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https://www.bbc.co.uk/news/science-environment-64603521

FYI Luke Air Force base, as well as a statue in Phoenix, are dedicated to Frank Luke Jr. Frank was a daring WW1 ace, who shot down 14 German balloons and 4 aircraft during a short combat stint in France. Because balloon shoot downs were considered suicide missions,he was regarded by E Rickenbacker as "the most daring aviator and greatest fighter pilot of the entire war" The F-22 Rapto that downed the Chinese spy satellite used the call sign 'FRANK'

I find it interesting what the US military chooses to show to the general public, and what it chooses not to show. First, we have the incident with the Chinese spy balloon. The spy balloon got significant press coverage: it was tracked flying across the continental US, there was the big debate about whether to shoot it down or not, we had photos of the US Navy recovering it off the coast near Myrtle Beach, SC, the FBI assembling the evidence in a warehouse. You name it - we were shown it. It's been made into a big spectacle and all have been invited to come and see. Now, this Chinese spy balloon could just have easily been kept quiet and classified. There are numerous other incidents of surveillance by foreign adversaries that occur on a regular basis which are not publicized. Why was the public given such a show with this one? The result of all his sensational publicity is that a clear and vivid perception has been created in the minds of the American public about what it is the US Military shoots down when it comes to unknown objects. The idea that these objects are Chinese balloons, adversarial surveillance craft of some kind, has really been hammered home these last few days in terms of imagery, narratives, press coverage, etc. Attention, time, and energy in spades. There is now an anchoring point that the public can revert back to when confronted with future unknowns. Then we have the Alaska object. From what's been described it's markedly different in terms of its size, shape, appearance, and flight characteristics. The US gov also won't attribute it to any country, as they so quickly did with the Chinese balloon. In all of the press coverage I've read about the Alaska object, the Chinese spy balloon story is woven into the same article. I haven't seen a single article about the Alaska object that hasn't in some way referenced the Chinese spy balloon story. It's a tactic of misdirection, the old conjurer's trick - where the idea or perception that you want someone to conclude is the fact is linked, or connected, with an objectively unknown situation. Those without strong critical thinking skills will subconsciously link what you have referenced from the past as the factual explanation for the new unknown scenario. In this case the American public will conclude that the Alaska object is the same as the Chinese Spy balloon; they won't give it a second thought. Meanwhile, whatever was shot down over Alaska can be quietly collected with little publicity or fanfare. I suspect that any future reports of objects being shot down or unknown aerial objects in general will be linked with the Chinese spy balloon story also, since that narrative has been effectively anchored already.

One stated reason for the initial reluctance of the US Airforce to shoot down the Chinese balloon spotted over Montana was the risk of debris falling onto populated areas below. This wasn’t simply a matter of being concerned about the risk of heavy bits of metal or plastic landing on the heads of hill farmers. A more specific worry was that the object appeared to be dirigible to some degree, which raised the possibility that it might be equipped with reaction thrusters of some type, which in turn raised the possibility that there could be highly explosive and very dangerous hypergolic rocket fuels onboard. Photos indicated that the balloon clearly had outboard communications equipment and electronic scanners attached to its gondola, which in turn means that it must have had some sort of electrical power supply on board. Satellites and drones of this type don’t rely on Lithium ion batteries, (Lithium batteries function very poorly in low temperatures). It is much more common for long-range reconnaissance units of this type to be equipped with an RTG (Radioisotope Thermoelectric Generator) which uses thermal energy produced by the radioactive decay of Plutonium 238 to generate electricity via a thermocouple system. Shooting down a dirigible with a large lump of Plutonium in its PS probably didn't seem like a good idea to the USAF, so they waited until the balloon had cossed the Atlantic coast and was safely out to sea before bringing it down in a controlled manner into about 40 of water where the debris can easily be recovered by divers and reassembled for further examination. Rhetoric by MAGA extremists like Donald Trump jr. who was urging Montanans to shoot it down themselves (the ballon was well over 10 miles high) were deflated almost as rapidly as the balloon when a Pentagon spokesperson confirmed that 3 similar dirigible incursions had occurred during the Trump presidency, and that the POTUS had declined to authorise shooting them down. A humorous take by Vlogger Fran Blanche: https://www.youtube.com/watch?v=L2Z8-qxTQ-A

I think that maybe this could actually work, almost. Feel free to ask questions about this here, but for expediency, an explanation of the theoretical operation of this Maxwell's Demon can be found here: https://stirlingengineforum.com/viewtopic.php?f=1&t=5338&p=18503#p18503

@Saber Curvature of the Earth: ~ 16.7 km distance is just ~ 21 meters..

