Another lousy and expensive solution looking for a problem.
This kind of thingy is somewhat less useful and accurate than a "ruler" in the picture:
You have to calibrate the laser dot spacing against a ruler anyway, so you don't save the cost or weight of carrying around a ruler.
The calibration is only good at ONE distance and perpendicular to the lasers.
Rulers and tape measures can be used to measure other things, that lasers can't- like skew distances, or circumferences.
Rulers always show up as the right brightness on a photograph. Lasers have to be adjusted in brightness to match the scene, and may wash out if a flash is used.
Red laser light is not too visible if the object is like, red, or covered with blood.
Don't go put all your money on this company.. oh wait...
There's really nothing nano-dependent in this idea.
Cell phones around here use the 800MHz part of the spectrum. Around that range, radio waves are about 1 foot long. To stop those waves from penetrating you need something on the order of mosquito-screening.
You don't need nano-particles.
The only reason nano-tech is in this fine article is the clay quarry this guy owns happens to have clay particles that small.
Um, the code can't change all that frequently, as the key fob is in your pocket at 98.6 degrees F, and the one on the door can, here in the cold country, be at -40 degrees F or C. With the typical temperature coefficient of a crystal clock, they can't have the time intervals be too short. Also due to fencepost error, they have to allow at lkeast one code's worth of past code slop just in case the door code has just flipped but the fob one is a few seconds behind.
So as a rough guess, you have several minutes during which at least three codes will work, maybe more.
Everytime somebody writes some VBA or Excel macro code, another consultant gets a BMW.
All you GOOD programmers out there-- think back to the first year of programs you wrote back when you were not much more than an average Joe. >
For all the Joe's out there: Anybody can carve a steak, but that doesnt make you a brain surgeon. Anybody can write one or two lines of code. But somewhere around 4 lines, things start to break or act funny if you don't know exactly what you're doing.
orbital mechanics-- BONK! ??
on
Golf in Space
·
· Score: 1
I'm a little weak on orbital mechanics, but please see though my reasoning:
If you just let go of a golfball in space, it's going to, in the short run, stay put.
If you give it a very light push, it's going to orbit around the ISS, coming back to the launching point on each revolution.
If you slam it with a golf club, faster than escape velocity from the ISS, it's going to take off on an orbit around the Earth, again coming back to the same launch point at each revolution? Is this right?
Ahem, it's not a free server, if you read the fine print.
You get a LOANER server. At the end of 30 days, you have the option of buying it, or mailing it back, insured, at your expense, or taking the chance they like your bribed-for review. For 99% of the people that read Slashdot, that means you're out $60 bucks. That's a *long* way from getting a free server.
The Tek 585A scope, from circa 1962, is about 95% vacuum toobs, but it has a tunnel diode in its triggering circuit.
According to classical physics, and the kind of reasoning in The Fine Article, the input signal can never get through the diode. According to quantum physics, the signal CAN get through even though there's an (classically) insurmountable hill.
Using the same logic as The Fine Article, this old scope displays waveforms without a signal ever getting through the sweep triggering circuit.
Super! Attention Japanese folks: I will take off your hands any old Nakamichi Dragons (OP: $5600), no charge for displsal. Same deal for any Amiritsu spectrum analyzers (>$4000 each). No charge.
What really worris me is a university president that is ignorant of basic physics and math. Let's do a back-of-the-web-page calculation:
Assume: Sunlight is electromagnetic radiation too.
Full sunshine hits you with about 1000 watts per square meter.
Assume: Your body has one square meter of frontal surface area (John Belushi, not Kate Moss).
So on a sunny day you're getting hit with 1000 watts of electromagnetic radiation, heating you up considerably. Much as if you were in a restaurant-strength microwave oven.
Assume: I'm too lazy to look up the exact power, so let's assume a Wi-Fi antenna puts out one whole watt (greatly exaggerated).
Also assume you're standing three feet from the antenna.
A rough guess: your body is going to intercept about 1/40th of the emitted radiation.
So we have on the one hand, sunlight at 1000 watts, and wi-fi at 1/40th of a watt, a difference in intensity of 25,000 times.
And while exposure to sunlight for like 10 years will eventually cause wrinkles and skin cancer, very few students or staff stay in school for the proportionally requisite 250,000 years, three feet from a hot-spot antenna.
