As I said in another post, the stuff I was working with -- which might be entirely different than this -- didn't have water actually in physical contact with the face of the silicon. The die had holes in it, rather than just pads for the bond-out wires. The holes were attached to short pieces of tubing (somehow, by some magic) that served as interconnects between the die layers, so the water was only touching the inside of the stacked-up tube segments. The heat was being drawn from the die where it touched the water edge-on, and the idea relied on putting a lot of holes in the die. (That's why it was unpopular: you really don't want to waste valuable silicon on holes, which is why packages generally bond the silicon to some sort of copper leadframe, and use that to extract the heat.)
When I was working with some related stuff, the idea was that each die would have a bunch of holes in it, that would allow you to stack the dies and run coolant through the holes, while simultaneously acting as interconnects -- so ideally you could stack your L2 cache, or maybe the entire system memory, right on top of the CPU and have the whole address bus right there. Your memory would be closer than the far side of the processor die so your memory access time would be infinitesimal. Then you stack THAT whole apparatus on the top of your I/O chip. This was before we'd heard about multicore but why not just keep doing it: stack a cpu, a pile of memory, another cpu... build your own empire state building in your cpu package.
While there are still brick-and-mortar stores, there is still barter. The problem arises when amazon has displaced all the local stores and cash is simply not viable. (Turns out amazon sells chem glassware: who knew?)
At least in the area I live, most chemistry/science supply places have gone to cash-only sales because they are required to track and report ID's on check and credit card sales but not on cash sales. Interesting unintended side-effect.
Thing is -- even if they can get the machinery duplicated, down to the metal, getting the *brains* duplicated is just unbelievably difficult. We as a species have spent more man-hours on semiconductor fabrication than anything else (if I remember right) and unless a miracle happens, that's not going to be something any simple, small machine is going to be able to duplicate in the next 40 years.
The milling machine I built was babbitt-bearing for the spindle. It worked beautifully after a few hours of spinning, and it was more true than I needed. I've gotten to look at old machine shop equipment that used high-quality leather soaked in oil and tightly compressed for its headstock bearings -- and they were doing reasonable metalcutting with that kind of technology. It's possible that if the self-rep machine crowd aimed lower they'd get further.
You bring up an interesting point. Lathes and mills, like compilers, can be self-replicating. In a belt-driven machine shop, working with somewhat crude tolerances, you can make a whole new belt-driven machine shop to the same (or maybe even slightly better) tolerances. But a '30's machine shop couldn't make modern vacuum-degassed, oil-impregnated bronze bearing stock, for instance: they could only make machines that had basically the same materials they themselves were made of. Our ability to work with bulk materials has always lagged somewhat behind our ability to make specific, custom materials, in other words -- consider what I think is the highest point of materials science, directional solidification casting of turbine blades, where we have figured out how to control not only what goes in, but how the molecules structurally relate to one another in three dimensions. To build a universal 3D printer, we have to learn how to print more than just atom-by-atom: we actually have to figure out how to distort atom-by-atom printing to establish strain within materials -- and that's just to replicate things we're already building. Anyone interested in further reading on 3d printers could stand to start by reading Saul Griffith's master thesis (pdf) on the subject. I'm building a larger version of the LEGO chocolate printer he discusses/documents in there, and I've gotten a couple of jobs by explaining to crabby old machinists how I managed to cut a new, true lathe spindle on my old lathe with a bent headstock spindle. The idea of self-healing and self-replicating machines has always fascinated me.
It uses polylactic acid, which is thermoplastic, not thermosetting: the machine melts it and prints the droplet of hot material, which then freezes solid. Apparently it can also print stuff that stays somewhat flexible after printing, for softer items.
There are plenty of molten plastics that don't degas much, and there are some that are incredibly toxic. I haven't found anything about PLA yet, but I know a bit about lactic acid and it shouldn't be the health risk that, say, the stuff coming off melted polyvinyl chloride would be, or any nitrile-containing polymers. Molten nylon's not too bad, though.
Last week's New Yorker magazine has a wonderful cartoon, showing a robot covered with spiderwebs, leaning over and holding its electric cord *this* far from a power outlet. Poor emo robot...
