sevenperforce

Adding the magnet can alter the baseline state of the system but it cannot continuously maintain a temperature difference to function as an endless heat sink. The reason a magnet doesn't work is because of the same reason the Brownian ratchet doesn't work. A magnet will have a continuous field, and so even though the orbitals on one end will be strengthened and orbitals on the other end will be weakened, the continuity of the field means there is no actual point where the more energetic particles are induced to cluster more on one side than the other. On the other hand, if you have a system where you have shifted the parameters in both boxes with an actual discontinuity at the center (and only at the center) then you will have the endless heat sink effect. If it was possible to construct a magnet with a discontinuous field, then building an overbalanced wheel would be trivial.

BE-4 doesn't need subcooled propellants to reach its highest performance levels. BE-4 runs at lower turbopump pressures and thus may be more readily reusable than Raptor. BE-4 has a single turbopump rather than two turbopumps and therefore has fewer failure modes. Of course all these are trade-offs.

The best explanation for light speed ramming, I think, is to suppose that the mass budget for missiles is better used for packing hypermatter warheads than anything else. All of the engines in Star Wars are supposed to run on hypermatter. So while it would be theoretically possible to build a missile that functions on light speed ramming, it should actually deliver much more energy by simply using the same mass budget for a hypermatter warhead. The only reason that Holdo was able to cripple the Supremacy using light speed ramming was that the Raddus was an enormous ship.

All SW ships, even the very small ones, have repulsorlifts which act only along a gravitational gradient but consume very little energy. So the ion engines are only used for flying out of the atmosphere or flying back down into it. And there's no orbiting, either; you just fly out of the atmosphere and hover up there. Hyperspace drives are for moving large distances through space. Of course they sort of broke that in TROS when the Falcon was lightspeed skipping, but I suppose it did a lot of damage to the ship so there's that. You can tell this is the way it's all conceptualized. In Revenge of the Sith, General Grievous sabotaged the Invisible Hand and hopped out in an escape pod, leaving the ship to plummet toward Coruscant. If it was in orbit, it would have remained in orbit. You can also see this in Rogue One during the Battle of Scarif, when three Y-wings disabled the engines on the Persecutor, causing it to suddenly begin dropping. Its backup generator reactivated the repulsorlifts, but the Lightmaker was able to push it into the Intimidator and all three ships subsequently dropped like stones directly into the Shield Gate, destroying it. Finally it's also visible at the beginning of The Last Jedi during the bombing runs; the bombers all attempt to fly over the Fulminatrix in order to simply drop their bombs but only the Cobalt Hammer manages to release the bombs before being destroyed. Once it does so, however, the Fulminatrix begins to explode and it immediately starts to plummet. If the ships were in orbit; dropping the bombs would do nothing. This also means that there typically isn't actually antigravity being used. If you had a repulsorlift and could hover above the surface of a planet, you'd still be subject to gravity whether you were in the atmosphere or not.

Yes.

Still, we kept the Apollo astronauts in quarantine for three weeks.

I wonder if theoretically it would make sense to do a potentially biohazardous sample return to the ISS. On the one hand they have fewer containment measures. On the other hand they are one gigantic containment measure.

We do have stock buoyancy. Unfortunately it only operates under the oceans.

That's the whole problem with the exercise. You have to assume that there is no unification of forces and that you can alter stuff arbitrarily. Sure, that's fair. If you change the strength of the electromagnetic fields (actually in this case you might have to screw around with QM and Pauli repulsion), then the kinetic diameter of the gas particles will change, and the mean free path of more energetic particles will be greater on one side than the other. This in turn breaks the ideal gas law, and at the interface (which actually can be quite large) you will have more energetic particles passing through to one side than in the other direction. But there are any number of ways to build a daemon. Depending on how your manipulation of fundamental forces is designed, you can simply build a Brownian ratchet that really can only move in one direction.

42-43 m/s was with all flaps fully extended, which probably isn't even a stable configuration. Because the flaps have a much higher drag coefficient than the cylindrical body, they represent 46% of the total drag even though they are only 27% of the total cross-sectional area. Since terminal velocity is inversely proportional to the square root of surface area, that means folding the flaps all the way back could increase terminal velocity to 62 m/s. Also, that animation starts at 3K feet, where the air density is 10% lower, further decreasing drag. Finally, my mass estimate is based on the production Starship, which could be much lower than these prototypes.

But you cannot make it time-dependent via the application of an external electric field unless that electric field draws energy OR unless you have advance information about the Brownian energies of the particles. That’s where information, entropy, and energy find equivalency. If you want to build a Maxwellian daemon by manipulation of the fundamental forces, then put two boxes next to each other and put a door between them, and then modify the electromagnetic field properties of the electrons in the molecules. On one side you reduce the electromagnetic field strength and on the other side you increase it. Faster-moving, more energetic particles will move through the door preferentially from the high strength to the low strength side, and there’s your daemon. That’s if you want to build Maxwell’s demon. If you want to just generate endless energy, then build an overbalanced wheel and adjust the masses of the weights on one side in real time. Spin it forever.

I'm talking on Twitter with the guy who does the really awesome Starship animations and I'm actually a little surprised by the numbers I'm getting for Starship's terminal velocity:

His net worth via stake in Amazon is currently $185B but yes, haha. People say "Bezos made $2B this week" because that sounds like an amazing sum of money but they are ignoring how stock prices work. Based on stock price fluctuation, Bezos lost $2,480,000,000.00 in the last hour and a half, which comes to an "income" of negative $1.1 trillion per month.

