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  1. There are several parallel issues here. One is that wealth acquired by the ultra wealthy tends to get put into tax shelters and nebulous investments so it grows (but remains outside the system), whereas that same money in the hands of the less fortunate goes IMMEDIATELY into the community around them. They spend it on groceries and vehicle repairs and school clothes for kids and paying the electricity bill so it’s not dark in their apartment anymore at night and their kids can read. The providers of those goods and services in that community where this money is being spent ALSO spend the money once received for THEIR groceries and THEIR service needs and on THEIR kids. Dollar for dollar / unit for unit… the money in the hands of the less fortunate does more net good than money in the hands of the already fortunate. Yes, spending from the wealthy also creates jobs and injects money back into the system, but very little relative to money used in “trickle up” stimulation packages. Also, a bit of extra money in the hands of someone who already has a bunch of it doesn’t tend to change their behavior or encourage extra spending. Getting $1,000 tax break when you’re sitting on $50M isn’t going to suddenly result in them finally making a call to a plumber or the purchasing a new dishwasher… but for the person living paycheck to paycheck that money literally changes lives, gets spent and injected back into the system quickly, and results in lasting reductions in poverty and suffering. When you’re living at the margins, every dollar counts. It also costs a lot to be poor. When the washing machine breaks, you can’t afford a new one but you can afford to pump quarters into the machine at the laundromat… but that ends up being more expensive on net. When the car breaks down, you don’t get to work on time and you get fired. The rich, however, have tax protected ways of growing their wealth and can afford tax attorneys to hide it. Paying more tax has more impact on their ego than on their lived experience. The anger at the rich is out of hand, though. We need better policies and enforcement mechanisms, not more hate and vitriol directed at those doing better than us. Sadly, the anger is probably in large part intentionally being amplified by the very people on the receiving end. If they can keep everyone mad and focused on the wrong things, then the status quo remains stable and no progress or change gets made. Like most issues in economics, we make a huge mistake by treating it as a moral failure when at its core it’s a policy failure. Fixing the policy is just super hard because the people with the power to change the laws tend to be the same ones benefiting the most from them… and also because focusing on wonky policy details is hard for a public who’s often just trying to survive through to tomorrow and who’d much prefer throwing stones and being distracted with us/them tribalism. Perhaps this thread could try focusing on wonky policy details instead of distractions like yachts and steel boats… or not.
    5 points
  2. I think the biggest change is the internet. 20 years ago if you said the earth was flat your friends and family would laugh and say, "no that's not right" and you would find no one to agree with you. Now you can go on the internet and find hundreds or thousands of people who will agree with whatever batshit crazy idea you have.
    3 points
  3. Unless I'm misreading things, and adding in my own thoughts, I suspect it is not Davy that is missed but the conversations he generated among the other members. I'm thrilled he is gone as I hate his type of approach to discussion. I find it very rude and disingenuous. On the other hand, like with the many trolls who occasionally roam our halls, I learned a lot as people made honest attempts to educate him. It wasn't Davy who provided any insights, it was everyone else. I've never enjoyed burst water pipes, losing a job, or a serious illness in the family, but I am always better educated once it is over.
    3 points
  4. Hydrogen is not a power source. It’s a storage medium. Hydrogen technology is akin to battery technology. Hydrogen can only be as green as the power that creates it.
    2 points
  5. Just asking. Isn't Au (gold) a precious metal? It is good to see progress on better electrolyzers and I hope it flows through to renewable Hydrogen production. It won't become widely used without better electrolyzers. I see iron smelting and chemical feedstocks as the uses of most significance. I am less optimistic for H2 as transport fuel and as transportable fuel; iron production and chemical feedstocks can operate with on-site production and storage at low(er) pressure and therefore cheaper than bringing it from somewhere else. Battery electric looks better for vehicles - overall much higher energy efficiencies and piggy backs onto existing energy distribution networks. Hydrogen as transport fuel needs economy wide infrastructure built from zero. One more halving of battery costs will make existing type EV's unstoppable. One more doubling of energy density will make EV's unstoppable - and open up aviation to battery electric. Achieve both and it is game over for fossil fuels. Hydrogen won't be in that game. I'm cynical and think that, important as clean iron smelting and fertiliser production is too much is being made of Hydrogen - and the reason it has such widespread political support is that it can't do much any time soon. Those looking for empty gestures to follow up their empty gestures on zero emission targets like renewable Hydrogen sometime in the future, but so does the fossil fuel industry, that currently make most Hydrogen like it; it uses empty gestures on Carbon Capture and Storage to justify competing (with aid of subsidies from sympathetic politicians) against emerging clean Hydrogen and other clean energy.
