swansont

My equations are for conservation of momentum and energy; they already assume the actual device is as efficient as possible. The way to maximize efficiency is to have the rocket mass be small and the ejected mass be large. Such as a bomb set in between a payload and a really, really big rock. You drastically change the ratio - if you have a 1 kg payload and 9 kg rock, your efficiency is now 90%. But that also means a really large acceleration, and you have no more reaction mass (if you did, that has to be included with the payload mass so it’s not 90% efficient anymore), so no more thrust or maneuvering. Doesn’t work for the visitation scenario.

One of the issues with matter-antimatter is that it’s an energy storage medium, like a battery that needs charging, rather than tapping into already-stored energy. You need to create all the antimatter ahead of time, so that whole energy investment is up front. — Let’s look at a snapshot of a rocket that carries its own reaction mass. The ejected mass m is sent away at speed v, and the rest of the rocket has mass M and recoils at V. This is in the rest frame of the system as the mass is ejected. Conservation of momentum dictates mv = MV, so (mv)^2 = (MV)^2 Meaning the ratio of kinetic energy of each is KErocket/KEexhaust = m/M i.e. if, in some small time increment, you eject a kg of exhaust, your million kg of rocket (payload+fuel+superstructure, etc) gets one millionth of the energy of the exhaust. That’s a reason why rickets are multi-stage - you are shedding mass to improve the efficiency. But you can only do that if you don’t need that superstructure anymore, which is not the case if you want to, say, enter and leave some gravity well (or wells) after your trip. It only works as a one-off, like our trips to LEO, or to the moon, or probes/orbiters

Yes, but only as compared to a less-efficient method. There’s a minimum, i.e. you can’t be more than 100% efficient, but it can’t even be 100% efficient. No matter what you throw out of the back of a rocket, it has energy. You can’t transfer all the energy to the payload.

It also a matter where you are; you aren’t going to accelerate upward unless your thrust or lift exceeds the gravitational force. It’s why ion drives aren’t used until you get away from the planet. NASA’s best gives you about 100 milliNewtons of thrust https://science.nasa.gov/mission/dawn/technology/ion-propulsion/ (similar argument for using photons)

In the US you can advertise supplements that aren’t considered drugs, and have not undergone the tests that drugs do to show safety and efficacy, but you can’t promise a cure for anything. So they always use weasel phrases; people will say it worked for them (but not that it works in general), they will say clinically tested (but not that the tests showed anything), the ads will tout how many have tried it and people will give anecdotal remarks like “I’ve used it for ten years and I feel great”. Basically they can sell placebos as long as they don’t overstep. If they do overstep they pay a fine which might be a small fraction of their profits, so it’s not necessarily a deterrent

TIL that bananas will enrage honeybees, because they contain isoamyl acetate (aka isopentyl acetate) which is a main component of the bees’ alarm pheromone https://blythewoodbeecompany.com/blogs/news/put-down-that-banana-beekeeper

The energy to move from one place to another in a gravitational field is not affected by the method, A 1 kg object moving up 1 meter on earth requires 9.8 Joules because that’s the change in potential energy. You can devise methods that use different forces acting for different distances or times, but the minimum energy you need to supply is the same. The method affects how much energy is wasted on whatever it is you’re throwing out of the back of the rocket. That dictates the efficiency.

AFAICT the point of this thread is the issue of some kinds of AI potentially not being objective and the legal implications of that. There are certainly lots of examples of the failures of LLM objectivity, so is that really in question? (Lawyers are being chastised and even sanctioned for using AI to generate documents) I pointed out early on that machine learning and LLMs are not synonymous, and I think it’s a mistake to treat them as such; you need to make these distinctions to have a productive conversation. Is anyone claiming that deterministic or probabilistic simulations are AI? (and even without that your summary of events of the plane landing doesn’t jibe with the NTSB summary; the simulations were used well after the fact) As iNow suggested, the objectivity/fidelity/reliability has to be adequately demonstrated before they will be accepted. We have examples of things not accepted in court because they fall short.

Calculating the minimum energy it takes to launch a payload to orbit, or to interstellar space, doesn’t depend on the method of propulsion. Same for getting up to a certain speed. The detail of propulsion matters for how much energy is wasted, i.e. how much more you need than the minimum, and you can calculate that for different scenarios. None of that analysis is included in saying “slow boat” or “we’ll refuel along the way” The science is in the details.

And there’s no science here to back this up. But there could be. You still have to have fuel and reaction mass to travel, to slow down at the destination, to do a controlled entry of a gravity well and to leave. None of that requires knowing the specific energy source, but the analysis could tell you how efficient of a method you’d have to use, which rules out certain (perhaps all) approaches But a blanket statement? Not scientific.

I’m trying to point out the differences between the kinds of arguments. I don’t think you can say a claim is scientific if there is no or scant mention of the science that allegedly buttresses it. If there is, then there is an opportunity to point out errors or omissions. (people - scientists included - can be wrong. Science relies on consensus because it’s less likely that errors are missed when multiple people check your work). So if there’s no science in it, it’s not scientific, even if a scientist makes it. Further, I think one can distinguish between arguments that might be missing information and those that violate principles we have very good reason to conclude are true. You can’t engineer your way around e.g. a violation of conservation of energy, or momentum

How is something claimed by a non-scientist, or before science existed, be considered scientific? Something rejected/resisted owing to religious dogma is not something you can ascribe to science

One issue is that “AI” is too vague of a description. That event took place in January of 2009. If an algorithm was involved, it’s not the LLM chatbot that’s being critiqued these days. But I can’t find any mention of this in the summaries of the accident. There is mention of running simulations as part of the investigation. https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR1003.pdf Page 2 shows the exchange between pilot and tower. The controller asks if the pilot wants to return to LGA, and the pilot says no. Nothing about an AI. Where did you get that?

Nobody said they aren’t real. The question is if they are scientific. Can you point to the scientific reasoning behind the claims? Kelvin explained his reasoning; it suffered from not accounting for convection and not knowing about radioactivity. Scientific means one can critique the analysis and point out errors. If that analysis is not present, it’s not scientific. It’s a guess, or an appeal to conventional wisdom. The site linked in the citation doesn’t contain this claim. Your annoying AI might have hallucinated this

Sure. Here we’re discussing visits that would generate a typical UFO/UAP report, i.e. enters our atmosphere, maneuvers, and then leaves. The fuel burden of getting here at 0.1c was addressed in the article, but it did not address the considerable obstacle of also entering and leaving a gravity well.