catmistake

I think it is far simpler than that. He is macho, and that is popular due to evolution. The meanest monkey has the most offspring, but the meanest monkey has turned into the one no one wants to fight, so he can risk being cuddly, but it is a act. The meanest monkey is still there.

FWIW Libertarianism is super trendy, but misguided, because, in a nutshell, it leads to tragedy of the commons, and ultimately, pure socialism.

Not quite right. Rather, either it is adopted by the adult entertainment industry first, then spreads to other spaces like medical applications, or it goes no where.

Fair enough. May I suggest that it is the depreciation of the family unit that may be causing this. Generally, in my experience, jerks had crummy parents. I don't know the solution, but maybe instead of treating young pregnant couples as sacred, we should make having children a privilege, not a right, and make them work for it. But I wouldn't know how to do that.

First of all, the complainers do not speak for me, yet they seem to be speaking for everyone, that everyone has this problem because of 24-hour notice of the release of iOS14.

Anyone that has a work flow, even a personal workflow having nothing to do with actual earning of income, that updates as soon as an update is available, is an asshole to themselves, and a compulsive one at that. If there are no security patches, bug fixes or features that I desperately need, I don't update. I'm still running iPadOS13.4 and I may never update.

The problem here is not Apple's. Apple can do as it wants, and is under no obligation to make things convenient for the egotistical developers. From my perspective, (and fallacy argument from authority here, but fwiw, I studied computer science, flunky career in systems administration, and I am perfectly aware I rarely did any computer science, but am also aware programming is not computer science, either... CS is just math, and that is all... I personally just liked the problem solving necessities that sysadmining provided me, along with a decent living... I enjoyed solving those puzzles), developing for iOS sounds easy as snot. Developing a killer app is more difficult in that it must be innovative, clever, beautiful, and useful. But 99% of the apps on AppStore, and including 90% of the games, are duplicates of stuff that has been around forever. Where is the innovation?

And I have very little sympathy for developers because most of them made my life a living hell for 20 years. It is that precious few that did the opposite that I love, nay, that I worship. What are the chances anyone in this group of developer blamers and complainers, borderline narcissist egoists, are among them? Slim to none.

Apple gave you excellent tools. You have your own source code. Get something done! It doesn't matter how long it takes. But with the tools Apple provides, seems to me it is loading the tools, loading the source, grooming the source for the update, clicking a few radio buttons, compiling, and publishing. Shut up and get something done, or bail and go develop for another platform. Jeesh. Make install not war.

about the deaths of millions of people when it comes to environmental destruction

You're not getting it. With global environmental catastrophe the concern is not about the deaths of millions of people. It is about the deaths of all people everywhere. A symptom of the problem of environmental catastrophe is those that are cavalier about the deaths of entire species of wildlife. The planet will be fine, the plant and wildlife will recover... though it may not be the same plant or wildlife. But once humans are gone, there is very little change we are coming back. So, to be clear, though humans have and are making he planet uninhabitable for myriad of species, reducing the available variety of species, which we, in fact, depend on... it is a web... but we are also making the planet uninhabitable for people.

Serious and monumental efforts in conservation of plant and wildlife and habitat is a damn good place to start. The more natural habitat there is, the more plant and wildlife there is, the better it will be for us. First thing is first... the oil industry and the chemical industry needs to go away within the next 10 years. Government, which people control, needs to make all that crap unprofitable. All pollution must cease, and we need to figure out how to clean up what has been done. Let's not bitch about energy, nor evangelize nuclear power. Let's just bite the bullet for a few generations and force everything and everyone to generate their own energy, and require that it be clean.

While Homebrew defaults to binary, it can build from source, though it tends to leave behind a bloody mess when it does.

MacPorts has excellent housekeeping, which is controlled through port command arguments. One can choose to leave everything from the entire build, or have everything cleaned up as it builds, or clean it up after the build. Showing and eliminating leaves is also pretty simple.

Uninstalling MacPorts with these 3 commands leaves absolutely nothing behind:

$ sudo port -dfp uninstall --follow-dependencies installed

$ sudo port -dfp uninstall all

$ sudo rm -rf /opt/local /Library/Tcl/macports*

Good luck completely uninstalling Homebrew without having to look everywhere to make sure it is all gone. It requires downloading and trusting the Homebrew uninstall script.

