Is quantum physics actually an improvement in the theory of how reality works?

It explains everything microscopic. For example, the stability of atoms. Why doesn't an electron just spiral into the nucleus and stay there? The uncertainty principle means it can't be both localized at a point and have a fixed momentum of zero. If the position wavefunction is a big spike concentrated at a point, then the momentum wavefunction, which is the Fourier transform of the position wavefunction, will have a nonzero probability over a considerable range of momenta, so the position wavefunction will start leaking out of the nucleus in the next moment. The lowest energy stable state for the electron is one which is centered on the nucleus, but has a small spread in position space and a small spread in momentum "space".

However, every quantum theory ever used has a classical conceptual beginning. You posit the existence of fields or particles interacting in some classical way, and then you "quantize" this. For example, the interaction between electron and nucleus is just electromagnetism, as in Faraday, Maxwell, and Einstein. But you describe the electron (and the nucleus too, if necessary) by a probabilistic wavefunction rather than a single point in space, and you also do the same for the electromagnetic field. Curiously, when you do this for the field, you get particles as emergent phenomena. A "photon" is actually something like a bookkeeping device for the probabilistic movement of energy within the quantized electromagnetic field. You can also get electrons and nucleons (and their antiparticles) from fields in this way, so everywhere in elementary particle physics, you have this "field/particle duality". For every type of elementary particle, there is a fundamental field, and vice versa. The basic equations that get quantized are field equations, but the result of quantization gives you particle behavior.

Everyone wants to know how to think about the uncertainty in quantum physics. Is it secretly deterministic and we just need a better theory, or do things really happen without a cause; does the electron always have a definite position even when we can't see it, or is it somehow not anywhere in particular; and so on. These conceptual problems exist because we have no derivation of quantum wavefunctions from anything more fundamental. This is unlike, say, the distributions in ordinary probability theory. You can describe the output of a quincunx using the binomial distribution, but you also have a "microscopic model" of where that distribution comes from (balls bouncing left and right as they fall down). We don't have any such model for quantum probabilities, and it would be difficult to produce (see: "Bell's theorem"). Sum over histories looks like such a model, but the problem is that histories can cancel ("interfere destructively"). It is as if, in the quincunx device, there were slots at the bottom where balls never fell, and you explained this by saying that the two ways to get there cancelled each other out - which is how sum-over-histories explains the double-slit experiment: no photons arrive in the dark regions because the "probability amplitude" for getting there via one slit cancels the amplitude for getting there from the other slit.

As a practical matter, most particle physicists think of reality in quasi-classical terms - in terms of fields or particles, whichever seems appropriate, but then blurred out by the uncertainty principle. Sum over histories is an extension of the uncertainty principle to movement and interaction, so it's a whole process in time which is uncertain, rather than just a position.

The actual nature of the uncertainty is a philosophical or even ideological matter. The traditional view effectively treats reality as classical but blurry. There is a deterministic alternative theory (Bohmian mechanics) but it is obscure and rather contrived. The popular view on this site is "the many-worlds interpretation" - all the positions, all the histories are equally real, but they live in parallel universes. I believe this view is, like Bohmian mechanics, a misguided philosophical whimsy rather than the future of physics. Like Bohmian mechanics, it can be given a mathematical and not just a verbal form, but it's an artificial addition to the real physics. It's not contributing to progress in physics. Its biggest claim to practical significance is that it helped to inspire quantum computation; but one is not obliged to think that a quantum computer is actually in all states at once, rather than just possibly in one of them.

So, I hold to the traditional view of the meaning of quantum theory - that it's an introduction of a little uncertainty into a basically classical world. It doesn't make sense as an ultimate description of things; but I certainly don't believe the ideas, like Bohm (nonlocal determinism) or Everett (many worlds), which try to make a finished objective theory by just adding an extra mathematical and metaphysical facade. The extra details they posit have a brittle artificiality about them. They do link up with genuine aspects of the quantum mathematical formalism, and so they may indirectly contribute to progress just a little, but I think the future lies more with the traditional view.

Is quantum physics actually an improvement in the theory of how reality works? Or is it just building uncertainty into our model of reality?

The Quantum Physics Sequence

On the first point: I try never to categorize questions as intelligent or dumb, but is quantum mechanics an improvement? Unquestionably. To give only the most obvious example, lasers work by quantum excitation.

I, too, would be interested in learning quantum mechanics from a good textbook.

Brain training, for those not following the link, refers to playing games involving particular mental skills (e.g. memory). The study ran six weeks.

I don't think the experiment looks definite - the control group did not appear as thoroughly distinguished from the test groups as I would have liked - but the MRC Cognition and Brain Sciences Unit (who were partners in the experiment) is well-regarded enough that I would call the null result major evidence.

