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Here is the thing, though. With very few non-critical exceptions, all of the technology we are using is based on physics that was already around during Victorian Era. I could explain absolutely every detail of operation of a Space Shuttle to somebody from Victorian Era in terms of science they could understand. Moreover, from a good popular description they'd be able to workout almost all of it for themselves. They wouldn't be able to build one, but they'd know how it works. Theoretical physics is way, way ahead of technology. Yes, if we start talking about what's possible and not, we'll probably be trying to figure out how to fire a rocket out of a cannon. But if somebody suggests a piece of future technology to us, we can analyze it pretty well. And I don't know about you, but my computer doesn't run on wood gas. There is just way too much technology in ST that should have been displaced. This isn't even about science. It's just common sense.

Not the way they have them on the show. I have a suspicion that all of their technology is antiquated salvage ran by wizards pretending to be engineers. Moreover, none of the wizards are aware that other engineers are also wizards, so they are constantly trying to "fake it", all the while making stuff happen with magic under the table. It's the only explanation I have for the techno-babble and inconsistency of explanations and effects.

So is space-time curvature. Thing about modern physics is that questions of, "Is this really how it works, or is this just a mathematical trick," become kind of meaningless. How would you tell the difference? More than one. But Casimir Effect is still the only one that's been experimentally verified, and even there we're far from understanding the whole thing. Winter Man mentioned zero fluctuations, and that leads to vacuum having energy. Unfortunately, when we try to predict how much, we end up with a value that is in disagreement with cosmological models by many orders of magnitude. P.S. Actually, the more puzzling question is why we don't observe negative energy. The only requirement from field theory is that the stress-energy tensor is a conserved current. In non-relativistic limit, that means energy, momentum, and angular momentum are conserved. But it places no restrictions on the sign. In fact, we have no trouble giving momentum or angular momentum any direction we wish. It's only the energy component, which is associated with time-direction, that insists on being positive definite for some reason. A blind stab in the dark is that it is related to direction of time flow, but that only makes the whole thing more convoluted.

Map time matches ship's proper time under warp. That's the whole point of a warp drive. In "0.5 'local perspective years'," you can make the trip in completely flat space-time thanks to SR. You just need a really big rocket. There are no assumptions beyond these of standard theory. Because if you don't understand it, it's all just buzzwords to everybody else, right?

Partial pressure doesn't mean anything. The question isn't just about concentration. It's about how much energy is produced in the reaction and how much stuff there is to soak that energy up. So only volume ratios matter. And by volume, CH4 requires 3x the oxygen to burn. That means that at 5% in air it's already very lean. Adding more oxygen makes very little difference, because there isn't enough methane to combust with. Reaction rate is going to be improved in pure oxygen, but without lowering activation energy, it will make little difference to LEL. So 1.5% Methane won't burn even in pure oxygen. And you still have 98.5% of other stuff, mostly nitrogen, to deal with. Catalysts are the only thing you listed that will make a difference. Organizing catalyzed combustion chambers, however, is rather tricky. I don't think you'd be able to run a jet engine on that, and even if you could, it wouldn't be worth the trouble. By this point, it's a lot cheaper to just bring both fuel and oxidizer to run the turbine.

Nope. Won't even burn at that concentration. Edit: Because it actually just came up elsewhere, the LEL for Methane is 5%. So you have to have at least that much methane in atmosphere to allow for combustion.

