All of PeterDonis's Comments + Replies

Relativity

Recommendation: Spacetime and Geometry

Author: Sean Carroll

This is an expanded version of Carroll's lecture notes on relativity, which he has used to teach courses and which are available for free online (see the "Lecture Notes" tab on the page linked to above). I find it to be an excellent introduction to the subject, which covers the mathematical tools used, the basics of the theory, and the most common applications, all in a straightforward fashion. I have recommended this text (or its corresponding lecture notes) many times on Physic... (read more)

Your R is actually the Ricci tensor, not the Riemann tensor. The Riemann tensor has four indices, not two. The Ricci tensor is formed by contracting the Riemann tensor on its first and third indices.

Whether that means 'out of the normal range' for any particular hormone, I don't know. Nobody seems to have the faintest idea what 'normal range' means for these things.

Yes, a better way to put it would be that the bloodstream levels of T3/T4 should be significantly higher when the person is treated and feels better than they were before treatment.

it should probably cause TSH suppression

That would be expected, yes.

What would be ideal would be to figure out the cause of the 'hormone resistance', and fix it, rather than trying to overwhelm it.

Yes,... (read more)

Ok, so the "hormone resistance" hypothesis is really something more like: the rate of some key reaction involving T3/T4 is being slowed down by some unknown factor; since we don't know what the factor is, we can't fix it directly, but we can increase the reaction rate by increasing the concentration of T3/T4 in the bloodstream to above normal levels, to compensate for the damping effect of the unknown factor.

This hypothesis makes an obvious testable prediction: that when people with CFS/etc. who are treated with thyroid extract feel better, the T... (read more)

I have a couple of questions about your hypothesis.

First, as I understand it, you are hypothesizing that there are people who have symptoms of CFS/etc. but normal blood levels of T3, T4, and TSH, who can nevertheless be helped by taking thyroid extract. And your hypothesized explanation for why these people are having symptoms of CFS/etc. is that, even though there are normal levels of T3 and T4 in their bloodstream, those hormones are not getting into their cells where they are actually needed. But if that is the case, how will putting more T3 and T4 into... (read more)

In this case, the Knighian uncertainty cancels out

Does it? You still know that you will only be able to take one of the two bets; you just don't know which one. The Knightian uncertainty only cancels out if you know you can take both bets.

Apologies for coming to the discussion very, very late, but I just ran across this.

If I saw no need for more power, e.g. because I'm already maximally happy and there's a system to ensure sustainability, I'd happily give up everything.

How could you possibly get into this epistemic state? That is, how could you possibly be so sure of the sustainability of your maximally happy state, without any intervention from you, that you would be willing to give up all your optimization power?

(This isn't the only reason why I personally would not choose wireheading, but other reasons have already been well discussed in this thread and I haven't seen anyone else zero in on this particular point.)

when it was realized in dath ilan that business cycles were a thing, the economists probably said "This is a coordination problem", the shadarak backed them, and the serious people got together and coordinated to try to avoid business cycles.

I think this is a feature of dath ilan, not a bug.

Among the serious questions, there are also some questions like this, where you are almost certain that the "nice" answer is a lie.

On the Crowne-Marlowe scale, it looks to me (having found a copy online and taken it) like most of the questions are of this form. When I answered all of the questions honestly, I scored 6, which according to the test, indicates that I am "more willing than most people to respond to tests truthfully"; but what it indicates to me is that, for all but 6 out of 33 questions, the "nice" answer was ... (read more)

Is that because you think it's necessary to Wei_Dai's argument, or just because you would like people to be up front about what they think?

(although of course I don't trust your rationality either)

I'm not sure this qualifier is necessary. Your argument is sufficient to establish your point (which I agree with) even if you do trust the other's rationality.

Sorry for the late comment but I'm just running across this thread.

demand for loans decreased and this caused destruction of money via the logic of fractional reserve banking

This is an interesting comment which I haven't seen talked about much on econblogs (or other sources of information about economics, for that matter). I understand the logic: fractional reserve banking is basically using loans as a money multiplier, so fewer loans means less multiplication, hence effectively less money supply. But it makes me wonder: what happens when the loan dema... (read more)

Sorry for the late comment but I'm just running across this thread.

Prices don't go up if all the new money just ends up under Apple Computer's proverbial mattress instead of in the hands of someone who is going to spend it.

But as far as I know the mainstream economists like the Fed did not predict that this would happen; they thought quantitative easing would start banks (and others with large cash balances) lending again. If banks had started lending again, by your analysis (which I agree with), we would have seen significant inflation because of the ... (read more)

Are there any theories about the mechanism involved here? I've done a fair bit of Googling about this but haven't found any discussion of underlying mechanisms, only the statistics. I know that CoQ10 is critical in the metabolic cycle that produces ATP, and therefore is involved in energy production everywhere in the body; but I'm not sure how to get from that to the specific result of lowering blood pressure (rather than something more general like "feel more energetic").

Sorry for the late comment, but I'm just running across this thread.

The question is not whether Google reinvests their producer surplus better than other monopolies. The question is whether Google reinvests their producer surplus more efficiently, i.e., for greater total benefit to society as a whole, than would all the consumers who would otherwise get that surplus as consumer surplus. That seems highly unlikely since the options for reinvestment open to even a large company like Google will cover a much smaller range of possibilities than the options ope... (read more)

Even if we had teleporters, would future Tyler Cowens be writing that they're not as innovative as the car - and would they be correct, in that a teleporter is just a more efficient way of solving a problem that cars and airplanes had already partially solved?

I don't think so, because there are threshold effects. For example, consider the airplane vs. the car: having airplane travel available doesn't just mean your trips are shorter; it enables many trips that otherwise would not even be considered, and therefore enables many kinds of activities that ot... (read more)

In this particular case, I agree with you that the weatherman is far more likely to be right than the person's intuitions.

However, suppose the weatherman had said that since it's going to be sunny tomorrow, it would be a good day to go out and murder people, and gives a logical argument to support that position? Should the woman still go with what the weatherman says, if she can't find a flaw in his argument?

The intelligent people are still humans, and can default to their intuition just like we can if they think that using unfiltered intuition would be the most accurate.

But by hypothesis, we are talking about a scenario where the intelligent person is proposing something that violently clashes with an intuition that is supposed to be common to everyone. So we're not talking about whether the intelligent person has an advantage in all situations, on average; we're talking about whether the intelligent person has an advantage, on average, in that particular ... (read more)

why should we stand by our intuitions disregard the opinions of more intelligent people?

Because no matter how intelligent the people are, the amount of computation that went into their opinions will be orders of magnitude smaller than the amount of computation that went into our intuitions, as a result of evolutionary processes operating over centuries, millennia, and longer. So if there is a conflict, it's far more probable that the intelligent people have made some mistake that we haven't yet spotted.

I am reminded of a saying in programming (not sure ... (read more)