The fact that they studied adults rather than children may make a difference.

The only way I know to track karma changes is having an old tab with my Recent Comments visible and comparing it to the new one. That captures a lot of the change - >90% - but not the old threads.

I would love to know how hard it would be to have a "Recent Karma Changes" feed.

"Forcibly rewritten" implies your being a different person afterwards. Naively, time consistency would suggest treating them as such.

Available without the paywall from the author's home page.

It's also an argument in favor of using checklists.

Cool. Since a handful of studies suggest a narrow majority believe moral responsibility and determinism to be incompatible this shouldn't actually be that surprising. I want to know how people act after being exposed to statements in favor of compatibilism.

it isn't all that likely to lead to a conclusion there's a God as commonly conceived

The Bayesian translation of this is "I'm an atheist".

While I'm on the subject, is there any reason to think Omega is possible? Or is Omega simply a handy tool for thinking about philosophical problems?

Interesting. I'm not sure I know enough about Omega to say. But for one thing: I think it is probably impossible for Omega to predict it's own future mental states (there would be an infinite recursion). This will introduce uncertainty into its model of the universe.

The justification for atheism over agnosticism is essentially Occam's Razor. As far as we know, there are no exceptions to physics as we understand it. So God/Gods explains nothing that isn't already explained by physics. So P(physics is true) >= P(Physics is true AND God/Gods exist(s))

I've always taken Omega to be just a handy tool for thinking about philosophical problems. "Omega appears and tells you X" is short for "For the purposes of this conundrum, imagine that X is true, that you have undeniably conclusive evidence for X, and that the nature of this evidence and why it convinces you is irrelevant to the problem."

In a case where X is impossible ("Omega appears and tells you that 2+2=3") then the conundrum is broken.

People have been worrying about that one since Malthus. Turns out, production capacity can increase exponentially too, and when any given child has a high enough chance of survival, the strategy shifts from spamming lots of low-investment kids (for farm labor) to having one or two children and lavishing resources on them, which is why birthrates in the developed world are dropping below replacement.

I had the rats learn that a light, a little flashing light in a Pavlovian box, is followed sometimes by a tone and sometimes by food.

The information here is a little scant. If, in the cases where there was a tone instead of food, the tone always followed very soon after the light, it'd be most logical for rats to wait for the tone after seeing the light, and only go look for food after confirming that no tone was forthcoming. (This would save them effort assuming the food section was significantly far away. No tone = food. Tone = no food. Or did the scientists sometimes have the light be followed by both tone and food? I assume no, because that would introduce a first-order Pavlovian association between tone and food, which would mess up the next part of the experiment.)

Then, at test, some of the rats got tone and they tended to go look in the food section.

If, as I suggested above, the rats had previously been trained to wait for the lack of a tone before checking in the food section, this result would more strongly rule out a second-order Pavlovian response.

The critical test was with another group of rats that got the same training. We gave them a lever that they had never had before. They were in this box, and they have a lever that is rigged so that if they press the lever the tone will immediately come up. ... In that case, the intervening rats, after hearing the tone of their own intervention, should not expect food. Indeed, they didn't go to food nearly as much.

On the one hand, this is really surprising. On the other hand, I don't see how rats could survive without some cause-and-effect and logical reasoning. I'm really eager to see more studies on logical reasoning in animals. Any anecdotal evidence with house pets anyone?

You can do better than frequentist approach without using the "magic" universal prior. You can just use a prior that represents initial ignorance of the frequency at which the machine produces head-biased and tail-biased coins. (dP(f) = 1df). If you want to look for repeating patterns, you can assign probability (1/2)(1/2^n) to the theory that the machine produces each type of coin on a frequency depending on the last n coins it produced. This requires treating a probability as a strength of belief, and not the frequency of anything, which is what (as I understand it) frequentists are not willing to do.

Note the universal prior, if you can pull it off, is still better than what I described. The repeating pattern seeking prior will not notice, for example, if the machine makes head biased coins on prime-numbered trials, but tailbiased coins on composite-numbered trials. This is because it implicitly assigns probability 0 to that type of machine, which takes infinite evidence to update.

BTW, I wish there is a "public drafts" feature on LessWrong, where I can make a draft accessible to others by URL, but not show up in recent posts, so I don't have to post a draft elsewhere to get feedback before I officially publish it.

I second this feature request.

ETA: I did not notice earlier Steve Rayhawk made the same comment.

I wish there is a "public drafts" feature on LessWrong

Seconded. See also JenniferRM on editorial-level versus object-level comments.

