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Comment Re:Not just Southern Spain (Score 3, Insightful) 172

It's important to note that this is a worst-case scenario
No. The worst case scenario they considered is "Business as usual".

  which typically means its somewhat improbable

Unfortunately not. It's the most likely scenario. The only positive note is that there doesn't appear to be a concerted effort to increase emissions so it's reasonably to reject scenarios with CO2e increasing faster than BaU (unless you think positive feedbacks for CO2 and CH4 emissions are starting to significantly kick in now)

Comment Re:Transfer the Responsibility (Score 1) 62

Make them liable if they do not start patching their own devices.

Don't necessarily even need the cost to go up.

Your device is found vulnerable to hackers. a) release a fix or b) release the source code in a form that allows others to fix it.

In a dream world I could imagine a time where the source code is released with the device. How much IP can there really be in a webcam? The vast majority of the work involved in writing a firmware from scratch would be researching how to address the hardware.

Comment Re:Escape (Score 1) 521

Capslock (shiftlock) was above the shift key on mechanical typewriters. When you pushed it down it pushed down the shift key with it and then latched. You pressed the shift key again to unlatch it.

Of course, as shift physically moved the hammers down, every single key went into it's shifted state.

But pushing shift was significantly more demanding than typing any of the other letters (at least on any mechanical typewriter I ever saw) so shift lock was more useful when typing repeated shifted values than it is today.

Comment Re: I tell them that I use wanker auth (Score 1) 430

You don't even need that. One finger unlocks the phone as normal. The other unlocks the phone but requires a pin as well (only needs to be one digit long) and an incorrect pin means that the phone shuts down. (or even that finger can make the phone shut down - however it should probably still require a pin even if there's *no* pin to unlock.

Don't know about obstruction of justice issues though...

Comment Re:No programmers' typeface (Score 1) 175

The international dialing code for Kazakhstan from the UK would be 00 7 (I've just looked it up). I've never heard anyone quote a Kazakhstan telephone number to call from the UK but I would expect them to say oh oh seven, not double oh seven. Apart from anything else, if you did try to tell someone a Kazakhstan telephone number and started double oh seven I'd expect them to not hear the rest of the number while they were laughing.

Comment Re:No programmers' typeface (Score 1) 175

Saying oh for zero is common in (British) English.

Dialing code for London:
020 - Oh two oh.

Start of a telephone number:
700 - seven double oh.

International dialing code for the US:
00 1 - oh oh one. (Don't know why we don't say double oh but I've never heard it said that way.)

Bus number:
205 - two oh five

In normal spoken or written English you can usually determine whether it's a zero or a letter-o from the context and where you can't it rarely matters.

Comment Re:a crypto-token already in your wallet (Score 1) 210

In the UK for while we started getting little keypads - completely stand alone that you plugged your card into, entered the PIN, entered some other details (e.g. amount of transaction if necessary) and then got an 8 digit code back to use as a passcode.

Completely OS/browser agnostic.

Unfortunately, it never really took off. I think people just didn't find it convenient enough to have the keypad. Of course, had it taken off then people would have had multiple keypads and left one at work etc so they wouldn't have to carry them around. Also, of course, it was completely interchangeable between cards, so the business that paid to produce and distribute would have ended up subsidizing other businesses anti-fraud department.

I don't know whether something similar is possible now using a phone and near field communication with the card. But even if it is, I cannot see it taking off. The businesses that could do this are too concerned with locking customers into their app rather than getting together to solve a common problem in a common way.

Similar has happened with "smart meters" for electricity. We're in the middle of a national rollout (costing goodness knows how much) but change supplier and your smart meter will revert to a dumb meter.

Comment Re:I Think this article might be a bit misleading. (Score 1) 189

Sorry, I'm hopeless at explaining hence why I could never teach.

There aren't two identical "messages" in quantum teleportation. That would violate the no-cloning theorem. Instead there's one message that originally exists at point A and later exists at point B instead.

But - and this is the bit where it involves QM weirdness - there is no way to "read" a complete quantum state and record it classically. Think of it as a two bit word in a computer where every time you read one bit the reading circuit randomly disturbs the other bit.

QM teleportation lets us move that word from one place to another without changing either bit (but note that the original word (letter) is destroyed in the process.)