You joke, but in the woodworking industry companies make enormously sophisticated jigs for production of wooden forms with repeating features, and at least one company has sold their jigs with EULA language specifically prohibiting using it to duplicate itself or make other jigs that allow its functionality to be duplicated, AND prohibit resale of the jig. Completely bogus, obviously, but they've gone after people with civil suits for violating the EULA and gotten settlements, I've heard. So, yeah, people are already trying to figure out how to force profitability on things that can self-replicate in a limited sense.
>Two parties perhaps but I see no daylight between them.
"I'll show you politics in America. Here it is, right here: 'I think the puppet on the right shares my beliefs.' 'I think the puppet on the left is more to my liking.' 'Hey, WAIT a minute, there's one guy holding out both puppets!'" -- Bill Hicks
Right now, according to what metric you use, somewhere between 15 and 25% of Americans don't have decent medical care because they are under- or uninsured. A larger proportion of Americans than that are going to be affected when Social Security goes belly-up (although that seems to be a manufactured crisis of sorts: it's not clear that SS would actually be going bankrupt if it were left to run on its own rather than being used as a slush fund.) By contrast, and again, depending on the metrics you use, roughly 1% of Americans are directly affected by abortion each year. (There are about 1.5M abortions per year, out of a population of about 300 million. I presume/hope both the individuals involved in makin' babies are affected by abortion.) My point is that wholly disproportionate attention is paid to that 1% -- as it is to flag-burning, gun-ownership, prayer-in-schools, and a raft of other issues -- because A: nothing is *actually* going to be done about them because of cultural inertia, so it makes the politician look to be doing something without actually having to pay for failure to succeed, and B: they're easier to get people upset about because for most people they're primarily vicarious, emotional hot topics.
By the way, I've volunteered for/worked with NARAL. I just think it's a really stupid part of the human psyche that we immediately reject otherwise good candidates based on a single issue of disagreement.
Abortion matters to the fetus in question, and to a lesser extent there's evidence that abortion has resulted in a huge decrease in crime -- and, ironically, in the number of people voting/identifying as Democrats. But to the grand scheme of things, it doesn't *matter*: my life has not been changed at all by abortion. Nor has that of most of the people I know. Even moreso gay marriage -- it's just a piece of paper. It matters to people who are arbitrarily denied tax and child custody benefits, but to society as a whole, there is no discernable effect. If the controversy vanished tomorrow, 98% of society wouldn't notice. And, most of all, that old familiar whipping-post, flag-burning, which truly Does Not Matter, but is a recurring hot button for both sides of the debate.
The things that *do* matter to people -- and are, increasingly, becoming campaign issues because we're so far behind on trying to fix them (because they're difficult) -- like the increasing number of people who lack basic health care, the increasing cost of non-negotiable expenses like food and fuel and their impact on the lowest-income members of society, the economic future of our country in the face of massive national debt and wholesale plunder of our manufacturing base: those are things that historically have been avoided like the plague by politicians because they stand to lose more than they gain by stating a position of any type. People are vastly more willing to be pissed off than to approve.
It's a feedback loop: the media tells us whatever sells the most papers/magazines, and we form our opinions based on what the media say. Marshall McLuhan and Neil Postman have both covered this extensively in their books.
There was an interesting article about this (generally) in last week's New Yorker magazine. I poorly summarize a small part: McCain's unattractiveness to the core values of the new Republican party is a symptom of some serious problems. What happens if the emotional base of the Republican party isn't in tune with how the nation is going? Where does the Republican party go, if people who are electable aren't acceptable to the core of the party?
>You would think Protestant Christians would have enough historical perspective to remember how Rome persecuted Christians and how Catholic monarchs persecuted Protestants to realize it is a fundamentally good thing to have governments which are precluded by law from expressing their religious views as part of their governance.
Thing is: if you're winning, you want to have as much power as possible to squelch anyone who competes with you. It's monopoly behavior. The people who are trying to tear down the state/religion boundaries are doing so precisely because they imagine that the resultant state religion will be THEIRS. You may ask, fairly, "but why would you think that, when history shows that again and again it doesn't work that way?" and they'll look you right in the eye and say "but God is on my side, so it *will* work." You're assuming a rationalist behavior pattern, in other words, and that's not what's at work here.