You don't need that much hardware to defeat MacroVision. Two diodes, three resistors, three capacitors, two cheap IC's. One comparator to extract the sync, another to gate out the leading pulse, a 4040 counter to count up to line 255, anoher comparator to gate out the trailing pulse. ALmost a no-brainer.
Nope. That trick works fine if you're sending 10^10 or more photons per second. A few won't be missed.
Doesnt work at all if you're sending ONE photon at a time.
The difference in conductivity between copper and silver is miniscule. 1.58 versus 1.68. That's 1 part in 16. According to Moore's "Law", that gives you a month and six days of breathing room.
And it's heartwarming to see such undiluted faith in nanotubes. Some might have doubts, as nobody's yet intentionally made even a millimeter of ballistic nanotube at any price, whilst a CPU chip would need quite a stretch of them, all perfect, for under $5.
What I was trying to convey was the that the simplistic original article didnt even begin to convey the scope and depth of the challenges. Just being able to draw narrower lines isn't the be-all and end-all. If not several cans of whup-ass, at least one of worms.
Just being able to make thinner lines is not that huge a deal.
There's several large cans of whup-ass that have to be overcome before you can make IC's that much smaller:
Lines are 2-D thingies, but conductors are 3-D. Your etching technology has to get X times better to keep up with the line-drawing technology.
Same thing with the active components. If you try making the transistor half the old linear dimensions, you have 1/8th the volume of active silicon. This leads to all kinds of problems with leakage and power handling capability.
A line that's half as wide and half as thick has four times the resistance per unit length, and 1/4 the current-carrying capacity. You can try using a better conductor, but once you get to using copper, you're done.
And the programmers will just soak up all your extra speed by turning up the "ooooh" factor (See: Vista).
Ahem, the authors may know a lot about quantum stuff, but they don't know anything about how fiber optics work.
If somebody is tapping the line, strongly enough to intercept photons, it's easily determined by using a TDR (time-domain reflectometer)-- basically optical radar. Even a 1% discontinuity in amplitude or length can be detected. All it takes is a little handheld gadget.
AND if they're tapping and resending the signal, it's lost all its entangled properties, so the other end won't get the right combination os states, proof there's tapping going on.
Solving differential equations numerically means basically a lot of multiplying and adding. So the IBM machines could and DID evaluate differential equations and integrals. A bit more slowly than ENIAC, but still doing the job.
Well, there goes the Earth! Killed by a do-gooder. Let me explain.
There's this thing called "efficiency" and this other thing: "economies of scale". Not to mention "closed cycles" and "ignoring important issues".
People in the power business have been thinking about these issues for many decades now. Lone inventors hardly ever do.
If you want to get a kilowatt of electricity, here's two ways:
(1) Put a kilo of dried cow dung into a small Stirling engine/generator. You'll get a kilowatt for X minutes per cow flop.
(2) Put a kilo of dried cow dung into a large heat engine/generator, preferably anything but a Stirling. You'll get a kilowatt for X*Y minutes per cow flop. Where Y is the increased efficiency of a good heat engine.
The value of Y is arguable, but probably between 2 and 20. Stirling engines are not noted for their efficiency. To say the very least.
Looked at another way, the Stirling engine is going to require 2 to 20 times more cow flops, not to mention operating staff, people or vehicles to bring in cow flops from the surrounding area, etc.
That's why we don't already do this in the developed areas, it's not cost efficient to have anything smaller than a HUGE, well-designed, well-maintained, pollution-controlled generating station. HUGE as in many megawatts, enough for a whole village.
And there's the whole issue of cow flops. You and I probably think they cost nothing. Wrongo. They're already being used for cooking fuel and heating fuel. Every cow-flop that goes into a Stirling engine is one less cow-flop for cooking dinner. The fuel is *not* free. Same with other energy sources-- they're already being used way beyond the sustainable level. There are places where women already walk 30 km a day just to get firewood to cook dinner. We don't need another inefficient drain on scarce resources.
This backyard-burner thing is just going to deforest and pollute and smell up the world. No thanks.
Yes, there are theoretical quantum numbers that describe an electron. But you can't measure any of them without destroying the property. And they're not at any one particular value for more than an attosecond. And you can't match up properties with individual electrons, because there are no extra dimensions of freedom to tag electrons with.
