pacific, another captain left the fleet and tried to find a passage through Asia to get to the Atlantic. He sailed all the way to Japan without finding such a passage.
Magellan, of course, didn't make it past the Philippines. While he was generally a very sensible person, he also did some very stupid things, and starting a fight with a local warlord was one of them. He didn't survive. Close to 90 percent of the 270 men who began the voyage didn't make it all the way around the globe, although some simply decided to remain in the islands of the South Pacific.
I think what interested me most was the level of detail the book provided. It appears that more than one person was keeping a detailed diary during the whole time. When a single ship, the Vittoria, finally made it back to Spain, the ship's logs showed a missing day, which was also totally unexpected. It was another lesson about living on a spinning globe.
I learned something else from the experience. I'd been choosing science books, humor books, travel books technology books, plus mysteries and science fiction, but I hadn't been looking at history books. This morning, when I browsed though what my library has in their history collection, I marked 8 audio books as being interesting enough for me to borrow when they become available. There are probably a lot more, but I only went half way through the list, and I just chose what seemed at this moment to be the most interesting.
If I can ever get back on track with my research into the physics of radar guns, I may not have time to listen to any of them.
May 14, 2019 - This morning I awoke thinking about tuning forks and the #1 dumbest idea in physics: the idea that all motion is reciprocal. That idea is stated at the top of page 124 in The Complete Sermons of Ralph Waldo Emerson, Volume 3, and also frequently quoted from page 142 of the book Duration and Simultaneity by Henri Bergson. And of course, it was also stated repeatedly in the arguments I had on the sci.physics.relativity UseNet forum. When applied to tuning forks it means that there is no way to tell if the tuning fork is vibrating or if the tuning fork is motionless and the person observing and holding the tuning fork is vibrating. I can tell.
I also keep thinking I should write a paper about the screwball ideas people have about radar guns and tuning forks. Both subjects are incredibly simple when you understand what is happening, but mathematicians insist on complicating them to make arguments that are beyond absurd. I just need to find the right way to approach the subject.
Meanwhile, yesterday afternoon, to get my mind off of radar guns and tuning forks, I finished listening to the audio book version of the second Fox & O'Hare novel by Janet Evanovich and Lee Goldberg, The Chase.
It took me 3 days to get through the 9-hour, 7-minute audio book. While the novel was amusing and enjoyable, it also seemed to be a hodge-podge of multiple crimes and multiple solutions. It starts out being about recovering an historic artifact - the bronze head of a rooster, one of the 12 symbols of the zodiac, worth about 20 million dollars - that was stolen by French and British troops from the Chinese Imperial Garden outside of Peking in 1860. When that artifact is recovered at about the mid-point in the novel, the story turns to being about recovering 3 Rembrandt paintings (worth about 100 million dollars each) stolen from a Montreal museum around the time the stolen bronze rooster head was being recovered. So, in a way, it is like 2 novels in one.
Like The Heist, which I finished on May 8, a lot of the humor in the book comes from the sexual tension between handsome con man and thief, Nick Fox, and beautiful FBI agent and former Navy Seal, Katy O'Hare, as they are forced to work together to solve the crimes. I have the later 3 novels in the series, but I think there are other audio books I want to hear before those become a priority.
May 13, 2019 - I'm not sure of exactly how long it took me to write yesterday's comment. I know I worked on it for probably around 3 hours on Saturday and another 3 hours on Sunday. Some of that time was spent trying to figure out how to illustrate the different speeds at which different parts of a tuning fork move. But then I figured that no matter what kind of illustration I produced, it wouldn't change anyone's mind if they believe what Kevin Brown believes:
Incidentally, people sometimes mistakenly think that the tuning fork calibration works by putting the fork arms in motion at the calibration speed. It should be obvious that this is not correct, first because the arms of a tuning fork move at a range of speeds, positive and negative, on each cycle, second because the speed of motion differs along the length of the arms, and third because the maximum speed of the arms depends not just on the frequency but on the amplitude, which depends on how the tuning fork is struck. It would generate a specific maximum speed of arm movement only if struck with precisely the right force, and even then it would begin to dampen out immediately, so it would actually produce a continuously varying maximum speed, which would be different at different positions on the arm, and with different orientations. Hence the arms of a tuning fork obviously do not move at a consistent reference speed.This morning, an idea occurred to me. I wondered if there were any slow motion videos of tuning forks on the Net. I found many, but two are particularly good. The first video shows a tuning fork that is fixed to a table being hit by a wooden ball-shaped striker. The fork vibrates for about 4 minutes in slow motion, which is probably just a few seconds in real time. But you can clearly see that the ends of the tines move fastest, and the farther you go down to the base you look the slower the tine moves. In other words, the tines wave back and forth, but the ends move farther in the same amount of time the bottom of the tine moves a shorter distance. And speed is distance divided by time. Here's that video:
The second video is more of the same, except that this time the tuning fork is being held by the demonstrator, and he moves the tuning fork around so you can view the vibrations of the tines from different angles.
