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Comment: Re:This again? (Score 1) 420

by jandersen (#49599089) Attached to: New Test Supports NASA's Controversial EM Drive

...we can violate conservation of momentum by invoking some sort of vaguely defined quantum woo

As far as I can see, Roger Shawyer is not a wild-eyed madman, but a serious engineer, who argues his case soberly. That is not to say that his claims are correct, but simply means that he actually offers something that is worth scientific scrutiny and which can be discussed and tested. On the other hand, since this is not all over the new channels, it is not something that has been demonstrated unambiguously enough yet; if this was definitely proven, then we would hear about it even in the general press.

There are two wikipedia articles:

- that seem relatively trustworthy. To me it looks like a slightly speculative concept, but one that could well have some theoretical support; I am not an expert in QM, but to my eyes it looks somewhat plausible. He doesn't claim to violate fundamental laws of physics - if he is right, and this drive works, then it uses the same phenomenon that lies behind the Casimir effect (well, read the articles, really). It doesn't generate energy from nothing, energy is expended in the process; and it doesn't work like a rocket, it seems, but like a paddle steamer, in that it sort of crawls along in the soup of quantum fluctuations (yes, I don't know what actually means either, but it sounds cool, and apparently it is an observed phenomenon, ie. real).

Comment: Re:Fluffy the feel good piece (Score 1) 70

by jandersen (#49575065) Attached to: The Next Generation of Medical Tools May Be Home-brewed

If coming up with a cheap nebulizer - which costs a hospital $2.50 for the plastic bits, is the best he can do, then this isn't going to get us far. Sure, the battery powered pump costs a couple of hundred dollars retail but anyone with more than a slotted head screwdriver for a brain is going to realize that it's an aquarium pump. This is hardly the earth shattering breakthrough that TFA insinuates it to be.

It is obvious that you find it all too easy to sneer, but the big point he is making, as far as I can see, is that a serious lot can be achieved with relatively simply means, if you have the necessary insight and a bit of creativity. Nowadays too many people are blikered into thinking that we can only ever do anything at all with high technology; one of my favourite examples of the idiocy of this sort of viewpoint comes from the simple act of shaving. Not long ago people would use a straight razor - basically a knife with a core of high-carbon steel that could keep a sharp edge. You would probably only ever buy one in your life, and you could pass it down to your son for generations. Now, however, people are sold the idea that you need a contraption with 5 very thin platinum coated blades, which you can use only a few times, and which costs something like, what, $25 for a packet of 5? Something ridiculouos, any way. And the amazing thing is - the result is not actually better, you are just being taken for a ride.

So, back to this issue: this is not about your local hospital saving money, although thigh maight well benefit as well; this is about helping poor nations achieve a better standard of health without having hundreds of billions to splurge out on luxury equipment. And who knows, it might end up saving you money on the tax or insurance bill, if your health service gets a lot cheaper. Isn't that worth doing?

Comment: Re:Makerspace.... (Score 2) 167

... a CNC vertical mill, and lathe, ...

Is that what being 'a maker' means? Who would have thought it. So it is all about spending a load on high-tech equipment and the pushing a button?

I may just be a sad, old hippie, but I think relying on heavily computerized equipment, where you can download a blueprint, push a button and out comes a finished product, that doesn't mean you're a 'maker' in my book. Yes, I know I exaggerate, but still. Or is 'maker' what you call yourself when you don't want to learn how to actually do things, you just want the finished result?

Whatever - rant's over - but I think there is a lot of real benefit to learn how to do it the primitive way, even if you later just use a machine; it gives you an insight, just like being able to write a program well in C or assembler gives you a good ballast, even if you later only write Python programs. It is sometimes quite surprising how little difference there is between using an electric tool and a manual one, if you are competent with the techniques. Just take the process of cutting a piece of plywood: it seems enticingly easy to just take an electric jigsaw and the result is guaranteed to be good, right? Except that it amazingly easy to produce a poor result. Then try the same with a handsaw - it is somewhat slower and it may be physically harder work, but it is not actually that much harder or slower, and it is in fact quite easy to do it well, if you don't try to rush it.

What I'm getting at is, don't just fall for the fallacy thinking that the only way is to set up a high-tech production facility. A very large part of the advantage of machinery is that you can produce high volumes of the same thing, but it also introduces a limitation in flexibility and will hamper your creativity. And it easily insulates you from the basic insight into what you are doing - it makes you feel helpless without your machinery.

Comment: Re:meh (Score 4, Informative) 218

by jandersen (#49563933) Attached to: JavaScript Devs: Is It Still Worth Learning jQuery?

