the distinction between mechanical and thermal energy is in the mind
The high-school definition of temperature as "a measure of the average kinetic energy of the particles" (see the grandparent comment) actually erases that distinction as it defines temperature through kinetic (mechanical) energy.
Right, but we don't think of a tennis ball falling in a vacuum as gaining thermal energy or rising in temperature. It is "only" gaining mechanical kinetic energy; a high school student would say that "this is not a thermal energy problem," even though the ball does have an average kinetic energy (kinetic energy, divided by 1 ball). But if temperature of something that we do think of as hot is just average kinetic energy, then there is a sense in which the entire universe is "not a thermal energy problem."
When you go to GiveWell's Donate page, one of the questions is,
How should we use your gift? We may use unrestricted gifts to support our operations or to make grants, at our discretion:
And you can choose the options:
Grants to recommended charities
Unrestricted donation
I notice I'm reluctant to pick "Unrestricted," fearing my donation might be "wasted" on GiveWell's operations, instead of going right to the charity. But that seems kind of strange. Choosing "Unrestricted" gives GiveWell strictly more options than choosing "Grants to recommended charities" because "Unrestricted" allows them to use the money either for their own operations, or just send it to the charities anyway. So as long as I trust GiveWell's decision-making process, "Unrestricted" is the best choice. And I presumably do trust GiveWell's decision-making, since I'm giving away some money based on their say-so. But I'm nevertheless inclined to hit "Grants to recommended charities," despite, like, mathematical proof that that's not the best option.
Can we talk about this a little? How can I get less confused?
This is a good article making a valuable point. But this —
Temperature is sometimes taught as, "a measure of the average kinetic energy of the particles," because for an ideal gas U/N = (3/2) kBT. This is wrong, for the same reason that the ideal gas entropy isn't the definition of entropy.
— is a confusing way to speak. There is such a thing as "the average kinetic energy of the particles", and one measure of this thing is called "temperature" in some contexts. There is nothing wrong with this as long as you are clear about what context you are in.
If you fall into the sun, your atoms will be strewn far and wide, and it won't be because of something "in the mind". There is a long and perfectly valid convention of calling the relevant feature of the sun its "temperature".
An alternate phrasing (which I think makes it clearer) would be: "the distinction between mechanical and thermal energy is in the mind, and because we associate temperature with thermal but not mechanical energy, it follows that two observers of the same system can interpret it as having two different temperatures without inconsistency."
In other words, if you fall into the sun, your atoms will be strewn far and wide, yes, but your atoms will be equally strewn far and wide if you fall into an ice-cold mechanical woodchipper. The distinction between the types of energy used for the scattering process is what is subjective.
2312 by Kim Stanley Robinson, the author of Red/Blue/Green Mars (which I did not read).
The protagonist, Swan Er Hong, is probably the single most annoying character in recent memory, more so even than Catelyn Stark of GoT (in the books, not the show). Despite being 130 odd years old, she is mostly driven by impulses fitting for a 13 year-old. She is also bossy, short-tempered and not very smart. Whether this is intentional is not clear to me, probably not. Fitz Wahram, a diplomat, who is much more reasonable, is under her spell and often goes out of his comfort zone for her, with considerable risk to his life and health.
This book is a rare case where I wish for the main character to bite the dust already.
Oh, and the long scientific ruminations by the author, judging by the parts close my area of expertise, physics and quantum computers, are total rubbish.
I put down the book when it describes Swan's more stupid antics, and pick it up again when I have nothing else to read.
Whether this is intentional is not clear to me, probably not.
I think it was intentional -- other characters frequently remark on how dumb she is. My impression is that Swan's character was some kind of artistic/political statement by Robinson -- that the adventures of a screwed-up, clueless person are just as valid and meaningful as those of more traditional heroes, or something. I wasn't too impressed by this, but the book's worldbuilding was amazing and that made up for everything else.
Following the Phoenix is an absolutely excellent "single-/dual-point-of-departure spinoff" from HPMOR, starting from HPMOR's Chapter 81.
I have found it very good reading; it really feels very original-flavor, as if it's what Eliezer could have potentially chosen to write instead of the path he chose to take.
Wait a minute, there's such a thing as fan fiction of fan fiction? What a time to be alive.
When you get to a fork in the road, take it.
(I will keep doing this. I have no shame.)
Nonfiction Books Thread
I just finished Red Plenty by Francis Spufford, which I bought because of this review on Slate Star Codex. It was a thoroughly enjoyable and interesting mix of history and fiction about the Soviet Union in the late 1950's and early 1960's, when it was actually plausible to hope that politicians and scientists could get central planning right and build an economy that provided a first-world standard of living to everyone. (Spoiler alert) it doesn't work out, and Red Plenty gives you a good look at how and why it failed.
I'm not usually a person given to intense patriotic emotions; I don't get choked up when "The Star Spangled Banner" is played or anything. But as an interesting side effect of reading this book, I love America a lot right now. I'm in the mood of people who get off planes and kiss the ground.
Always go to other people's funerals; otherwise they won't go to yours.
Yogi Berra, on Timeless Decision Theory.
Why is it easier to keep from eating M&M's "on your own" and leverage that ability to motivate you to do work, than it is to keep doing work "on your own" in the first place?
I'm assuming because "don't eat undeserved M&Ms" is a clear, simple and binary rule - breaches are obvious, so there's not much of a temptation to rationalize them. "Work on my stuff" is broad and fuzzy and has plenty of room for excuses like "I'm a bit tired today", "I deserve to rest", "I'll do it tomorrow', etc.
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The high-school definition of temperature as "a measure of the average kinetic energy of the particles" (see the grandparent comment) actually erases that distinction as it defines temperature through kinetic (mechanical) energy.
I didn't read your comment carefully enough. Yes, we agree.