Yes, he will feel like going down slope to the center and then up slope again. This is because our vestibular system detects gravity as a direction down. It is not very different from your ball example.

@Saber Did you have trigonometry in school? Use Pythagoras' triangle to find out how curvature changes with distance: What you see here, 6 degrees, would be equivalent of ~ 670 km.

If they measure a shortest distance from one corner to another on the diagonal, they'll find that the line of the shortest distance goes along the surface, touching the surface all the way. Thus, the surface is flat, not slopped. Another way is by drawing a large triangle on the top surface and measuring its angles. If the surface is slopped inward, the sum of the angles will be less than 180o. If the sum is 180o, the surface is flat. They will find that it is in fact 180o. Not slopped.

Cyprus has one of the world's best exposed ophiolite sequences (uplifted oceanic crust), the Troodos Ophiolite.

The ball will behave like you describe, right. But the light rays will keep going straight and along the surface. So, if they just look at the structure, or make geometrical measurements, they will see that the top is flat. It would not be slopped toward the center.

I created flat ground plane with 1km x 1km size. Basically, you can't see the difference. The edge (the blue-gray transition, 1-2 pixels in the image) is 500m from the camera.

I added 100m x 100m x 100m box. Its center is 0.01 degrees away from us. 2*PI*6370000m / 360 / 100 = 1111.8m - 50m = 1061.8 m. Approximately 1km from the camera. Another view, but 0.1 degrees away from us.2*PI*6370000m / 360 / 10 = 11117.7m - 50m = 11067.7 m. Approximately 11km from the camera.

Yes, I presume each dot is a movement measurement and the colour shows how much, though not the direction. Here's a map that makes clearer what plates are involved and the plate boundary faults: The EAF is the East Anatolian Fault (the North one, NAF, can also be seen), where the earthquakes took place. The Arabian and African plates are pushing broadly North and the Anatolian plate is being squeezed between them and the Eurasian plate like a pip, sideways, to the West. I was interested to see a converging margin marked, which accounts for the curious catlike shape of Cyprus, with a "tail" pointing off to the North East, i.e. towards the earthquake fault. There seem to be some slight trenches in the sea bed around it. In the bottom centre of the map the DSFZ, the Dead Sea Fault Zone, can be seen extending Southward. This links up with the Gulf of Aqaba, the Red Sea and the African Rift Valley.

Half a cube. The southern hemisphere would still be a hemisphere.

Exactly. Level means equal gravitational potential. You should be able to use that information to answer your other questions.

In addition to the clarification studiot seeks, the size of this surface relative to the size of the planet is likely important.

Nice pictures. Can I respectfully suggest you do some thinking for yourself here. You should be quite capable of ansering these questions yourself. First just check up on the difference between a level surface and a flat surface.

The question of genetic predispositions towards personality traits, sociopathy, etc is another thread, right? Most people are not antisocial, and will assume duties of care presented as that society's ethos. Some have an "overachiever" personality trait and may extend their active care beyond what's required, other are "slackers," and will see if they can get away with some neglect (often with justifications along the lines of "I'm just one person, not much I can do" or "that's government's job.") To me, a classic contrast in the US attends the nuisance task of recycling. Some, if their city only has a few centers with dumpsters to take your recyclables to, will be happy to sort their stuff, pack it into the car, and haul it there. They feel good, doing something good for the larger community and environment. Others chuck everything in regular trash, can't be bothered, and say "the city needs to give us all curbside bins, period!" (often the same people who say, "clean air, pfft! I'll get a greener car when Big Auto makes one in my price range and my precise specs. I'll get a bike when they've got their own special pathways and the boss installs showers at work and allows casual dress and blah blah blah...") Some people do seem to have a larger sense of collective action and benefit than others. And this also relates to how much one buys into the way capitalism peddles "convenience" as a commodity. Americans are subjected to pernicious levels of this, as if having everything be as easy as possible were some ultimate virtue.