It's a pain in the ass to read, has a nasty learning curve, and it's slow as fk

Eh? It took me all of a few days to read through one of the many reasonable books about jQuery, and I found it makes it a whole lot easier to make sense of the DOM. In a browser, what else is there to JavaScript, other than messing around with the DOM? Of course, I only use JavaScript on the client side, for the server side I use J2EE and GlassFish. jQuery is perfect for my use and very, very easy to learn.

Comment: Re:America is finished! OVER! (Score 1) 283

Look, it isn't just me saying this - it has been measured over the last 4 decades. Follow the link I provided and read about it - this guy isn't a wild-eyed prophet, but a down to earth guy who has done the foot-work. He's not asking anybody to accept it on faith, there is good data to back it up. We can all read it and make up own minds.

Comment: Re:With the best will in the world... (Score 1) 480

Of course the big question is how efficient is the process?

A quick guess: Not very. But the point here, I think, is that we are now taking it seriously enough to start doing it at any scale at all. Technology is almost always crude and inefficient in the beginning - just look at computers - but it becomes better over time - just look at computers. Of course there are many problems to overcome, but they are only problems.

Comment: Re:America is finished! OVER! (Score 1) 283

America's problem is not immigration, but the myth of trickle-down economics, which has been implemented blindly in the West. Read:

This is not about 'bleeding-heart socialism', but about why it is a good idea to maintain a balanced society, where the gap between the richest and the poorest is not too big. People only leave their home country with the culture and climate they grew up to love, when the situation becomes bad enough to make the alternatives look significantly better; modern America is the result of such migrations, so American's are well placed to understand how this works, and the America you are now mourning the loss of, was the result of these migrations.

I think you are losing the true spirit of America, because you have allowed the rich upper class to persuade you that trickle down economics will make everybody richer, and have lulled you into thinking that what they call 'democracy' is actually democracy. The solution to this problem? Well, I'm not an expert, but to me it looks like the term 'redistribution of wealth' is relevant in some form. The rich have to get less wealthy, and the poor have to get somewhat richer.

Comment: Re:Slashdot... (Score 1) 74

by jandersen (#49543907) Attached to: Apple Offers Expedited Apple Watch Order Lottery To Developers

Nothing to do with Apple. Nice try, hater.

Grow a sense of humour; or are you so insecure that anything that suggests that somebody hasn't prostrated themself in humble adulation is taken to mean that they are 'haters'? You wouldn't last long as part of an engineering team with that sort of sensitivities; we all get teased for aspects of what we do, in a friendly way - it's part of belonging. Perhaps it is way of saying "We know you understand because you are one of us".

If you want my opinion without any hint of humour, then it is like this: I think the Apple Watch is a kitchy little gadget that doesn't add much value to one's life.

- Is it an impressive, technological achievement? Well, in a modern context, not really - it is just a gadget on par with many others, and it will be dated in another year from now.

- Is it beautiful? Not to my eyes, but then I appreciate function over form, and I don't find women more sexy in high heels either, just to pick something at random.

- So, what is the point of owning an Apple Watch? Beats me, really.

Whether the Apple Watch is going to be a success remains to be seen, I think. It tries to latch on to the same instincts that has made fashion or reality TV a commercial success: the instinct to follow the crowd without having to think about anything essential. No, I'm not a neck-beard, but probably only because I have taught myself to shave with an old-fashioned straight razor, which I find is a satisfying skill.

Comment: Re:Allegedly (Score 1) 309

by jandersen (#49526857) Attached to: Futures Trader Arrested For Causing 2010 'Flash Crash'

so the crime he was committing was making money for himself instead of for Goldman Sachs.

No, the crime was that he was exploiting a weakness in the system. This is equivalent to the closed door; even if a door is locked with a flimsy lock or perhaps not locked at all - if you know that you are not allowed to go in there, you will be committing a criminal act if you enter uninvited. Or if you find a bag of cash by the road-side, or if you discover that you can get unlimited cash out of a cash-machine; if you take the money, you commit a crime. This guy knew what he was doing and that he shouldn't.

I don't have much sympathy for big finance; they too belong behind bars, for preference in a zoo.

Comment: Re:Surpirse discovery: infinity is infinite!! (Score 1) 157

by jandersen (#49511045) Attached to: Mandelbrot Zooms Now Surpass the Scale of the Observable Universe

Bigger than 28 billion light years because the universe is expanding. After the light we see now from the distant past leaves, the object that emitted it continues to move away from us.

Good point - although, what that means is only that we can, theoretically, see the objects that were, back then, going to be observable, but are now further away than the maximum distance, over which we could have received a light signal. (Wow, how about that for a mouthful of grammar?). I suppose that still qualifies as observable.

Also, thank you for not pointing out the small error of 9 orders of magnitude :-)

Disraeli was pretty close: actually, there are Lies, Damn lies, Statistics, Benchmarks, and Delivery dates.