Science questions not worth a thread I: I'm a moron!
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It's somewhat disappointing answer, but apparently the best one there is, so thanks! 
Uppi: Ok, that's good enough. I had thought the whole idea wrong, like the error was an estimate to what the real value of the investigated thing is, although apparently it should just be thought as "here's the standard deviation, do what you will with it".
It of course makes sense, since the people who read the papers know what they're doing. It does cause some confusion in the undergrad labs though. People for example think that their measurements must've been off if the real value doesn't go in the one-SD interval.
Do you mean Student's T-distribution? That's what I've thought you'd use if you have too few measurements with normal error, but they're easily described with the number of measurements. Or do you use something more exotic? I've heard that some other distributions are needed in modern physics too, but wasn't sure if that was for error handling or just part of the theory (e.g. Maxwell-Boltzmann distribution).
Uppi: Ok, that's good enough. I had thought the whole idea wrong, like the error was an estimate to what the real value of the investigated thing is, although apparently it should just be thought as "here's the standard deviation, do what you will with it".
It of course makes sense, since the people who read the papers know what they're doing. It does cause some confusion in the undergrad labs though. People for example think that their measurements must've been off if the real value doesn't go in the one-SD interval.
Do you mean Student's T-distribution? That's what I've thought you'd use if you have too few measurements with normal error, but they're easily described with the number of measurements. Or do you use something more exotic? I've heard that some other distributions are needed in modern physics too, but wasn't sure if that was for error handling or just part of the theory (e.g. Maxwell-Boltzmann distribution).
Well, your best estimate what the real value is should go as the actual value you give. Ideally, you would want the entire probability distribution of possible values along with that, but most of the time nobody wants to waste space for that. Sometimes the standard deviation is to be understood as "we think the real value described by a normal distribution with mean x and variance y", but as I said that is not always the case. So "here's the standard deviation, do what you will with it", is indeed the correct interpretation.
I guess that is what undergraduate labs are for. I think error estimation is a bit unfair on the undergraduates, because they're told to follow a recipe without explaining them what they are actually doing. But by following the recipe they are at least capable of producing a reasonable number (except those who are going to be theorists, of course).
The Student's T-distribution still assumes sampling a normal distribution. However, there is no reason to assume that you are sampling such a distribution. This is especially the case when dealing with a small number of discrete events, where you know that the normal distribution does not apply and you need to go for a Poisson distribution or even a binomial distribution.
Ok. Would an example of e.g. Poisson distribution be observing neutrinos in those underground water pools they have for that purpose?
Yes, I think so.
Timsup2nothin
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Curiosity about ants...
The reproduction in an ant colony is handled by the queen and certain winged males...great. If the colony is destroyed the members of the colony would apparently be doomed...also great, unless you are an ant.
But, let's say we have an individual ant out exploring/foraging/ whatever. Obviously he isn't really alone, there are plenty of these foragers. So, what happens to them when the colony is destroyed? I read that the lifespan of a black garden ant is fifteen years (!) but it specified that they were talking about the queen. Would these wayward foragers just wander around for years? Expatriate nomads?
The reproduction in an ant colony is handled by the queen and certain winged males...great. If the colony is destroyed the members of the colony would apparently be doomed...also great, unless you are an ant.
But, let's say we have an individual ant out exploring/foraging/ whatever. Obviously he isn't really alone, there are plenty of these foragers. So, what happens to them when the colony is destroyed? I read that the lifespan of a black garden ant is fifteen years (!) but it specified that they were talking about the queen. Would these wayward foragers just wander around for years? Expatriate nomads?
I believe worker ants have typical lifespans of around one year, although there could be species with longer worker lifespans. Queens can live 15-25 years depending on the species. I googled this and what I'm finding suggests that ant colonies with no queen keep on going for a while just like before, but no new ants are born to replace the ones that die off, so the colony withers and dies out in around a year. Species that have multiple queens create colonies that can last longer and can create new queens that stay in the colony, although as with most species, most virgin queens fly off to mate and then start new colonies. In a few species, workers can become fertile and start laying more worker eggs by cloning themselves rather than through sexual reproduction, so I assume those can last longer after the queen dies.
Lohrenswald
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I'm pretty sure those fertile worker ants are called gamergates
They are actually. Someone needs to start a thread on the gamergate controversy. 
Timsup2nothin
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Thanks Boots!