Agreed. I'll be investigating what it would take to implement that.

(Edit: interesting; draft folders are apparently private sub-reddits created when a user registers and admin'ed by that user.)

Why does the universe that we live in look like a giant computer? What about uncomputable physics?

Consider "syntactic preference" as an order on agent's strategies (externally observable possible behaviors, but in mathematical sense, independently on what we can actually arrange to observe), where the agent is software running on an ordinary computer. This is "ontological boxing", a way of abstracting away any unknown physics. Then, this syntactic order can be given interpretation, as in logic/model theory, for example by placing the "agent program" in environment of all possible "world programs", and restating the order on possible agent's strategies in terms of possible outcomes for the world programs (as an order on sets of outcomes for all world programs), depending on the agent.

This way, we first factor out the real world from the problem, leaving only the syntactic backbone of preference, and then reintroduce a controllable version of the world, in a form of any convenient mathematical structure, an interpretation of syntactic preference. The question of whether the model world is "actually the real world", and whether it reflects all possible features of the real world, is sidestepped.

It's not feasible to attempt to create a government which both perfect and self-correcting. I'm not sure if the same is true of FAI.

Let's not forget that the clever student will be indeed very surprised by a test on any day, since he thinks he's proven that he won't be surprised by tests on those days. It seems he made an error in formalizing 'surprise'.

(imagine how surprised he'll be if the test is on Friday!)

Why not give a test on Monday, and then give another test later that day? I bet they would be surprised by a second test on the same day.

not as an exercise for solving

...and yet...

Can the teacher fulfill his announcement?

Probably.

p(teacher provides a surprise test) = 1 - x^3
Where:
x = 'improbability required for an event to be surprising'

If a 50% chance of having a test that day would leave a student surprised he can be 87.5% confident in being able to fullfil his assertion.

However, if the teacher was a causal decision agent then he would not be able to provide a surprise test without making the randomization process public (or a similar precommitment).

My take on capital punishment is that it's not actually that important an issue. With pretty much anything that you can say about the death penalty, you can say something similar about life imprisonment without parole (especially with the way that the death penalty is actually practiced in the United States). Would you lock an innocent man in a cell for the rest of his life to keep 19 bad ones locked up?

Virtually zero chance of recidivism? True for both. Very expensive? Check. Wrongly convicted innocent people get screwed? Check - though in both cases they have a decent chance of being exonerated after conviction before getting totally screwed (and thus only being partially screwed). Could be considered immoral to do something so severe to a person? Check. Deprives people of an "inalienable" right? Check (life/liberty). Strongly demonstrates society's disapproval of a crime? Check (slight edge to capital punishment, though life sentences would be better at this if the death penalty wasn't an option). Applied disproportionately to certain groups? I think so, though I don't know the research. Strong deterrent? It seems like the death penalty should be a bit stronger, but the evidence is unclear on that. Provides closure to the victim's family? Execution seems like more definitive closure, but they have to wait until years after sentencing to get it.

The criminal justice system is a big important topic, and I think it's too bad that this little piece of it (capital punishment) soaks up so much of our attention to it. Overall, my stance on capital punishment is ambivalent, leaning against it because it's not worth the trouble, though in some cases (like McVeigh) it's nice to have around and I could be swayed by a big deterrent effect. I'd prefer for more of the focus to be on this sort of thing (pdf).

There is strong Bayesian evidence that the USA has executed one innocent man. http://en.wikipedia.org/wiki/Cameron_Todd_Willingham By that I mean that an Amanda Knox test type analysis would clearly show that Willingham is innocent, probably with greater certainty than when the Amanda Knox case was analyzed. Does knowing that the USA has indeed provably executed an innocent person change your opinion?

What are the practical advantages of death over life in prison? US law allows for true life without parole. Life in an isolated cell in a Supermax prison is continual torture -- it is not a light punishment by any means. Without a single advantage given for the death penalty over life in prison without parole, I think that ~100% certainty is needed for execution.

I am against the death penalty for regular murder and mass murder and aggravated rape. I am indifferent with regards to the death penalty for crimes against humanity as I recognize that symbolic execution could be appropriate for grave enough crimes.

Political questions like this are far removed from the kind of analysis you seem to want to apply. If it's you taking out a killer yourself that's one thing, but the question of whether to support it as a law is something entirely different. This rabbit hole goes very far indeed. Anyway, why would you care about the Constitution - you're not one of the signers, are you? ;-)

The more judicious question, I am coming to realize, isn't so much "Which of these two Standard Positions should I stand firmly on".