    2 points
  6. 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.
    2 points
  7. ! Moderator Note It still violates rule 2.7 ! Moderator Note This isn’t a treasure hunt site, it’s a discussion board.
    2 points
  8. https://en.wikipedia.org/wiki/Whewell_equation Homework. No linear algebra or group theory here.
    2 points
  9. 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.
    2 points
  10. https://phys.org/news/2021-09-game-changer-hydrogen-production.html Graphical abstract. Credit: DOI: 10.1016/j.nanoen.2021.106463: Curtin University research has identified a new, cheaper and more efficient electrocatalyst to make green hydrogen from water that could one day open new avenues for large-scale clean energy production. Typically, scientists have been using precious metal catalysts, such as platinum, to accelerate the reaction to break water into hydrogen and oxygen. Now Curtin research has found that adding nickel and cobalt to cheaper, previously ineffective catalysts enhances their performance, which lowers the energy required to split the water and increases the yield of hydrogen. Lead researcher Dr. Guohua Jia, from Curtin's School of Molecular and Life Sciences, said this discovery could have far-reaching implications for sustainable green fuel generation in the future. "Our research essentially saw us take two-dimensional iron-sulfur nanocrystals, which don't usually work as catalysts for the electricity-driven reaction that gets hydrogen from water, and add small amounts of nickel and cobalt ions. When we did this it completely transformed the poor-performing iron-sulfur into a viable and efficient catalyst," Dr. Jia said. more at link................................... the paper: https://www.sciencedirect.com/science/article/abs/pii/S2211285521007187?via%3Dihub Ni2+/Co2+ doped Au-Fe7S8 nanoplatelets with exceptionally high oxygen evolution reaction activity: Abstract: To overcome the limited potency of energy devices such as alkaline water electrolyzers, the construction of active materials with dramatically enhanced oxygen evolution reaction (OER) performance is of great importance. Herein we developed an ion diffusion-induced doping strategy that is capable of producing Ni2+/Co2+ doped two-dimensional (2D) Au-Fe7S8 nanoplatelets (NPLs) with exceptionally high OER activity outperforming the benchmark RuO2 catalyst. The co-existence of Co and Ni in Au-Fe7S8 NPLs led to the lowest OER overpotential of 243 mV at 10 mA cm-2 and fast kinetics with a Tafel slope of 43 mV dec-1. Density functional theory (DFT) calculations demonstrated that Ni2+/Co2+ doping improves the binding of OOH species on the {001} surfaces of Au-Fe7S8 NPLs and lowers the Gibbs free energy of the OER process, which are beneficial to outstanding OER activity of the nanoplatelets.
    1 point
  11. 1 point
  12. My mother used to make jelly this way and it was tasty as well as having a pleasing texture. But in between her limited canning seasons, she bought a store brand jelly that was so stiff it ripped the bread when you tried to spread it. It tasted of grapes and children's tears. Ah, I forgot about how teeth can break down Jello viscosity! The culprit is one of your school's second grade teachers! I remember my eighth grade English teacher drawing a couple of stick figures holding a circle with a dot in the middle of it between them. She asked me what it was, and when I couldn't guess she said it was "two men walking abreast". Of course, this calls for my only jelly joke. In the midst of the Y2K panic in 1999, the KY Jelly company announced it was Y2K compliant. They called it Y2KY Jelly, and it allowed you to put all four digits in your date....
