TheVat

I think somewhere along the way, you got the impression that the north pole analogy was meant to be an example of physical forces. The analogy was for the benefit of another member and was specifically about how geometry (in the analogy, of a sphere with designated poles) can create the illusion of a force. I'm sorry if that wasn't clear. All the stuff you're posting about free fall and so on I'm well aware of, as I had thought my posts had made clear. The polar trip analogy is only about imagining a mysterious force (i.e. an illusory force) which seems to be drawing two objects (starting at different longitudes) together and seeing how the illusion arises from converging lines of longitude. As an analogy, it is in no way, shape or form intended to provide some comprehensive bookkeeping on the actual forces acting upon northward moving objects. Hope this clarifies it. The experience, on my end, has been something like showing someone young how seasons work by shining a lamp on a globe and someone keeps objecting that the sun is really much farther from the earth and the globe should really be much smaller. All true statements, but not really germane to the simple concept that is being demonstrated.

My analogy was to the difference between a force and a pseudo force, with reference to geometry, not really about the details you speak of. It's an analogy I've heard pro physicists use. If it works better for you some other way, that's cool. If you reread my original comment, I hope this will be clearer in this context. If I'm speaking of G as a pseudo force, then of course there is still the electrostatic force from atoms of the earth on my atoms, resisting my normal free fall along a spacetime geodesic. ETA: if you're more comfortable with, say, the coriolis effect, that can also be used as an example of an analogous pseudo force. As the missile launched towards the north pole seems to veer off-course this is not an invisible force but the effect of a rotating reference frame.

Irrelevant to my analogy which is that there's no invisible force pulling objects towards each other as they go towards the north pole. Forget the bumping part. It's just the geometry of a sphere.

Seems like many scientists opt for methodological naturalism, which is to take an "as if" approach to math descriptions of phenomena...the math works "as if" objects are following a curved spatial path in the areas where there are large masses. One can use the math but remain agnostic as to spacetime actually being curved. So one can call G a pseudoforce or a force, depending on how far you are willing to go with the curvature description. @zapatos and I start walking towards the North Pole and we will eventually meet as we travel a curved surface. Since we believe the Earth's curvature is real, the "force" that causes us to bump into each other at 90° N is understood as a pseudoforce. If you don't like breaking Ockham's razor, you probably would prefer to take curvature as real rather than devise some complex scheme where space is actually flat but all these things keep manifesting redshifts, delays, lensing and deflections that weirdly imitate a curvature of spacetime.

Well, all the news reports are that Gaza is sealed up by Egypt and Israel. Where did you see reports of Gazans being allowed to leave? The only leaving I've seen is people being forced to evacuate Gaza City and flee to temporary refugee camps elsewhere in the Strip. Where many are now starving.

Not well read on Pratchett, but possible that Going Postal might be more accessible than some of his others. I recall the second Sprawl book, Count Zero, did this rather well, and rather audaciously imagined AIs which broke up into splinters that manifested as Haitian voodoo gods. Also rather prescient in its view of techno-billionaires struggling for dominance. Yep, Ringworld (and early sequels) were the sort of imaginative romp where you might like the vast setting and adventure and mind boggling engineering but would have to "take the best and leave the rest" -it's very much of its time. I own the first paperback printing, which has a famous error in which Louis Wu goes the wrong way around the Earth to prolong New Year's partying, and there are only a few copies extant (most of that press run was recalled by the publisher and shredded). Apparently it's worth something. It's fortunate that I've kept it sealed in cling wrap and in a cool dry basement for decades, since its high-acid pulp paper deteriorates pretty fast.

Glad you mentioned them. I'm not sure Gibson stills owns up to being American, having fled to Vancouver long ago. Agree that his cyberpunk novels do have that nostalgic element. Same goes for Bruce Sterling. I still haven't read Neal Stephenson's Snow Crash, which apparently makes me only semiliterate in cyberpunk circles. Also should mention the whole transhumanism SF subgenre, of which Charles Stross is a notable example. Absolutely mind-blowing stuff.

ETA - after all that rambling, I just want to name one novel, which I consider one of the finest get-your-feet-wet introductions to the genre: Ringworld, by Larry Niven.