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http://arstechnica.com/science/2016...n-an-abandoned-polish-nuclear-weapons-bunker/
I read this just yesterday, they recently found an ant colony sitting on top of an airvent to an abandoned soviet nuclear bunker. Each year thousands of worker ants fall in and can't get back up, this has resulted in an independent, queenless, reproductionless colony that has lasted for decades in total darkness and isolation. Pretty interesting! I wonder if they would ever form similar colonies in the wild and just wait for a lost queen to wander through and join them.
I read this just yesterday, they recently found an ant colony sitting on top of an airvent to an abandoned soviet nuclear bunker. Each year thousands of worker ants fall in and can't get back up, this has resulted in an independent, queenless, reproductionless colony that has lasted for decades in total darkness and isolation. Pretty interesting! I wonder if they would ever form similar colonies in the wild and just wait for a lost queen to wander through and join them.
Timsup2nothin
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Wow. And I was feeling bad for this lone ant living in my kitchen window.
Lohrenswald
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Why doesn't Venus or Mars have magnetic fields?
Short answer: Nobody knows exactly.
Longer answer: For a rocky planet to generate a magnetic field it needs to fulfill at least three conditions: It needs to rotate, it needs a (partially) liquid core, and it needs thermal convection in the core. Mars and Venus both rotate, Venus definitely has a molten core, and the core of Mars is also theorized to be molten (I do not know, whether that has been decided yet, some of the Mars rovers were supposed to give insight into this). What both seem to lack is thermal convection in the core. Both seem to have had that in the past, so the question is: Why did it stop? I haven't found a satisfying answer for that.
Last I heard about it, the models for the geodynamo are not very good even for earth so it is very hard to extrapolate to other planets, where we have much less accurate measurements. Additionally, when surveying just the solar system, we have a small sample size with no clear pattern. Pinpointing the exact cause would probably require a survey of many exoplanets, which might be far away in the future.
Timsup2nothin
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What I've heard as the most likely explanation for that is a lack of tidal forces to increase the effects of convection. Venus has no satellite of any consequence and is almost tidally locked to the sun. Mars is farther from the sun and the two moons are tiny compared to ours.
Possible, but Ganymede has no satellite and is tidally locked to Jupiter, yet generates a magnetic field. That explanation is not convincing enough for me.
Edit: Mercury is actually the more obvious counterexample: tidally locked with the sun and no moon, but generates a magnetic field.
Lohrenswald
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Yea, when I heard Mars didn't have a magnetic field, I was kinda guessing Venus would have one, while Mercury didn't, but the opposite was true.
The reason I asked specifically about Mars and Venus was because they are the only two planets in the solar system without one, I did infact read the wikipedia article before asking.
Thermal convection in the core you say? Sounds kinda interesting. Feels kinda odd Mercury would have it but not Mars or Venus.
Although IIRC there was something about Mercury's core being almost ridiculously large.
But I shan't nag too much if there isn't like a decisive answer or what have you.
But on the topic of planets, I've heard something along the lines of "Mars isn't geologically active"
So like no plates and mantle motion like on earth I take that too mean.
Is there like any theory on why this is for Mars? And how is it on other planets?
The reason I asked specifically about Mars and Venus was because they are the only two planets in the solar system without one, I did infact read the wikipedia article before asking.
Thermal convection in the core you say? Sounds kinda interesting. Feels kinda odd Mercury would have it but not Mars or Venus.
Although IIRC there was something about Mercury's core being almost ridiculously large.
But I shan't nag too much if there isn't like a decisive answer or what have you.
But on the topic of planets, I've heard something along the lines of "Mars isn't geologically active"
So like no plates and mantle motion like on earth I take that too mean.
Is there like any theory on why this is for Mars? And how is it on other planets?
I seem to recall Ganymedes field is a remnant magnetization of it passing through Jupiters field.
Timsup2nothin
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While Ganymede doesn't have a satellite of it's own one would think that interaction with other satellites of Jupiter could serve to stir up currents in its core.
Mercury is certainly a good example though.
How about a different parallel circumstance for the unique case there, in that being so close to the sun and tidally locked creates added convection forces in temperature differential across the surface. Not that the surface is involved in a liquid sense, but there could be heat transferred through the core from the hot side to the cold, especially in the absence of atmosphere to do that job.
So Venus not only lacks a satellite to stir up tidal forces but the close proximity and lack of atmosphere to have the sun driving added convection through the core that Mercury has.
Conjecture, purely, but it seems reasonable to me.
Alternately, we have four rocky planets, two have magnetic fields and two don't...this is random.
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