The point is that any heat pump requires an external energy input. It can be mechanical work, as provided by the motor in a domestic fridge, or it can be something else, say, electricity in the case of a Peltier device or something. But heat will not spontaneously flow against a temperature gradient. Energy input is required to make it do that. So if your device - regardless of what it is and how it is constructed - gets heat to flow against a temperature gradient to produce a hotter side and a colder side where there was none before, there has been an energy input somewhere. By the way, the reason you get attacked, by me and others, is blatantly obvious to anyone with a smidgeon of intelligence. You are obsessed with trying to overturn one of the best-established and best-validated principles in science and - in particular - dodging all the patient explanations that have been made as to why you can't do that. So stop playing the victim, when it is you that has chosen to wander about with a huge "KICK ME' sign strapped to your arse.

Distance to ground matters when taking pictures. Resolution is vastly superior at 100,000 feet up than it is at 2 miles up, for instance. Indeed. This, too. In truth, they’re still watching us right now today. Threads like this, what are people saying and speculating about. Which memes are rising to the top across social media platforms. What commentary is taking hold in chat rooms and engagement channels, which narratives are being pushed by influencers and aggregators. It really never ends.

Is there a source for that hypothesis , or is it a personal speculation? I suppose it is possible it was indeed a stunt, or test, to sow confusion and watch reactions, but that does not seem to account for China having a whole fleet of them, sent to all corners of the world.

Might this be the only time you've specified an event? Even if it's only an impending one?

Hey, count me in. @Lorentz Jr is doing the thankless job of trying to see what's inside the cuckoo clock. (1) You never specify events, or are very ambiguous about it. You keep referring to frame-dependent quantities as if they must mean something to a 'super-observer' that's only in your mind. (2) You never specify reference frames, or conflate different frames in one sentence. (3) You systematically ignore, or make no reference, to experimental results which, needless to say, totally confirm SR in each and every instance that's been looked into. In summary, you don't understand SR, nor are you willing to learn about it --or so it seems. It's impossible to follow your logic because there appears to none. None that's worth considering, anyway.

If Lincoln genuinely said that then the video is best forgotten. Now to horse to horse. @Boltzmannbrain I am going to offer you a wave explanation, though the principles that come out of it apply to any level, including quantum. So first what is a travelling wave ? A wave is described by an equation connecting time and space. In order to make this equation dimensionally corrrect (all terms in the same units) it must include a factor we call the velocity or speed. The basic equation is a differential equation which is satisfied by an infinity of ordinary equations , also called wave equations. All these equations must include the units factor I mentioned. These waves have certain charracteristics or requirements. Before a wave can travel it must be generated. Seems obvious, but the equations themselves do not tell us how this is achieved. The velocity of a wave is characteristic of the medium, not the wave. If a wave has material moving elements or particles the speed of these is not the same as the speed of the wave. In the light of 2 it is not suprising that a wave travels at different speed in different media. So let us consider a sound travelling through several media, air then a solid partition (say a pane of glass or sheet of wood), then back to air again. Very simple but it will do the job. In the air the sound wave is made by the particles alternately bunching together (thus increasing the pressure and density locally) and spreading apart (thus decreasing the pressure and density locally). Note that these air particles are free to move about. They are not linked to other particles directly by forces. When the wave arrives at the left hand partition surface this alternating pressure increase and decrease causes alternating displacements of the surface particles. Note these partition particles are connected to neighbouring particles by springlike forces as in my original diagrams. This pattern of alternating displacements is thus transmitted onwards through the partition to its right hand surface, where the reverse occurs and the motion is returned to the air the other side. Now these two modes of tranmission are fundamentally different by virtues of their different mechanisms. But there is only ever one sound wave in either medium. This process can be likened to handing on the baton in a relay, each runner operating in a manner appropriate to him or her. The baton is the wave energy. A travelling wave transmits energy and the mechanism of travel will, unsuprisingly, vary from medium to medium. So sound is not light, but they are both waves. The mechanisms are different but the above applies. That brings us to the level of mechanism you wish to study the phenomenon for light ?