I sometimes like to say that when I became a SF (which stands for the broad category of speculative fiction) fan, I never walked past the start of the alphabet (not really true, and I did eventually reach Vernor Vinge, Connie Willis, Gene Wolfe and Roger Zelazny. But early readings did seem to be the ABCDs - Aldiss, Asimov, Anderson, Bradbury, Bester, Clarke, Dick. Later, I encountered an alphabetical phenomenon which actually has a formal name among fans, the Killer B's of Hard SF which, if memory serves, includes Gregory Benford, Stephen Baxter, Ben Bova, Greg Bear, and (my favorite bee) David Brin. (For the newbies to SF, "hard SF"' refers to the more science-anchored subgenre of hard science fiction which emphasizes plausible and accurate use of science as central to the narrative) For an introduction to the broad genre, one could try an anthology - libraries will often have such, annual collections with titles like year's best SF, or there are thematic anthologies on a certain topic like, say, time travel or robots or first encounters with ETs. Those are a great way to get introduced to a variety of authors and see who you like. My anthology intro was a couple, one called Dangerous Visions (late sixties), edited by Harlan Ellison (the eccentric madman and jester of SF circles, back in the day), and the other called Orbit, which was a series of anthologies edited by Damon Knight. And don't overlook mainstream authors who have stepped over into the SF genre to produce notable work, from Margaret Atwood to George Orwell to Doris Lessing. And finally, those who use SF as a vehicle for comedy and satire - Doug Adams (as already mentioned), Kurt Vonnegut, R.A. Lafferty, Terry Pratchett and John Scalzi, to name a few. Not that I'm a SF fan or anything.

Not knowing where your encounters are happening, I wouid guess they are not with sources that give the broad scope of atmospheric science. Dozens of different metrics out there - sea ice, glaciers, foliage coverage, atmospheric gases, oceanic dissolved gases, average cloud cover, soot deposition, water/air/soil/permafrost temps, oceanic currents and turnover, albedo, growing season changes, wildfire incidence and severity, sea level, species habitat movements, storm frequencies and severity, coastal erosion, and that's just off the top of my head. There are others which all monitor change and volatility as more energy is injected into these complex systems. I hesitate to recommend NOAA, given the current idiot troll fascist trying to undermine federal information websites, but I would guess they still have stuff like this up there. If not, we can still rely on European agencies, like Copernicus Climate Change Service or ESA (European Space Agency) Climate Change Initiative or European Environment Agency. All have public and searchable websites IIRC. Just to offer a local example from my corner of the world - 50 years ago, the cold and aridity here meant no mosquitoes or termites. They just couldn't live here. Now they're moving in. And first and last frost dates, on average, have shifted to add one to two weeks of growing season in this general region. (In the US, land grant universities collect a lot of data on such metrics, due to their importance to agriculture and weather prediction) Hope that provides you a few leads - I'm sure others will have some suggestions, too.

My heart goes out to those in Lisbon who died or lost loved ones in the terrible funicular accident yesterday. This famous song was composed to commemorate the opening of the first funicular on Mt Vesuvius - I'm not posting it frivolously or to make light of a tragedy, but just as a musical nod to the history of the funicular and the love that it inspires.

Well yes, that I knew already, but I meant that I had thought it applied to anything using the counterbalance system. But apparently, as your wiki cite also mentions, it is a "type of cable railway system that connects points along a railway track laid on a steep slope..." IOW, I had erroneously thought funicular applied more broadly as to include suspended gondola systems (which may also use counter weighting). Also learned that some carry water tanks which can be filled at the top, if more weight is needed (e.g. fewer passengers coming down). The blanket term for the ones that suspend a gondola or seat up in the air is aerial lift. Gondola lifts, chairlifts, aerial trams, and funifors are some of the subcategories detailed here... https://en.wikipedia.org/wiki/Aerial_lift

The difference between a funicular and a gondola cable car. I am sorry people had to perish in Lisbon last night in order for me to understand the correct terminology. Funicular always means on tracks, going up a surface, often with a passenger compartment on gimbals or similar so that it stays level. The gondola cable car is the one that terrified (or would have, if that scene wasn't so ludicrous) in Moonraker. I.e. hanging over the void from a cable which, if you're a tourist, you hope is up to date on its inspections. And is free of Bond villains with sharp metal teeth gnawing away at it. Come to think of it, pretty much every Hollywood movie with a gondola car depicts it as a death trap.

