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Comment Re: Perfect Illustration (Score 1) 339

Well, there is a difference between what it does mean and what it should mean. I have tried several times to refer to the continent as "America" in conversation, and it never worked, people always thought I was referring to the US. For me this clearly means that the word "America", in english, means the country.

This is language-dependent, though. In german " Amerika" also means the country, whereas in portuguese and spanish "América" always mean the continent.

Comment Re:"record low"...maybe the current ratings work (Score 1) 165

I don't think there is a confusion about what the rule is, there is disagreement about the usefulness of the rule.

In my situation, there was a car to my right that was also turning left, and no car to my left, which is why I ended up in the leftmost lane in the first place. To follow this rule of "constant number of inside lanes" I would have had to wait -- in the middle of an intersection -- until I could get behind the car to my right, or he should wait for me to get in front of him (which he didn't). Both solutions would disturb the traffic flow more than what actually happened. And this is the rule I always follow: minimize disturbance to traffic flow.

But even leaving aside issues of traffic flow, I don't see how the existence of the rule here would be of benefit to anyone. Imagine that you are the car in the oncoming traffic, that also wants to turn right. In a nice orderly intersection the rule can be useful: you can see where each car comes from and where they (should) go to, so its easy to mix within the flow without creating a mess. But if you cannot clearly see the path each car is taking (because the intersection is complex), then it doesn't matter whether they follow the lane-rule: you should wait anyway for them to clear the intersection before turning right.

Comment Re:"record low"...maybe the current ratings work (Score 1) 165

What you say makes sense if the streets are laid out in a nice orderly grid, or if at least there are some dashed lines connecting lanes between the intersecting roads. But this is not the case in Vienna; it grew out of a medieval city, so the intersections are pretty much a random number of streets with a random number of lanes meeting in random angles. I would never trust drivers here to even know which lane they are supposed to go to, so yeah, the bandwidth is rather small in these intersections.

This is, as a matter of fact, what happened to me. I was in the middle lane of a three-lane street, turned left onto a two-lane street, and ended up if the leftmost lane. Blam, failed, because they decided that "not changing lane" meant taking the rightmost lane.

Comment Re:"record low"...maybe the current ratings work (Score 2) 165

There's only so much that you can get out of better driver's education and stricter testing; here in Vienna the testing is becoming stricter and stricter all the time, to the point that they have covered every possible bad driving behaviour, and are moving into the terrain of pure bullshit.

Here it is considered an error, for example, to grab the steering wheel in anything position other than the 9:15 one; even the 10:10 position is considered an error, even though it was the mandatory position two years ago. Here you can fail the driving test if you change your driving lane while making a turn; I have a friend who failed her test because she was less than one meter way from the next car during a traffic jam.

I think the result from these overly strict regulations is that it simply gets more expensive to get a driver's license, without actually improving traffic safety. It can even be detrimental to safety, if the kids are learning this stuff instead of focusing on paying attention to pedestrians and other cars.

Comment Re:As a geneticist, Church knows zero about ageing (Score 1) 385

If aging is unrelated to genetics, I wonder what I could possibly be related to; maybe some magical thing that determines all our biological processess but is not DNA? Or are you trying to claim that ageing is not a biological process? What can it be, radioactive decay? Wrath of the gods?

Comment Re:Real nerd news. Reminds me of me. (Score 1) 247

I don't believe your story. It's completely trivial to make uniform pseudorandom numbers: 01010101010101010101. The trick is getting them to be independent, which the previous sequence isn't. So one usually detects poor pseudorandom number generators by finding some correlation in them, like with RANDU.

Comment Re:50 years (Score 2) 65

Hmm? Are you just trolling, or you actually think that? The moon was first mapped by Luna 3 and Zond 3, that's why the geographical features of the far side are all named after Soviet scientists. And the first probe to orbit the moon was Luna 10. You shouldn't let your ideology get more important than the facts.

Comment Re:This is huge (Score 1) 214

I'm not seeing much of a disagreement with me in your latest reply. For the most part, you appear to be restating in your own words things I've also said. I think we now agree on what the choice is: locality, or common cause. If you want to maintain locality then you have to deny a common cause in these entanglement experiments. That is, even though the 'entangled' particles demonstrate properties that are highly correlated, the correlation nevertheless lacks a common cause. Or, has a common cause that occurs AFTER the experiment is performed (or thereabouts). Do you agree with this characterisation?

