Quanta through a single slit -> fuzzy blob Quanta through a double slit -> light/dark bars
The trick was that if you set up a double-slit experiment and measured which of the two slits each quantum (I forget if it was photons or electrons) went through, the pattern reverted to the single-slit "fuzzy blob". In other words, the act of measuring at the slits destroyed the double-slit interference pattern, since it "collapsed the wavefunction".
Next topic: time travel and quantum physics as portrayed in Douglas Adams' "Dirk Gentley's Holistic Detective Agency"...
1) A person who says that he's seen microwaves go faster than the speed of light.
For me that was the most interesting part of the program. Basically, a microwave beam was split, and half of it went through air while half went through some barrier (apparantly by quantum tunneling). This signal arrived at the detector before the signal which went through air (by a significant margin; it's not just refractive index of air).
It looked like they were using a pulsed waveform, which might indicate this is more than just a phase velocity / group velocity confusion (electromagnetic waves can travel "faster than light" in an ionized plasma or a waveguide, but if you try to modulate any information on them, it always propagates "slower than light").
On the show there was some discussion about whether or not this apparatus could transmit information FTL; the researcher claimed it could and demonstrated it by modulating a piece of music through the apparatus. A fair bit of static, but easily recognizable. There is a large attenuation of the FTL signal; most photons don't make it through the barrier.
This was a table-top experiment, and it did not look like it would scale up to larger sizes very easily. Due to the large signal attenuation, you couldn't just stack devices end-to-end.
As far as time travel goes, SR shows that if you can send information FTL in opposite directions in two reference frames with a high relative velocity, then you can send it back in time. So, if you sent one of these microwave devices whizzing past another one in your lab, you might be able to send a couple of bits of information back in time by a nanosecond or so.
I like the Cobalt servers, and I might even buy one soon. Maybe there is a similar products out there to compare against?
A somewhat similar product is the StrongARM-based Netwinder, formerly of Corel Computer Corporation, now found here. Nice hardware, but a pity about that new domain name and logo...
That's ADSL in Vancouver BC, not cable. The way it works is, when you get an address assigned by DHCP, their server sets up this MAC-based hostname mapped to your IP address. You are then supposed to log in to a special SSL web page with your userid and password. Once you do this, a static hostname (in the format "userid"."ISP".bconnected.net) is assigned to your IP address. So, when the system is operating properly, the MAC-based hostname will not be exported to the world at large.
Happily, one provider is now offering static IP addresses with ADSL, so in a few weeks I will be able to ditch their kludged DHCP system. Yay!
If you look at http://www.macmillansoftware.com, you will see that they offer several different Linux packages (and more if you search under "Operating Systems"/"Linux").
They have a "starter kit" based on Caldera, "The Complete Linux" (which is the Mandrake-based one), and "Deluxe Linux" which doesn't specify a distribution. They also have (or had) a "Red Hat" distribution complete with RedHat's logo; I don't know if this was officially licensed or not.
These Macmillan boxes are now quite common in local mass-market stores, but I have just recently started to see Official RedHat box sets and I have yet to see an official Mandrake, SuSE, or Caldera.
I bought the Macmillan Complete Linux 6.0 (Mandrake) for CDN$35. The box contains a nicely-printed manual and installation guide, some other advertising and booklets, a letter saying that this is an unofficial distribution and who to call for tech support (Romnet Support Services Inc.), a boot floppy, and 3 CD's. Two of these are the Mandrake binary and source discs, while the 3rd contains PDF versions of the books "Linux Unleashed", "Using Linux", and "Teach Yourself Linux" as well as a limited version of Partition Magic. This 3rd cd is under not freely distributable, and comes in its own license-covered envelope for easy disposal by GPL purists.
One nice thing about the Canadian style of nuclear reactors is that they run on natural uranium (with heavy water as the moderator), thus eliminating some of these dangerous processing steps.
I think this would be against the spirit of the awards, since these people caused so much external damage. Darwin Awards are (IMHO) meant for those who produce a net benefit to society by removing themselves in amusing ways without hurting others.