    1 point
  13. I think that is a big part of it. Fundamentally, we are utterly unprepared in dealing with social media. Or rather, our psychology is not well suited to deal with it. Fundamentally the issue at hand is one of trust. Few folks have the expertise and time to evaluate each claim they encounter and there is at best a superficial, intuitive evaluation of the facts. Moreover, we are prone to trust folks that we know or feel that we know more. In societies without with no mass media that makes a lot of sense. However, eventually mass media created celebrities. By seeing folks on a regular basis, even if one a screen, it creates the illusion of familiarity and this is why celebrities have a disproportionate influence on public opinion (see their role in promoting anti vaccination sentiments over the last decades). Now with social media, that effect further extends to random folks, youtubers and so on. Those folks are more trusted than individuals with actual expertise, in part because the latter are busy working in their field of expertise than using psychological tricks to make folks like (and subscribe) them. You can see that effect in classes now. College students increasingly cite random youtubers as sources of information, which I find rather worrying (and I used to be worried about wikipedia in the past). So the combination of a big network of trust without expertise and mistrust of gatekeepers seems to create a system where outrageous misinformation can speed happily along, leaving fact checking and similar slow measures in the dust. And I will also say that this is not an US-specific problem.
    1 point
  14. Colossus? 2010 was pretty good; in fact, one of the best depictions of AI and its potential problems. My SO's constant, rankling beef about Star Trek is the "synchronous orbit" where you see the planet rotate by underneath, and yet they never lose contact with the away team. That, and the "full stop" - in space. Mine is: You've developed warp drive and teleportation, but lost the concept of seatbelts and lanyards. Oddly, these niggles never stopped us watching the shows.
    1 point
  15. This is for you @Peterkin...
    1 point
  16. Those were not incidents involving hydrogen. Hydrogen has one property which makes it rather more hazardous than natural gas- it has a very low ignition energy. On the other hand, the low molecular mass and comparatively low energy density (a litre of hydrogen carries less energy than a litre of methane) tend to reduce the risk. to exactly the same extent that it will leak through a badly made connection, it will also leak out of the area it is released into. There's a story of a demo where they emptied a tanker truck of liquid hydrogen onto the surface of a lake, waited 5 minutes and struck a match. They then invited anyone to do the same with petrol/ gasoline. Any fuel is, ipso facto, potentially dangerous. The way round that it to not let it escape. Not really. Once you tighten up the fittings so that the metal meets the metal, there's no hole. Practically speaking, Hydrogen won't diffuse through a mild steel pipe any more than propane will
    1 point
  17. Also it seems to me that OP sees SF in a very narrow context. The genre has almost always been more a commentary on society and its development rather than the application of science to a literary genres. In fact, more often than not, the "science" part is just the vehicle to make a point (similar to the purpose of, say, monsters in fantasy). There are of course notable exceptions where the science part is heavy and sometimes is considered under the genre of "hard" SF. As a whole it is but a small slice of the overall SF picture. As such one could expand the question to ask whether fiction or even literature is bad for society.
    1 point
  18. I'd put documentary above SF - they at least attempt (the ones I'm tempted by) to be factual, but I find I struggle to keep watching the doco's too; the last time I tried the overly dramatic background music and awestruck narration was just too much. And I was familiar with most of the content, so not much that was new. SF unfortunately presents a fantasy vision of Humans in Space that references the F of other SF far more than it references S. They get so much so wrong that I can't look past the mistakes. Whether back in my youth, when a space monster blocked the air intakes of the ship of Lost in Space - the Robinsons were going to asphyxiate (even then we thought it was stupid) - or my failed attempt to watch "Expanse", that others consider very good. Having the SF standard tyrannical and corrupt UN running Earth badly in Expanse was mildly irritating but I know most people who like SF will be Americans who have been taught to dislike and distrust the UN, so it hits their buttons (but annoy me) and there is an independent and powerful Mars (colonising Mars is inevitable, right?); these are the kind of tropes that get used to suit viewer tastes I don't share. But it was the water shortage on Ceres that lost me. Seriously? They are a major mining operation but they don't know you can heat carbonaceous chondrite material and get water? And don't they do recycling? There are some SF writers (of novels) that I enjoy a lot but very little of TV or cinema SF can grab me; it is the ones that don't take themselves seriously, that are unashamedly fantasy or comedy or both that are most likely to appeal to me.