It should be clear to anyone viewing these videos that if you point a radar gun at at a vibrating tuning fork that is turned sideways to the gun, every part of the tuning fork tine is going to be moving at a different speed than every other part. Kevin Brown was right about that. But, Brown is clearly wrong in arguing that the tuning fork
would generate a specific maximum speed of arm movement only if struck with precisely the right force, and even then it would begin to dampen out immediately, so it would actually produce a continuously varying maximum speedBoth videos clearly show the tuning fork vibrates at a constant speed for a long period of time (the time needed to put the fork in front of a radar gun and keep it there until a reading is completed), and amplitude has nothing to do with anything. Here's a screen capture from the second video showing which parts move fast, medium and slow:
Basic radar guns just measure and display the fastest speed in the target area, which would be the speed of the tip when it is mid-way between swings. That has nothing to do with sound waves or waves of any kind. It is just about what happens to photons when they hit various parts of the tuning fork at different times, and how the photons returning to the gun oscillate at different frequencies depending upon what part of the tuning fork they came from. Period.
May 12, 2019 (B) - Last week I had almost decided to give up on trying to prove anything about how radar guns are calibrated by using tuning forks. Then, in my May 6 comment I mentioned the "Radar Guns and Tuning Forks" section of Kevin Brown's web site mathpages.com. Here's a quote from that section that I didn't mention in my May 6 comment:
It’s important to note that the tuning fork is not sending a signal of 30 GHz + 4480 Hz, as would be the case for a genuine speed detection for 50 mph. The arm of the tuning fork is never moving at 50 mph (not even close). The tuning fork is only modulating the incident signal (which merely serves as a carrier wave), and this modulation has a frequency of 4480 Hz, which is equal to the beat frequency that would result from a Doppler-shifted signal reflected off an object approaching at 50 mph. In effect, the tuning fork is tricking the radar gun into thinking there is an object approaching at 50 mph, when in fact the tuning fork is just inducing a fluctuation in the antenna and receiver at the frequency of the beat that would be produced by an object approaching at 50 mph.After reading the part I highlighted in red above for the 3rd or 4th time, I decided it cannot be correct. So, I set about trying to figure out how fast the tine (or arm or prong) of the tuning fork is moving when the radar gun shows it is moving at 50 mph.
I visited a web site that does some of the calculations and displays them this way:
As you can see, I entered the Radar Frequency of 30 GHz, the Tuning Fork Tone of 4480 Hz, and then clicked on "Calculate or Re-Calculate." The displayed result, as shown above, was 50.07 mph.
So, the question then becomes: How fast is the tine moving when it gives a tone of 4480 Hz (and why does anyone care about the tone)? There can be no doubt that the tine is moving. Plus, we know that 1 Hz means 1 cycle per second. But, a "cycle" is not a measurement of speed or distance. In fact, when converted to distance, a cycle becomes a "round trip." That means that if a tine moves 1 millimeter, a "cycle" is 2 millimeters. The tine moves 1 mm in one direction and 1 mm in the other direction in one second. Therefore the complete cycle and total distance the tine travels in one second is theoretically 2 mm.
But there's another problem: Obviously, the tine does not move at a constant speed as it vibrates back and forth. It must come to a stop at the end of each move, and it must then gain speed again as it moves in the opposite direction. It only travels at its maximum speed around half way between starting and stopping. And we know the radar gun measures the tine's maximum speed, not its average speed, which is probably around 25 mph. (The radar gun does multiple readings to make sure it has the correct maximum speed.)
Kevin Brown's article also addresses this situation by saying,
Hence the arms of a tuning fork obviously do not move at a consistent reference speed. Moreover, to produce a maximum arm speed of 50 mph at the relevant frequency of (say) 4480 Hz would require the arm to swing a distance of 78 mm, whereas a typical tuning fork of this size has a maximum arm displacement of only about 0.02 mm. So, the speed of the arms of a tuning fork is orders of magnitude less than the speed of a moving automobile. For all these reasons, it is obvious that tuning forks do not (and could not) test radar guns by producing a moving surface at the calibration speed.I don't know where he got the 0.02 mm figure from, but the key point I'm trying to make is that the tine is moving at 50 mph for only a tiny fraction of a second and for only a small portion of each vibration. At the beginning and mid-point of each vibration the tine isn't moving at all. Its speed would be measured as zero. That would seem to say that the mathematics have nothing to do with reality, it is just a way of calculating a correct answer without any need to know what is actually going on. The formula v=cfd/2f0 means velocity is the speed of light per second multiplied by the fork tone per second divided by 2 times the radar frequency per second. What does that have to do with reality?