Adding to the ugliness, they were mixing the uranium with nitric acid (from the CNN story).
As for the blue flash, that is indeed bad news. A while ago I was watching some documentary about the early days of the US nuclear program, and there was a similar event where somebody slipped while assembling a plutonium bomb core. The two halves bumped together, causing a blue flash, and delivering a fatal-within-a-week radiation dose.
Actually, re-reading the article, it's possible that the blue flash wasn't in the air, since they were mixing this stuff in a tank of water. So maybe it's not quite as bad.
Open source code greatly reduces the ability of a company to screw a user community. IBM has been doing some good things lately, so why not forgive them some of their past sins and thank them for their participation?
It takes nearly 100 times the electricity at 14 Hz to kill a man than it does at the peak dangerousity of 60Hz.
Maybe, but transformers would have to be a lot larger and heavier to handle AC at 14 Hz. Higher frequencies mean smaller transformers, which is why switching power supplies (>20kHz) are much smaller than equivalently-rated linear supplies. On the other hand, radiated interference and transformer core losses go up with frequency. 60 Hz might have been a decent compromise at the time.
Primarily for his invention that would have allowed for nearly free electrical generation by installing very very tall towers around the planet which would use the Earth's magnetic field to generate pollutionless electricity!
Yes, but does this invention work? Really? And if so, why not build one today, now that Edison is dead and gone? There is a lot of pseudoscience surrounding Tesla, and not all ideas credited to him would actually work. Some of his other ideas, like beaming power from huge antenna towers, would work but are impractical for other reasons (people are worried about cancer from cellular phones; imagine the panic from a Tesla-style power station that lit up fluorescent tubes 10 miles away!).
However, in general I agree that Tesla was a genius and Edison probably was a mean bastard. He's certainly why most people believe that patents are good for society.
But I can unplug my ethernet card and install another one, or maybe (depending on model) re-program the MAC in my existing card. Everyone knows this, so nobody makes any claim that my MAC address identifies *ME* personally in any business transaction across the net.
The MAC address is used for node-locking certain types of software (the kind of software that costs more than your computer did, and where the salescreature gets a free trip to Hawaii if you buy the "gold" support package).
The noise about the Intel ID was not that it existed, but that Intel planned to use it in a very silly and dangerous manner.
You need this to be handled by a trusted and independent non government organization that is charted with the sole purpose of retrieveing stolen PCs, nothing else.
Yeah, but you know it will end up being handled by the Bureau of Alcohol, Tobacco, PCs, and Firearms.
There are already private companies that do this - if the criminal doesn't have the sense to blank the hard drive, a little program will phone in to the central office the first time he goes online. It's a voluntary system for those who wish to trade off a bit of privacy (and a bit of cash) for an improved chance of recovering stolen property. It only works because most criminals don't know about it yet.
I wonder if it's time for the FCC to relinquish control of the broadcast spectrum to the UN or some other similar international agency? Or maybe, an ISO standard for frequency allocations.
Sounds like a job for the International Telecommunication Union. There's some info about wireless network access here, though I'm not familiar with the details of any of this.
Has anyone else noticed the similarities between Sirrus Cybernetics Corporations and Microsoft?
Well, since Douglas Adams is a Mac person, it's probably more than just a coincidence. It sure fits well, especially the bits regarding their products: "their fundamental design flaws are completely obscured by their superficial design flaws", or in other words you are "blinded to the essential uselessness of them by the sheer satisfaction of getting them to work at all".
Sounds rather familiar. Now what was that bit about being the first against the wall when the revolution comes?:-)
I wonder what the pay scale might be for a full time Hitchhiker's Guide Field Agent...
... and what currency you'd be paid in. Better make sure that Earth banks will accept it before you sign any contracts; you don't want to end up with a warehouse full of non-negotiable triangular rubber coins.
Also, the Commodore disk drives (1541 and 1571) had their own on-board 6502 processor, RAM (8K ?) and ROM (32K ?). They communicated over a serial bus, and you could even chain two drives together and install a little program to automatically copy disks (which would still work after unplugging the computer).