I recommend macports package management system, similar in function to BSD ports collection. Superior to Homebrew, the johnny-come-lately PMS with all the penguinista-style hype that seems to lean towards binary installs, unlike roll your own from all source in macports. Homebrew also does not honor the default privileges of /usr/local, which is an annoying security flaw.

Those special f/x are really slick. Always nice to see new Terminal development.

Ad hominem is not simply an attack; it's disparaging someone to undermine their argument.

Which is why it is also fallacy. Attacking the man does not undermine the argument, so the argument stands unassailed. Anytime we say "you..." it is the beginning of an ad hominem fallacy. Informal fallacy is invalid argument.

The rest of your last comment is all ad hominem fallacy. It's all you you you with you.

So in one breath you're saying GR would have appeared quickly if Einstein had not described it, and in the other you're saying he was the legend of his myth and productive his entire career.

It is simply my opinion that GR was so amazing, insightful, and non-obvious that it would have taken a similar miracle as Einstein himself for someone else to have intuited it and worked it out, but given enough time, eventually it would have appeared.

BTW, Einstein's most cited paper, by far, is from 1935, written when he was 56. I suspect that's some evidence he did good work after general relativity.

OR it is evidence that he had decent research assistants.

No, I was correct. Ad hominem is an attack. I have not attacked you, and I do not see how you could find ad hominem in my replies. Unfounded paranoia is probably not something you should ignore.

My point was very simply was that Einstein did not walk on water nor did he operate in a vacuum. I am not sure why this is so difficult to believe.

The specific fallacies you have chosen to employ to attempt support your frail argument are interesting. I have read Special Relativity in translation, it is short enough and there is little math. My German is not even pedestrian, so no, I have not read Einstein's original article on General Relativity.

No, I meant what I said. Special Relativity would have appeared within a few years of Einstein's publication had it not occurred, but for General Relativity derived elsewhere would have taken decades at least. Hilbert didn't have it and wasn't on anyone's heels.

I disagree as to your opinions, which seem to just disagree for the sake of disagreement. The elements of Special Relativity were around. I stand by the assertion that someone else would have developed that theory within a few short years had Einstein not. And I stand by the assertion that General Relativity, had Einstein not existed, would have taken several decades before anyone would have fully put it together.

For anything Einstein is given credit for after about 1918, it was just the momentum of his popularity. Anytime another name is on anything, it is that other name that did most of the work, and because it was based on Einstein's earlier work, his name went on it also. And this is absolutely normal and expected in academia. Nearly all physicists do their life's work before they are 30, usually by the time they are 23. Einstein was nearly 40 when he published his Theory of General Relativity, and that is extremely out of the ordinary. You are seeing things, perpetuating the myth, when you place Einstein, the man, central to any breakthroughs after about 1918.

I'd also like to point out that Einstein was humble, and the myth of Einstein that developed was not his doing. It was the common man, the everyday people and the press of the time that said, incorrectly, "wow! He is so smart, no one can understand what he is doing!" Which is patently false. Non-physicists could not be expected to understand Relativity. But the physicist peers of Einstein didn't have much trouble with it, contrary to Arthur Eddington's famous quote in response to the statement that only 3 people in the world understood Einstein, "I am trying to think who the third would be." False. Physicists of the day that looked at his work understood his work.

To Einstein's credit, one of the hallmarks of his genius, he had an ability to take complex ideas and describe them very simply, so that any might understand.

It is General Relativity that is Einstein's really only major contribution worth noting. And that is enough! Though he was first to describe Special Relativity, had he not, someone else would have within a few years of his publication. But had Einstein not given us General Relativity, it might have taken another 50 or 75 years for that to appear. But it also absolutely would have come from someone else had Einstein never existed.

Einstein is amazing, he is just not at all the myth that everyone thinks he was. He was just a humble theoretical physicist.

It is in the ballpark. The point is that Einstein did not pull a rabbit out of his hat, others had thought similar weirdness, and Einstein was aware of it.

Shamefully, everything is from Wikipedia, so the citations are there.

Fair enough, though I was comparing him to his peers and friends.

time dialation (something completely alien to all before him

No, not so much.

You missed this in my GP comment: "Hendrik Lorentz proposed that the motion of the apparatus through the aether may cause the apparatus to contract along its length in the direction of motion, and he further assumed, that the time variable for moving systems must also be changed accordingly ("local time"), which led to the formulation of the Lorentz transformation."

