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I couldn't agree more. I think the sooner we make this discussion less political and passionate, the better for the flow of ideas on a topic that interests us all. I don't want to commit an opinion yet. I want to consider more arguments. Very interesting topic BTW.

! Moderator Note It still violates rule 2.7 ! Moderator Note This isn’t a treasure hunt site, it’s a discussion board.

https://en.wikipedia.org/wiki/Whewell_equation Homework. No linear algebra or group theory here.

So kind of you to be willing to fall on your sword for such a noble cause but no one cares if your comment was political or religious or cultural. The point is it is off-topic. beecee is asking about technical risks, not your feeling about worthless rich people, the entertainment industry, or pollution.

There are several ways to handle catenaries, but I often find that splitting the vertical axis into two with one section constant and the other parallel to the horizontala axis, as in the following.

Why is this not in Homework ? Hints What is s ? What is velocity in terms of s? What is acceleration in terms of velocity ?

No, this one is new to me. Thanks for bringing it up. Having skimmed through the link, my first impression is that this formalism is not nearly as elegant and intuitive as the standard one (and full equivalence with GR is yet to be shown). I kind of fail to see the advantage, though the point about substructure is interesting. See studiot’s comments on intrinsic vs extrinsic to begin with. Furthermore, there is not really any force involved in gravity - when you have initially parallel test particles in free fall, and attach an accelerometer to them, it will always read exactly zero, so no forces; nonetheless in the presence of gravity their geodesics will begin to deviate. Good question! This point is a bit subtle, and really the answer should be “both of the above, depending on context”. The physical manifestation of curvature is geodesic deviation - meaning that initially parallel world lines will begin to deviate as they extend into the future. It is thus necessary for world lines to have at least some extension in spacetime before “parallel” and “deviate” even make sense - you can’t speak of parallelism at a single event. Thus curvature has measurable meaning only across some distance. I’m highlighting the word ‘measurable’ because counterintuitively the mathematical object describing curvature (Riemann tensor) nonetheless is a local object, like all tensors. For clarification on this point, refer back to the example about calculus in my previous post. However, there are also scenarios where the effects of gravity are in some sense ‘relative’. Consider a hollow shell of matter, like a planet that has somehow been hollowed out (not very physical of course, but I’m just demonstrating a principle here). Birkhoffs Theorem tells us that spacetime everywhere in the interior cavity is perfectly flat, ie locally Minkowski. There’s no geodesic deviation inside the cavity. Now let’s place a clock into the cavity, and another reference clock very far way on the outside, so both clocks are locally in flat Minkowski spacetime. What happens? Even though both clocks are locally in flat spacetime (no gravity), the one inside the cavity is still gravitationally dilated with respect to the far way one! This is because while both local patches are flat, spacetime in between them is curved - if you were to draw an embedding diagram, you’d get a gravitational well with a ‘Mesa mountain’ at the bottom; and the flat top of that mountain sits at a lower level than the far away clock, thus the time dilation. So in this particular case one could reasonably say that gravitation effects are ‘relative’ between local patches. Or you can put it like this: both regions are Minkowski, but one is more Minkowski than the other The isn’t very intuitive, but mathematically perfectly consistent - if you look at the world lines of the clocks, you’ll find that while they appear parallel in space (they’re simply at rest wrt to one another), they deviate in spacetime. In GR it is crucially important that one fully understands local vs global, or else there’ll be no end to misunderstandings and problems. This point is where most, if not all, apparent ‘paradoxes’ in GR arise. In general, no, it’s not a scalar - it’s a rank-4 tensor field, the Riemann tensor. However, you can choose to look at only certain aspects of curvature, such as how volumes change (rank-2 Ricci tensor), or how areas differ from Euclidean counterparts (rank-0 Ricci scalar), or the average Gaussian curvature of a small region of space (rank-2 Einstein tensor). But to capture all aspects, you need the full rank-4 tensor with 20 independent components. Tensors are not invariant, but covariant - meaning their individual components do vary in just the right ways so that the relationships between the components remain, hence the overall object is the same for all observers. Remember a tensor is all about the relationships between its components.