Good that we have cleared things up. I can agree with your characterisation if you are more specific about "common cause": what we have to give up is Reichenbach's common cause principle, which is not the only sort of common cause imaginable. In fact, we know the correlations exist because of the entangled state, so the state is some kind of common cause, just not Reichenbach's.

And to conclude, I'd like to bet that you are not a physicist (probably a philosopher?), if you think it is in any way tenable to abandon locality.

I'm in favour of letting people see the results of their bets. I have a background in physics, but my main area is indeed philosophy, so well done :)

I would be interested to hear why you think abandoning locality would be a big problem.

Ahá! For once the stereotypes worked =)

Well, for starters, it is hard to reconcile nonlocality and relativity; it requires the nonlocal influences to be some conspiratorial sort that do not actually lead to any superluminal signalling, and I find this conspiracy distasteful. Furthermore, it makes the scientific endeavour very suspect, if not actually impossible. A key hability in science is to isolate some system, control its variables, and see how changing them affect the system. In a nonlocal world, the first step of isolating the system is already impossible, so you're not going to be able to have much control over your system, and this reduces what you can learn about it.

Comment Re:This is huge (Score 1) 214

The state change only becomes effective when the results from the two
labs are brought together and are jointly analyzed, which can happen
centuries later. Bohmians like Maudlin tend to confuse such changes in
distributions with a change in the world, because the notions of states
and wave functions are reified, and considered as some real thing out

Note here that locality is maintained by not having any appropriate change in the world until the two labs bring their results together! This is what I take Wiseman to be referring to when he talks about giving up on correlation. In the Nature article I linked earlier:

No, it's not. Werner is talking about the nonlocality of the wavefunction collapse, whereas Wiseman is talking about abandoning Reichenbach's common cause principle.

But one can go further, by recalling that local causality rests on two principles: Einstein’s principle of relativistic causality, and the principle of common cause. Thus Bell’s 1976 theorem can be restated as: either causal influences are not limited to the speed of light, or events can be correlated for no reason.


Those who hold Einstein’s principle to be inviolable (the localists) must conclude that some events are correlated for no reason. A challenge for them is: if correlations do not necessarily imply a cause, when should scientists look for causes, and why?

and from the arxiv.org paper,

In conclusion, for a proper appreciation of the foundational importance of Bell’s
theorem to physics, information science, and the philosophy of causation, one should be
familiar with both the 1964 Bell’s theorem and the 1976 Bell’s theorem, even though
they are logically equivalent. The former proves that quantum phenomena are either
nonlocal (in a “causation by agents” sense) or undetermined, while the latter proves
that quantum phenomena violate local causality (in a “common cause for correlations”

Let me clarify what they are talking about: Bell's theorem follows from local causality. Local causality itself can be derived either from the conjunction of determinism and locality, or from the conjunction of Reichenbach's common cause principle and locality. So, if you want to keep locality, you have to give up determinism (as shown by Bell's first theorem) and Reichenbach's common cause principle (as shown by Bell's second theorem, in a more modern reading). Maybe reading this paper of Wiseman will make things clearer.

While Wiseman, Werner, and Maudlin may be all saying subtly different things, their understanding seems to me largely the same. Maudlin shows (as Bell did), that embracing indeterminism isn't enough. What Wiseman points out is that the choice isn't between locality and indeterminism, but between locality and correlation. What Werner says is that the correlation comes from entirely local events, presumably late occuring: when the labs bringing their results together. You have given up on indeterminism, but that isn't one of the options on the table.

As I said before, if indeterminism is the price to pay for keeping lcality, then we're much better off ditching locality. The same goes if one is referring to giving up on correlation of events. But keep in mind the kind of correlation here one needs to give up: it's the correlation we find in the kind of experiment given in this slashdot article. These are very *strong* correlations. How crazy does a view have to be before we give up locality?

Come on, Werner and Wiseman largely agree, but they are talking about different things. Maudlin is in violent disagreement with everybody else. But I'm repeating myself here. What I'd like to point out is what exactly is meant by "giving up on correlation of events". What one needs to give up is a very specific thing, namely Reichenbach's common cause principle, essentially that probabilities of two distant events will factorize when conditioned on their common cause. The mainstream view is that Reichenbach's principle has been falsified, and that we need to develop a true, quantum version of it. See, for example, this paper.

And to conclude, I'd like to bet that you are not a physicist (probably a philosopher?), if you think it is in any way tenable to abandon locality.

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