The more useful question is, why do the positions matter? Why is the discussion currently crystallized around these standard positions important to me, and how should I fluidly allow whatever evidence I can find to move me toward some position, which is rather unlikely (given that the debate has been so long crystallized in this particular way) to be among the standard ones. And I shouldn't necessarily expect to stay at that position forever, once I have admitted in principle that new evidence, or changes in other beliefs of mine, must commit me to a change in position on that particular issue.

In the death-penalty debate I identify more strongly with the "abolitionist" standard position because I was brought up in an abolitionist country by left-wing parents. That is, I find myself on the opposite end of the spectrum from you. And yet, perhaps we are closer than is apparent at first glance, if we are both of us committed primarily to investigating the questions of values, the questions of fact, and the questions of process that might leave either or both of us, at the end of the inquiry, in a different position than we started from.

• Would I revise my "in principle" opposition to the death penalty if, for instance, the means of "execution" were modified to cryonic preservation? Would I then support cryonic preservation as a "punishment" for lesser crimes such as would currently result in lifetime imprisonment?

• Would I still oppose the death penalty if we had a Truth Machine? Or if we could press Omega into service to give us a negligible probability of wrongful conviction? Or otherwise rely on a (putatively) impartial means of judgment which didn't involve fallible humans? Is that even desirable, if it was at all possible?

• Would I support the death penalty if I found out it was an effective deterrent, or would I oppose it only if I found that it didn't deter? Does deterrence matter? Why, or why not?

• How does economics enter into such a decision? How much, whatever position I arrive at, should I consider myself obligated to actively try to ensure that the society I live in espouses that position? For what scope of "the society I live in" - how local or global?

Those are topics and questions I encounter in the process of thinking about things other than the death penalty; practically every important topic has repercussions on this one.

There's an old systems science saying that I think applies to rational discussions about Big Questions such as this one: "you can't change just one thing". You can't decide on just one belief, and as I have argued before, it serves no useful purpose to call an isolated belief "irrational". It seems more appropriate to examine the processes whereby we adjust networks of beliefs, how thoroughly we propagate evidence and argument among those networks.

There is currently something of a meta-debate on LW regarding how best to reflect this networked structure of adjusting our beliefs based on evidence and reasoning, with approaches such as TakeOnIt competing against more individual debate modeling tools, with LessWrong itself, not so much the blog but perhaps the community and its norms, having some potential to serve as such a process for arbitrating claims.

But all these prior discussions seem to take as a starting point that "you can't change just one belief". That's among the consequences of embracing uncertainty, I think.

Standard response: politics is the mind-killer.

Personal response: I'm opposed to the death penalty because it costs more than putting them in prison for life due to the huge number of appeals they're allowed (vaguely recall hearing in newspapers / reports). I feel the US has become so risk-averse and egalitarian that it cannot properly implement a death penalty. This is reflected in the back-and-forth questions you ask.

I also oppose it on the grounds that it is often used as a tool of vengeance rather than justice. Nitrogen poisoning (I think that was the gas they were talking about) is a safe, highly reliable, and euphoric means of death, but the US still prefers electrocution (can take minutes), injection (can feel like the veins are burning from the inside out while the body is paralyzed), etc.

That said, I don't care enough about the topic to try and alter its use, whether through voting, polling, letters, etc, nor do I desire to put much thought into it. Best to let hot topics alone.

And after asking about Bayes, you should ask for math rather than opinions.

Sorry for ranting instead of answering your question, but "power laws emerge everywhere" is mostly bullshit. Power laws are less ubiquitous than some experts want you to believe. And when you do see them, the underlying mechanisms are much more diverse than what these experts will suggest. They have an agenda: they want you to believe that they can solve your (biology, sociology, epidemiology, computer networks etc.) problem with their statistical mechanics toolbox. Usually they can't.

For some counterbalance, see Cosma Shalizi's work. He has many amusing rants, and a very good paper:

Gauss Is Not Mocked

So You Think You Have a Power Law — Well Isn't That Special?

Speaking Truth to Power About Weblogs, or, How Not to Draw a Straight Line

Power-law distributions in empirical data

Note that this is not a one-man crusade by Shalizi. Many experts of the fields invaded by power-law-wielding statistical physicists wrote debunking papers such as this:

http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.21.8169

Another very relevant and readable paper:

http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.11.6305

You could try "Ubiquity" by Mark Buchanan for the power law stuff, but it's been a while since I read it, so I can't vouch for it completely. (Confusingly, Amazon lists three books with that title and different subtitles, all by that author, all published around 2001-2002.)

Introduce them to really cool, socially near, atheists. In particular, provide contact with attractive opposite-gender children who are a couple of years older and are atheists.