In computer lingo, for a viable memory, you need to have address:value pairs, but with electrons, there are no addresses, and no stable values either. Kinda totally skunked from the get-go.
Way back in the mists of time, the same thing was going on. Popular magazines in the 1930's were saying "Television is coming". Radio sales started dropping off as people were expecting to buy a TV any day now.
Then some marketing genius figured out they could put a 15 cent audio input jack on the back of a radio and then sell the radio as "TV READY". The gist being that your radio wouldnt be obsolete when TV arrived-- you'd pipe the TV audio out through your radio speakers.
Of course when TV's did come out they all had built-in speakers, so nobody ever used this feature, but, yes, the radios were "TV Ready".
This article is pure balderdash. Even lowly me, with just one semester of quantum mechanics can see it's all pure hokum. Ah, for the days when you could get past the first sentence without realizing it was all fairy dust!
The basic problem is: you can't identify individual electrons. No way. Not ever. When they're circling an atom they're not discernible particles per se- they're an anonymous and homogenous cloud of probability. You can apply some energy and peel one electron off, but it's not like you're picking a particular electron. It's not like a bag of marbles and you're picking a particular one of a particular color. It's more like a jar of molasses and you're scooping out a spoonful.
Also electron spin isnt something that's latched to any one electron. Electrons exchange virtual photons many millions of million of times per second, which scrambles their properties.
So to beat this dead horse again: there's absolutely nothing to this story.
>It was a program to calculate the first 1000 digits of Pi.
Seems Unlikely
The ENIAC had only 20 registers, holding 10 decimal digits each.
Kinda hard to generate 1000 digits with only 200 digits of storage.
There are algorithms that generate sequential digits of Pi, but I doubt if they were well known at that time.
>They had a process by which you had to review any functions that were going into the computer before you put them in...
Well, of course, because it took a lot of time and work to rewire the computer to run a new algorithm.
And people were worth $2 an hour, while the computer probably was worth $100 an hour or more.
>Expensive but extremely effective at reducing software bugs in code...
I doubt if the early programmers were any better at finding bugs ahead of time than we are. They had the added complications of having to take into acount propagation delay and the many hardware glitches of each module.
>The only time the machine was down was for tubes and hardware.
Er, No, it had to go down completely for reprogramming.
Three Hundred Fifty Milliwatts is 0.35 of one Watt. Most lasers are under 50% efficient. The deflection and modulation and optics are unlikely to be more than 50% efficient.
So imagine spreading 0.090 watts of light over a screen-sized area. Pretty dang dim! Like you'll need dark adapted eyes to even see the picture.
Still a neat device, but you're not going to run your own Drive-in movie theater with it.
Fenynman used these at Los Alamos in 1944 to compute critical massses of Plutonium.
And these were programmable, to an extent, with plugboards, which incidentally was more flexible that the ENIAC arrangment of plugs and cables. You could swap plugboards in 5 seconds; reconfiguring ENIAC for a new program could take many many hours.
Eventually ENIAC was re-architected to take instructions from a huge bank of switches, before that it was program by plug.
Slashdot Mirror
This kind of thingy is somewhat less useful and accurate than a "ruler" in the picture:
- You have to calibrate the laser dot spacing against a ruler anyway, so you don't save the cost or weight of carrying around a ruler.
- The calibration is only good at ONE distance and perpendicular to the lasers.
- Rulers and tape measures can be used to measure other things, that lasers can't- like skew distances, or circumferences.
- Rulers always show up as the right brightness on a photograph. Lasers have to be adjusted in brightness to match the scene, and may wash out if a flash is used.
- Red laser light is not too visible if the object is like, red, or covered with blood.
Don't go put all your money on this company.. oh wait...There's really nothing nano-dependent in this idea.
Cell phones around here use the 800MHz part of the spectrum. Around that range, radio waves are about 1 foot long. To stop those waves from penetrating you need something on the order of mosquito-screening.
You don't need nano-particles.
The only reason nano-tech is in this fine article is the clay quarry this guy owns happens to have clay particles that small.
Sign, Yet another ridiculous nano-article.
So as a rough guess, you have several minutes during which at least three codes will work, maybe more.
Everytime somebody writes some VBA or Excel macro code, another consultant gets a BMW.