The problem is: the issues that actually matter, the ones candidates should be working on, are *hard* to fix and aren't likely to get fixed quickly. So everyone has taken to addressing issues that don't matter, that don't have any actual effect on people (like gay marriage) and offering quick fixes on those, so it looks like they're effective. We, the people, have bought into this, to the point where we now believe their stupid manufactured controversies are important.
>Though I don't know why they couldn't eventually have a mechanical-to-biological interface that duplicated the natural one non destructiveness.
That's a difficult engineering problem because it's a complicated chemical process. Nerves talk along their length by depolarization, which is essentially an electrochemical process. A nerve pumps sodium and potassium ions in opposite directions across its cell membrane to form a gradient -- think potential energy, like an anvil sitting on a table -- and when they propagate a signal along themselves, they open pores and let diffusion happen so the gradient vanishes. That signals adjacent pores to do the same thing. (A side-note: nerves are covered with something called a myelin sheath, a cell that is wrapped around like a scroll, to minimize the volume of liquid outside the nerve so it doesn't have to pump as hard to get a good gradient. Many neurodegenerative diseases, like MS, involve this sheathing cell to break down. It's not insulation, but it's sort of related.) But when nerves talk to each other, they do so across synaptic membranes, which are points where the nerves are almost in contact, separated by a narrow cleft. One nerve extrudes a bunch of bubbles of protein, filled with neurotransmitters, which diffuses across the cleft and joins/merges with the other nerve. At that point, as the bubble merges, it basically bursts, dumping all the neurotransmitters into the other nerve and starting it depolarizing in that area, which then propagates down the nerve. Neither of the processes -- depolarization or neurotransmitter diffusion -- are easily built by anything we can create. We can simulate depolarization by abusing the nerve (there is an electrical field that changes as the sodium and potassium flow back to their baseline concentrations) but that's apparently not good for the nerve in the long-term. (I may be wrong in some of the details: it's been fifteen years since I took neurobiology courses.)
I'm right-handed, mostly, but I strongly prefer to use left-hand joysticks (because I'm a pilot and am more used to flying left-hand.) I'm wondering if anyone has suggestions for good left-hand joysticks. Saitek makes ambidextrous ones that can be switched to left-hand but they wear out in about a year. Anyone have ideas or suggestions about durable leftie joysticks?
In case anyone is interested, the original research that created the idea of 'six degrees of separation' is summarized and analyzed by Malcolm Gladwell in his essay Six Degrees Of Lois Weisberg. The original research was done by Stanley Milgram (of greater fame for the (in)famous Milgram Experiment in which people were led to believe that they were shocking other people to death, but continued to do so anyway because they were Just Following Orders.) Milgram's six-degrees research, to sum up, involved handing out a large number of letters to random people, and asking them to give the letters to other people they knew who they thought would be most likely to know a (given, random, unknown-to-everyone-involved) person, and then tracking how those letters actually moved through society to their intended recipients. The result was a map that showed large groups of closely-connected people, linked by small numbers of people who were linked into many, disparate, closely-linked groups. These people are unusual and their behavior is unusually influential on others, precisely because they serve to transfer information from homogenous groups to other homogenous groups. It's not that people, or wikipedia articles, are all evenly linked by an average of six links that's important. The idea of 'six degrees of separation' is precisely about the nodes which interlink groups of nodes to each other.
Well, yes and no: it depends on your work environment. The article/question basically says that the guy has nothing to do, and since he has another job already, he has nothing to lose: he's being paid to stay at his current job for a month to answer questions if anyone else has them, and that's about it. The GPP is a harder case: where he actually has a job, of sorts. I know I'm a sort of special case, because I tend to force jobs to be what I want them to be, but my last five jobs (laser technician, silversmith, electronics technician, circuit board layout, test engineering) have all had slow times where I just didn't have enough to do, and I spent them learning how to do other, interesting, not-completely-job-related things: learning to weld steel at the silversmithing job, learning AutoCAD and programming at the laser tech job, designing equipment and learning how to program microcontrollers at the electronics jobs. I spent probably 800 hours doing those things while on the job, and because I was fulfilling my job requirements and was doing things that weren't clearly disruptive (training monkeys, learning to play the drums) nobody minded. In several cases, they ended up being vastly useful to employers, although that's not why I did them.
