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Excellent analogy. And the underlying physics isn't so far off.

Not quite as direclty. The reason is that if your dynamics includes 3rd/4th order derivatives, you grind your teeth, increase step resolution, and get results. But higher order derivatives in differential equations make any numerical method cry. So even if you come up with a model that has fifth and higher derivatives, it will probably be useless for anything practical. But they do come up. Perturbation theory is probably the cleanest example. Both quantum and classical. And if we look at it in a more abstract way, just as whether there is use of higher derivatives, then sure. I've had to work with functions that involved sums of infinitely many orders of derivatives. (Which, thankfully, simplified.) And I've even came across some applications for fractional derivatives while trying to extend certain integer methods solutions to real numbers.

You just need sufficiently curved space between you and everything else. Which is possible in theory. That's how Alcubierre Warp Drive works. The problem is that there no known configurations that don't require negative energy, which is hard to come by.

In General Relativity, speed of light is a strictly local limit. Two "proximate" things can't travel faster than light relative to each other. (There is a way to put it into precise mathematical terms.) It's not a violation for two "sufficiently" distant objects to move at faster than light speeds relative to each other. But it indicates that space-time between two objects is not your basic flat space-time.

A clock in high orbit runs faster than a clock on Earth. A clock in low orbit actually runs slower, and there is an orbit where clock runs at the same rate as on the surface. Because there is time dilation due to orbital velocity as well. But yeah, GPS satellites actually have to take gravitational time dilation into account to get the kind of precision they gives you.

Not even close to how expansion of the universe works. a) Universe actually expands faster than light. It's accelerating. c) The UNIVERSE is expanding. Not just stuff being thrown out into the universe. There isn't an outside, or beyond, or anything of the sort. All points in space were once the same point at the moment of big bang.

Lets start with simple ones. Earth isn't massive enough to have significant effect. Neither is the Sun. So if we're measuring age of the universe from anywhere in the Solar system, we're going to be well within the error of measurement. If you are sitting on a surface of a Neutron Star and having a chat with somebody far away, communication will appear to be coming in at a faster rate. As if someone is playing the recording too fast. And yes, that means high pitched voices, faster moving clocks, the whole deal. And vice versa, to them, it will appear that you're slow. Now, for whether the observer on the Neutron Star will observe Universe to have the same age. The key question is when? Simultaneity isn't an obvious thing when you talk about time dilation. If you are talking to that observer, then he sees the same Universe that you do. Now, it does appear to him to evolve much faster, so if he doesn't take that into account, he'll say the Universe is much younger. But he'd also have no trouble actually making a correction for it, and arrive at the same number we do. Lets put it this way, we cannot have seen light from anything as it was crossing the event horizon. That light hasn't reached us yet. Nor will it ever. On the other hand, we can, at least in theory, see Hawking Radiation from a black hole. So we can actually see it. When QM mixes with GR, things get weird.

This thing seems to move due to "leakage". I'm talking about the waves that escape "resonator". If EMDrive simply got propulsion from RF leaks, it'd have power/thrust efficiency of a photon drive. We wouldn't be having a discussion then. Instead, it has a measured efficiency an order of magnitude better. Which requires reaction mass. Without reaction mass, demonstrated efficiency violates conservation laws.

It really depends on level of abstraction. If you are looking at an array as a single unit, I can see why it makes sense to think of it as uptime, rather than backup. I still think of each individual hard drive as a unit of storage. From my perspective, if I lose a drive, I have a backup on corresponding parity. Although, the fact that you can actually keep using RAID 5 with a drive down is all sorts of nifty. Makes me wonder why more intricate error-correction schemes aren't more common. I could even think of some RAID-like setups that would be ransomware-resistant. Having some breadcrumbs remain from plain text can do wonders in aiding an attack on a cipher.

Surely, that's context dependent. If the only kind of failure I want to safeguard against is mechanical drive failure, which is usually the only one that's entirely out of my hands as a user, then RAID is just as good as the first backup layer. Not that having something like a weekly off-site backup isn't a good idea to have on top of that, even for a personal machine. Fortunately, there are now cloud services that make it really easy.