    1 point
  19. The other side of this coin is that people are telling them not to trust, and to not get the vaccine…but the people at the top of the pyramid are vaccinated. It’s interesting seeing the shock of the drones at finding out e.g. FOX news has a vaccine mandate. It’s related to having authoritarians and grifters in power, and the way to show loyalty is to believe what they tell you rather than what you see with your lying eyes. It’s the price of belonging to the tribe.
    1 point
  20. Only in a rough sense; fission and particle ejection are classified as different reactions. Particle ejection can be endothermic, so you need an energetic particle to cause the proton to be removed. Almost certainly required if you eject more than one. Fissionable materials are typically very heavy nuclei, and fissile materials are a small subset. Particle ejection candidates are found over almost the whole range of the periodic table.
    1 point
  21. Well, I wonder then how reliable remote systems are. After all, presumably airplanes can also be controlled remotely and much of the flight is automated, anyway. In either case we presumably do not have real safety data to actually figure out whether having a manual backup (and hence a need for a pilot) would improve safety. As the flights are presumably very short and few in numbers it might not make much of a difference, but I think at this point one can only rely on massive extrapolation to form an opinion.
    1 point
  22. It's a cognitive gap, apparently. The Craig. T. Nelson problem. Granted, he's only a millionnaire, so maybe that doesn't count.
    1 point
  23. (with thanks to new member @Doogles31731 for sending this)
    1 point
  24. Correct - but with the caveat that the concept of ‘gravitational potential’ can only be meaningfully defined in certain highly symmetric spacetimes, such as Schwarzschild. It is not a generally applicable concept. Indeed. It vanishes locally in those regions, but not globally. Yes, correct. Think back to your math lessons in high school - remember how you drew simple graphs such as y=x^2. No question that the graph is globally curved. But now imagine you were to choose some point (eg x=2), and zoom into the graph there. What happens? The more you zoom in, the flatter it will begin to look. It’s just like that. This takes a while to really get your head around. I’m sorry I won’t try to offer a proper answer here, as typing LaTeX code on an on-screen phone keyboard is just too cumbersome and time consuming. What I will say though is don’t focus on the components, but on what objects you pass to the tensor, and what you get out as a result. Rough outline: Imagine you have two test particles, whose world lines are initially parallel. Now choose a point on one of these world lines - take the unit tangent vector at that point (which is physically just that particle’s 4-velocity). Then, still at that same point, take the perpendicular separation vector that connects it to the other particle’s world line. Now imagine the Riemann tensor as a machine with four slots (the four indices). Input the tangent vector into slots 2 & 4, and the separation vector into slot 3; leave the first slot empty. The output of the machine then is a new vector (because we left one index open) - it tells you how fast the separation between the test particles begins to change, and in what direction (relative acceleration between the test particles). Writing this down in math notation immediately gives you the geodesic deviation equation, bearing in mind that we need to use a covariant, not ordinary, second derivative. So the Riemann tensor is a machine that takes the tangent vector on one world line, and the separation vector between them as input; and produces as a result an acceleration vector that tells you how that separation between particles changes over time (geodesic deviation). This deviation can be a combination of any space and time direction, and can be complicated - you can get the world lines twisting around one another in a helix configuration, and all kinds of fancy stuff like that. This is really most of what there is to it in a GR context - Riemann has other uses as well (eg one can calculate tidal forces from it), but I won’t get into this here. It does in fact reflect all possible degrees of freedom of gravity. The individual components of the tensor represent tidal effects between various combinations of directions, but I really don’t think it’s helpful to try to look at it this way - it won’t help you understand. Better to think of it as a machine with slots that take an input, and produces an output; with the indices of the tensor being those slots. Any tensor can be conceptualised in that way - eg the Ricci tensor takes a future-pointing time-like unit vector into both slots, and produces a real number that is the rate at which a small volume changes when in free fall. In vacuum R(u,v)=0, so in vacuum a small volume in free fall is conserved (but its shape will get distorted, which is described by a different tensor). Inside a matter distribution, neither volume nor shape would be preserved. (Note carefully that this geometric interpretation only holds so long as there is no expansion, shear, or vorticity, which is true for most simple spacetimes) Hopefully this makes any kind of sense to you.