Since nobody else has replied directly to your question: it's unlikely. Unless you're working in commercial farming, you're most likely using a very different type of fertilizer. Until roughly 1996, fertilizer for homes was ammonium nitrate, but once Tim McVeigh demonstrated what else NH4NO3 could be used for, it was removed from consumer fertilizer and replaced with urea, H3NCONH3 (aka CON2H6 but mine gives you an idea of its structure.) These days it's quite hard to get your hands on ammonium nitrate fertilizer unless you're buying commercial quantities, where they can keep track of who you are and why you're buying it. Since urea doesn't have a nitrate group, it will react differently to this kind of detection scheme.
Well, if you want to go down THAT route: glassblowing. training cockatoos. pottery. electroetching. desktop cnc machining. building model airplanes.
All of which I've done extensively, and could do in an office, if sufficiently motivated...
Actually, our office has a rapidly expanding RC model airplane dogfighting club, and we're spending time in the lab modding and rebuilding our crashed planes, so that's halfway there -- and we're all actively employed (so far...) rather than being on in-office gardening leave.
By the way, please don't take my other response to be critical. You love programming and that's what you want to do, and that's cool. I love learning new things and I'd rather do that than anything else. They're just different ways of being. I commented because your response surprised me, and I was reminded again that not everyone else thinks the way I do. I need to keep that in mind, because it's far too easy to assume that other people are like me because then I make stupid decisions based on that.
Wow. I've been sitting here for five minutes rereading this post -- while doing other things -- and I can't get it out of my head. I can't imagine something better than being paid to read Wikipedia and learn stuff all day long for months at a time. That's basically a MacArthur grant. I'd learn Icelandic, finish my PIC data acquisition unit, re-learn synthetic organic chemistry, design and build a couple power supplies, actually learn electrical engineering rather than just pretending to know it, build a suit of chainmail, learn enough aerodynamics to design a new set of wings for a homebuilt plane... I could spend three years of 8 hour days online with ease, and love every second of it. (I know this because after a car crash I spent about six weeks bedridden and that's exactly what I did the whole time, and it was *glorious*. I learned enough Japanese to have semi-intelligent conversations and taught myself Perl during that painful vacation.)
Slashdot Mirror
As I said in another post, the stuff I was working with -- which might be entirely different than this -- didn't have water actually in physical contact with the face of the silicon. The die had holes in it, rather than just pads for the bond-out wires. The holes were attached to short pieces of tubing (somehow, by some magic) that served as interconnects between the die layers, so the water was only touching the inside of the stacked-up tube segments. The heat was being drawn from the die where it touched the water edge-on, and the idea relied on putting a lot of holes in the die. (That's why it was unpopular: you really don't want to waste valuable silicon on holes, which is why packages generally bond the silicon to some sort of copper leadframe, and use that to extract the heat.)
When I was working with some related stuff, the idea was that each die would have a bunch of holes in it, that would allow you to stack the dies and run coolant through the holes, while simultaneously acting as interconnects -- so ideally you could stack your L2 cache, or maybe the entire system memory, right on top of the CPU and have the whole address bus right there. Your memory would be closer than the far side of the processor die so your memory access time would be infinitesimal. Then you stack THAT whole apparatus on the top of your I/O chip. This was before we'd heard about multicore but why not just keep doing it: stack a cpu, a pile of memory, another cpu... build your own empire state building in your cpu package.
While there are still brick-and-mortar stores, there is still barter. The problem arises when amazon has displaced all the local stores and cash is simply not viable. (Turns out amazon sells chem glassware: who knew?)
At least in the area I live, most chemistry/science supply places have gone to cash-only sales because they are required to track and report ID's on check and credit card sales but not on cash sales. Interesting unintended side-effect.
Thing is -- even if they can get the machinery duplicated, down to the metal, getting the *brains* duplicated is just unbelievably difficult. We as a species have spent more man-hours on semiconductor fabrication than anything else (if I remember right) and unless a miracle happens, that's not going to be something any simple, small machine is going to be able to duplicate in the next 40 years.
The milling machine I built was babbitt-bearing for the spindle. It worked beautifully after a few hours of spinning, and it was more true than I needed. I've gotten to look at old machine shop equipment that used high-quality leather soaked in oil and tightly compressed for its headstock bearings -- and they were doing reasonable metalcutting with that kind of technology. It's possible that if the self-rep machine crowd aimed lower they'd get further.