I found a web site which calculates speed for a given time and distance, and I plugged in 2 millimeters distance (actually 0.2 centimeters) in 1/8960th of a second (actually 0.00008960 seconds), and I got 49.93 mph:
I'm no mathematician, so I could certainly have done something wrong. I'm assuming that the tip of a tine on a 50 mph tuning fork can move 1 full millimeter, and I'm guessing that if the tip has a top speed of 50 mph, its average speed is ½ of that.
Researching further, I found an article about calibrating radar guns using tuning forks that was published in the Journal of Research of the National Institute for Standards and Technology (NIST). The authors say,
The tuning forks used to calibrate DTR [Down The Road] radar are usually machined from a solid aluminum blank to provide an acoustic resonant frequency that gives a specific speed indication for a given f0 [radar frequency]. To calibrate the DTR radar, the tuning fork is struck and then placed in front of the transceiver. The vibrations of the tuning fork modulate the phase of a radar signal reflected from it. This modulation simulates the difference frequency that is determined by the radar processing unit from a Doppler shifted return from a moving vehicle. However, the tuning fork does not actually simulate a moving vehicle. This difference will be clarified with the following discussion.The "difference" that is "clarified" in the "following discussion" after the above paragraph in the article is mostly mathematical, so it is difficult for me to decipher, but it seems to say that the tuning fork does indeed "simulate a moving vehicle." And it does.
At one point in every vibration of a tine, the tine is moving toward the gun at 50 mph, and at another point in every vibration the tine is moving away from the gun at 50 mph. At all other points in every vibration, the tine is moving at a speed that is less than 50 mph. The gun measures all the other speeds, too, but it only displays the maximum speed, which is 50 mph. So, the tuning fork "simulates" a fast moving vehicle amid a mass of slower moving vehicles.
I translate the term "modulate the phase" to mean "alter the frequency", which means writing this: "The tuning fork imposes a phase modulation on the incident microwave signal" would have been more clear if it had been written as "The tuning fork causes a frequency change to the original microwave signal." That is also what a moving vehicle does when it is hit by the "microwave signal."
I can also see that, no matter how much I argue that a radar gun does simulate a moving vehicle, others can just quote the NIST as saying, "the tuning fork does not actually simulate a moving vehicle." And it won't do me any good to say that isn't true. The tuning fork does simulate a moving vehicle for the tiny fraction of a second when it the radar gun is measuring the tuning fork's top speed.
I keep thinking I need to put this all in a scientific paper. The paper would show the utter stupidity of viewing light (and radio signals) as waves when light (and radio signals) actually consist of photons.
When radio signals are viewed as waves, the radar gun is typically viewed as if it was emitting sound waves. The movement of the side of the tine on the tuning fork creates different sound waves when it compresses and decompresses the air next to the tine. So, you are shown sound waves that are far apart being emitted by the radar gun and sound waves that are close together being returned to the radar gun. If you view what is actually happening as consisting of radio waves, things are very different. The radar gun sends out radio waves of a specific frequency and the tuning fork returns waves of an incredibly wide range of frequencies. The tip of the fork is moving faster than the middle and bottom of the fork and every point in between, so the fork is returning waves of countless frequencies. In addition, the tip of the fork is virtually stationary at the start and midpoint of every vibration, and it only moves at its top speed at the midpoint between every swing. So, waves bouncing back from the tip of the tine also return at countless different frequencies. There is a vast difference between real sound waves from a tuning fork and imaginary returned electromagnetic "waves."
If you look at radar guns as emitting photons, things are vastly simpler. The gun emits a spray of billions of photons (all oscillating at a specific rate) toward the vibrating tuning fork, a tiny portion of which actually hit the fork. The photons that hit are absorbed by atoms in the fork and then new photons are emitted by those atoms. The new photons oscillate at different rates depending upon how fast the atom it hit was moving when hit. The speed of the moving atom is added to the oscillation rate of the photon. The gun selects the returned photons that are oscillating the fastest, verifies that there is more than just one such photon, and then converts the difference in the oscillation rates between the emitted photons and the fastest-oscillating returned photons to compute the maximum speed of vibrating tuning fork.
But how come no text book or manual or article (except mine) describes things that way?
