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Comment Re:Many a young engineer.... (Score 2) 82

... every schematic drawn by every semiconductor engineer got the arrow backwards.

As I heard it, The arrow is "backward" because Benjamin Franklin, when doing his work unifying "vitreous" and "resinous" electricity as surplus and deficit of a single charge carrier (and identifying the "electrical pressure" later named "voltage"), took a guess at which corresponded to a surplus of a movable charge carrier. He had a 50% chance to assign "positive" to the TYPICAL moving charge carrier in the situations being experimented with (charge transfer by friction between different substances, currents in metallic conductors, and high voltage discharges in air and water-in-air aerosols) and happened to guess "wrong".

Thus we say electrons have a negative charge, "classical current" corresponds to the sum of the flow of moving positive charge minus the flow of negative charge (i.e. the negative of the electron current, which is all there is in normal-matter metallic conductors), the arrowhead on diodes (and junction transistors) points in the direction of classical current across a junction, and so on.

But though it's the charge carrier in metallic conduction and (hard) vacuum tubes, the electron ISN'T the only charge carrier. Even in the above list of phenomena, positive ion flow is a substantial part of electrical discharge currents in air - static sparks and lightning. Positive moving charge carriers are substantial contributors to current as you get to other plasma phenomena and technologies - gas-filled "vacuum" tubes (such as thyratons), gas an LIQUID filled "vacuum" tubes (ignatrons), gas discharge lighting, arc lighting, arc welding, prototype nuclear fusion reactors, ...

Move on to electrochemistry and ALL the charge carriers are ions - atoms or molecular groups with an unequal electron and proton count, and thus a net charge - which may be either positive or negative (and you're usually working wit a mix of both).

And then there's semiconductors, where you have both electrons and "holes" participating in metallic conduction. Yes, you can argue that hole propagation is actually electron movement. But holes act like a coherent physical entity in SO many ways that it's easier to treat them as charge carriers in their own right, with their own properties, than to drill down to the electron hops that underlie them. For starters, they're the only entity in "hole current" that maintains a long-term association with the movement of a bit of charge - any given electron is only involved in a single hop, while the hole exists from its creation (by an electron being ejected from a place in the semiconductor that an electron should be, by doping or excitation, leaving a hole) to their destruction (by a free electron falling into them and releasing the energy of electron-hole-pair separation). They move around - like a charge carrier with a very short (like usually just to the next atom of the solid material) mean free path.

For me the big tell is that they participate in the Hall Effect just as if they were a positive charge carrier being deflected by a magnetic field. The hall voltage tells you the difference between the fraction of the current carried by electrons excited into a conduction band and that carried by holes - whether you think of them as actual moving positive charge carriers or a coordinated hopping phenomenon among electrons that are still in a lower energy state. Further, much of interesting semiconductor behavior is mediated by whether electrons or holes are the "majority carrier" in a given region - exactly what the hall effect tells you about it.

So, as with many engineering phenomena, the sign for charge and current is arbitrary, and there are both real and virtual current carriers with positive charge. Saying "they got it wrong" when classical current is the reverse of electron current is just metallic/thermionic conduction chauvinism. B

Comment Re:Let them lease, but not screw with sales (Score 1) 224

The real reason we see this is twofold - first, because of manufacturing and second, because of fraud.

No, you missed the third -- and most important -- reason: if the corporate oligarchy can abolish the concept of property rights (only for "consumers," of course), they can turn us all into serfs and force to rent everything from them in perpetuity.

Comment Re:Let them lease, but not screw with sales (Score 1) 224

Playing the devil's advocate... Where exactly is our "right to repair" granted? Is it in the constitution? Is it a bill signed into law?

What part of the concept of "ownership of property" do you not understand? It's been a fucking axiom of English common law since before English common law even existed!

Comment Re:Vacuum tubes handle EMP's better (Score 1) 82

"No point progressing since the bombs are gonna fall any day now. Then where will your fancy silicon highways and databases be?"

Given that the Internet Protocol and much of the rest of the networking technology that still underpins the Internet were developed as part of a cold-war program to create a communication system that could survive a nuclear attack that destroyed most of it, and still reorganize itself to pass messages quickly, efficiently, and automatically among any nodes that still had SOME path between them, your post seems to come from some alternate universe to the one I inhabit.

Comment Re:I have an idea (Score 3, Insightful) 555

If we would open drilling even more in the US and more publicly support fracking, we could never use another drop of middle eastern oil again.

Don't you dumbasses realize that we're using their oil so that when it runs out we'll still have ours left? Leaving our oil in the ground for as long as possible gives us a strategic advantage, and squandering that for short-term economic gain isn't "conservative," it's just goddamn fucking stupid!

Comment Difference between this and SpaceX (Score 1) 121

The real difference is that in order to get a payload into orbit you need enough thrust to move the fuel required to get you there. This means powerful engines. This rocket had a small engine that is capable of hovering. On an orbital class rocket your engine will have too much thrust making it impossible to hover. That is what SpaceX is trying to do. Land using a thrust to weight greater than one. This is much more difficult than a hovering landing which SpaceX has already done multiple times, along with other test craft decades ago.

Comment The IRS keeps its hooks in US citizens who leave. (Score 2) 359

I'd also move my operation to Ireland if I could.

What's stopping you?

The US tax code. The US keeps its hooks in its citizens and companies, for decades, if they try to leave, even if they move out and renounce their citizenship.

The US does this to a far greater extent than other countries who generally don't tax their citizens if they're out of the country for more than half a year. (This is where "The Jet Set" came from: Citizens of various non-US countries who had found a way to earn a living that let them split their time among three or more countries every year and avoid enough income tax to live high-on-the-hog, even on an income that otherwise might be middle-class.)

Only really big companies, with armies of lawyers, can find loopholes that let them effectively move out of the US to a lower-taxing alternative. You'll note that TFA is a lament about how one managed to escape, and how the US might "close THIS loophole" to prevent others from using it.

Comment Re:Simple Fix for H1B Visa Problem (Score 1) 55

Simply require that H-1B visa holders must be paid at least the 90th percentile (or 95th if you like) wage for their field.

Plus any amount that the employer would have to pay into a government entitlement program for a US employee that he doesn't need to pay into said program for a foreigner on H1B (or other work visa systems).

It's even fair. If the program is, say, a retirement program that the visiting worker can't benefit from, shouldn't he have the money to buy a replacement for it elsewhere?

Comment Dow makes LOTS of stuff. (Score 1) 491

... by everyone's favorite munitions manufacturer: Dow Chemical.

Dow makes a LOT of chemical stuff. Some of it's useful to the military.

If their Dow Corning partnership-subsidiary hadn't been hammered into bankruptct by a bunch of (later shown to be bogus) suits claiming medial harm from their silicon breast implants, we might have had hybrid cars a couple decades earlier, out of Detroit rather than Japan, using lenticular, glass fiber, super flywheels, rather than batteries, for energy storage.

"Help Mr. Wizard!" -- Tennessee Tuxedo