Casimir effect results in a space-time region which has qualities of the negative energy density which you need for a Warp Drive or a traversable wormhole. People have been looking into it for a while. The net energy is still positive. It's a bit like having a bubble in a glass of water. The bubble behaves as if it has negative weight, but it doesn't make the glass lighter. But there appear to be ways to make it work for the warp drive. A lot of this is still in the air, because math for anything beyond the basic Alcubierre Drive is very hairy. But there is also a lot of progress being made. When Alcubierre's paper was published, the estimates for the energy were greater than mass of observable universe. With some improvements, people shaved it down to a large planet. Latest research manages to use oscillating field to drop this estimates to less than a ton, and that's a quantity of energy we can comprehend. It's still more than we can produce in a controlled fashion, but we're getting there. The math, though... It's honestly not that bad, but it requires a lot of background. I mean, the fundamental equation is just ADM metric with some parameters. Once you know the metric, it's just algebra to compute required energy densities. And relationship between parametrization of the metric and trajectory of the ship has already been worked out for you. So it's just plugging numbers into the equations. Understanding why all of that works, or being able to derive variations on the drive, requires thorough understanding of General Relativity. Without getting into specifics, what allows it to work is the fact that speed of light is a local limit. Two things close to each other cannot move faster than c with respect to each other. But once you have sufficient separation, this is no longer true. You can absorb superluminal motion into coordinate system choice, and this gives you space-time curvature with specific energy density distributions as a consequence. In other words, by achieving this specific energy distribution, you force the desired metric, and then your ship can go as fast as you like relative to remote objects. Understanding Yang-Mills and Noether's Theorem helps to see why these things are related in such a way, but not, strictly speaking, necessary. You can understand almost all of GR from perspective of differential geometry without diving into underlying field theory. If you want to learn the actual math and understand how all of this works, you should start with Linear Algebra, learn Calculus, some Analysis would help, Differential Equations, Topology, and just the basics of Differential Geometry. Then if you want to understand the underlying physics, you need to learn Classical Mechanics, Electrodynamics, Quantum Mechanics, Group Theory, basic Quantum Field Theory, just a bit of Relativistic Quantum Field Theory, and get a good enough grasp of Yang-Mills to understand connection to Differential Geometry picture. That's where you start getting a general idea of how all of this works.

It's not a black hole. It's just a system that allows radiation to escape by a similar mechanism. There is no event horizon there.

That's useful information. Tidal forces can be manageable for a large enough black hole, but the force required to keep an object stationary diverges as you approach the horizon. So yeah, there is no way to hold a planet in place as far as we know.

There is no such thing as an artificial black hole. Experiments were done on analogous system, but there is some doubt on whether they are reliable. Sag A* is, however, a strong radio source. That might have been the radiation Dominatus was thinking of. It is consistent with what we expect from a black hole, yes.

That's absolute nonsense. At energies of 7TeV, which is the most you get per nucleon at LHC, the corresponding Schwarzschild Radius is on the order of 10-50m. That's 15 orders of magnitude smaller than Plank Length. Let alone nucleon size, which is on the order of femtometers. There is nothing even remotely close to a singularity being produced at LHC.

What gave you that idea?

A turbojet is going to burn through about half of the available oxygen, and afterburner will burn through almost all of the rest. For example, Concorde's Olympus 593 Mk 610 pulls 186kg of air per second. In dry cruise, it will inject 4.7kg of Jet A per second into that. So out of the 42.8kg of O2, 18.8kg will be consumed every second in the dry stage. That's nearly half. With afterburner engaged, fuel consumption more than doubles, taking care of the remaining oxygen. The purpose of the turbojet is to operate at high speeds, and if your overall exhaust velocity is low, you start losing efficiency at high speeds. To increase exhaust velocity, you have to increase the fuel-to-air ratio. This means that even on a commercial airliner, which is all about efficiency, even the dry stage will consume a lot more than a "small fraction" in cruise setting. While punching through the transonic region, the engine will run almost stoichiometric ratio. Running a turbojet very lean is just pointless. A lean mixture will have a much lower combustion temperature, reducing the overall efficiency of the turbine. You are much, much better off having a turbofan design and simply allow the air to bypass the combustion chamber. That allows you to maintain high temperatures and increase reaction mass. The only reason a turbojet typically runs a bit lean is because you need a lot more thrust punching through the transonic and because temperatures the turbine can take are limited. So it makes more sense, both from perspective of engine longevity and fuel efficiency, to have an afterburner which lets you run a stoichiometric mix when you need it, at a cost of a slightly reduced thermodynamic efficiency of both stages. When you go to even higher speeds, even that provision no longer applies, and you are looking at engines that run close to stoichiometric mix even in cruise. But then, you typically aren't going to be looking at turbines at all, but rather a ram jet of some sort. I'm pretty sure I covered that in the first post in the thread. Except that running a turboject by mixing ambient atmosphere with fuel and oxidizer is a really inefficient idea. You are far better off running a turbine on just the oxidizer and fuel, without mixing in ambient air, and then using turbine's output to spin a compressor or a prop that uses ambient atmo as reaction mass.

