is NOT doing this. She is not using a single photon to send the information, since there are no reliable single-photon sources. These quantum cryptography systems are a scam, since they really send some number of photons > 1.
If Eve intercepts just one photon in the burst, the other photons get through and the eavesdropping can't be detected.
This assumes that there are >1 photons in the pulse. The pulses are highly attenuated so that there are (on average) 0.1 photons in a pulse.
Of course, some pulses may contain >1 photons, but the probability of that is small enough that it's not enough to worry about.
i.e. Even if 1 in 2 pulses contain >1 photon, Eve still only has half of the key. Coupled with this fact, the other (single photon) pulses will most likely have been intercepted and allow alice and bob to know that they are being watched.
If you freeze a can of shaving foam in LN_2, you can remove the metal of the can leaving a frozen brick of foam and propellant. I've been told that on a hot day, 2cans will fill the average family car.
I don't think so. A quantum computer would, provided that I understand it all correctly, produce an (in)finite number of possible solutions.
Of course, the correct solution is in there somewhere, but how do you find out what it is?
Ok, if you use a single photon to send the information , it cannot be eavesdropped. But in the current networks it'll only go around a couple of meteres at Max and you can't use an amplifier/repeater with this.
Not so. My girlfriend is working on this. They have managed to send keys at large data-rates over conventional networks up to a distance of several tens of kilometers. In fibre networks, this distance approaches the pitch of the amplifiers.
You are right about not being able to amplify the signal though.
No, because that fibre is wired up collinearly with currently lit fibre. It will pass through the same amplifers etc. that the current networks use.
IOW just because it's dark doesn't make it an end to end single piece of glass.
What I'd love is something that works like Origin, Sigmaplot, Tecplot:
Graphical Interface, Curve Fitting, Data Analysis, Peak Picking, Data Manipulation etc...
I haven't found anything like this, despite a bit of googling around and an exploration of the ports/packages trees in a few distros.
This is what is keeping *nix off my work desktop (oh, and proper interfacing with the Novell Network (ncputils causes a kernel panic))
Whilst I agree that the British climate is mild:
Douglas (IOM) is at 54degrees North Anchorage, Alaska is at 61degrees North Not sure what your source was, but I'm not sure that I believe it:o)
[built-in] limited range transmitter I can't see them doing that, in the UK FM transmitters a la iTrip are not legal (although I believe that some retailers are selling them).
My alarm system has the ability to add a remote kepad, which offers a display of the alarms status and the possibility of looking through the last 50 events.
My plan is to hook the 4 lines (2 in/2 out) into the serial port of my server and then hack up some sort of program to send the required pulses back to the alarm system.
It might not be a particularly pretty solution, but I think that it could be rather useful.
Another possibility is using the control for the autodialler to get the network to warn me by email/SMS that it has been activated.
I don't know if apple has a gui config tool for any of them, but they are all very good, once you have them configured. There is some control over ipfw in the Sharing preferences pane, but it doesn't allow much more than opening ports for specific services.
You can however download an application called Brickhouse that allows a much greater range of control, and will even show you the firewall rules that ticking a load of checkboxes generates.
Like what is the usable range of the laser, can it fire through clouds. How long can the plan stay in flight.
I work in the optics field and there was a feature on the ABL in a recent magazine that I get (Optics and Laser Europe).
There are actually a number of lasers involved in the whole system:
CO_2 for ranging
Yb:YAG for targetting
Pulsed Nd:YAG for illumination
MW CO_2 for the final kill
CO_2 lasers are usually operated at 10.6m wavelength, which is absorbed fairly strongly by water in the atmosphere, so I wouldn't imagine that the beam has a huge range (probably large enough though).
What intrigued me most was that there is only enough fuel on board for ~12 shots, which isn't that much. The fully loaded laser system also weighs 77tons, so I imagine that the plane uses a good deal of fuel to stay up.
1) Radioactive material tends to be self-heating. That's why you can run a power station off it.
Radioactive material is only self heating when its above critical mass. Having a bomb go critical is not a good idea if you're trying to keep it hidden:)
3) According to the NewScientist article, "If disturbed or damaged, they were primed to explode within 10 seconds". Surely chickens *inside* the thing would disturb it, and set it off?
Good point, I think that the door was booby trapped (see my other post, but there was also a float switch in there, incase the device was underwater and the enemy sent divers down to disarm it.
Apparently the device that they have (pictured in the BBC article) was stored at an RAF base until fairly recently. When it was delivered to AWE for display, the airforce had rigged the door so that the timer started ticking when it was first opened:D
Blue Peacock does/did exist. I have the dubious privilege of having touched the only remaining example, housed in the museum collection at AWE. The other is (and I quote the curator here) `lost'!
It was a `landmine' designed to be set on a timer to ambush the Soviets as they advanced across Europe. It was based on the Blue Danube device that was the UK's first air-delivered nuclear weapon (essentially, they removed the fins).
The device had up to an 8-day timer, but could also be set off locally --- either by booby trap, incase it was discovered, or a trigger. Amusingly there was a 10 second delay when you operated the trigger, just time to duck and cover:o)
The chickens, though? That's clearly a hoax. Apart from anything else, the device was air and water tight.
That's interesting: Somerfield (my local supermarket) brought out a scheme whereby card-holders are entitled to special offers, where `normal' shoppers are not. Can you give me any references for this law?
From 1st December, it will be illegal to drive in the UK whilst holding your phone (or using a PDA etc. to access the 'net). Handsfree kits are allowed (AFAIK including headsets) as long as the phone is held in a cradle, not your hands. See here for the FAQs.