Making clear that Xi may not have been aware of the flight also lays the ground for a later rapprochement, by offering him a ladder to climb down. He can fire a few military people and get back to the agenda. (I too was struck by the similarity to the Gary Powers affair.)

In 1979, Ayatollah Khomeini the new leader of the freshly installed Revolutionary government in Iran after the overthrow of the Shah ordered the Iranian airforce to shoot down US spy satellites orbiting in space over their territory. It apparently took some while to explain to the mullahs that this was not an achievable mission - no doubt Tom Cruise would have sorted it somehow ! CNN reports that in a Congressional briefing given on Thursday, US Intelligence sources identified the balloon as part of a fleet of surveillance devices built and operated by the PLA (Peoples Liberation Army) for military intelligence gathering purposes. The also said that Chinese Leader Xi Jin Ping may not have been fully briefed on the day-to-day operational details of the program, which helps to explain the puzzling anomaly of why China took such a risk right on the eve of an important visit by US Secretary of State Antony Blinken which was immediately cancelled because of the political fall-out. A precedent can be found in the Gary Powers U2 incident of May 1960 when a very important summit meeting between US president Eisenhower and the Soviet Leader Nikita Khruschev was abruptly cancelled after the U2 was shot down by a SAM. The USA claimed the plane was ‘a meterological research’ flight until the USSR produced the captured pilot Powers, and put the wreckage with its high power camera systems on public display. Intelligence gathering misssions of this type always involve a cost-benefit risk analysis. In 1960 the USA took the high risk of running the U2 overflight mission because they consdered it to be of paramount importance to have accurate information about Soviet missile sites and long range bomber bases ahead of the summit. They also believed that the U2 flew too high to be intercepted or shot down. It is not yet clear why the Chinese leaders regarded their ballon program to be of such importance.

Psychologists use experimental and mathematical techniques to more precisely quantify the relationships among the observable variables that are only passively observed by the layman, like personality traits for instance. If the development of a reliable and precise measurement tool isn't scientific, then what is? But the layman might not understand the math, and what is psychology separate of these mathematical techniques if there isn't any unifying psychological theory that unites the discipline of psychology? This can make it seem more like a massive data collection operation than a scientific endeavor. Or Behavioral Ecology bolstered by the occasional MRI data. Most measurement tools are trained on ordinary people whom the rater already can intuitively understand. Yet, the most extreme aberrations are the source of the most intrigue and the most worry, and they may have nothing to teach, especially if they're lying. Nature doesn't lie, nature isn't machiavellian. Many would probably fancy themselves to be the real psychologist in the room.

Okay here's a snapshot taken of the train car as it passes directly in front of a ground observer with an instantaneous camera. The red and green lines are continuous laser beams. The velocity is known to the ground observer to be 0.866 c because it was previously set up in the lab to move at that velocity in the lab frame. Length contraction has reduced the apparent length from 10 to 5 m, as the observer knows is predicted by SR, and the observer knows that time is slowed down to half the rate of his because the Lorentz factor for that velocity is 2 Through trigonometry, he knows that the diagonal line has gone from being 14.1421 m when the car was stationary to 11.1803399 m in the snapshot. Knowing that the speed of light in his world is 1 m/s, the ground observer knows that from his point of view a light beam traveling that distance would take 0.5 second but he knows that observers in the car must see it take 1 second of their time, because they see it travel 10 m instead of 5, the car being uncontracted in their frame. How does he make 0.5 second of his time look like 1 second in the car? He imagines a timer at the back wall of the car showing 0 and a timer at the front wall showing 0.75 second when the light beam is emitted from the back wall, so that by the time the beam reaches the front wall the timer will have progressed by 0.25 second in that frame, while 0.5 second has passed in his, and will then show 1 second. That would seem to reconcile things but he recalls that Einstein stated that clocks at the back of moving frames will be seen by a stationary observer to be ahead of ones at the front so he finds this perplexing, because he had to imagine the front clock being ahead of the back one instead. The ground observer then sees what would happen with the diagonal beam with that same timer desynchronization. It would take 1.11803399 seconds in his frame for the green laser to travel the path so, with the timers in the car running at half speed, it would take 2.23606798 seconds on their timers so, with the front timer being 0.25 second ahead of the back timer, the front timer would show 2.48606798 had passed but in the uncontracted car frame the distance would be 14.1421 m and should have taken 1.41412 second on their timers. Now the ground observer is wondering how Einstein was so wrong, apparently, because nothing at all turned out the way he stated that it should and, thus, he perceived that a conundrum was afoot and he needed some people on a physics forum to try to explain how that happened. I would never do such a thing as to smuggle anti-relativity sentiments into a physics forum, I'm offended that you would even think that. I am merely trying to resolve apparent conundrums, that's all.