Orbital mechanics in proximity of a black hole is pretty straight forward, actually. Circular orbits with r > 3rs are stable. In other words, you can have an object orbiting a black hole just an event horizon's diameter away from the same. For a small black hole, we could be talking about tens of kilometers. Of course, if we are talking about a planet, its orbit can't be closer to the black hole than the size of the planet. There are also tidal forces to consider. There is going to be an equivalent of the Roche limit within which any planet would get torn up and become part of the accretion disc. So something planet-sized would have to be placed a bit further away, but it can still be very close. Without knowing a bit more about the specifics, like the size of the planet, its composition, and distance from the black hole, I couldn't really tell you for sure whether such a thing is going to be possible. But in general, it's entirely plausible. There are circular orbits that close in, but they are not stable. The object in orbit would require some station-keeping. Plausible for a ship, but not for a planet. Stable orbits start at 3x the radius.

There was an article that talked about comparison of a rocket to a molotov cocktail, which pointed out that a typical rocket, has a higher fraction of fuel to total mass than the molotov. Gives you an idea.

I still don't see how that definition applies, but so long as our disagreement is on semantics, I agree, it's not important.

There is no such thing as absolute velocity. How fast something is moving is absolutely irrelevant. In station's frame of reference, the docking port is static. What matters is how the target is accelerating. And docking port is accelerating radially at precisely 1G. Exactly the same as any point on the surface of our planet. Yes, in case of VTOL aircraft, atmosphere can make things easier. Or a lot harder if there is cross-wind. But that's why PakledHostage mentioned Apollo 12. They were operating in identical conditions. They had to match velocity of the surface and then land on it while matching the Moon's surface gravity. There is no difference here.

It does not. There is not an event that leads to a decay. Decay is the event. It's quantum physics. There are processes within the nucleus that contribute to both decay modes. Like, a lowest order process leading to β+ starting with a valence up quark undergoing flavor change and emitting a W+ boson. But you can't say that emission of W+ is the circumstance, because it's not something that happens or not happens. All of the processes are taking place, and all of them are contributing to the final outcome. Typically, a gamma burst from a β+ annihilating an electron is your first indication that what took place is a β+ decay. And it's not a limitation of measuring equipment. It's literally when the outcome is decided.

The difference between docking to a rotating and non-rotating station is precisely by the accelerated frame of reference. And as we've discussed, that's the same problem that a VTOL aircraft has to deal with. There is no significant difference between fighting gravity and trying to match rotation with a rotating space station, so long as station is large. And something on the order of B5 or larger is definitely large enough. It's not the most fuel-efficient way to dock. I would probably need close to two minutes under full thrust to do the docking, so we are talking over 1km/s of dV reserve. But in terms of difficulty of flying approach, it's really not that bad as I intend to fully demonstrate.

I would definitely go with modules for reasons of not only structural integrity, but also safety. However, keep in mind that if I take two rectangular rooms, each one pressurized, and put them together so that they share a wall, then by taking out the wall, the only thing I lose is the tension support the wall provided. Stress on all other walls remains exactly the same. Which means I can replace a wall with some pillars. Taking this to the bigger structure, I can have fairly large open spaces, so long as I'm willing to tolerate an endoskeleton of supporting frames. The downside is that the mass of the station will scale with volume, rather than surface area. But that's a well known problem with pressurized containers.