Slashdot Mirror
I know that Carlsberg brewery gives it's higher level employees ONE cartoon [sic] of beer per month
You mean something like this?
;-)
is NOT doing this. She is not using a single photon to send the information, since there are no reliable single-photon sources. These quantum cryptography systems are a scam, since they really send some number of photons > 1.
If Eve intercepts just one photon in the burst, the other photons get through and the eavesdropping can't be detected.
This assumes that there are >1 photons in the pulse. The pulses are highly attenuated so that there are (on average) 0.1 photons in a pulse.
Of course, some pulses may contain >1 photons, but the probability of that is small enough that it's not enough to worry about.
i.e. Even if 1 in 2 pulses contain >1 photon, Eve still only has half of the key. Coupled with this fact, the other (single photon) pulses will most likely have been intercepted and allow alice and bob to know that they are being watched.
If you freeze a can of shaving foam in LN_2, you can remove the metal of the can leaving a frozen brick of foam and propellant.
I've been told that on a hot day, 2cans will fill the average family car.
I think that he meant that iTunes 4.7.1 breaks the latest (at time of release) Hymn crack of your encrypted music.
I don't think so. A quantum computer would, provided that I understand it all correctly, produce an (in)finite number of possible solutions.
Of course, the correct solution is in there somewhere, but how do you find out what it is?
Not so. My girlfriend is working on this. They have managed to send keys at large data-rates over conventional networks up to a distance of several tens of kilometers. In fibre networks, this distance approaches the pitch of the amplifiers.
You are right about not being able to amplify the signal though.
No, because that fibre is wired up collinearly with currently lit fibre. It will pass through the same amplifers etc. that the current networks use.
IOW just because it's dark doesn't make it an end to end single piece of glass.
What I'd love is something that works like Origin, Sigmaplot, Tecplot: Graphical Interface, Curve Fitting, Data Analysis, Peak Picking, Data Manipulation etc... I haven't found anything like this, despite a bit of googling around and an exploration of the ports/packages trees in a few distros. This is what is keeping *nix off my work desktop (oh, and proper interfacing with the Novell Network (ncputils causes a kernel panic))
Whilst I agree that the British climate is mild: :o)
Douglas (IOM) is at 54degrees North
Anchorage, Alaska is at 61degrees North
Not sure what your source was, but I'm not sure that I believe it
[built-in] limited range transmitter
I can't see them doing that, in the UK FM transmitters a la iTrip are not legal (although I believe that some retailers are selling them).
My plan is to hook the 4 lines (2 in/2 out) into the serial port of my server and then hack up some sort of program to send the required pulses back to the alarm system.
It might not be a particularly pretty solution, but I think that it could be rather useful.
Another possibility is using the control for the autodialler to get the network to warn me by email/SMS that it has been activated.
I don't know if apple has a gui config tool for any of them, but they are all very good, once you have them configured.
There is some control over ipfw in the Sharing preferences pane, but it doesn't allow much more than opening ports for specific services.
You can however download an application called Brickhouse that allows a much greater range of control, and will even show you the firewall rules that ticking a load of checkboxes generates.
Sure, it's:
prattboy@gmail.com
I work in the optics field and there was a feature on the ABL in a recent magazine that I get (Optics and Laser Europe).
There are actually a number of lasers involved in the whole system:
CO_2 lasers are usually operated at 10.6m wavelength, which is absorbed fairly strongly by water in the atmosphere, so I wouldn't imagine that the beam has a huge range (probably large enough though).
What intrigued me most was that there is only enough fuel on board for ~12 shots, which isn't that much. The fully loaded laser system also weighs 77tons, so I imagine that the plane uses a good deal of fuel to stay up.
But you're not running Quartz Extreme which makes a big difference in speed True, but not having it doesn't make me want new hardware :)
Uh, my 5year old iMac is running the up-to-date OS. I'm not sure that I agree with you there.
iTunes isn't built-in to the OS. The implication is that the msMusicStore will be.
I wouldn't think so. I know of at least one airline (Lufthansa) who offer WLAN access on long haul flights.
BTW, what's the phone number for 911? 311 :op
I thought that Beagle was solar powered? ;)
Radioactive material is only self heating when its above critical mass. Having a bomb go critical is not a good idea if you're trying to keep it hidden :)
3) According to the NewScientist article, "If disturbed or damaged, they were primed to explode within 10 seconds". Surely chickens *inside* the thing would disturb it, and set it off?
Good point, I think that the door was booby trapped (see my other post, but there was also a float switch in there, incase the device was underwater and the enemy sent divers down to disarm it.
Apparently the device that they have (pictured in the BBC article) was stored at an RAF base until fairly recently. When it was delivered to AWE for display, the airforce had rigged the door so that the timer started ticking when it was first opened :D
It was a `landmine' designed to be set on a timer to ambush the Soviets as they advanced across Europe. It was based on the Blue Danube device that was the UK's first air-delivered nuclear weapon (essentially, they removed the fins).
The device had up to an 8-day timer, but could also be set off locally --- either by booby trap, incase it was discovered, or a trigger. Amusingly there was a 10 second delay when you operated the trigger, just time to duck and cover :o)
The chickens, though? That's clearly a hoax. Apart from anything else, the device was air and water tight.
How long before we get the `iPod recoevered in NYPD sting', similar to the Segway?
That's interesting: Somerfield (my local supermarket) brought out a scheme whereby card-holders are entitled to special offers, where `normal' shoppers are not. Can you give me any references for this law?
From 1st December, it will be illegal to drive in the UK whilst holding your phone (or using a PDA etc. to access the 'net). Handsfree kits are allowed (AFAIK including headsets) as long as the phone is held in a cradle, not your hands. See here for the FAQs.