No matter how conclusively it is proven that the life originated independently, the sorts of religious groups which deny deep time and think humans put saddles on T. rex will inevitably claim "there are other interpretations".

I'm reminded of Doctor Who.... Oxygen is a lifting gas on Venus.

No, the demon was independent. With a Maxwell's Demon and a thermoelectric generator, you can put the ends of the thermocouple into fluid baths with a door separating the two. Use the demon to preferentially select higher-energy Brownian particles for one side. Infinite energy. If you have control over the fundamental forces then you can construct a Maxwell's demon trivially. Yep, unification is the tricky bit! Ultimately all the fundamental forces are part of the same set of interactions and so you can't change one thing without screwing up other things...but it's fun to speculate regardless! I love this part.

Well, yes. That's the trick. That's why fundamental forces cannot be changed willy-nilly. I ran into this back in my creationist days. "Can't you just change the speed of light so light gets there faster?" No, because the speed of light is an intrinsic property of the causality relationship of the universe. Change one thing, and everything else goes to pieces. People don't think about it, but the ability to violate the second law of thermodynamics would instantly give rise to the ability to violate ALL the laws of thermodynamics. If you can take a box of hot and separate it into hot and cold without an external heat sink, then you can literally rule the universe. You can take a box of hot, make half of it cold, then use a heat engine to extract work from it...then repeat, forever. If you have a heat engine containing an infinite amount of work, you can produce arbitrary amounts of electrical current to power lasers to produce a kugelblitz or mass via pair production or literally anything you want. Waste laser heat can be recycled via your "box of cold" to increase efficiency. Break anything, and you break everything.

If you can arbitrarily adjust the fundamental forces then you can alter quantum chromodynamic binding energy for certain hadrons and not others, resulting in the formation of a closed loop that annihilates and forms particles endlessly with net positive energy production.

If you have control over fundamental forces you can generate infinite energy by setting up a Maxwell's demon, creating an infinite heat sink, and then recycling entropy. You can change coupling energies so that decoupling is more energetic on one side of the box and less energetic on the other side.

Yes. Literally. Of all the absurd things that Pre-Crisis (or Post-Crisis, even) Supes can do, his ability to ignore the second law whenever it suits him is the most absurd one. If each of Superman's cells is a tiny Maxwell's demon, then he really needs no further superpowers.

If you have the ability to alter fundamental forces at will, you can build Maxwell's demon. If you can build Maxwell's demon, you can use Doppler cooling to make mincemeat of the Second Law. You have an infinite entropy sink. A "box of cold" that never heats up. A heat shield with infinite ablator. Not only could you fly through the sun, but you could build a condominium on the surface of the sun and sell timeshares.

Yes, readily. If you can manipulate the four fundamental forces at will, you can use the Higgs mechanism to generate arbitrary amounts of mass. Of course you will have to deal with heat and pressure comparable to the interior of a neutron star, but that's fine because you can manipulate the four fundamental forces at will. Or you can skip the Higgs mechanism altogether and just build a photon rocket. If you can manipulate the fundamental forces of the Standard Model at will, you are so far beyond needing a nuclear thermal rocket that it's silly. It's a little like using microprocessors to design a turntable that adjusts the position of a sundial to keep it properly aligned with the position of the sun throughout the year. Yes, you can do it, but if you have microprocessors you really don't need a sundial anymore. Using fundamental force manipulation to generate reaction mass for a nuclear thermal rocket is like 3D-printing a steam engine for a locomotive.

Life doesn't need water. You could rather easily have life which uses liquid hydrogen sulfide or sulfuric acid or pretty much any covalent molecule as its primary solvent and metabolic base. It's easier if it's a diamagnetic molecule like hydrogen sulfide so that you can get hydrogen bonding. My chemistry-fu is probably my area of greatest scientific weakness, but I'm sure that someone with better chemistry chops than myself could come up with a closed-loop metabolic pathway involving phosphoric acid, phosphine, hydrogen sulfide, carbon dioxide, sulfur dioxide, and some sort of acid anhydride. The bond energy for carbon dioxide is 4.2 kJ per mole, while the bond energy for sulfur dioxide is on the order of 1 kJ per mole, so if you have life that is based on the reduction of sulfur dioxide to carbon dioxide there's a lot of potential energy there.

If I had the inclination, I could run the numbers and get a very good idea of dry mass and actual capability. This is good data. The RL10CX is 3D-printed but other than that I have no idea what its performance is like. Tory says ">>451" which is a shocking claim. Are we talking about something on the order of the 460.1 seconds of the RL10C-3? Or more? The RL-10C-2-1 on the DCSS pushes a blistering 465.5 seconds. And the RL10B-X which would have been mounted on the Centaur B-X space tug clocked in at 470 seconds with an expansion ratio of 250...although that is lower than the expansion ratio of the RL-10C-2-1.

The Superheavy launch mount is looking more and more exciting. It is possible (though unlikely) that they ultimately will not test SN7 to burst. If they get plastic deformation at a high enough pressure they might say "welp looks good" and stop there. If you can establish that all of your welds are good and the superstructure undergoes plastic deformation without failure, there's really no utility in blowing the sides out just for fun.