Correct. And yes, DM being a new type of field/particle would make SM incomplete. Which is by no means impossible, nor would it really flip our understanding of physics upside down. SM is kind of built in a way that makes it relatively easy to add new fields to it without breaking everything else. The real problem is that we haven't detected that field yet. Which would suggest very weak interactions with known fields. And that makes it extremely unlikely that EMDrive can interact with it.

Not with RSA encryption. These keys are specifically designed so that you cannot reverse engineer a decryption key from an encryption key, and the malware comes with encryption key only. Otherwise, yes, the actual code to decrypt is identical to encryption code. You just need to know the key.

Not really. There are competing theories to explain dark matter. The two main categories are Weakly Interacting Massive Particles (WIMPs) and Massive Compact Halo Objects (MACHOs). (Yes, physicists are very silly people.) Only the WIMP hypothesis is consistent with a massive aether. And even then, there is no guarantee that it's evenly distributed. Fact that we've found no evidence of it in the Solar System suggests that it's probably not. In which case, it can't be responsible for propulsion. I suppose, there is possibility that density of it around here just happens to be much, much lower than in the rest of the galaxy. But would it then still be possible to get any measurable thrust out of it? The situation dark energy is even murkier. (Har! *cough* Sorry.) Suffice it to say, there is no reason to believe that it actually has rest mass. So even if we could somehow use it for propulsion, it's unlikely to actually have higher efficiency than a photon drive. Long story short, this is all very far from, "already know." It's one of the possibilities. It's on the table for hypothetical high efficiency propellant-less (but not reaction-less) space propulsion. EMDrive turning out to be such a device would make it the unlikeliest discovery yet. But I can't call it impossible. What I can say is that there are still a long list of far more likely explanations we're yet to cross out. And it will be far more time-efficient to test these first. Given the unexpected outcome of some previous tests, I think it's time to bite the bullet and do an honest ion trail search. If we can reliably exclude ion propulsion, EMDrive would rightfully step up from "curious" to "interesting".

Not with photovoltaics. These have a limited range of usable frequencies. On the low end, PVs are limited by thermodynamics. You can't convert into electricity EM radiation corresponding to energies bellow temperature of the cell. At typical 300K we have here on Earth, that means nothing with wavelengths over 5 microns or so. That's well into IR, so radio is a no go under normal conditions, You might be able to get to microwaves with sufficient cooling, though. On the high end, there is no strict limit, but you will start damaging the cell once you get to high enough energy. I don't know if converting gamma rays to electricity with PV is a way to go. In principle, though, of course you can convert other EM ranges into electricity. Radio antenna converts radio waves into electricity. It's not a lot of electricity, so it still has to go through amplifier in the receiver, but nonetheless, that is precisely what it does.

Which proves that there is a reaction mass involved. It's the only way to prevent situation where arbitrary amount of energy can, at least in theory, be created. Yes. An electric motor with a propeller is a perfectly good propellant-less drive if you are flying in an atmosphere. But it's only efficient up to certain speeds. Then you start having to waste a lot of extra energy. If there is an aether used by EMDrive as a reaction mass, I would expect a very similar behavior. There are, however, some caveats here that make it unlikely. First, aether cannot have sufficient EM cross section for EMDrive to grab onto it directly. Such aether would be very obvious in other experiments. We would have found it two hundred years ago, at least. Especially, since people have been actively looking. This still leaves an outside margin of probability that EMDrive does have some sort of a Q Thruster type of interaction with some exotic virtual particle, which in turn passes momentum to aether. This still raises a lot of questions, however. First, why haven't we seen this in particle accelerators, where we use far more powerful resonant chambers to accelerate particles? This ought to have been detected. Second, if this aether is weakly interacting, it can't possibly be "sticking" to Earth's surface. So we ought to be able to detect thrust variations depending on a) Orientation of the EMDrive, Orientation of Earth (time of day), and potentially c) Time of year. I haven't seen anything in orientation of EMDrive tests that screams aether, but they are noisy. It'd be nice to set up a series of tests specifically to exclude this possibility. It's still a very unlikely one, but not on the same margin of impossible as some other suggestions. P.S. Existence of weakly interacting massive aether would help explain some things, though. I just find it very unlikely that EMDrive can interact with such a thing.