I think it's safe to say that many Americans have little or no knowledge of the workings of global reserve currencies.

Didn't Schrodangler work out the math on this already? Possibly Max Planck first raised these questions.

If one is just skimming the new posts and eyes land on that sentence, one can briefly wonder what sort of physics they're doing around here.

You guys are really being 509 about Roman numerals.

Seems part of the growing body of critique around TESCREAL. A critical perspective I very much share, if that hasn't been obvious in my postings. https://en.wikipedia.org/wiki/TESCREAL According to critics of these philosophies, TESCREAL describes overlapping movements endorsed by prominent people in the tech industry to provide intellectual backing to pursue and prioritize projects including artificial general intelligence (AGI), life extension, and space colonization.[1][4][6] Science fiction author Charles Stross, using the example of space colonization, argued that the ideologies allow billionaires to pursue massive personal projects driven by a right-wing interpretation of science fiction by arguing that not to pursue such projects poses an existential risk to society.[7] Gebru and Torres write that, using the threat of extinction, TESCREALists can justify "attempts to build unscoped systems which are inherently unsafe".[1] Media scholar Ethan Zuckerman argues that by only considering goals that are valuable to the TESCREAL movement, futuristic projects with more immediate drawbacks, such as racial inequity, algorithmic bias, and environmental degradation, can be justified.[8] Philosopher Yogi Hale Hendlin has argued that by both ignoring the human causes of societal problems and over-engineering solutions, TESCREALists ignore the context in which many problems arise.[9] Camille Sojit Pejcha wrote in Document Journal that TESCREAL is a tool for tech elites to concentrate power.[6] In The Washington Spectator, Dave Troy called TESCREAL an "ends justifies the means" movement that is antithetical to "democratic, inclusive, fair, patient, and just governance".[4] Gil Duran wrote that "TESCREAL", "authoritarian technocracy", and "techno-optimism" were phrases used in early 2024 to describe a new ideology emerging in the tech industry.[10]

I just realized "Let's drop everything and go study gravity" would be a nifty title for a popular science article. Also, just checking, is necessity still the mother of invention? Or is the maternity being contested?

Three of you have asserted this here (and thanks all for replies), but my earlier question is still broadly: how would we empirically verify the nature of truly empty space. Even the voids between galaxy clusters are still within a particle horizon of something material and so can be affected. Can we assert that a void such that all matter is beyond a particle horizon, where nothing is causally connected to that void, must still have topology and fields and vacuum energy and permittivity and so on? It sounds like I'm going off on a Rovelli limb and a bit beyond, asking if even topology or geometry can be real where there is nothing to interact or have a metric applied.

The technical term for that is snackology. Which is similar to the Kama Sutra, except it has only the positions you deserve.

Fair point. I figured that might be mentioned. For some reason, space seems more that way, perhaps because I am unclear as to what properties of space are intrinsic to it. An electron has a particular charge even in an otherwise empty universe, or does it? (so ridiculously hypothetical I know, but hey it's the phil sandbox haha) So would one say that space has a particular property in an empty universe? Would vacuum energy still mean anything? I admit I'm floundering a bit, so any flotation device welcomed.

Even early math used very little of what we think of as math, i.e. algebraic equations. Pythagoras had his famous "proof by rearrangement" which used only geometric arrangement.

This being a phil thread, one could ask if space is anything more than a bundle of properties around matter. Without matter/energy, and translation or rotation, where would this bundle go? -- volume, permeability, permittivity... would be meaningless.

Yep, and to take a WAG, I would say the earliest empirical gathering of observations were probably more in the area of seasonal changes, solar and celestial bodies positions, animal behavior, and plants. (i.e. astronomy, zoology, and botany were "mothers")