May 12, 2019 (A) - This morning, someone posted a very interesting comment to the Astrophysics and Physics Facebook group. Here's the first part of it:
Oxford University researchers have discovered the densest element yet known to science.
|Comments for Sunday, May 5, 2019,
thru Saturday, May 11, 2019:
May 10, 2019 - I'm continuing to research radar guns and how tuning forks are used to check their calibration, but it is hard to find anything that states anything that is not ambiguous. What I did find was a"scientific paper" that says,
The velocity of a wave is proportional to its frequency. Doppler effect shows that both the velocity and the frequency depend on the reference frame. The higher the detected frequency is, the faster the wave travels toward the detector. One example is the radar gun used by the traffic police. The reflected radio wave travels faster than the emitted radio wave. This results in frequency difference between two waves. This difference is used to calculate the velocity of a vehicle.I think that's the first paper I've ever encountered which argues that the speed of light changes to c+v when the radio waves return from the target vehicle. And, if I'm not mistaken, the first sentence says that high-frequency waves (like visible light) travel faster than low-frequency waves (like radio waves). That certainly isn't true, either. Of course, the paper uses mathematics to prove its theory.
The paper was found on vixra.org by searching for papers with "radar gun" in the abstract. It was the only one I found. My paper about "Radar Guns and Einstein’s Theories" is the only paper that contains "radar guns" in the abstract. Before searching through vixra.org, I tried arxiv.org and didn't find any papers with either "radar gun" or "radar guns" in the abstract. When I tried Google scholar, however, I found 1,870 matches on "radar guns" and 5,610 matches on "radar gun." And there around 75,000 which have "tuning fork" somewhere in the paper. I'm going to browse the ones that look interesting to see if they have something of value to say.
Meanwhile, none of the TVs at my gym turned off all week while I was there. I think my instructions on how the fix the problem may have been followed. I'll have to see what happens next week to be sure.
May 9, 2019 - Yesterday evening, at about 6:20 p.m., I finished listening to the audio book version of "The Heist," the first book in a series of "Fox & O'Hare" novels by Janet Evanovich and Lee Goldberg:
I really enjoyed reading the first seven "Stephanie Plum" novels by Evanovich. I have another seven in paperback and hard covers on a book shelf in my front room, and more on my Kindle, but I didn't have and hadn't read any Fox & O'Hare novels. When all 5 of them suddenly became available in audio book form from my local library, I borrowed all 5. It took just two days to finish "The Heist," and it's the second-longest book in the series.
The central characters are beautiful Kate O'Hare, who is an FBI special agent, and handsome Nick Fox, who is a super-thief and con artist that O'Hare just arrested and got sentenced to 5 years in prison. The two are forced to work together when FBI headquarters orders O'Hare to work with Fox to recover a half-billion dollars stolen by an investment banker who has fled to a lush villa in Indonesia, which has no extradition agreement with the U.S. Since the FBI cannot touch the culprit legally, Fox and O'Hare have to con him into returning the money (actually they steal the money back). It's kind of a funny premise, and the book has a lot of humor and sexual tension between Fox and O'Hare. Plus it has pirates and a lot of travel information about Indonesia. While it certainly wasn't as good as any of the Stephanie Plum novels I've read, it was still enjoyable. The question now is: Should I listen to the second book in the series (which is also the longest at 9 hours and 7 minutes) or should I read the eighth book in the Stephanie Plum series? Or should I read something else?
Or should I work on resolving questions I have about radar guns, tuning forks and Einstein's Theory of Special Relativity? I dunno. I just do not understand why more people aren't asking the questions I'm asking. If it is because everyone else already knows the answers, why aren't documented experiments providing those answers readily available everywhere? It can't be because no one else in the world gives a damn. Or can it?
May 8, 2019 - Yesterday afternoon, at about 4:45 p.m., I finished listening to the audio book version of "Around the World in 50 Years: My Adventure to Every Country on Earth," by Albert Podell.
It was an extremely interesting book, and not at all what I expected. I think I was expecting a book where the author just describes walking around and seeing the sights in different countries and being amazed by their curious customs and unusual foods. But "Around the World in 50 Years" is far more of an adventure book. Albert Podell is a travel writer, and he had already visited all the "pleasant" tourist attractions, since he did that job for decades, before he decided to visit all the rest of the countries in the world. It actually took him over 50 years to make the 102 separate journeys, to travel nearly a million miles, to visit all 203 countries in the world (7 of which no longer exist). The book is mostly about going to the places where people who travel for fun would never go: central Africa, remote parts of Asia, and remote island nations in the South Pacific. According to Amazon's review:
He survived riots, revolutions, civil wars, trigger-happy child soldiers, voodoo priests, jihadists, robbers, corrupt cops, and Cape buffalo. He traveled through every kind of earthquake, cyclone, tsunami, volcanic eruption, snowstorm, and sandstorm that nature threw at him. He ate everything from old camel meat and African field rats to dung beetles and the brain of a live monkey. And he overcame encounters with crocodiles, hippos, anacondas, giant leeches, flying crabs―and several beautiful women who insisted that he stop this nonsense and marry them.A lot of the book involves travels to Islamic countries where civil wars have raged for decades, places like Chad, Mali, Niger, Ethiopia, Uganda, Nigeria, Ghana, and Yemen. In some countries, like Yemen, he had to cross the border illegally, since there was no way for an American tourist to get into the country legally. He didn't travel alone, however. He traveled with body guards and usually a few friends, including some beautiful female friends. Most of the time in Africa, he traveled via private vehicles, only using "public transportation" when traveling by air. Bribes were common nearly everywhere, and more than once he paid as much as $4,000 to bribe someone to let him enter some place where Americans were forbidden to go.