Still not really a "plop", because gravity isn't linear. The event horizons do get distorted as the two black holes approach each other. Though, I honestly don't know if event horizons merge, or if a new horizon forms that encloses the two original ones.

Accidentally stumbling on a device where thrust is produced, while having something totally illogical for an explanation is not being right by any measure. It's being lucky, at best. Nah. Photon drive works just like a chemical rocket. With a chemical rocket, you have to have much higher thrust early on, because you have to push all these heavy fuel tanks. So you are burning extra fuel to accelerate fuel. Once you are going fast, you are using part of the kinetic energy of the fuel to help push your ship. So while you do get more power out of your engines than chemical energy of fuel ought to provide, that energy isn't free. You had to pay for it up front. Photon drive is much the same, except relativity is involved. If you have some supply of energy E, then once you got up to speed v, your total energy supply is actually γE, where γ = 1/sqrt(1-v²/c²) is the Lorentz boost factor. This extra energy is what lets you run photon drive at higher power (from perspective of "stationary" observer). But again, it wasn't free. Energy, in quantities you need to operate a photon drive, is extra mass. And your photon drive had to work extra hard to get that m = E/c² up to speed. There is some additional relativistic weirdness going on. If from ship's perspective, we maintain constant thrust, we maintain constant proper acceleration. Say, exactly 1g for convenience. (Yes, big photon drive.) From perspective of stationary observer, however, our acceleration is merely g/γ³. A stationary observer would conclude that this decrease in acceleration is due to two factors. Ship's mass has increased by a factor γ, because relativistic mass works that way, but also ship's drive appears to operate at lower thrust due to red shift and/or time dilation, depending on your perspective. It's important to note that while yeah, relativity does, in fact allow for thrust to decrease at extreme relativistic speeds, simply adding a constraint that energy is neither created nor destroyed, allows us to derive energy usage of such a drive. And it's still 300MW/N. In other words, the only thing that can operate that way is some variation on photon drive.

If it's interacting with something, I have no problems with it. I still insist that it's rather unlikely that it's interacting with something we haven't discovered yet, so we should be looking for conventional exhaust. But interaction with absolutely anything massive is fine in principle. The original proposal, however, besides all other nonsense, suggested that propulsion is entirely reaction and interaction free. It suggests that radiation pressure inside the chamber is responsible for thrust. Which is just as absurd as thinking that you can design a barrel of just the right shape, so that you can inflate it with some gas, and have it fly off without expelling any of that gas, purely on an imbalance of forces from internal pressure. The whole thing is made worse by the fact that the entire notion arises from failure to understand basic EM equations. So while I can see EMDrive working in principle due to an interaction with some sort of a medium, one thing we can pretty much guarantee is that it doesn't work the way its inventor said it should. For starters, you can't violate conservation of momentum without violating conservation of energy. They are the same law. But in practical terms, it's also very easy to generate as much energy as you like. Attach a couple of these EMDrives to the ends of a rotor, which is attached to an electrical generator. If it's a reaction free drive, it will require same amount of energy to generate same amount of thrust at any speed. (Otherwise, speed relative to what?) And power generated by a generator is proportional to speed and torque applied. Torque is fixed, because that's determined by size of the rotor and thrust. So in order to get more energy, we just need to have the generator turn faster. No matter how much energy EMDrive takes, I can have generator spin faster and still produce more power. In fact, as much power as I like, within mechanical capabilities of the generator. Infinite power. QED. If it takes a fixed amount of energy to generate thrust, either the amount of thrust must drop with speed, which happens if you are driving a car (speed relative to ground) or flying a plane (speed relative to air). Or you must have additional source of energy. This is a case with a rocket (extra energy comes from K.E. of exhaust.) But a reaction-free, exhaust-free drive cannot have either. No matter how it works, we can exploit it for free energy. So according to original proposal, not only would we be able to have flying cars with EMDrives that consume power comparable to a Tesla, but it'd generate its own power while doing so, and you'd never have to charge it. Which sounds awesome on paper, but there are some very good reasons why it simply can't work that way. On top of the proposal itself being, frankly, just stupid.