Although the PIC branching logic seems a bit confusing, it makes sense at a low level. The PIC is pipelined so that the next instruction is being fetched while the current one executes. In the case that a conditional instruction wants to "skip", the CPU just replaces the fetched instruction with a NOP.
The aspect of the PIC which I found the most confusing was trying to do a table lookup from ROM. I was used to a 6502/68000 style where you would use an indirect addressing mode, like "move.b (a0),d0". On the PIC you have to call a subroutine which adds the desired table offset to the program counter register, thus jumping somewhere into a block of RETLW xx instructions (which return from a subroutine with a constant 'xx' in the W register). It gets harder if your table crosses a page boundary.
Still, apart from a few oddities, I like PICs. There is a series with Flash memory (e.g. 16F84) rather than EPROM, which greatly speeds up the development cycle time (no more UV-erasing). There's also a series (e.g. 12CE518) which comes in an 8-pin package with up to 6 I/O lines, and a serial EEPROM on board.
Don't know about the PET, but the C-128 had a Z80 in addition to the 8502 (6502-derivative) main CPU. However, you could only use one CPU at a time (Z80 for CP/M compatibility, 8502 for everything else).
While I dislike the Wintel platform, I once thought that the Amiga perhaps may have been better off building on the PC platform -- add a graphics card (with the Amiga chips) and a separate OS (co-resident with Windoze).
They did it the other way round - you could buy a "Bridgeboard" card that contained an 80x86 processor and some interface logic. You had the option of sharing the Amiga RAM and hard disk, or installing dedicated ones for faster performance. There were also a few ISA slots to add PC accessories like video cards (since the graphics were *slow* when emulated through the Amiga OS).
I had a 486 Bridgeboard in my A4000, and it worked, but in the end it was just way overpriced and underpowered compared to the PC market.
I think the 'spirit' got downsized years ago, in the final stages of Commodore's ownership. That article is just empty PHB-speak, and doesn't give me any hope for the future of the Amiga. Rather than waiting for a magic box that may never appear (and might suck even if it does appear), Amiga enthusiasts could try to pressure developers into improving Linux to a point where it would be an acceptable replacement for the Amiga OS. I can think of a couple of obvious items, like the handling of removable media or the Amiga's concept of "screens" (though Linux's virtual consoles are similar). However, I'm sure there are many more.
Amiga fans: What are the features that you miss the most when using Linux?
Neat idea, but your portable player would probably need some AI to figure out what type of music you like, so that you don't have to tune through 140 channels of crap and soft-drink jingles before finding a decent song. And once you had that level of technology, you could probably make a portable box that would automatically generate music that you liked (some algorithms seeded by random data from the environment around you? Genetic music algorithms swapped with whomever you pass on the sidewalk?) rather than having to receive it.
There's a difference between "better sound" and "faithful reproduction". The test for a storage medium should be whether or not a trained listener can distinguish between the signal going into it, and the signal coming out of it.
Now, a test for LP/CD is to: 1. Play an LP on your player, digitize its output signal, and burn a CD of it. 2. Connect the LP player and the CD player to an AB switchbox going into your amp. 3. Conduct a double-blind test to see whether differences are detectable. 4. Repeat steps 1-3, but starting with a CD and mastering an LP from the player's output.
A test like this will help to show whether the CD actually loses information that was present in the LP, or whether it's just that the characteristic distortion of an LP sounds "good" to your ears. You could do a similar "live" test with a back-to-back ADC and DAC at various resolutions and sampling rates, to see exactly where the quantization errors became audible. Somebody's probably done this already, but I don't have any links.
Slashdot Mirror
Quanta through a single slit -> fuzzy blob
Quanta through a double slit -> light/dark bars
The trick was that if you set up a double-slit experiment and measured which of the two slits each quantum (I forget if it was photons or electrons) went through, the pattern reverted to the single-slit "fuzzy blob". In other words, the act of measuring at the slits destroyed the double-slit interference pattern, since it "collapsed the wavefunction".