You bring up an interesting point. Lathes and mills, like compilers, can be self-replicating. In a belt-driven machine shop, working with somewhat crude tolerances, you can make a whole new belt-driven machine shop to the same (or maybe even slightly better) tolerances. But a '30's machine shop couldn't make modern vacuum-degassed, oil-impregnated bronze bearing stock, for instance: they could only make machines that had basically the same materials they themselves were made of.
Our ability to work with bulk materials has always lagged somewhat behind our ability to make specific, custom materials, in other words -- consider what I think is the highest point of materials science, directional solidification casting of turbine blades, where we have figured out how to control not only what goes in, but how the molecules structurally relate to one another in three dimensions. To build a universal 3D printer, we have to learn how to print more than just atom-by-atom: we actually have to figure out how to distort atom-by-atom printing to establish strain within materials -- and that's just to replicate things we're already building.
Anyone interested in further reading on 3d printers could stand to start by reading Saul Griffith's master thesis (pdf) on the subject. I'm building a larger version of the LEGO chocolate printer he discusses/documents in there, and I've gotten a couple of jobs by explaining to crabby old machinists how I managed to cut a new, true lathe spindle on my old lathe with a bent headstock spindle. The idea of self-healing and self-replicating machines has always fascinated me.
It uses polylactic acid, which is thermoplastic, not thermosetting: the machine melts it and prints the droplet of hot material, which then freezes solid. Apparently it can also print stuff that stays somewhat flexible after printing, for softer items.
There are plenty of molten plastics that don't degas much, and there are some that are incredibly toxic. I haven't found anything about PLA yet, but I know a bit about lactic acid and it shouldn't be the health risk that, say, the stuff coming off melted polyvinyl chloride would be, or any nitrile-containing polymers. Molten nylon's not too bad, though.
Last week's New Yorker magazine has a wonderful cartoon, showing a robot covered with spiderwebs, leaning over and holding its electric cord *this* far from a power outlet. Poor emo robot...
You joke, but in the woodworking industry companies make enormously sophisticated jigs for production of wooden forms with repeating features, and at least one company has sold their jigs with EULA language specifically prohibiting using it to duplicate itself or make other jigs that allow its functionality to be duplicated, AND prohibit resale of the jig. Completely bogus, obviously, but they've gone after people with civil suits for violating the EULA and gotten settlements, I've heard.
So, yeah, people are already trying to figure out how to force profitability on things that can self-replicate in a limited sense.
>Two parties perhaps but I see no daylight between them.
"I'll show you politics in America. Here it is, right here:
'I think the puppet on the right shares my beliefs.'
'I think the puppet on the left is more to my liking.'
'Hey, WAIT a minute, there's one guy holding out both puppets!'"
-- Bill Hicks
Right now, according to what metric you use, somewhere between 15 and 25% of Americans don't have decent medical care because they are under- or uninsured. A larger proportion of Americans than that are going to be affected when Social Security goes belly-up (although that seems to be a manufactured crisis of sorts: it's not clear that SS would actually be going bankrupt if it were left to run on its own rather than being used as a slush fund.)
By contrast, and again, depending on the metrics you use, roughly 1% of Americans are directly affected by abortion each year. (There are about 1.5M abortions per year, out of a population of about 300 million. I presume/hope both the individuals involved in makin' babies are affected by abortion.)
My point is that wholly disproportionate attention is paid to that 1% -- as it is to flag-burning, gun-ownership, prayer-in-schools, and a raft of other issues -- because A: nothing is *actually* going to be done about them because of cultural inertia, so it makes the politician look to be doing something without actually having to pay for failure to succeed, and B: they're easier to get people upset about because for most people they're primarily vicarious, emotional hot topics.
By the way, I've volunteered for/worked with NARAL. I just think it's a really stupid part of the human psyche that we immediately reject otherwise good candidates based on a single issue of disagreement.
Abortion matters to the fetus in question, and to a lesser extent there's evidence that abortion has resulted in a huge decrease in crime -- and, ironically, in the number of people voting/identifying as Democrats. But to the grand scheme of things, it doesn't *matter*: my life has not been changed at all by abortion. Nor has that of most of the people I know.