    1 point
  25. It's an obsession that is more akin to a religious obsession I suggest, in spamming his propaganda/philosophy, and ignoring the prime issue and question at hand. jealousy?? envy?? or a political obsession?
    1 point
  26. 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.
    1 point
  27. 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.
    1 point
  28. A very insightful comment, without any need to refer to index notation. +1
    1 point
  29. Why is this not in Homework ? Hints What is s ? What is velocity in terms of s? What is acceleration in terms of velocity ?
    1 point
  30. 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.....
    1 point
  31. 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.
    1 point
  32. 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.
    1 point
  33. 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.
    1 point
  34. Try not to think about a fog that swirls around you quickly before vanishing, leaving you unexpectedly covered in bugs! STOP!
    1 point
  35. Stromatolites. Amongst the first living organisms on earth circa 3.5 billion years ago and still going today. They were responsible for releasing the oxygen into a toxic (to us) atmousphere and making it breathable for oxygen breathers. https://www.bushheritage.org.au/species/stromatolites https://en.wikipedia.org/wiki/Stromatolite You may have seen the BBC series The Power of the Planet, presented by Iain Stewart https://www.bbc.co.uk/programmes/p00gczg5 An interesting reverse (geological not biological) process is the 'rusting of the rocks' https://www.newswise.com/articles/how-rocks-rusted-on-earth-and-turned-red
    1 point
  36. You mention origami. There was an Institute of Origami in my home town, back in the 70s, but it folded.
    1 point
  37. 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)
    1 point
  38. Look it up on the internet. There is no point in anyone here paraphrasing widely available basic science. If you have a more specific issue, by all means come back here and ask about it. If you are not a bot, that is.
    1 point
  39. +1 to Markus for his patient conversation and explanations to Conscious Energy.
    1 point
  40. There isn’t really any kind of ‘action’ in the mechanistic sense of the word. It’s just that test particles and their world lines are themselves part of spacetime, so they cannot do anything other than follow its underlying geometry. There’s no duality of any kind. See below analogy for clarity. As I’ve mentioned in my last post, there is information, in the form of the metric which determines the relationship between points. So it isn’t a ‘zero set’. This is true even very far from any sources - even spacetime without gravity has geometric structure that is different from that of Euclidean space. This is (eg) why you can’t accelerate to the speed of light - the fundamental reason for this is geometric, so geometry has real measurable consequences. It’s exactly like the calculus you learned at school - the derivative of a function is defined at a single point, yet gives you information about the slope of the entire function. That’s because what it really does is tell you about the relationship between neighbouring points on the graph of the function - how it changes from point to point. If you’re given just the (local) derivative, plus boundary conditions, you can reconstruct the entire function, even though any one single point of the function is just an (x,y) pair. To give an analogy (!!!) - suppose you have two people starting out on different points along the equator, and flying north simultaneously at a constant altitude. When they start out on the equator, let them be - say - 1000miles apart. What happens? The further north they get, the smaller the distance between them becomes. Eventually they’ll meet at the pole. Why? There is no detectable ‘action’ or force between the two planes. Each plane starts off at 90 degree angle from the equator (so their trajectories are initially parallel), and they always fly straight (there’s never any detectable change in direction from their initial trajectory). Yet they approach one another. That’s because they are both confined to the surface of the Earth, which is a sphere; so they must follow its intrinsic geometry. The metric governing this has real, detectable consequences. There is no detectable information about this at any one point on the Earth’s surface. This is because the geometry concerns relationships between points, so what you do is take measurements of path lengths, areas, or angles. For example, you’ll find that the sum of the angles in a triangle on Earth’s surface is no longer exactly 180 degrees - it’s possible to directly measure this deviation. But you can’t do it at a single point, you need to measure across some distance. That’s because the effects of a non-flat metric are accumulative - mathematically, you integrate components of the metric to obtain path lengths. To put it differently, the metric defines an inner product of tangent vectors, so it’s a local object, but with global effects across the manifold. Similar principles are true for curved spacetime as well. You can measure path lengths through spacetime pretty much directly (Shapiro delay, Pound-Rebka, gravitational wave detectors,...) and find that they differ from what you’d expect in a flat geometry. You can also directly measure angular distortions in the geometry, ie gyroscopic precessions, frame dragging etc. Gravitational light deflection is in effect a demonstration of the angle sum in a large triangle being different from 180 degrees close to a massive body. And so on.