Next topic: time travel and quantum physics as portrayed in Douglas Adams' "Dirk Gentley's Holistic Detective Agency"...
1) A person who says that he's seen microwaves go faster than the speed of light.
For me that was the most interesting part of the program. Basically, a microwave beam was split, and half of it went through air while half went through some barrier (apparantly by quantum tunneling). This signal arrived at the detector before the signal which went through air (by a significant margin; it's not just refractive index of air).
It looked like they were using a pulsed waveform, which might indicate this is more than just a phase velocity / group velocity confusion (electromagnetic waves can travel "faster than light" in an ionized plasma or a waveguide, but if you try to modulate any information on them, it always propagates "slower than light").
On the show there was some discussion about whether or not this apparatus could transmit information FTL; the researcher claimed it could and demonstrated it by modulating a piece of music through the apparatus. A fair bit of static, but easily recognizable. There is a large attenuation of the FTL signal; most photons don't make it through the barrier.
This was a table-top experiment, and it did not look like it would scale up to larger sizes very easily. Due to the large signal attenuation, you couldn't just stack devices end-to-end.
As far as time travel goes, SR shows that if you can send information FTL in opposite directions in two reference frames with a high relative velocity, then you can send it back in time. So, if you sent one of these microwave devices whizzing past another one in your lab, you might be able to send a couple of bits of information back in time by a nanosecond or so.
I like the Cobalt servers, and I might even buy one soon. Maybe there is a similar products out there to compare against?
A somewhat similar product is the StrongARM-based Netwinder, formerly of Corel Computer Corporation, now found here.
Nice hardware, but a pity about that new domain name and logo...
00-4c-ec-2b-2d-00.bconnected.net
That's ADSL in Vancouver BC, not cable. The way it works is, when you get an address assigned by DHCP, their server sets up this MAC-based hostname mapped to your IP address. You are then supposed to log in to a special SSL web page with your userid and password. Once you do this, a static hostname (in the format "userid"."ISP".bconnected.net) is assigned to your IP address. So, when the system is operating properly, the MAC-based hostname will not be exported to the world at large.
Happily, one provider is now offering static IP addresses with ADSL, so in a few weeks I will be able to ditch their kludged DHCP system. Yay!
If you look at http://www.macmillansoftware.com, you will see that they offer several different Linux packages (and more if you search under "Operating Systems"/"Linux").
They have a "starter kit" based on Caldera, "The Complete Linux" (which is the Mandrake-based one), and "Deluxe Linux" which doesn't specify a distribution. They also have (or had) a "Red Hat" distribution complete with RedHat's logo; I don't know if this was officially licensed or not.
These Macmillan boxes are now quite common in local mass-market stores, but I have just recently started to see Official RedHat box sets and I have yet to see an official Mandrake, SuSE, or Caldera.
I bought the Macmillan Complete Linux 6.0 (Mandrake) for CDN$35. The box contains a nicely-printed manual and installation guide, some other advertising and booklets, a letter saying that this is an unofficial distribution and who to call for tech support (Romnet Support Services Inc.), a boot floppy, and 3 CD's. Two of these are the Mandrake binary and source discs, while the 3rd contains PDF versions of the books "Linux Unleashed", "Using Linux", and "Teach Yourself Linux" as well as a limited version of Partition Magic. This 3rd cd is under not freely distributable, and comes in its own license-covered envelope for easy disposal by GPL purists.
One nice thing about the Canadian style of nuclear reactors is that they run on natural uranium (with heavy water as the moderator), thus eliminating some of these dangerous processing steps.
I think this would be against the spirit of the awards, since these people caused so much external damage. Darwin Awards are (IMHO) meant for those who produce a net benefit to society by removing themselves in amusing ways without hurting others.
Adding to the ugliness, they were mixing the uranium with nitric acid (from the CNN story).