I'm asking for opinions...You have given yours...thanks. Not everyone is as smart as you. 🤭Perhaps there decision/s are wrong. You take it easy, you sound rather edgy...🙄 Again the question/s stand.....Are they too confident in attempting a still rather dangerous venture, without a professional on board? Is it a wise and appropriate thing to do considering the safety of thehumans on board? [be they billionares or not] https://theconversation.com/spacex-inspiration4-mission-sent-4-people-with-minimal-training-into-orbit-and-brought-space-tourism-closer-to-reality-167611 The future of space tourism? Sending a crew of amateur astronauts into orbit is a significant step in the development of space tourism. However, despite the more inclusive feel of the mission, there are still serious barriers to overcome before average people can go to space. For one, the cost remains quite high. Though three of the four are not rich, Isaacman is a billionaire and paid an estimated $200 million to fund the trip. The need to train for a mission like this also means that prospective passengers must be able to devote significant amounts of time to prepare – time that many ordinary people don’t have. Finally, space remains a dangerous place, and there will never be a way to fully remove the danger of launching people – whether untrained civilians or seasoned professional astronauts – into space. [Over 110,000 readers rely on The Conversation’s newsletter to understand the world. Sign up today.] Despite these limitations, orbital space tourism is coming. For SpaceX, Inspiration4 is an important proof of concept that demonstrated the safety and reliability of their autonomous rocket and capsule systems. Indeed, SpaceX has several tourist missions planned in the next few months, even though the company isn’t focused on space tourism. Some will even includes stops at the International Space Station. Even as space remains out of reach for most on Earth, Inspiration4 is an example of how billionaire space barons’ efforts to include more people on their journeys can give an otherwise exclusive activity a wider public appeal. <<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>> https://phys.org/news/2021-09-spacex-tourist-crew-healthy-happy.html An Interesting mixture of the four all civilian crew.....

Pretty sure we had this same conversation about 6 years ago, but for purposes of this thread it suffices to say that it wasn’t debt. Summarized: It was forcing them to implement austerity from the outside when they needed the opposite. It was also a refusal to let them move to their own currency to make improving revenues more possible. Finally, the situation was made worse than it needed to be bc folks kept treating it as a moral / political issue instead of an economic one.

They don't seem to be clueless; I'm not terribly worried about their safety. I am, however, concerned that this is a one-off advertising gimmick - presumably to promote the newest fad in overpriced leisure activities, so that all future passengers are likely to be useless rich people, wasting jillions of dollars and fuel. Depending on the fuel used, they'll produce a significant to unacceptable amount of air pollution and CO2 emission . To no good purpose whatever.

A combination of reasons, as one would expect. Regulatory craziness is part of it, like how in the US you have to buy a car from a local dealership instead of a national chain or even direct from the manufacturer. Iirc, competition laws in Greece and Italy make forming large business groups difficult, so they don't benefit from economy of scale (such as small pharmacies that can't merge to form a CVS or Walgreen's). Then the small businesses have to employ a certain amount of people no matter what their industry is, and iirc more than half of Greeks work at small businesses. It's hard to make some efforts pay off if you have too many workers. They don't have a healthy mix of large and small business, imo. Unfortunately, corruption is worse usually in small business practices. Big corporations are more heavily watched and audited, and don't deal with as much cash. And corruption is what keeps many small businesses afloat that would otherwise have gone under. If you have a great business, it deserves to start small and grow on merit into a big business where it will be of more use to the economy, so the framework of small business tends to simultaneously give people a lot of potential to succeed and grow, as well as limiting their growth and making short cuts tempting. Plus the Greeks had borrowed heavily when they entered the EU (which they shouldn't have qualified for), and they suffered massive tax evasion from wealthy entrepreneurs so they had no revenue to pay back the loans. They also weren't as productive when using the new EU metrics, but still had access to all the borrowing power of an EU country.

