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Comment Conservation of Momentum (Score 3, Insightful) 470

If you're going to have reaction drive style thrusters for maneuvering, you're going to run out of fuel very quickly, dissipating mass, unless your thrusters are thrusting out little bits of mass at VERY high speed, in which case they could be used as weapons themselves. (Sci Fi writer Larry Niven came up with the idea of a reaction drive as a weapon, google the 'Kzinti Lesson' for more info.)

I think it would be interesting to have space battles where several fighters were somehow connected to each other via some sort of tractor beam, so they maneuvered by transferring momentum between each other instead of dissipating mass into the vastness of space; they might look a bit like bolas circling each other but with quick changes snapping in and out as they went in to battle, or maybe they would be tethered to a mother ship, somewhat like World War II aircraft carrier that sends out figher planes to do the fighting. The mother ship would have enough mass to let the fighters seem to be free to zap around easily.

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("Cough Cough") I wrote an unpublished Sci Fi Novel (I did send it to a bunch of publishers at the time, over 10 years ago), where interstellar travel used 'draggers'. There was no faster than light travel so it took years and years to go between even nearby stars, (The travelers themselves would be in an accelerated frame of reference so it wouldn't be so long for them.) In the novel it took a long time to set up a system between two solar systems, similar to the way it takes a long time to set up a railway between two cities, but then you could use it very efficiently. A vessel would attach itself to a dragger, and be quickly accelerated (that's the hard part, dealing with the sudden accleration that would flatten everything against the back wall like you were in a super cream separator), the dragger, much more massive than the vessel, would be slowed down some, but then, at the other end, as the dragger wheeled around a star, the vessel would transfer it's momentum back to the dragger and slow down to become part of the other solar system.

The thing about conservation of momentum is that it means the center of mass of a closed system doesn't change. If two solar systems and the draggers going between them were a closed system, then the center of mass would shift as the vessel moved between one and the other, but, if the vessel returned to the original system again, then the original center of mass would be restored, and the energy used to move between them could be recycled, plus there wouldn't be reaction mass being spewed out all over the place.

Comment Is it healthy or unhealthy for society to have ... (Score 2) 275

I'm just wondering if when a society has conspiracy theorists speaking out freely, the 'tin hat' crowd, is that the sign of a healthy society or not.

It's bad I suppose when conspiracy theorists are flat out wrong, but would a repressive government try to silence them or do repressive governments only bother suppressing people who are telling the Truth?

Does it do harm in that when somebody really finds something bad going on people will tend to disbelieve them because of all the flakos (sort of like crying wolf too many times)?

Is there some sort of bell shaped curve of attitude towards what the establishment tells us in that a few people on one end of the curve will believe everything and bury their heads in the sand over any problem (like maybe global warming), and a few on the other end of the curve will leap at anything as a plot, while most people are somewhere in the middle? If there is such a curve, maybe it's characteristics (skew, standard deviation, etc) are what determine the 'health' of the society.

Comment Re:Er? (automatic locale?) (Score 1) 314

Hmmm, it sounds like what's needed is a daemon that queries location from a GPS system as well as time, and automatically adjusts timezone and whatever (would you want it to change language? Seems like that's more of a user thing, and something you only change when you change users). Of course, it would require the system be hooked up to a GPS system, otherwise do things the old-fashioned manual way. There could be an app that puts up a map where you click on the location I suppose, instead of fiddling with configuration files.

I'm an old time unix user (going back to 4.2 BSD days). I like the idea of text configuration files for everything. But I wouldn't mind a front end app that was easier to use than constantly having to look at man pages on the formats of everything. A sort of IDE for all the text based config files the way an IDE is a helper for the text code files of a programming language. (But NOT a binary that bypasses the text configs! Which is what systemd seems to be doing, if I've been reading this right.)

Comment Re:Why attack Java like this? (Score 2) 94

Isn't Python supposed to have suffered from a big revision change? My first thought, when I read about Dr Odersky making revisions is that he would be running into the same problem that Python did. Maybe Scala isn't as widely adopted yet as Pascal was, and he thinks he should fix it now before there would be too big of a flap over it. (Actually, if they're changing Java as I gather they are from the interview, wouldn't that also be a blowback for Java?)