As for the blue flash, that is indeed bad news. A while ago I was watching some documentary about the early days of the US nuclear program, and there was a similar event where somebody slipped while assembling a plutonium bomb core. The two halves bumped together, causing a blue flash, and delivering a fatal-within-a-week radiation dose.
Actually, re-reading the article, it's possible that the blue flash wasn't in the air, since they were mixing this stuff in a tank of water. So maybe it's not quite as bad.
So what if you throw some extra coal in the furnace in a coal plant? You'll cough out some extra sulphur because the burning is less clean.
Some extra radioactive Thorium, too...
http://www.em.doe.gov/tie/fall30.html
TANSTAAFL.
Open source code greatly reduces the ability of a company to screw a user community. IBM has been doing some good things lately, so why not forgive them some of their past sins and thank them for their participation?
It takes nearly 100 times the electricity at 14 Hz to kill a man than it does at the peak dangerousity of 60Hz.
Maybe, but transformers would have to be a lot larger and heavier to handle AC at 14 Hz. Higher frequencies mean smaller transformers, which is why switching power supplies (>20kHz) are much smaller than equivalently-rated linear supplies. On the other hand, radiated interference and transformer core losses go up with frequency. 60 Hz might have been a decent compromise at the time.
Primarily for his invention that would have allowed for nearly free electrical generation by installing very very tall towers around the planet which would use the Earth's magnetic field to generate pollutionless electricity!
Yes, but does this invention work? Really? And if so, why not build one today, now that Edison is dead and gone? There is a lot of pseudoscience surrounding Tesla, and not all ideas credited to him would actually work. Some of his other ideas, like beaming power from huge antenna towers, would work but are impractical for other reasons (people are worried about cancer from cellular phones; imagine the panic from a Tesla-style power station that lit up fluorescent tubes 10 miles away!).
However, in general I agree that Tesla was a genius and Edison probably was a mean bastard. He's certainly why most people believe that patents are good for society.
But I can unplug my ethernet card and install another one, or maybe (depending on model) re-program the MAC in my existing card. Everyone knows this, so nobody makes any claim that my MAC address identifies *ME* personally in any business transaction across the net.
The MAC address is used for node-locking certain types of software (the kind of software that costs more than your computer did, and where the salescreature gets a free trip to Hawaii if you buy the "gold" support package).
The noise about the Intel ID was not that it existed, but that Intel planned to use it in a very silly and dangerous manner.
You need this to be handled by a trusted and independent non government organization that is charted with the sole purpose of retrieveing stolen PCs, nothing else.
Yeah, but you know it will end up being handled by the Bureau of Alcohol, Tobacco, PCs, and Firearms.
There are already private companies that do this - if the criminal doesn't have the sense to blank the hard drive, a little program will phone in to the central office the first time he goes online. It's a voluntary system for those who wish to trade off a bit of privacy (and a bit of cash) for an improved chance of recovering stolen property. It only works because most criminals don't know about it yet.
I wonder if it's time for the FCC to relinquish control of the broadcast spectrum to the UN or some other similar international agency? Or maybe, an ISO standard for frequency allocations.
Sounds like a job for the International Telecommunication Union. There's some info about wireless network access here, though I'm not familiar with the details of any of this.
Has anyone else noticed the similarities between Sirrus Cybernetics Corporations and Microsoft?
:-)
Well, since Douglas Adams is a Mac person, it's probably more than just a coincidence. It sure fits well, especially the bits regarding their products: "their fundamental design flaws are completely obscured by their superficial design flaws", or in other words you are "blinded to the essential uselessness of them by the sheer satisfaction of getting them to work at all".
Sounds rather familiar. Now what was that bit about being the first against the wall when the revolution comes?
I wonder what the pay scale might be for a full time Hitchhiker's Guide Field Agent...
... and what currency you'd be paid in. Better make sure that Earth banks will accept it before you sign any contracts; you don't want to end up with a warehouse full of non-negotiable triangular rubber coins.