In Asia, he visited Burma (Myanmar), Mongolia, Nepal, Bhutan, Thailand, North Korea and Vietnam, among others. And he doesn't hide the fact that he visited some sex clubs in Bangkok where $150 paid for 2 hours of massages, bathing and sex with his choice from "60 lovely ladies, ages 18 to 28, [who] were seated on a three-tiered stage, all provocatively dressed, each with a big numbered button on her dress for identification."
In the South Pacific he visited countries like Brunei, East Timor, Kiribati, and the tiny island nation of Nauru, "a speck in the Pacific, 25 miles south of the Equator, little known and rarely visited, a sad story and a strange piece of work, the 185th nation on my quest.
"At 26 square miles, it is the third smallest nation, larger only than Monaco (0.7 square miles) and Vatican City (0.2 square miles). With fewer than 10,000 inhabitants, Nauru is ahead of only Vatican City (population 850), the smallest internationally recognized independent state by both area and inhabitants."What I got from the book is that a lot of the world is involved in civil wars and wars with neighboring countries. I thought I already knew that, but I clearly didn't realize just how many countries are very dangerous to visit, particularly those where Islamic extremists are numerous and active.
The last country he visited was Angola in southwest Africa, but then in 2014 he revisited Yemen and Equatorial Guiana legally just to make them official.
I listened to the audio version of the book over a period of 3 days. Since it is 13 hours long, that means I listened for an average of more than 4 hours per day.
After supper yesterday, I began listening to another audio book, a detective novel, which I half finished. Listening to audio books keeps me from thinking about radar guns, tuning forks and physics. Hopefully, I'll be viewing those subjects with a "fresh mind" when I get into them once again.
May 6, 2019 - While researching radar and lidar guns this morning, I found another quote from the same mathematician I quoted yesterday:
Incidentally, people sometimes mistakenly think that the tuning fork calibration works by putting the fork arms in motion at the calibration speed. It should be obvious that this is not correct, because the speed of the arms of a tuning fork depends not just on the frequency but on the amplitude, which depends on how hard we strike it. It would generate a specific speed of arm movement only if struck with precisely the right force, and even then it would begin to dampen out immediately, so it would actually produce a continuously varying maximum speed, making it not useful for calibration. Moreover, to produce an arm speed of 50 mph at the relevant frequency of (say) 4480 Hz would require the arm to swing a distance of 78 mm, whereas a typical tuning fork of this size has a maximum arm displacement of only about 0.02 mm. So, tuning forks do not test radar guns by producing a moving surface at the calibration speed. Needless to say, they also do not work by means of acoustic sound waves, since the radar receiver isn’t affected by acoustic waves. It just so happens that the Doppler shift for automobile speeds and radar waves is in the range of audible frequencies.A tuning fork vibrates at a given rate and produces a specific sound frequency, which is the purpose of a tuning fork. According to another source:
I'm going to have to do more research to make certain I understand how that works. Clearly it disagrees with the first quote.
Curious as to who the author of the first quote (and the quote I used yesterday) was, I accessed https://www.mathpages.com/ and found the author was someone named Kevin Brown, who has evidently self-published 16 books and a couple hundred "articles" about mathematics. However, there isn't any information at all on his web site about who Kevin Brown is. A Google search finds a site that says he is Dr. Kevin S. Brown who lives in Kent, Washington. But that is all it says. And it seems that other people have also been trying to find out more information about him. He seems to have spent a lot of time arguing on UseNet (and Google) science forums. So, I may actually have argued with him. He arguments are certainly virtually the same as the arguments some people on sci.physics.relativity have used.
Meanwhile, when I went to the gym this afternoon, nearly all of their TVs were working fine, and none did the automatic power saver shut off while I was there. One cable box seemed to be turned off, but I have no idea why. Is the problem with the power saver switch fixed? Time will tell. Did they use my instruction sheet to solve the problem? I may never find out.