Keeping Dally on the payroll doesn't negate that he initially showed no regard for Dally's nor his own safety, which is a sociopathic trait. It does not make up for Edison's ruthless practices, nor his unbridled ambition and greed. Edison had no respect for Tesla, even cruelly mocking him, behavior you'll find in sociopaths. Edison had a disregard for right and wrong, was consistently dishonest, a compulsive liar, even taking credit for the Fluoroscope which killed Dally, though Tesla had been working on it before Edison irresponsibly began messing around with it. Dishonesty is a sociopathic trait. Edison stiffed Tesla a significant amount of money he owed him for fixing his DC motor, and in fact, Edison would not share any of his wealth. Edison relished being the center of attention, another sociopathic trait. I could compromise with you and say we can't know for certain that he was a sociopath. He may have merely been a narcissist, as there are a number of overlapping symptoms.

except for killing an elephant

Let that stand as a symbol for all the other horrible things Edison did, like electrocuting a number of dogs and cats, and killing his assistant.

Tesla is not exactly overrated, but at least he never stole credit for inventions, and he never killed anyone, unlike Edison (his assistant, glassblower Clarence Madison Dally, who died a rather horrible death).

"Relatively unknown," is a better description for Tesla. Edison invented a few things, the telegraph... no that was David Alter. Edison invented something to copy telegraphs, and he invented the phonograph, which was truly revolutionary, a way to record sound... but he did not invent the record player... he made lightbulbs practical... but he did not invent the electric lightbulb, of course. Edison did not invent the kinetoscope, or movie camera (that was Edward Muybridge) and he knew very little about it, but he took credit for it anyway. Edison took credit for wax paper, but he had absolutely nothing to do with that invention (invented by Gustav Le Gray). He did not invent storage batteries, but he made a lot of money with them. Edison did not invent the power generator, though he is credited for it (his assistants, Charles Batchelor and Francis Upton, were the true inventors of this).

Nearly all the other great achievements attributed to Edison were actually invented by his rival inventors or unknown (to the masses) employees, the researchers he hired, (such as the electric chair, invented by Harold P. Brown).

Tesla was a lot smarter than Edison. He never wrote anything down, and was able to keep his designs in his head. He invented the Tesla coil, the Tesla Turbine, The Shadowgraph, the Neon Lamp, The Niagra Falls Transformer House, the Induction Motor, the RC boat, Alternating Current, and Radio. Tesla held over 300 patents across 5 continents, and all of then were his innovations. God knows how many of Edison's 1000-some patents were actually his.

I don't understand how you or anyone can believe what you wrote. Edison was a major douche bag, an obvious sociopath, which sort of overshadows what he actually invented, which actually number in the low double digits. Tesla's inventions number in the low-mid triple digits

Tesla is not overrated, quite the opposite, apparently, and Edison certainly is not better in any regard than Tesla.

But Tesla was weird, and not all that popular. Edison, like all successful sociopaths throughout history, was hugely popular.

If there is one brilliant insight Einstein derived, it is that light travels at the same speed from all frames of reference. But everything else, great work was done before him, and Einstein was likely aware of it, but we forget what came before and attribute everything to Einstein.

What about Black Holes? Not so much, no. Einstein himself was pleasantly surprised to learn that the field equations, developed by Grossmann, admitted exact solutions, because of their prima facie complexity, and because he himself had only produced an approximate solution. Einstein's approximate solution was given in his famous 1915 article on the advance of the perihelion of Mercury. There, Einstein used rectangular coordinates to approximate the gravitational field around a spherically symmetric, non-rotating, non-charged mass. Karl Schwarzschild, in contrast, chose a more elegant "polar-like" coordinate system and was able to produce an exact solution which he first set down in a letter to Einstein of 22 December 1915, written while Schwarzschild was serving in the war stationed on the Russian front. Schwarzschild concluded the letter by writing: "As you see, the war treated me kindly enough, in spite of the heavy gunfire, to allow me to get away from it all and take this walk in the land of your ideas." In 1916, Einstein wrote to Schwarzschild on this result:

I have read your paper with the utmost interest. I had not expected that one could formulate the exact solution of the problem in such a simple way. I liked very much your mathematical treatment of the subject. Next Thursday I shall present the work to the Academy with a few words of explanation.—Albert Einstein

Schwarzschild's struggle with pemphigus eventually led to his death on 11 May 1916. He was only 42 years of age and at the height of his achievements when he died. Schwarzschild's work encompassed a wide range of scientific topics: he not only studied observational astronomy, but also furthered the development of astronomical instrumentation, and he was the first to give an exact solution to Einstein's (ahem, Grossmann's) field equations, which is now known as the “Schwarzschild solution."