Even moreso gay marriage -- it's just a piece of paper. It matters to people who are arbitrarily denied tax and child custody benefits, but to society as a whole, there is no discernable effect. If the controversy vanished tomorrow, 98% of society wouldn't notice.
And, most of all, that old familiar whipping-post, flag-burning, which truly Does Not Matter, but is a recurring hot button for both sides of the debate.
The things that *do* matter to people -- and are, increasingly, becoming campaign issues because we're so far behind on trying to fix them (because they're difficult) -- like the increasing number of people who lack basic health care, the increasing cost of non-negotiable expenses like food and fuel and their impact on the lowest-income members of society, the economic future of our country in the face of massive national debt and wholesale plunder of our manufacturing base: those are things that historically have been avoided like the plague by politicians because they stand to lose more than they gain by stating a position of any type. People are vastly more willing to be pissed off than to approve.
It's a feedback loop: the media tells us whatever sells the most papers/magazines, and we form our opinions based on what the media say. Marshall McLuhan and Neil Postman have both covered this extensively in their books.
There was an interesting article about this (generally) in last week's New Yorker magazine. I poorly summarize a small part: McCain's unattractiveness to the core values of the new Republican party is a symptom of some serious problems. What happens if the emotional base of the Republican party isn't in tune with how the nation is going? Where does the Republican party go, if people who are electable aren't acceptable to the core of the party?
>You would think Protestant Christians would have enough historical perspective to remember how Rome persecuted Christians and how Catholic monarchs persecuted Protestants to realize it is a fundamentally good thing to have governments which are precluded by law from expressing their religious views as part of their governance.
Thing is: if you're winning, you want to have as much power as possible to squelch anyone who competes with you. It's monopoly behavior. The people who are trying to tear down the state/religion boundaries are doing so precisely because they imagine that the resultant state religion will be THEIRS. You may ask, fairly, "but why would you think that, when history shows that again and again it doesn't work that way?" and they'll look you right in the eye and say "but God is on my side, so it *will* work."
You're assuming a rationalist behavior pattern, in other words, and that's not what's at work here.
The problem is: the issues that actually matter, the ones candidates should be working on, are *hard* to fix and aren't likely to get fixed quickly.
So everyone has taken to addressing issues that don't matter, that don't have any actual effect on people (like gay marriage) and offering quick fixes on those, so it looks like they're effective.
We, the people, have bought into this, to the point where we now believe their stupid manufactured controversies are important.
>Though I don't know why they couldn't eventually have a mechanical-to-biological interface that duplicated the natural one non destructiveness.
That's a difficult engineering problem because it's a complicated chemical process. Nerves talk along their length by depolarization, which is essentially an electrochemical process. A nerve pumps sodium and potassium ions in opposite directions across its cell membrane to form a gradient -- think potential energy, like an anvil sitting on a table -- and when they propagate a signal along themselves, they open pores and let diffusion happen so the gradient vanishes. That signals adjacent pores to do the same thing. (A side-note: nerves are covered with something called a myelin sheath, a cell that is wrapped around like a scroll, to minimize the volume of liquid outside the nerve so it doesn't have to pump as hard to get a good gradient. Many neurodegenerative diseases, like MS, involve this sheathing cell to break down. It's not insulation, but it's sort of related.)
But when nerves talk to each other, they do so across synaptic membranes, which are points where the nerves are almost in contact, separated by a narrow cleft. One nerve extrudes a bunch of bubbles of protein, filled with neurotransmitters, which diffuses across the cleft and joins/merges with the other nerve. At that point, as the bubble merges, it basically bursts, dumping all the neurotransmitters into the other nerve and starting it depolarizing in that area, which then propagates down the nerve.
Neither of the processes -- depolarization or neurotransmitter diffusion -- are easily built by anything we can create. We can simulate depolarization by abusing the nerve (there is an electrical field that changes as the sodium and potassium flow back to their baseline concentrations) but that's apparently not good for the nerve in the long-term.
(I may be wrong in some of the details: it's been fifteen years since I took neurobiology courses.)
I'm right-handed, mostly, but I strongly prefer to use left-hand joysticks (because I'm a pilot and am more used to flying left-hand.)
I'm wondering if anyone has suggestions for good left-hand joysticks.
Saitek makes ambidextrous ones that can be switched to left-hand but they wear out in about a year.
Anyone have ideas or suggestions about durable leftie joysticks?