Have you done docking in KSP? That's done at over 2km/s. Have you had difficulties with these colossal speeds? Or did you find that only the relative speeds matter? Because it should have been the later. Coriolis effect is proportional to angular velocity. So is every other problem you are likely to encounter. The larger the station, the easier it is to land on using conventional VTOL techniques. Now for structural stress, it's actually pretty simple. Station rotates at a uniform angular velocity. So we can consider it from a co-rotating frame, in which the only source of structural stress is the centrifugal force. Centrifugal force is proportional to ɲr. Because É is constant throughout, it just increases linearly from center starting at 0G and growing to 1G at the rim. What this means is that you are basically building a suspension structure. Making one that's several km in diameter is an engineering challenge. But it's well within the structural strength of modern building materials. Alright. I've gotten basic handling in "Earth's Gravity" sorted, so I'm just going to keep the current parameters. Going to start building the station now.

They never specifically shown it, but it was implied that there are elevators going every which way from the cargo bay. For example, if you recall, arrivals/departures were in normal gravity section. Passenger shuttles would be carried down from the cargo bay before they'd be allowed to disembark. They've shown that in a few places. The fact that something similar happens to fighters is merely implied, but given how thought-through everything else was, I wouldn't doubt that creators thought about it.

Your window of opportunity is almost as big as you want to make it. First, we agree that we can set up a pass at an almost arbitrary distance from the station to have ship at rest at closest approach, right? There is question of precision, but we aren't trying to grab a dumb cargo drone with a station. We don't need it to pass within inches or even meters of the station. If you can give me +/- 50m, I'd shoot for a 100m approach and it'd be fine. Rest can be covered under power. Ideally, you need to go from free-fall to accelerating at 1g precisely as you pass under the station, at which point you are hovering and the rest of approach is trivial. Realistically, you can't do that, but you don't need to, either. What you do is start throttling up a few seconds in advance, which will bring up the line of closest approach closer to the station, curving in your trajectory. So long as you watch the time to closest approach, closest approach distance, and your velocity relative to the station, it's a pretty straight forward maneuver with a window in tens of seconds at 1G. I'm sure that what you were working on required a perfect approach precision and an instant transition from inertial to accelerated movement. This is not the case with a ship being flown by an experienced pilot. It's just not the same problem. But you know what? I'm prepared to bring it down to a simulation. I have a VTOL simulation I've written a while ago. With a few modifications, I can get it to simulate something space-worthy. All I have to do is get rid of all of the aerodynamics code, modify thrusters a bit, change the control scheme, and add a bit more info on the HUD. Oh, and I'd have to model and simulate a simple station, I guess. That will require a few extra bits of collision code, but it's no trouble. What I need from you are parameters you are willing to accept. Specifically, with what precision you would allow me to measure my velocity and position relative to the station? I'd also take accelerometer data and combine it with tracking data via Kalman filter. So I need error on acceleration data as well. And what about the Shuttle? For simplicity, lets say maximum linear and angular accelerations you'd allow. Naturally, I need something in excess of 1G along the vertical axis. Everything else will be pretty gentle, but I'm worried if I just make up numbers you'll accuse me of rigging it. As for the station, lets say 40 RPH as mentioned earlier? That would put the station's diameter at about 4km to provide 1G at the outer edge. That's a nice big target to aim for. I can do either a wheel-type station or a tether. Your call. Yeah, they did. Fighters returned through the same docking bays as general cargo. They show it a few times. The point is that launch needs to be instant. If it takes a while for fighters to come back, get loaded onto lifts, transported to the launch bay, and re-mounted, that's fine.

There aren't any special circumstances. It's totally random. One in more than 10,000 2He will undergo a β+ decay, the rest decaying back into a pair of protons. And not a thing you can do about changing these odds.

That last bit is all you needed to say. But yeah, good catch. Nitrogen in the atmo is going to make a big difference in favor of a turbojet. Point stands, though. If you are flying through an inert atmosphere, you can get better efficiency by having completely isolated turbine and compressor stages than trying to feed fuel and oxidizer into combustion chamber of a conventional jet engine.