In 1905, Albert Einstein postulated that the speed of light c with respect to any inertial frame is a constant and is independent of the motion of the light source. But he didn't just pull this rabbit out of his hat. There is a long history of science of at least the notion of the finite speed of light, and Einstein is standing on the shoulders of giants when he publishes his Special Theory of Relativity, and heavily relied on the work of three mathematicians to develop General Relativity, and a forth for his work on Black Holes. But neither Relativity nor the constancy of the speed of light were Einstein's ideas, and not remotely so. History just gave him all the credit.

He became a rock star, world renowned, and for some reason Niels Bohr gave him a lot of attention (Bohr was a the real hero scientist, sort of a manly man scientist for all seasons), but all of Einstein's decades of thought towards a GUT produced no results. After 1915, other than his plagiarism of Schwarzschild's work (following his plagiarism of David Hilbert's work), Albert Einstein did not again contribute anything to the annals of Physics or Cosmology. He became somewhat of a unfaithful husband and womanizer of his own young female students at Princeton. No judgements here. Who wouldn't have done similarly given the same opportunity? Coeds, right? They were randy for him. He had no ability to resist it.

None of these ideas are mine.

It is well-known that Einstein was notoriously bad at mathematics. The sole reason for the decade of delay between his 1905 Special Theory of Relativity and his 1915 General Theory of Relativity is that Einstein did not have the mathematics to calculate the formulas. He needed some of the work done by Hermann Minkowski. By 1908 Minkowski realized that the special theory of relativity, introduced by his former student Albert Einstein in 1905 and based on the previous work of Lorentz and Poincaré, could best be understood in a four-dimensional space, since known as the "Minkowski spacetime," in which time and space are not separated entities but intermingled in a four-dimensional space–time, and in which the Lorentz geometry of special relativity can be effectively represented using the invariant interval x^2 + y^2 + z^2 -c^2*t^2. So even the notion of space-time was not Einstein's idea. Although Einstein is credited with finding the field equations for General Relativity, the German mathematician David Hilbert published them in an article before Einstein's article. This has resulted in accusations of plagiarism against Einstein, although not from Hilbert, and assertions that the field equations should be called the "Einstein–Hilbert field equations". However, Hilbert did not press his claim for priority.

Albert Einstein's friendship with Marcel Grossmann began with their school days in Zurich. Grossmann's careful and complete lecture notes at the Federal Polytechnic School proved to be a salvation for Einstein, who missed many lectures. Grossmann's father helped Einstein get his job at the Swiss Patent Office in Bern, and it was Grossmann who helped to conduct the negotiations to bring Einstein back from Prague as a professor of physics at the Zurich Polytechnic. Grossmann was an expert in differential geometry and tensor calculus; just the mathematical tools providing a proper mathematical framework for Einstein's work on gravity. Thus, it was natural that Einstein would enter into a scientific collaboration with Grossmann.

It was mathemetician Marcel Grossmann who emphasized the importance of a non-Euclidean geometry called Riemannian geometry (also elliptic geometry) to Einstein, which was a necessary step in the development of Einstein's general theory of relativity. Abraham Pais's book on Einstein suggests that Grossmann mentored Einstein in tensor theory as well. Grossmann introduced Einstein to the absolute differential calculus, started by Christoffel and fully developed by Ricci-Curbastro and Levi-Civita. Grossmann facilitated Einstein's unique synthesis of mathematical and theoretical physics in what is still today considered the most elegant and powerful theory of gravity: the general theory of relativity. The collaboration of Einstein and Grossmann led to a ground-breaking paper: "Outline of a Generalized Theory of Relativity and of a Theory of Gravitation," which was published in 1913 and was one of the two fundamental papers which established Einstein's theory of gravity.

continues in reply to my own comment...