Possibly introducing them to some of the content in A Human's Guide to Words, such as dissolving the question, would lead them to theological noncognitivism. The nice thing about that as opposed to direct atheism is it's more "insidious" because instead of saying, "I don't believe" the kids would end up making more subtle points, like, "What do you even mean by omnipotent?" This somehow seems a lot less alarming to people, so it might bother the parents much less, or even seem like "innocent" questioning.

I wouldn't proselytize too directly - you want to stay on their (and their mother's) good side, and I doubt it would be very effective anyways. You're better off trying to instill good values - open-mindedness, curiosity, ability to think for oneself, and other elements of rationality & morality - rather than focusing on religion directly. Just knowing an atheist (you) and being on good terms with him could help lead them to consider atheism down the road at some point, which is another reason why it's important to maintain a good relationship. Think about the parallel case of religious relatives who interfere with parents who are raising their kids non-religiously - there are a lot of similarities between their situation and yours (even though you really are right and they just think they are) and you could run into a lot of the same problems that they do.

I haven't had the chance to try it out personally, but Dale McGowan's blog seems useful for this sort of thing, and his books might be even more useful.

I'm not speaking from experience here, but that doesn't stop me from having opinions.

I don't believe this is an emergency. Are the kid's lives being affected negatively by the religion? What do they think of what they're being taught?

Actually, this could be an emergency if they're being taught about Hell. Are they? Is it haunting them?

Their minds aren't a battlefield between you and religious school-- what they believe is, well not exactly their choice because people aren't very good at choosing, but more their choice than yours.

I recommend teaching them a little thoughtful cynicism, with advertisements as the subject matter.

Speaking as someone who is seeing that sort of thing happening on the inside, I'm really not sure how you should deal with it. Even teaching traditional rationality doesn't help if religion is wrapped up in their social identity. I myself was lucky, in that I never did believe in god. I almost believe that the reason I came through sane was my IQ, although I'm sure that cannot be entirely correct. Getting them to socialize with other children who don't believe in god, or if that's not possible, children who believe in very different gods might help. I would also suggest you introduce them to fiction with strong rationality memes - Eliezer's Harry Potter fanfic [edited, see below] is the kind of thing that might appeal to children, although it has too much adult material.

Teach them the basis of bayesian reasoning without any connection to religion. This will help them in more ways and will lay the foundation for later when they naturally start questioning religion. Also their parents wont have anything against it you merely introduce it as a method for physics or chemistry or with the standard medical examples.

Dangerous situation!

How do the parents feel about science and science fiction? I believe that stuff has good effects.

One thing to do is make sure the kids understand that the Bible is just a bunch of stories. My mom teaches Reform Jewish Sunday school and makes this clear to her students. I make fun of her for cranking out little atheists.

Teaching that the bible is a bunch of stories written by multiple humans over time is not nearly as offensive as preaching atheism. Start there. This bit of knowledge should be enough to get your young relatives thinking about religion, if they want to start thinking about it.

The causes of "too big to fail" are:

1. Corporate personhood laws makes it harder to punish the actual people in charge.

2. Problems in tort law (in the US) make it difficult to sue corporations for certain kinds of damages.

3. A large government (territorial monopoly of jurisdiction) makes it more profitable for any sufficiently large company to use the state as a bludgeon against its competitors (lobbying, bribes, friends in high places) instead of competing directly on the market.

4. Letting companies that waste resources go bankrupt causes short-term damage to the economy, but it is healthy in the long term because it allows more efficient companies to take over the tied-up talent and resources. Politicians care more about the short term than the long term.

5. For pharmaceutical companies there is an additional embiggening factor. Testing for FDA drug approval costs millions of dollars, which constitutes a huge barrier to entry for smaller companies. Hence the large companies can grow larger with little competition. This is amplified by 1 and 2, and 3 suggests that most of the competition among Big Pharma is over legislators and regulators, not market competition.

Disclosure: I am a "common law" libertarian (I find all monopolies counterproductive, including state governments).

Quite depressing. Makes me even less likely to have my kids educated in the states. I wonder how bad Europe is on that count? Is it really better here? It can be hard to tell from inside; correcting for the fact that most info I get is biased one way or the other leaves me with pretty wide confidence intervals.

22/7 gives "something like" something like 3.1427 ?!? Surely it is more like some other things that that!

It would have been even more frustrating had the protagonist not also been guessing the teacher's password. It seemed that the protagonist just had a better memory of what more authoritative teachers had said.

The protagonist was closer to being able to derive π himself, but that played no part in his argument.

AAAAAIIIIIIIIEEEEEEEE

BOOM

Melatonin. Also, getting my housemates to harass me if I don't go to bed.