Yeah that's real pretty, too bad you can't refute my last two diagrams credibly though. No idea what your diagram is supposed to depict, sure doesn't look like anything square or rectangular though. My diagrams are simple and logical, yours appear to be based on a severely distorted version of reality. By the way, I know that the vertical beam in my last diagram wouldn't be affected by the timer desynchronization but it still illustrates how Einstein made the mistake of thinking the actual light beams, or light pulse path, was stretched out just because the light clock was moving horizontally but how, if that were true, it would change the velocity of the light clock, same as I explained in the previous post. Do you seriously think it's scientifically acceptable to have velocity change dramatically just to shoehorn a theory into seeming to work in other respects? Either we know the velocity of the clock or we don't, which is it? What's the velocity of the clock. 0.866 c or 0.4641 c? I posted another thread a while back about the "light clock conundrum" and the only way anybody could explain how the Lorentz factor could be valid for the light clock diagram in that one was to do just that, suggest that the velocity was different than what it obviously was and therefore a completely different Lorentz factor was appropriate. Does Special Relativity contract velocity? I must have missed that part of Einstein's article, please quote the part about velocity contraction, or admit that there is an unresolvable conundrum.

I think you're probably the only person who didn't comprehend what I wrote, but I'll humor you. What do you say the velocity of the square and rectangle in the two diagrams were? If it's not 0.866 c or 0.4641 c then what is it? Are you going to make up some random velocity now?

Interesting that Genady considers disproving Special Relativity as trolling. I suppose if he can't actually refute my posts intelligently then throwing insults around is the next best thing. Same for Lorentz Jr. You fail to realize that the moving frame is not chasing its own light, it's exactly like it's not moving at all, you just think it has to chase its own light. It also doesn't matter if I do a two way version, I've done that on other forums actually. I'll see If I can find a diagram.

Do you have a credible refutation of my posts or is your position that SR is right so I have to make everything work to conform to it or I didn't do it right? It has never actually been proved that the one-way speed of light is constant in all frames as viewed from any other. How could it when nobody has ever measured the one-way speed of light in the history of mankind? Two-way speed of light can be the same while each of its one-way components are completely different, ie; 1 and 3, 2 and 2, 1.5 and 2.5, 1.25 and 2.75, I could go on all day. I could make a two-way diagram but it would be a lot more complicated and wouldn't help your case any, it would actually make it worse. Why don't you make a two-way diagram, Swansont, if you're so fond of the notion, or can't you make a diagram, just gripe about the ones made by others not being up to your standards?

I don't believe you or anyone in this forum is really interested in science, just repeating what anyone can read in wikipedia. I certainly understand SR and I certainly don't need to learn about it from people on a forum, I read the actual articles. But I suppose you can explain Einstein's theory better than him. Anyway, I'm obviously wasting my time here, so go back to rehashing wikipedia pages to people who haven't heard it exists, because I won't be posting here anymore, ever, none of you are worth the effort.

If we build a time machine, anyone may use it and cause the past or future to change. Even if we establish an institution for using it that checks for altering the past, we still have the problem of sensing the natural past from an altered past, because we can't know whether some John or Jane were born - if they aren't famous. So unintended changes may cause someone not to be born, but was born in the natural past.