This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
I was into dinosaurs when I was a kid, and now I'm teaching my kids about dinosaurs. In light how much our understanding of dinosaurs has drifted in 30 years, and after learning about how certain dinosaurs species are basically extrapolations based on, like, a single bone, I'm trying to get a sense of what we actually know about dinosaurs versus what is just being made up to fill in the gaps.
As an example of what I'm talking about, the wing span for quetzalcoatlus keeps being revised downward. They seem to have a few skeleton fragments, and then they extra... (read more)
Once in a while I read somewhere online an article that tells people not to worry about sexually transmitted diseases, because they are rare, and most of them can be easily cured by antibiotics anyway, so the dangers of having a lot of sex with random people are exaggerated. (And then the article often becomes political and starts explaining why the bad guys -- the conservatives -- want to scare you into having less happiness in your life. Because they are stupid and evil, duh.)
How realistic is this? The argument about frequency of diseases in population i... (read more)
My possibly stupid question is: "Are some/all of LessWrong's values manufactured?"
Robin Hanson brings up the plasticity of values. Humans exposed to spicy food and social conformity pressures rewire their brain to make the pain pleasurable. The jump from plastic qualia to plastic values is a big one, but it seems plausible. It seems likely that cultural prestige causes people to rewire things like research, studying, etc. as interesting/pleasurable. Perhaps intellectual values and highbrow culture are entirely manufactured values. This seems mild... (read more)
Why can I hear noise (white noise / pink noise / brown noise), but not hear temperatures?
EDIT FOR CLARIFICATION Air temperature is caused by air molecules moving randomly at high speed, white noise is caused by air molecules moving randomly at high speed, what's the difference? Why does white noise fill the room with sound instead of just raising the temperature slightly?
My hand-wavy-sounds-like-science-technobable guess is that temperature does fill the air with sound, but most of the energy of that sound is at far too high frequencies for my eardrums to... (read more)
You can't hear temperatures because if the temperatures of air were high enough to make enough noise for you to hear, you would be incinerated.
http://physics.stackexchange.com/questions/110540/how-loud-is-the-thermal-motion-of-air-molecules goes over this. There is a lot of error in that thread, but the parts that are right show up a few times and calculate the white noise sound level of room temperature air at about -20 dB SPL. SPL of 0 dB is the approximate threshold of human hearing. dB is a logarithmic scale such that every 10 dB increase is a 10X higher power. So -20 dB SPL is about 1/100 the average sound power level that would just barely be audible by a human. This is calculated at something close to room temperature, about 23 C which is about 300 K.
How hot would air have to get to have its thermal fluctuations audible as sound to humans? Any thermal power (at sufficiently low frequencies which situation applies here) is proportional to the temperature. So to increase the thermal sound level from -20 dB to 0 dB, the sound power needs to be increased by a factor of 100. So this would happen at an absolute air temperature of 30000 K, or about 29700 C. For us Amer... (read more)
Repeating my question from late in the previous thread:
It seems to me that if you buy a stock, you could come out arbitrarily well-off, but your losses are limited to the amount you put in. But if you short, your payoffs are limited to the current price, and your losses could be arbitrarily big, until you run out of money.
Is this accurate? If so, it feels like an important asymmetry that I haven't absorbed from the "stock markets 101" type things that I've occasionally read. What effects does it have on markets, if any? (Running my mouth off, I'd... (read more)
It gets very interesting if there actually are no stocks to buy back in the market. For details on how it gets interesting google "short squeeze".
Other than that exceptional situation it's not that asymmetrical:
-Typically you have to post some collateral for shorting and there will be a well-understood maximum loss before your broker buys back the stock and seizes your collateral to cover that loss. So short (haha) of a short squeeze there actually is a maximum loss in short selling.
-You can take similar risks on the long side by buying stocks on credit ("on margin" in financial slang) with collateral, which the bank will use to close your position if the stock drops too far. So basically long risks also can be made as big as your borrowing ability.
I'm not a biologist, but am I right in thinking that Crispr could be the most important human innovation ever? This Wired article claims that a knowledgeable scientists thinks that the "off-target mutations are already a solved problem." Within a decade we should know a lot about the genetic basis of intelligence. Wouldn't it then probably be easy to create embryos that give birth to extremely smart people, far smarter than have ever existed?
When people get dizzy from spinning around, they sometimes spin the other way to get less dizzy. My default reaction is, no way that can actually work.
So, does it work?
(I remember trying inconclusively to research this.)
When, if ever, is playing computer games good for me?
Why don't ordinary photons spontaneously collapse into black holes? You should get a singularity if the energy density in any region of space is high enough. But you can pick an inertial reference frame such that any given photon has arbitrarily high frequency (and thus energy) due to blueshift. Since any inertial reference frame is as valid as any other due to relativity, why don't all photons collapse under their own weight?
I gave my book to my dad and I noticed him licking his finger to turn pages. I exploded and took the book away from him. I apologized later and explained this annoys me to no end.
Can anyone explain why people do it? FWIW I occasionally had two page turn at once and very rarely three at ones. I'm guessing it's something with the ink, just to make my head work a bit. Or perhaps something to do with older books. Can anyone explain why people do this? I ran a search and I only got even more questions, like if it spreads germs.
(My dad said he always did it, so he's rather unhelpful too)
I commisioned a 99designs logo and bought the corresponding domain name. The logo and domain name are pretty bad. It was a stupid decision I made months ago. It's a sunk cost. What happens now? Should I just sit on these? Sell the domain and just forget about the logo. The logo I chose is such that I probably could have made a better one myself in half an hour and the domain name isn't inherently valuable.
Why shouldn't I just publish all my identity documents on Facebook?
My immediate thought is: 'identity theft!' and 'that's illegal'.
But now that I'm trying to evaluate the evidence for the first and the second, it's hard to find any hard indications of either .
Are there records of anyone publishing all their identity documents online?
Are there any stories attached to these, or accounts of the consequences?