Empedocles (c. 490–430 BC) was the first to propose a theory of light, and claimed that light has a finite speed. In 1021, Alhazen (Ibn al-Haytham) published his Book of Optics, in which he presented a series of arguments dismissing Empedocles emission theory of vision in favour of the now accepted intromission theory, in which light moves from an object into the eye. This led Alhazen to propose that light must have a finite speed. Also in the 11th century, Ab Rayhn al-Brn agreed that light has a finite speed, and observed that the speed of light is much faster than the speed of sound. In the 13th century, Roger Bacon argued that the speed of light in air was not infinite, using philosophical arguments backed by the writing of Alhazen and Aristotle. In the 17 century, Pierre de Fermat also argued in support of a finite speed of light. In 1629, Isaac Beeckman proposed an experiment in which a person observes the flash of a cannon reflecting off a mirror about one mile (1.6 km) away. In 1638, Galileo Galilei proposed an experiment, with an apparent claim to having performed it some years earlier, to measure the speed of light by observing the delay between uncovering a lantern and its perception some distance away. He was unable to distinguish whether light travel was instantaneous or not, but concluded that if it were not, it must nevertheless be extraordinarily rapid. The first quantitative estimate of the speed of light was made in 1676 by Rømer. From the observation that the periods of Jupiter's innermost moon Io appeared to be shorter when the Earth was approaching Jupiter than when receding from it, Rømer concluded that light travels at a finite speed, and estimated that it takes light 22 minutes to cross the diameter of Earth's orbit. Christiaan Huygens combined this estimate with an estimate for the diameter of the Earth's orbit to obtain an estimate of speed of light of 220000 km/s, 26% lower than the actual value. In his 1704 book Opticks, Isaac Newton reported Rømer's calculations of the finite speed of light and gave a value of "seven or eight minutes" for the time taken for light to travel from the Sun to the Earth (the modern value is 8 minutes 19 seconds). Newton queried whether Rømer's eclipse shadows were coloured; hearing that they were not, he concluded the different colours travelled at the same speed. In 1729, James Bradley discovered stellar aberration, and from this effect he determined that light must travel 10210 times faster than the Earth in its orbit (the modern figure is 10066 times faster) or, equivalently, that it would take light 8 minutes 12 seconds to travel from the Sun to the Earth. In the 19th century Hippolyte Fizeau developed a method to determine the speed of light based on time-of-flight measurements on Earth and reported a value of 315000 km/s. His method was improved upon by Léon Foucault who obtained a value of 298000 km/s in 1862. In the year 1856, Wilhelm Eduard Weber and Rudolf Kohlrausch measured the ratio of the electromagnetic and electrostatic units of charge, 1/00, by discharging a Leyden jar, and found that its numerical value was very close to the speed of light as measured directly by Fizeau. The following year Gustav Kirchhoff calculated that an electric signal in a resistanceless wire travels along the wire at this speed. In the early 1860s, Maxwell showed that, according to the theory of electromagnetism he was working on, electromagnetic waves propagate in empty space at a speed equal to the above Weber/Kohlrausch ratio, and drawing attention to the numerical proximity of this value to the speed of light as measured by Fizeau, he proposed that light is in fact an electromagnetic wave. In 1865, James Clerk Maxwell had proposed that light was an electromagnetic wave, and therefore travelled at the speed c appearing in his theory of electromagnetism. The well-designed experiment performed by Albert A. Michelson and Edward W. Morley in 1887 failed to detect a luminiferous aether medium through which electromagnetic waves travelled. Essential to Einstein's theories, irregardless of still clinging to the notion of aether, and really because of the Michelson-Morley experiment, Hendrik Lorentz proposed that the motion of the apparatus through the aether may cause the apparatus to contract along its length in the direction of motion, and he further assumed, that the time variable for moving systems must also be changed accordingly ("local time"), which led to the formulation of the Lorentz transformation. Based on Lorentz's aether theory, Henri Poincaré (1900) showed that this local time (to first order in v/c) is indicated by clocks moving in the aether, which are synchronized under the assumption of constant light speed. In 1904, Poincaré speculated that the speed of light could be a limiting velocity in dynamics, provided that the assumptions of Lorentz's theory are all confirmed. In 1905, Poincaré brought Lorentz's aether theory into full observational agreement with the principle of relativity. To be clear, the modern origin of Relativity is rooted in Poincaré's work, and it's deeper origins first appears nearly 300 years earlier in the 1632 Galilean Invariance, aka Galileo's Theory of Relativity.

continues in reply to my own comment...