Well, seeing how not only does it violate conservation laws and allows for generation of infinite energy, but the entire model was derived from misunderstanding classical EM wave guide equations, the fact that his predictions are inaccurate is the one thing we do know with absolute certainty. Otherwise wouldn't even be the plain old unicorns improbable that the reaction-free drive would be. We'd be on the scale of, "This guy makes stuff up, and universe changes to work that way," of improbable.

Or just the opposite. It could be a situation we have foreseen, and we simply don't have a good exit strategy, so we crash the program on purpose. Often because we are relying on exception handling to generate error reports before the whole thing crashes through to OS error message and program termination.

There's a very big difference here. By the late 30s, nuclear reactions were fairly well understood. There were still a lot of questions about the source of the binding energy, but certain isotopes becoming unstable on neutron capture was well known phenomenon, and various relevant cross-sections have been experimentally measured. We had all the math and science to explain how a reactor would work. And nobody was skeptical that it can work in principle. There were simply a lot of people skeptical about feasibility of a controlled reaction. And most of these people were not actual nuclear physicists. The later have had a pretty good consensus on the subject. What we have here is a system that has no explained mode of operation. No mathematical model that predicts its behavior. And all of the serious scientists agree that it can't work as advertised, that something else is going on. The only place where this looks similar is in a mind of a layman. And that just doesn't make a difference.

That's "fox tail" in the plume. It indicates presence of high quantities of nitrogen oxides in the exhaust. Specifically, nitrogen dioxide is the gas that gives it that red/brown color. Which means that they are still running tests with highly toxic fuels, like hydrazine variations and nitrogen tetroxide. And that means enormous environmental damage to the area. Smokestack or not, nitrogen dioxide gets captured by humidity in the air and percipetates very easily as acid rain/fog. Same goes for a number of other chemicals I'd expect in that plume, and they have even worse effects on environment and health. Khimki is so appropriately named. *sigh*

That's a tricky question. You definitely don't want one, long continuous chunk of ferous material. But you might want ferous rings in your coils. That can dramatically increase the mag field strenght, but it will also increase induction by the same factor. So if yo can build a sufficiently sophisticated switching system that counters induced EMF, you can get better output with ferous rings. But if you are simply switching coils on and off, induction will probably do more damage to final speed than what you get from stronger field. So if you are using a very simple switching system, then you should probably just have a plastic tube for a barrel, and have wire coils wound around it.

They will heat a lot of things. They are designed to be particularly effective with water, but there aren't a lot of things that you flat out can't heat up. That said, if your goal is to heat up a bowl, put water in it. It will not only absorb microwaves, but also help heat the bowl more efficiently, and prevent it from overheating. On that note, always be careful heating pure water in a smooth glass container in microwave. It's very easy to superheat the liquid, causing it to be above 100°C without boiling. In this case, sinceall you care aobut is heating the container, add something with the rough surface into the bowl with water. It will work like a boiling cork, preventing superheating. Water will just boil normally instead. And yeah, if you get it to boiling temperature, and give it a few minutes, it a good way to sterilize something. Very few bacteria can survive both room temperature and boiling water.

In this case, main cost is time. Just about everyone who has access to the right equipment, like vacuum chambers, and knows how to carry out the experiment precisely enough and accounting for all the variables properly, would probably consider it a wild goose chase not worth pursuing, because they have thier own research, which they actually expect positive results from. I'll admit, though. I'm starting to get curious. If I still had access to test equipment I'd need, I'd probably be running my own experiments by now.