In case anyone is interested, the original research that created the idea of 'six degrees of separation' is summarized and analyzed by Malcolm Gladwell in his essay Six Degrees Of Lois Weisberg. The original research was done by Stanley Milgram (of greater fame for the (in)famous Milgram Experiment in which people were led to believe that they were shocking other people to death, but continued to do so anyway because they were Just Following Orders.) Milgram's six-degrees research, to sum up, involved handing out a large number of letters to random people, and asking them to give the letters to other people they knew who they thought would be most likely to know a (given, random, unknown-to-everyone-involved) person, and then tracking how those letters actually moved through society to their intended recipients.
The result was a map that showed large groups of closely-connected people, linked by small numbers of people who were linked into many, disparate, closely-linked groups. These people are unusual and their behavior is unusually influential on others, precisely because they serve to transfer information from homogenous groups to other homogenous groups.
It's not that people, or wikipedia articles, are all evenly linked by an average of six links that's important. The idea of 'six degrees of separation' is precisely about the nodes which interlink groups of nodes to each other.
One of these days, the MPAA is going to cut this program into little pieces...
Well, yes and no: it depends on your work environment. The article/question basically says that the guy has nothing to do, and since he has another job already, he has nothing to lose: he's being paid to stay at his current job for a month to answer questions if anyone else has them, and that's about it. The GPP is a harder case: where he actually has a job, of sorts.
I know I'm a sort of special case, because I tend to force jobs to be what I want them to be, but my last five jobs (laser technician, silversmith, electronics technician, circuit board layout, test engineering) have all had slow times where I just didn't have enough to do, and I spent them learning how to do other, interesting, not-completely-job-related things: learning to weld steel at the silversmithing job, learning AutoCAD and programming at the laser tech job, designing equipment and learning how to program microcontrollers at the electronics jobs. I spent probably 800 hours doing those things while on the job, and because I was fulfilling my job requirements and was doing things that weren't clearly disruptive (training monkeys, learning to play the drums) nobody minded. In several cases, they ended up being vastly useful to employers, although that's not why I did them.
Since nobody else has replied directly to your question: it's unlikely. Unless you're working in commercial farming, you're most likely using a very different type of fertilizer. Until roughly 1996, fertilizer for homes was ammonium nitrate, but once Tim McVeigh demonstrated what else NH4NO3 could be used for, it was removed from consumer fertilizer and replaced with urea, H3NCONH3 (aka CON2H6 but mine gives you an idea of its structure.) These days it's quite hard to get your hands on ammonium nitrate fertilizer unless you're buying commercial quantities, where they can keep track of who you are and why you're buying it.
Since urea doesn't have a nitrate group, it will react differently to this kind of detection scheme.
Well, if you want to go down THAT route:
glassblowing.
training cockatoos.
pottery.
electroetching.
desktop cnc machining.
building model airplanes.
All of which I've done extensively, and could do in an office, if sufficiently motivated...
Actually, our office has a rapidly expanding RC model airplane dogfighting club, and we're spending time in the lab modding and rebuilding our crashed planes, so that's halfway there -- and we're all actively employed (so far...) rather than being on in-office gardening leave.
By the way, please don't take my other response to be critical. You love programming and that's what you want to do, and that's cool. I love learning new things and I'd rather do that than anything else. They're just different ways of being. I commented because your response surprised me, and I was reminded again that not everyone else thinks the way I do. I need to keep that in mind, because it's far too easy to assume that other people are like me because then I make stupid decisions based on that.
Wow. I've been sitting here for five minutes rereading this post -- while doing other things -- and I can't get it out of my head.
I can't imagine something better than being paid to read Wikipedia and learn stuff all day long for months at a time. That's basically a MacArthur grant.
I'd learn Icelandic, finish my PIC data acquisition unit, re-learn synthetic organic chemistry, design and build a couple power supplies, actually learn electrical engineering rather than just pretending to know it, build a suit of chainmail, learn enough aerodynamics to design a new set of wings for a homebuilt plane... I could spend three years of 8 hour days online with ease, and love every second of it.
(I know this because after a car crash I spent about six weeks bedridden and that's exactly what I did the whole time, and it was *glorious*. I learned enough Japanese to have semi-intelligent conversations and taught myself Perl during that painful vacation.)