Also, the Commodore disk drives (1541 and 1571) had their own on-board 6502 processor, RAM (8K ?) and ROM (32K ?). They communicated over a serial bus, and you could even chain two drives together and install a little program to automatically copy disks (which would still work after unplugging the computer).
Of course, we didn't have RC5 back then...
>what is the most powerful processor available that doesn't use a cooling fan?
Possibly one of the StrongARMs (e.g. the Netwinder's SA110 @275MHz)?
Although the PIC branching logic seems a bit confusing, it makes sense at a low level. The PIC is pipelined so that the next instruction is being fetched while the current one executes. In the case that a conditional instruction wants to "skip", the CPU just replaces the fetched instruction with a NOP.
The aspect of the PIC which I found the most confusing was trying to do a table lookup from ROM. I was used to a 6502/68000 style where you would use an indirect addressing mode, like "move.b (a0),d0". On the PIC you have to call a subroutine which adds the desired table offset to the program counter register, thus jumping somewhere into a block of RETLW xx instructions (which return from a subroutine with a constant 'xx' in the W register). It gets harder if your table crosses a page boundary.
Still, apart from a few oddities, I like PICs. There is a series with Flash memory (e.g. 16F84) rather than EPROM, which greatly speeds up the development cycle time (no more UV-erasing). There's also a series (e.g. 12CE518) which comes in an 8-pin package with up to 6 I/O lines, and a serial EEPROM on board.
Don't know about the PET, but the C-128 had a Z80 in addition to the 8502 (6502-derivative) main CPU. However, you could only use one CPU at a time (Z80 for CP/M compatibility, 8502 for everything else).
While I dislike the Wintel platform, I once thought that the Amiga perhaps may have been better off building on the PC platform -- add a graphics card (with the Amiga chips) and a separate OS (co-resident with Windoze).
They did it the other way round - you could buy a "Bridgeboard" card that contained an 80x86 processor and some interface logic. You had the option of sharing the Amiga RAM and hard disk, or installing dedicated ones for faster performance. There were also a few ISA slots to add PC accessories like video cards (since the graphics were *slow* when emulated through the Amiga OS).
I had a 486 Bridgeboard in my A4000, and it worked, but in the end it was just way overpriced and underpowered compared to the PC market.
"Theoretically, if I cut costs enough, we'll be profitable without selling any product".
I think the 'spirit' got downsized years ago, in the final stages of Commodore's ownership. That article is just empty PHB-speak, and doesn't give me any hope for the future of the Amiga. Rather than waiting for a magic box that may never appear (and might suck even if it does appear), Amiga enthusiasts could try to pressure developers into improving Linux to a point where it would be an acceptable replacement for the Amiga OS. I can think of a couple of obvious items, like the handling of removable media or the Amiga's concept of "screens" (though Linux's virtual consoles are similar). However, I'm sure there are many more.
Amiga fans: What are the features that you miss the most when using Linux?
Neat idea, but your portable player would probably need some AI to figure out what type of music you like, so that you don't have to tune through 140 channels of crap and soft-drink jingles before finding a decent song. And once you had that level of technology, you could probably make a portable box that would automatically generate music that you liked (some algorithms seeded by random data from the environment around you? Genetic music algorithms swapped with whomever you pass on the sidewalk?) rather than having to receive it.
There's a difference between "better sound" and "faithful reproduction". The test for a storage medium should be whether or not a trained listener can distinguish between the signal going into it, and the signal coming out of it.
Now, a test for LP/CD is to:
1. Play an LP on your player, digitize its output signal, and burn a CD of it.
2. Connect the LP player and the CD player to an AB switchbox going into your amp.
3. Conduct a double-blind test to see whether differences are detectable.
4. Repeat steps 1-3, but starting with a CD and mastering an LP from the player's output.
A test like this will help to show whether the CD actually loses information that was present in the LP, or whether it's just that the characteristic distortion of an LP sounds "good" to your ears. You could do a similar "live" test with a back-to-back ADC and DAC at various resolutions and sampling rates, to see exactly where the quantization errors became audible. Somebody's probably done this already, but I don't have any links.