Comment Re:I Think this article might be a bit misleading. (Score 1) 189

I don't know what else you saw but basically the entanglement leaves the target (teleportation) end in a superposition of four states, only one of which is the one you want the others are complementary states.

The sender makes a measurement at their end to determine which one of the four states is the correct one and then transmits it to the receiver. The receiver can then isolate the correct state from the others that would otherwise cancel out all knowledge of the original state.

Comment Re:Can Anyone Explain This To Me? (Score 2) 189

Oh well. I tried to write a comment with a diagram but hit submit instead of preview :-(

Consider four directions on a plane. x axis (we'll call that |+>), y axis (we'll call that |->) y=-x (we'll call that |0>) and y=x (we'll call that |1>)

Modulo some constant factors, I hope it's obvious that you can build up some of those vectors from others:

|1> = |+> + |->
|-> = |0> + |1>

These are the directions of a plane polarized photon.

We setup some photons that are polarized in the |1> direction and then pass them through a polarization filter.

If the filter points along the |1> direction then all of them pass. If the filter passes along the |0> direction then none of them pass.

Now we put the filter along the |-> direction. What happens.

|1> = s|+> + s|-> (s is 1/sqrt(2) - which can be deduced from standard trig - the lines must be the same length)

When we measure along the |-> direction the s|-> part will pass the filter but the s|+> part wont.

But an individual photon can't get dimmer therefore it must either pass or not. Half the photons do pass and half don't (and it's random whether any one photon gets through the detector)

The ones that do get through are now in state |-> which is also |0>+|1> (again with factors of sqrt 2)

If we now measure along the |1> direction again we now lose half the photons again (due to that |0> component)

Quantum teleportation involves taking a photon in state a|0> + b|1> (for unknown values of a and b) and taking very careful measurements that don't destroy a and b but instead transfer them to another photon without us actually knowing what they are.

Comment Re:Coincidence circuit again, i.e. filtering (Score 3, Informative) 189

You got the first paragraph right. But then got sidetracked by tennis balls.

There are *two* complementary quantum states that you can measure. Measuring one destroys all knowledge of the other.

There is no classical system that behaves like this, therefore any analogy that doesn't invoke some magic artificial property of a classical object won't represent what happens in QM.

In your example you need tennis balls that randomly change colour when you measure their spin and can magically reverse spin when you look what colour they are.

Comment Re:Confused (Score 1) 189

Quantum teleportation requires the use of a classical channel. The entangled particles can be exchanged in advance (provided they can be stored without breaking the entanglement which is difficult in practice but trivial in theory)

The classical data can only be transferred at the time the teleportation is done - hence that limits the speed of the teleportation to the speed of light.

Comment Re:I Think this article might be a bit misleading. (Score 5, Informative) 189

It's effectively** equivalent to having two identical letters containing a random message

No. you're describing entanglement.

Teleportation is subtly different.

Teleportation consists of transferring the quantum state of one particle to another particle via the use of entangled particles (and a classical channel)

The beauty of this is that the entangled state can be set up in advance. You then give me a particle that you might or might not know something about its quantum state (but importantly, I do not know what you know about it so cannot measure that quantum state in advance). I can transfer the state of that particle to another particle that Bob has via some entangled particles we exchanged earlier *plus* some standard classical information that goes over classical channels (it's this classical information that limits the teleportation to the speed of light)

The particle that Bob ends up with is in an identical state the the one you gave me (and which I still have).

N.B. This is quantum teleportation, not quantum cloning which is not possible. The act of getting the quantum state to Bob affects my particle in a way that means I cannot also extract any information from it about the original state of your particle.

Comment Re:Coincidence circuit again, i.e. filtering (Score 2) 189

I think you misunderstand.

The experiments that are discarded are where the two end points don't measure the same quantum variable.

For photons, for example, you can measure whether linear polarization is up-down/left-right or diagonal-left-up diagonal-right-down/diagonal-right-up diagonal-left down.

If both ends measure the up-down/left-right state then one will get up-down, one left-right. If both measure the diagonal polarization then again they will get complementary results. But if one measures up-down and the other measures diagonal then we cannot tell anything useful any more than trying to compare two sweets where one person says what shape it is and the other says what flavour it is so those results get discarded.

There is additional statistical analysis - due to the fact that these experiments are done on single photons and sometimes detectors fire when there is no photon and sometimes they don't fire when there is so we cannot expect 100% correlation - but that's nothing to do with discarding some of the results.

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