All you GOOD programmers out there-- think back to the first year of programs you wrote back when you were not much more than an average Joe. >
For all the Joe's out there: Anybody can carve a steak, but that doesnt make you a brain surgeon. Anybody can write one or two lines of code. But somewhere around 4 lines, things start to break or act funny if you don't know exactly what you're doing.
A postulated swarm of thousands (why not millions?) of:
You get a LOANER server. At the end of 30 days, you have the option of buying it, or mailing it back, insured, at your expense, or taking the chance they like your bribed-for review. For 99% of the people that read Slashdot, that means you're out $60 bucks. That's a *long* way from getting a free server.
The Tek 585A scope, from circa 1962, is about 95% vacuum toobs, but it has a tunnel diode in its triggering circuit. According to classical physics, and the kind of reasoning in The Fine Article, the input signal can never get through the diode. According to quantum physics, the signal CAN get through even though there's an (classically) insurmountable hill. Using the same logic as The Fine Article, this old scope displays waveforms without a signal ever getting through the sweep triggering circuit.
Super! Attention Japanese folks: I will take off your hands any old Nakamichi Dragons (OP: $5600), no charge for displsal. Same deal for any Amiritsu spectrum analyzers (>$4000 each). No charge.
Assume: Sunlight is electromagnetic radiation too.
Full sunshine hits you with about 1000 watts per square meter.
Assume: Your body has one square meter of frontal surface area (John Belushi, not Kate Moss).
So on a sunny day you're getting hit with 1000 watts of electromagnetic radiation, heating you up considerably. Much as if you were in a restaurant-strength microwave oven.
Assume: I'm too lazy to look up the exact power, so let's assume a Wi-Fi antenna puts out one whole watt (greatly exaggerated).
Also assume you're standing three feet from the antenna.
A rough guess: your body is going to intercept about 1/40th of the emitted radiation.
So we have on the one hand, sunlight at 1000 watts, and wi-fi at 1/40th of a watt, a difference in intensity of 25,000 times.
And while exposure to sunlight for like 10 years will eventually cause wrinkles and skin cancer, very few students or staff stay in school for the proportionally requisite 250,000 years, three feet from a hot-spot antenna.
More likely you'll die of terminal boredom.
You don't need that much hardware to defeat MacroVision. Two diodes, three resistors, three capacitors, two cheap IC's. One comparator to extract the sync, another to gate out the leading pulse, a 4040 counter to count up to line 255, anoher comparator to gate out the trailing pulse. ALmost a no-brainer.
Nope. That trick works fine if you're sending 10^10 or more photons per second. A few won't be missed. Doesnt work at all if you're sending ONE photon at a time.
The difference in conductivity between copper and silver is miniscule. 1.58 versus 1.68. That's 1 part in 16. According to Moore's "Law", that gives you a month and six days of breathing room.
And it's heartwarming to see such undiluted faith in nanotubes. Some might have doubts, as nobody's yet intentionally made even a millimeter of ballistic nanotube at any price, whilst a CPU chip would need quite a stretch of them, all perfect, for under $5.
What I was trying to convey was the that the simplistic original article didnt even begin to convey the scope and depth of the challenges. Just being able to draw narrower lines isn't the be-all and end-all. If not several cans of whup-ass, at least one of worms.
There's several large cans of whup-ass that have to be overcome before you can make IC's that much smaller:
And the programmers will just soak up all your extra speed by turning up the "ooooh" factor (See: Vista).
If somebody is tapping the line, strongly enough to intercept photons, it's easily determined by using a TDR (time-domain reflectometer)-- basically optical radar. Even a 1% discontinuity in amplitude or length can be detected. All it takes is a little handheld gadget.
AND if they're tapping and resending the signal, it's lost all its entangled properties, so the other end won't get the right combination os states, proof there's tapping going on.
Solving differential equations numerically means basically a lot of multiplying and adding. So the IBM machines could and DID evaluate differential equations and integrals. A bit more slowly than ENIAC, but still doing the job.
There's this thing called "efficiency" and this other thing: "economies of scale". Not to mention "closed cycles" and "ignoring important issues".
People in the power business have been thinking about these issues for many decades now. Lone inventors hardly ever do.