May 5, 2019 - I think I'm slowly recovering from my trip to Virginia. Instead of thinking about things discussed while in Virginia, this morning I awoke thinking once again about radar guns ... and LIDAR guns. And I was also thinking about the quote I used on May 3:
Dijksterhuis’s work also shows that our unconscious thought processes don’t engage with a problem until we’ve clearly and consciously defined the problem. If we don’t have a particular intellectual goal in mind, Dijksterhuis writes, “unconscious thought does not occur.”I'm not sure if my conscious or unconscious mind came up with it, but I awoke this morning wondering about two things:
1. Can a radar gun send and receive signals at the same time?I think the answer to the both questions is "No." I recall reading that a radar gun sends a signal and then switches to receive mode to capture the return signal. And I recall reading that basic radar guns do not measure distances. LIDAR guns measure distances. Basic radar guns are "continuous wave" radar, which simply means that it is sending out radar photons for as long as you hold down the trigger. According to an on-line source:
As opposed to pulsed radar systems, continuous wave (CW) radar systems emit electromagnetic radiation at all times. Conventional CW radar cannot measure range [i.e., distance] because there is no basis for the measurement of the time delay. Recall that the basic radar system created pulses and used the time interval between transmission and reception to determine the target's range. If the energy is transmitted continuously then this will not be possible.That also seems to say it is sending and receiving at the same time. However, it could also mean that it is constantly switching between send and receive modes when you hold down the trigger. The key point is that you cannot measure distances that way. Using radar, you can only measure speed via the Doppler effect. The Doppler effect is measured by comparing the emitted photon "wavelength" to the returned photon "wavelength."
LIDAR doesn't compare wavelengths, it measures distances. Here's how one web site describes the way LIDAR guns work:
Lasers use light and we know the speed of light (roughly 186,000 miles per second). When we send a quick pulse of light out, it will travel from the lidar gun, to the target vehicle, and back. If we measure how much time it takes to get a reflection (time of flight), we can calculate how far the light had to travel. Because the laser beam had to make a round trip to the car and back, if we divide that number by two, we’ll get the distance between the lidar gun and the target vehicle. That’s step one.That same web page also says,
Laser guns typically take about 0.3 sec to get a lock on a vehicle and for an example laser gun that fires 200 pulses per second, this means it needs 60 return pulses to get a reading.That second quote is kind of misleading since it suggests that if the gun sends out 200 pulses and gets back only 60, there is no way to match the sent pulse to the received pulse. In reality, the gun sends out a pulse, waits for the pulse to return, then sends out another pulse, waits for that pulse to return, etc., 200 times per second. So, it knows that the pulse it got back was from the pulse it just emitted. If it doesn't get back a pulse in a specific amount of time, it tries again. Traveling at 186,000 miles per second, light can make thousands of round trips from a police LIDAR gun to a target a block away in one second.
Each round trip pulse measures the distance to the target. Knowing the time between pulses allows the gun to compute how far the target traveled between distance measurements, and thereby how fast the target was traveling.
One key argument I've had with mathematicians is about the Doppler effect. LIDAR guns do not use any Doppler effect. However, you can easily find a math-oriented web page that says LIDAR does use the Doppler effect.
There seems to be a widespread misconception (in some venues) that LIDAR speed guns do not use the Doppler effect to measure speed. This may be traced to a popular online source, which gives the following ‘explanation’ for how a LIDAR speed gun measures speed, contrasting it with how a radar gun measures speed:
This ‘explanation’ actually highlights two misconceptions. First, it is obviously wrong to suggest that LIDAR speed guns don’t rely on the Doppler effect to determine speeds.The page then sets about using math to prove that LIDAR does use the Doppler effect. Actually, it only proves that you can use math to prove whatever you want to prove. If you have a basic misunderstanding about something, you can still develop mathematical equations to confirm what you believe. That is what mathematicians did when they believed that the Sun and stars orbited around the Earth.
To add to the confusion, weather radars are commonly called "Doppler radars," but they do not use the Doppler effect. Weather radars measure the distance and direction to a rain drop. It should also be obvious that they cannot track a specific rain drop, especially since the rain drop is falling downward and the weather radar tracks lateral movement of weather systems. What weather radars do is take a "snapshot" of the current location of countless raindrops in the area, then it takes another " snapshot" a few minutes later, and then another, and then they put the "snapshots" together to create a time-lapse movie so we can see how the weather moves. There is no "Doppler effect" involved.
I think the physics of LIDAR versus radar can be used to solidly disprove some common screwball beliefs held by mathematicians. But, mathematicians will never believe the proof, since they will just develop a mathematical equation that proves whatever they want to prove. Generally speaking, math cannot be used to confirm theories. Observations and experiments confirm theories. Math is just a tool that is used to help figure out what kind of observations and experiments to perform. If the experiment doesn't work, then either the theory or the math is wrong - or the experiment was improperly constructed - or all three.
|Comments for Wednesday, May 1,
2019, thru Saturday, May 4, 2019:
May 4, 2019 - I recall the greeting "May the Force be with you" from the 1977 movie Star Wars, but I think I heard the term "May the 4th be with you" for the first time a couple days ago.