I'm an old timer who has never used any of these new-fangled languages professionally (where new-fangled is anything newer then C), so I'm not trying to editorialize here, just wondering.

Comment Re:It's a question that WAS relevant (Score 1) 161

Back in the 1970s I worked at a computer manufacturer, writing code for their product's instruction set in assembler. The computers were designed and built around AMD2901 bit slices. The hardware guys implemented the instruction sets using microcode and, as the computers got bigger and more complicated some of the instructions got so elaborate that programmers found ways to do an operation faster using a few simpler instructions instead of one complicated one.

Nowadays, with the kind of speedups from using cache memory, branch prediction, and so on, I reckon it could be a whole different ballgame. I suspect though, that proving correctness might become the most important criteria, and simpler would make proving correctness easier.

Comment Re:Is the complexity of C++ job security? (Score 1) 427

I'm not a C++ programmer. But I have come across situations where people seemed to deliberately use weird, obfuscating stuff just so nobody else could take their place, (I particularly remember a company where somebody had convinced management to use UUCP instead of FTP for internal data xfers because it was more secure. When I was being interviewed on the phone they asked me what I thought of UUCP, and I think I was one of the few people they interviewed who had even heard of it.)

So, if C++ is as complicated and full of stuff as I keep reading about, I can see how somebody might deliberately cultivate for themselves a set of esoteric off the wall constructions that they'd throw in their code just so nobody else could work with it, all the time selling management on how 'good' it was.

Comment Re:Is the complexity of C++ a practical joke? (Score 1, Troll) 427

"Life is a learning experience, so break out the reference manuals"
That's fine if you're a student. I've been in situations where I was working for a small company and I had to fix problems for the company quickly so they could bill their client and make payroll. If C++ is supposed to be a bunch of languages rolled in to one, then, the code should be flagged, "This is C++ as a functional language, only people who know all the functional stuff should use it, or be hired to maintain it in the future, and don't stick in anything of exotic flavors X, Y, or Z from C++ in it". Or, if the company was serious about doing the product in a functional way, one could use Haskell or Scheme or whatever in the first place."

Comment Re:Premise flawed? (Score 2) 116

NOW, after my moderator points have expired, somebody posts something I would want to mod up!

From my own experience, when I had really difficult, gnarly problems, the code came out really clean at the end. The bugs came when I was least expecting them with stuff that should have been a piece of cake.

I think it might be a bit like what somebody once told me about private airplane pilots. Statistically, accidents didn't happen the most when people were novices, but after a certain number of flight hours. I don't remember exactly what they were. Actually there were 2 peaks, for the sake of argument I'll say that one was at 2000 hours and one at 8000 hours flight time. An interesting phenomenon.

Comment Re:You're welcome to them. A few words re Emacs (Score 1) 402

Hear Hear,
I generally use vi myself, though I've actually forgotten some of the fancier stuff. I even have some muscle memory for emacs which I acquired because I had an Atari 500 ST back in the 1980s. Having cut my teeth on old glass teletypes (Uniscopes, Hazeltines, and even genuine VT-100s with the gold keys pad) I needed a basic term window and text editor for my Atari. The best text editor for the Atari that I could find on Usenet in the old binaries groups was 'Micro-Emacs', a very stripped down version of emacs, but in using it, my fingers learned CTR-E to go to the end of a line, CTRL X 2 to split a screen, etc. It's because of that that I still use emacs sometimes for very basic stuff. (I always install the -nox version). Heh, back in the 80s, I knew if I was on a fast computer at work if I could use emacs and it was responsive, which made Micro-Emacs, running on my Atari so well, all that much more impressive.

Comment Re:Ummm (Score 2) 347

Ah, this is getting off topic, but your comment raised a question in my mind. Suppose the light is blue shifted for an observer approaching it so that it does have the energy to form an electron-positron pair, but for another observer not approaching it as fast, it doesn't have the energy. Might one observer see the pair formation while the other did not?

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