Comment author: satt 10 May 2013 10:05:09PM 0 points [-]

[EY quote on the covariance of physical law for a spinning body]

Edit: You are correct from a classical physics standpoint that if you are in a windowless room on a merry-go-round, you can tell whether the merry-go-round is standing still versus spinning at a constant speed.

As far as I can tell, what I'm saying holds even for non-spinning accelerating objects, and under quantum physics. According to QFT, a sufficiently sensitive thermometer accelerating through a vacuum detects a higher temperature than a non-accelerating thermometer would. This appears to be a way for a thermometer to tell whether it's accelerating without having to "look" at distant stars & such.

Comment author: nonplussed 14 May 2013 09:52:02PM 0 points [-]

Hm, I'm not sure the thermometer can conclude that it's accelerating from seeing the black body radiation. I think it's equivalent to there being an event horizon behind it emitting hawking radiation (this happens when you accelerate at a constant rate). The thermometer can't tell if it's next to a black hole or if it's accelerating. Could be wrong though, but I vaguely remember something along these lines.

Comment author: nonplussed 15 April 2013 09:36:24PM 4 points [-]

I like something with 'rationality' and 'less wrong' in it. I don't think it's helpful to have 'the sequences' in the title if an aim to to have non less-wrongers pick it up.

What are the odds of a physical book? Would make a great gift, and gifting an ebook still seems weird. I'm still undecided about whether I like my books made out of dead trees or not.

Comment author: Dmytry 06 April 2012 10:22:09AM *  8 points [-]

if it was a total utility maximizing AI it would clone the utility monster (or start cloning everyone else if the utility monster is super linear) edit: on the other hand, if it was average utility maximizing AI it would kill everyone else leaving just the utility monster. In any case there'd be some serious population 'adjustment'.

Comment author: nonplussed 14 April 2013 10:08:34PM 0 points [-]

You're all wrong — if the happiness of the utility monster compounds as the comic says, then you get greater happiness out of lumping it all into one monster rather than cloning.

Comment author: Nisan 11 April 2013 09:48:54PM 1 point [-]

Welcome! What do you think of the Born probabilities?

Comment author: nonplussed 12 April 2013 08:34:25PM *  2 points [-]

I haven't gone through any of the supposed derivations, but I'm led to believe that the Born rule is convincingly derivable within many worlds. I have a book called "Many Worlds? Everett, quantum theory and reality", which contains such a derivation, I've been meaning to read it for a while and will get around to it some day. It claims:

An agent who arranges his preferences among various branching scenarios—quantum games—in accordance with certain principles of rationality, must act as if maximizing his expected utilities, as computed from the Born rule.

Which I think is a nice angle to view it from. At any rate, the Born rule is a fairly natural result to have, since the probabilities are simply the vector product of the wavefunction with itself, which is how you normally define the sizes of vectors in vector spaces. So I'm expecting the argument in the book to be related to the criteria that mathematicians use to define inner products, and how those criteria map to assumptions about the universe (ie no preferred spatial direction, that sort of thing). Maybe if I understand it I'll post something here about it for those who are interested — I'm yet to see a blog-style summary of where the Born rule comes from.

At any rate it doesn't come from anywhere in the way we're taught quantum mechanics at uni, it's simply an axiom that one doesn't question. So any derivation, however assumption laden and weak would be an improvement over standard Copenhagen.

Comment author: ModusPonies 12 April 2013 02:33:32PM 7 points [-]

I'm pretty social and would love to meet more rationalist friends, but I have the perception that if I went to a meetup most people would be less extroverted than me, and it might not be much fun for me.

My experience at meetups has been pretty social. After all, meetups select for people outgoing enough to go out of the house in the first place. I'd encourage you to go once, if there's a convenient meetup around. The value of information is high; if the meetup sucks, that costs one afternoon, but if it's good, you gain a new group of friends.

Comment author: nonplussed 12 April 2013 08:16:31PM *  1 point [-]

meetups select for people outgoing enough to go out of the house in the first place

Excellent point, I know that effect makes a huge difference in other contexts, so that resonates with me. Ok, well I'll give it a shot. There are no meetups near where I am in Germany at the moment, but I'll be back in Melbourne later in the year where there seems to be some regular stuff going on.

Comment author: sixes_and_sevens 08 March 2013 11:24:40AM *  5 points [-]

Related: buy a small and reliable compass. Not a compass app for your phone, but an actual compass. GPS, your own spatial awareness, and reasonable assumptions about geography can all let you down, but north is always north.

Edit: I will now ruin the punchiness of this comment with an explanatory edit. I do a lot of walking around a large city. Google Maps is fairly reliable but leaves much to be desired. Establishing GPS location, battery consumption and occasional out-and-out wrongness are common bugbears, so I started trying to navigate without it.

The biggest problem I found was orienting myself. Surfacing from a subway stop only to have no idea which direction was which, I'd sometimes fall back to GPS just to check what direction I was facing (which Google Maps is really bad at anyway. Anyone who's ever done that "let's walk ten metres in this direction to see what way I'm pointing" thing will know what I mean. I played around with some compass apps, which are just as much of a pain as Google Maps. Eventually I just gave in and bought a compass.

Comment author: nonplussed 10 April 2013 11:32:41PM 0 points [-]

Surprised no ones mentioned this, but what's wrong with a phone compass app? They don't use GPS, they are actually measuring the local magnetic field, and they don't delay whilst 'getting a lock' or anything. And it's not like they use much battery power.

Agree that a compass is superior to GPS for orientation, but I'm not seeing why it can't be an app.

Comment author: nonplussed 07 April 2013 06:50:22PM *  11 points [-]

Hi everyone, I'm Chris. I'm a physics PhD student from Melbourne, Australia. I came to rationalism slowly over the years by having excellent conversations with like minded friends. I was raised a catholic and fully bought into the faith, but became an atheist in early high school when I realised that scientific explanations made more sense.

About a year ago I had a huge problem with the collapse postulate of quantum mechanics. It just didn't make sense and neither did anything anyone was telling me about it. This led me to discover that many worlds wasn't as crazy as it had been made out to be, and led me to this very community. My growth as a rationalist has made me distrust the consensus opinions of more and more groups, and realising that physicists could get something so wrong was the final nail in the coffin for my trust of the scientific establishment. Of course science is still the best way to figure things out, but as soon as opinions become politicised or tied to job prospects, I don't trust scientists as far as I can throw them. Related to this is my skepticism that climate change is a big deal.

I am frustrated more by the extent of unreason in educated circles than I am in uneducated circles, as people should know better. For example, utilitarian morality should be much more widespread in these circles than it is. But moral issues are often politicised, and you know what they say about politics here.

I'm pretty social and would love to meet more rationalist friends, but I have the perception that if I went to a meetup most people would be less extroverted than me, and it might not be much fun for me. Also since I do physics and am into heavy metal, my social circles at the moment are like 95% male, and it seems pretty silly to invest effort in developing a new social group unless it does something about that number, which I'm pretty sure less wrong meetups will not. So I'm probably not going to look into this, even though I enjoy the communities writings online.

Though I find the writing style to sometimes be a bit dense and not self contained (requiring reading a lot of past posts to make sense of.) I find myself preferring the writing style of a rationalist blog like slatestarcodex (or its previous incarnation), and if the same issue is being discussed in two places I'll generally read it there instead because I prefer the more casual writing style.