    1 point
  41. I expect that most people who don't want to pay taxes for taxpayer funded community education still like being part of a community that gets educated - they just want businesses and people other than themselves to pay for it, ie they want to get the benefits without paying for it. Businesses are advantaged by the availability of educated employees - as they benefit from healthy employees. Similarly they also benefit from employees of other companies being well paid, via strong consumer demand - but not want to pay their own well. I suspect the wealthy get more overall benefits from the services governments support through taxes than any other demographic - law and order to protect their wealth, infrastructure to support their business activities, educated workers, healthy workers. Programs that reduce inequality don't only divert money from the successful (deserving) to the unsuccessful (undeserving) they also reduce the risks of crime and social disruptions that, if allowed to grow can lead to riots, terrorism and militant uprisings. Education is a key pathway to sustainably reducing poverty across generations and that not only benefits the individuals and their families directly but benefits their neighbors and businesses and their owners and the State and Nation. I think the illusion that governments are like companies and running them like businesses would do it better is widely promoted and feeds popular opposition to taxpayer funded education and other "social" programs - but governments are not companies; where companies fire unproductive employees and costs are avoided they stay on the government's books whether they are productive or not and those kinds of costs resist being avoided.
    1 point
  42. Given that rates are historically low and practically zero, they have literally nothing BUT opportunity to raise them, significantly or otherwise. How so? One of the 'controls' used to keep inflation at manageable levels is variance of lending rates. Once the citizenry has taken on too much personal debt, the ability to raise lending rates has to be used very carefully ( or not at all ) as it would lead to massive defaulting on debt, bank failures and recession. As in 2008. We realized, then, that unrealistic debt levels were a problem, and stricter controls over borrowing were solutions, yet in my area, home ownership has become impossible or young pople, due to house prices doubling in the past two years ( over 1/2 Million is entry level ). Scarcity of rental property ownership has resulted in skyrocketing rents, and increased homelessness Have we already forgotten ?
    1 point
  43. 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.
    1 point
  44. 70 posts, some of them have involved a lot of work and I still don't understand the basis of what you are saying about dimensions. Most of what you have posted assumes the reader understands and agrees with your basic statement about dimensions. I don't understand or agree. You mention unit analysis and also Tesla. There is a form of analysis in electrical power engineering called 'per unit' analysis. I don't know if you are trying to emulate this. The problem with 'unit analysis' is that the dimensions are hidden in the 'units' employed. They haven't really gone away. So can I respectfully suggest you put some of this effort into developing (proving) your underlying claim once and for all? Perhaps showing one simple example developed from start to fininsh, but involving as many as possible of the seven basic quantities in the LMTAθIN system. For your information here are two free websites where you build mathematical formulae and copy/paste into ScienceForums. http://www.sciweavers.org/free-online-latex-equation-editor https://www.codecogs.com/latex/eqneditor.php
    1 point
  45. Possible? Yes. Probable? No. Please try going with just a little bit less ridiculousness and a little more reality in future posts. It will be appreciated.
    1 point
  46. Did you just really suggest people are using deep fake video tech to falsely make it look like things in Afghanistan are kinda horrible for lots of people right now? GTFOH with that special brand of crazy sauce
    1 point
  47. Interesting video by Dr. John Campbell on the current state of affairs with Covid. https://www.youtube.com/watch?v=VL8QnUM81Wo
    1 point
  48. An ion lifter as described doesn't work in outer space; you need to ionize air molecules for them to work. But you are correct, it wouldn't be collisions that create the thrust, but the reaction from the motion of the ions you have created.
    1 point
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