Personally, I think his work on the Photo-Electric Effect deserved the recognition that it received. But Albert Einstein is far more myth than man. Everyone idolizes Einstein, he was the quintessential mad scientist. And it is difficult to challenge the notion of this myth without being accused of anti-semetism. But I risk doing so...

When one actually studies the History of Science, one discovers shocking things. None of the ideas attributed to Einstein were actually Einstein's. I don't want to bash Einstein. He was truly brilliant. So another way to put it is Einstein stood on the shoulders of giants. Though I can and will bash the notion that Einstein was so innovative that all the ideas were his. None of them were. Let's examine all the original insights traditionally attributed to Albert Einstein. Comment too long, I will reply to my own comment and continue...

I mean no harm. But I should have just let it hang. No one cares, and this was a technical discussion, not a touchy feely one, and no one wanted the explanation. I embrace the absurd, but I should do it quietly when the adults are talking.

imagine Linus has control over it and has no clue was ZFS even is

I keep getting down voted, maybe I am too annoying for HN. But I'll risk it in the hopes this is helpful, in the social and psychological space.

First of all, I have been in awe of ZFS since... ever. But FS were not my curiosity, OS was, so I installed OpenSolaris and Illumos in VMs, a few times to get used to how these things install. No work, just play. That's me. I was sad Apple did not adopt ZFS, but they did develop a read-only something, kernel extension, I think, don't recall. And there is some support from the generous for OpenZFS on OS X (idk about macOS). Why not ZFS? Because it is different and complicated, and it takes dedication to learn. Had Apple adopted it as the native FS, I would have been forced to learn it, so that is why it made me sad. I need that kind of motivation. But many are this way to some extent. Everyone is industrious and everyone is lazy. When you can learn easily, you learn. When you must learn, you learn. When you get older, you just want to keep doing things the old way, the way you know how, and you can do that for 12+ hours a day and yet learn nothing new.

Linus is just a man. I'm glad the penguinistas have faded into the background, and I am happy for Linux, but fail to see that it was any better than NetBSD when the fanatics were vocal. Linux would have benefitted from not changing a lot of userland stuff that was changed from *NIX for no rational reason, but probably just for ignorance and arrogance. Just MHO. But now Linux is important. It just is what it is.

So Linus is insanely industrious, and also lazy just like most. How often does he learn something new, how often does he just work like a mad dog without learning anything new? Just a man, perhaps a very smart man, but no more. And he is imperfect. And I strongly suspect, by the public evidence of the tell-tale symptoms, he has an identifiable personality disorder, and it is the one that includes the symptom of an unwillingness or inability to recognize the problem. But IIRC, he did admit to things, and supposedly took time off to work on himself. But this can't be cured by the patient, though it, oddly enough, can be cured, one of the few mental illness than can be cured, not just maintained, but only after getting evaluated by a professional, and treated, and the treatment is easy, just sitting with the pro and talking twice a month for 45 minutes for up to two years. At least my understanding of it, it can be cured in two years or less depending on its severity, though rarely ever is. This is not criticism, it is compassion. Presidents get this. Captains of industry get this. Winning NFL quarterbacks get this. And it is not any surprise the Lord of the Linux kernel can get this. And I wish him the best.

We're all allowed to be incorrect and imperfect. But those that stand out get better, because they try. But as far as laziness is concerned, because I am lazy, too, and I believe most are, I can't fault anyone for being lazy and not learning new stuff, especially in order to have a better understanding of it to be able to say something about it that makes sense.

However, those that do change themselves for the better, those that are not lazy and learn new things, should be applauded, and given gratitude for the possibility that their example will be followed... hopefully by me, too.

The US and NATO has inexpensive anti-drone technology.

https://www.npr.org/2020/08/17/903152237/bald-eagle-in-michi...

https://www.youtube.com/watch?v=kAYVyj6vf3Y

Why would an F22 need to do that if the drones can't know that it is even there? Why would an f22 need to get closer than 25 miles to engage these drones? Why would an F22 ever get in a dogfight?

And I and the video creators are only claiming dark matter is not needed to explain galaxy rotation curves. Whatever other spaghetti lumped into the need for dark matter, have at it... but galaxy rotation curves are explained quite neatly looking at two things: 1) dark matter was initially postulated and never reexamined because galaxies were observed as gravitationally isolated and 2) when not unnaturally gravitationally isolating galaxies from their neighborhood group, the rotation curves make precisely exact and perfect sense