According to Wikipedia, however, the term has been used for at least 40 years.
Apocryphally, the reference was first used on May 4, 1979, the day Margaret Thatcher took office as Prime Minister of the United Kingdom. An online news article from the Danish public broadcaster says her political party, the Conservatives, placed a congratulatory advertisement in The London Evening News, saying "May the Fourth Be with You, Maggie. Congratulations."When I looked for an image to display with this comment, I found hundreds of them on the Internet. I do not want to be out of step with the times, so ...
May 3, 2019 - As I was driving home from the gym yesterday, I heard this from the audio book I'm currently listening to on my car's CD player:
As most of us know from experience, if we concentrate too intensively on a tough problem, we can get stuck in a mental rut. Our thinking narrows, and we struggle vainly to come up with new ideas. But if we let the problem sit unattended for a time—if we “sleep on it”—we often return to it with a fresh perspective and a burst of creativity. Research by Ap Dijksterhuis, a Dutch psychologist who heads the Unconscious Lab at Radboud University in Nijmegen, indicates that such breaks in our attention give our unconscious mind time to grapple with a problem, bringing to bear information and cognitive processes unavailable to conscious deliberation. We usually make better decisions, his experiments reveal, if we shift our attention away from a difficult mental challenge for a time. But Dijksterhuis’s work also shows that our unconscious thought processes don’t engage with a problem until we’ve clearly and consciously defined the problem. If we don’t have a particular intellectual goal in mind, Dijksterhuis writes, “unconscious thought does not occur.”The book is "The Shallows: What the Internet is doing to our brains," and I'm currently on CD #7 in the 12-CD set. The above quote says what I've said many times on this web site. I go to bed thinking about a problem, while I'm asleep my "unconscious" (or "subconscious") continues to work on the problem, and when I wake up it sometimes presents a solution to me.
Unfortunately, right now I'm thinking about too many different problems, most of which would probably be of absolutely no interest to the people who read this web site. For example, for the past two years, four of the seven TVs on the wall in front of the treadmills and Exercycles in the "Cardio Room" have been automatically turning off at about 1 a.m. and 1 p.m. to save power, apparently because no one who works for the gym knows how to solve the problem.
In the image above, taken in January 2018, you can see 6 of the wall TVs and that 3 of them are off. There is one more that is off but out of view to the right. The 6 TVs hanging from the ceiling use the same cable boxes, except for one, which I think uses an 8th cable box.
The TVs turn off at about 1 a.m. and 1 p.m. because the cable boxes for those four TVs have their "power saver" options turned to "ON." That means that if the cable box has been turned on for 12 hours and no one has changed channels or anything else, the cable box assumes that everyone has gone to bed and it turns itself off in order to save power.
I've tried explaining to them many times that all they need to do is set the "power saver" timer in the cable boxes for those four TVs to "off." But it is like talking to a wall. They just do not seem able to understand. Or their brains are set to ignore suggestions from members.
Early last week, before I went on my trip, the shift supervisor even told me that it is impossible to use the remote control on one cable box at a time. He claimed tht, when they turn the TVs off and on, they must press the on-off buttons on the boxes, they do not use any remote control. I can make no sense of that, since the remotes work with light, not radio signals. And you can control where the light is pointed. Plus, I've seen the channels changed on the TVs. But I saw no point in arguing further.
Then, a couple days ago, on May 1, the four TVs again turned off at about 1:10 p.m. But this time it was different. When the gym staff tuned them back on, the four TVs all showed the same channel: It was Spectrum Channel 1, a local news channel set up by Spectrum. I recalled that when I had turned on my TV at home that morning, it had also been on Spectrum Channel 1. Evidently, Spectrum had changed things that morning so that when a cable box is turned on, it doesn't show the same channel that was being used when the box was turned off, it shows Spectrum Channel 1.
I explained the situation to the people at the gym. It means that when they turn off all the TVs and cable boxes when they shut down the entire gym on Sunday nights from about 5 p.m. to 1 a..m. Monday morning, ALL of their TVs will show Channel 1 when turned back on. The guy I talked with looked stunned, like it was an unsolvable problem for them.
When I got home it occurred to me that Spectrum must have a switch in their cable boxes to control what station you get when you turn the cable box on. And, yes they do. I don't know if it is new or if it has always been there, but I set the switch in my cable box to Channel 1351 (CNN Headline News) and, sure enough, when I turned my TV on the next morning, it was set to Channel 1351.