Naked mole rats are not really rats, and they're not just any mammals: (Wikipedia) Sharks are also very resistant to tumours. I don't know what this has to do with beauty, but it does have a lot to do with the unexpected. Nature is truly amazing.

Thanks. Yes ,I thought of writing "Euclidean geometry" but was a bit uncertain as to the correct terminology "Natively" an auto misspelling for "naturally" I am guessing.(my bold)

Okay, then. You seem to have three main areas of complaint. The first and apparently most important is with the system of higher education. There may well be quite a lot wrong there, though probably not as much as there is at the elementary and high-school levels. There is also a vast range of education quality and availability across the nation and economic classes. The institution at which you did poorly may be an example of the low end - or even the unaccredited and fraudulent (Check for it on that list I linked in your other thread.) - and not representative of the whole system. BTAIM, your particular beef seems to be your inability to keep up with assigned work. Are any of your classmates having the same problem? Or is it that you need a specialized structure of study? Have you done independent study through on-air courses and library books to fill in the skipped/missed steps? No institution with an enrollment of thousands of ordinary students is ever going to offer a customized course for the exceptions - it's just not feasible. So you have to make your own. All the information, all the material, all the tools (except high end laboratory equipment) that's available to the universities is available to the public. When you have perfected the method of learning that works best for you and accumulated the requisite knowledge, go back to the university and take your exams for that degree. It will put you that much closer to selling your course of study to other students. Did you not have a course outline and overview to judge before you paid your money. I don't know whether, how or to what degree "the system" is broken - and neither do you. That's one of those meaningless pronouncements that makes the rounds of mass media without attracting very much reflection: "The system is broken." What system? What are the fractured components? How is it supposed to work? When was it whole and functional? And that's what I'm asking you to do now. Analyze your own problem as you have stated it above. You might even come up with your own solution. What is your source of information, where are your calculations and process for this comprehensive conclusion? I like to understand what I'm reading, too. It would be very helpful if you untangled your paragraphs, sorted your subject matter into categories and stated, in clear, concise sentences, what you think is wrong and how you think it could be made right - one problem at a time. And that's why I'm ignoring the bits about politics and responding only on the subject of education.

How should any of us know? It's their decision. They have the resources and information to make the one that seems right, wise and appropriate for each of them.

I'm sure they've made plans for various foreseeable problems. Nobody has plans for the unforeseen ones. Sometimes the rocket explodes and everybody dies - including the professional astronauts.

You are a slave to these sick people who pushed their sick fantasies to the extreme and then become self righteous and then made a career out of it. Science. You are a slave and you don't even know it but now that quantum computers will come they'll have full control of your life and then basically play god with it and then flick the off switch. We are all enslaved by the machine world - and have the illusion of freedom.

I didn't count them, but I know "filthy" isn't one I generally employ, as I don't consider t a term of endearment, and I have an unsubstantiated suspicion they don't, either. Why do you think I should be complimentary about the super rich? I am failing to take comfort from that. Indeed I did. He paid for all the seats. He is doing it for a hospital, which is very nice - but not a pre-requisite for space jaunts. No, there are lots, not heavily used. But that's the SpaceX is launching from. They're where I left them. Read as you please.

Hello sir] What is this software finacle bank

It's true. Women and kids are given a free ride and they are put ahead of men because both mothers and kids are fed a fantasy by the establishment that their daughters can be someone great. Even the court justice system is bias towards women than men... Sickness is profitable...Why do you think that love is a crime? You are a slave to religion because religion gets a free ride in everything. They also don't want you to breed so these rich people can stay rich while you stay as poor as possible which is why diseases are released in the wild but somehow treatment is readily available. You are a slave to the middle east people who get a free ride...they got to have cake and eat it too.