If you want to get a kilowatt of electricity, here's two ways:
(1) Put a kilo of dried cow dung into a small Stirling engine/generator. You'll get a kilowatt for X minutes per cow flop. (2) Put a kilo of dried cow dung into a large heat engine/generator, preferably anything but a Stirling. You'll get a kilowatt for X*Y minutes per cow flop. Where Y is the increased efficiency of a good heat engine.
The value of Y is arguable, but probably between 2 and 20. Stirling engines are not noted for their efficiency. To say the very least.
Looked at another way, the Stirling engine is going to require 2 to 20 times more cow flops, not to mention operating staff, people or vehicles to bring in cow flops from the surrounding area, etc.
That's why we don't already do this in the developed areas, it's not cost efficient to have anything smaller than a HUGE, well-designed, well-maintained, pollution-controlled generating station. HUGE as in many megawatts, enough for a whole village.
And there's the whole issue of cow flops. You and I probably think they cost nothing. Wrongo. They're already being used for cooking fuel and heating fuel. Every cow-flop that goes into a Stirling engine is one less cow-flop for cooking dinner. The fuel is *not* free. Same with other energy sources-- they're already being used way beyond the sustainable level. There are places where women already walk 30 km a day just to get firewood to cook dinner. We don't need another inefficient drain on scarce resources.
This backyard-burner thing is just going to deforest and pollute and smell up the world. No thanks.
Yes, there are theoretical quantum numbers that describe an electron. But you can't measure any of them without destroying the property. And they're not at any one particular value for more than an attosecond. And you can't match up properties with individual electrons, because there are no extra dimensions of freedom to tag electrons with. In computer lingo, for a viable memory, you need to have address:value pairs, but with electrons, there are no addresses, and no stable values either. Kinda totally skunked from the get-go.
Then some marketing genius figured out they could put a 15 cent audio input jack on the back of a radio and then sell the radio as "TV READY". The gist being that your radio wouldnt be obsolete when TV arrived-- you'd pipe the TV audio out through your radio speakers.
Of course when TV's did come out they all had built-in speakers, so nobody ever used this feature, but, yes, the radios were "TV Ready".
The basic problem is: you can't identify individual electrons. No way. Not ever. When they're circling an atom they're not discernible particles per se- they're an anonymous and homogenous cloud of probability. You can apply some energy and peel one electron off, but it's not like you're picking a particular electron. It's not like a bag of marbles and you're picking a particular one of a particular color. It's more like a jar of molasses and you're scooping out a spoonful.
Also electron spin isnt something that's latched to any one electron. Electrons exchange virtual photons many millions of million of times per second, which scrambles their properties.
So to beat this dead horse again: there's absolutely nothing to this story.
Seems Unlikely
The ENIAC had only 20 registers, holding 10 decimal digits each. Kinda hard to generate 1000 digits with only 200 digits of storage. There are algorithms that generate sequential digits of Pi, but I doubt if they were well known at that time.
>They had a process by which you had to review any functions that were going into the computer before you put them in...
Well, of course, because it took a lot of time and work to rewire the computer to run a new algorithm. And people were worth $2 an hour, while the computer probably was worth $100 an hour or more.
>Expensive but extremely effective at reducing software bugs in code...
I doubt if the early programmers were any better at finding bugs ahead of time than we are. They had the added complications of having to take into acount propagation delay and the many hardware glitches of each module. >The only time the machine was down was for tubes and hardware.
Er, No, it had to go down completely for reprogramming.
Three Hundred Fifty Milliwatts is 0.35 of one Watt. Most lasers are under 50% efficient. The deflection and modulation and optics are unlikely to be more than 50% efficient.
So imagine spreading 0.090 watts of light over a screen-sized area. Pretty dang dim! Like you'll need dark adapted eyes to even see the picture.
Still a neat device, but you're not going to run your own Drive-in movie theater with it.
Um, guess it depends on what you mean by "computing".
Years before the ENIAC was running, IBM was SELLING big ugly boxes that could add, subtract, and multiply, all electronically:
http://www-03.ibm.com/ibm/history/history/year_194 3.html
Fenynman used these at Los Alamos in 1944 to compute critical massses of Plutonium.
And these were programmable, to an extent, with plugboards, which incidentally was more flexible that the ENIAC arrangment of plugs and cables. You could swap plugboards in 5 seconds; reconfiguring ENIAC for a new program could take many many hours.
Eventually ENIAC was re-architected to take instructions from a huge bank of switches, before that it was program by plug.