So, I prepared the instruction sheet below to show the people at the gym how to fix both problems:
I printed out 2 copies and took them with me to the gym yesterday afternoon. After I had swiped my card and checked in at the reception desk, I went into the Cardio room to see if the 4 TVs were still set to Channel 1. Two were, the other two were turned off.
None of the bosses seemed to be there, so I gave a copy of the instruction sheet to the guy tending the reception desk. No bosses showed up while I was doing my workout, and when I left I gave the second instruction sheet to the same guy. He seemed very interested and rushed off somewhere with it. I just left.
So, this afternoon I'll see if they just threw the instructions in the wastebasket, or if they still believe they cannot use their remote control on one cable box at a time, or if they are in the process of fixing the problems.
I guess the point in explaining all this is because it seems so much like the problems I have with mathematicians. The people at the gym seem to have closed minds, and nothing I say can change their minds. The same with the mathematicians. The only difference is that the people at the gym now have a very serious problem that clearly needs to be fixed. If they do not fix it, all seven TVs on the front wall and the 6 others hanging from the ceiling in the middle of the cardio room will all be set to Channel 1 forever. I do not think they'll let that happen. If they do not use my instruction sheet, they'll have to contact Spectrum or someone else to fix the problem.
I just wish there was such a crisis on the subject of how radar guns work. That way we'd all see who is right and who is wrong.
ADDED NOTE: When I got to the gym this afternoon, all the TVs were working fine and showed their normal TV channels. None showed Channel 1. However,
the only employee in the place seemed to be a young Asian woman behind the check-in counter, someone I've never talked with before. So, I have no idea if they used my instructions to fix the problem, or if they just called in some expert from Spectrum or from their head office. Did they fix the power-saver problem, too? I dunno. Time will tell. If the fixer did his fixing at 9 a.m. this morning and turned the TVs off and on at that time, the power-saver option won't turn the TVs off until 9 p.m. this evening.
May 1, 2019 - I'm still adapting to being home again after my trip. When I awoke this morning I briefly thought I was still in Virginia. The same thing happened last night while I was watching TV.
While in Virginia, in one of the quiet moments while not rushing around, I mentioned listening to podcasts, and learned that my sister had basically never heard of them. So, we listened to a few. Then I learned about Sudoku puzzles from her. They are something I had never heard of before (that I can recall). Here's an example.
Basically, the objective is to fill the above 9×9 grid with digits so that each column, each row, and each of the nine 3×3 subgrids that compose the grid (also called "boxes", "blocks", or "regions") contain all of the digits from 1 to 9. Like the example above, each puzzle already contains some of the numbers filled in. Here's the fully solved version of the puzzle above:
I wondered if it is a "logic puzzle" or a "visual puzzle." It appears to be both. I was amazed at how popular they are. And there are dozens of other number games and several different versions of Sudoku. All the games have Japanese names, so they evidently all originated in Japan.
Coincidentally, while I was driving around yesterday doing chores, I was listening to an audio book titled "The Shallows: What the Internet is doing to our brains," and I heard this passage:
In 2001, young Japanese women began composing stories on their mobile phones, as strings of text messages, and uploading them to a Web site, Maho no i-rando, where other people read and commented on them. The stories expanded into serialized “cell phone novels,” and their popularity grew. Some of the novels found millions of readers online. Publishers took notice, and began to bring out the novels as printed books. By the end of the decade, cell phone novels had come to dominate the country’s best-seller lists. The three top-selling Japanese novels in 2007 were all originally written on mobile phones.That is something I cannot even visualize. Long ago, I lived in Japan for a couple years, and I learned to read, write and speak the language a bit. I just cannot imagine cell phone texting in a language that has three alphabets, much less writing a book that way. Japanese has a 48-character alphabet for foreign words (katakana), a 46-character alphabet for Japanese words (hiragana) and they use Chinese characters for names and places. The Chinese "alphabet" consists of thousands of characters. How can you write them on a cell phone? Below is the only image I could find that shows Japanese text on a cell phone.
Maybe some day I'll find the time to research it and learn out how it is done. But, before doing that I need to do a million other things, and researching radar guns is still at the top of the list.
Hmm. I just received an email from someone who said that he can no longer access my web site. When he tries, he gets this message:
Clearly, it is a problem at his end. He appears to be using a computer connection that is public or semi-public and somehow their Sophos security software thinks my site has something to do with alcohol and tobacco.
Also, even though Google sent me an email two months ago which seemed to say they were going to shut down my two blogs, Debating the Anthrax Attacks and My Thoughts on the Changing World, on April 1, the blogs are still working fine.
Life is just one endless series of puzzles.