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andyM1998
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Or get so close that human life will be destroyed
andyM1998 said:Or get so close that human life will be destroyed
BobG said:It's remotely (very, very remotely) possible.
It's far more likely that the Sun would expand large enough that all human life will be destroyed. In fact, the only thing that makes it unlikely is the chances of any species currently on Earth (including us) surviving long enough to still be around when the Sun does expand.
mathman said:That won't happen until several billion years from now. I suspect that intelligent life (if it survives global warming) will have figured out how to deal with it.
ModusPwnd said:I think that its less than a billion until the sun manages to evaporate away the oceans (~700 million IIRC). That could kill human life on Earth before the sun engulfs the earth.
mathman said:I can't dispute your time estimate. However, the point I am making is that homo sapiens has be around for around 200,000 years. Current technology has been around on the order of about one or two centuries. A few hundred million years is enough time to plan for the demise of the earth.
BobG said:While calculating average species lifetime is an inexact science, the average lifetime for any species is about 5 to 10 million years. The average lifetime for mammalian species is around 1 million years.
Humans probably won't be around. But if there is some other intelligent species around, they'd either have to rely on knowledge being passed across species somehow, or would have much less than a few hundred million years to develop their plans.
(The problem of how to pass knowledge down the years through multiple species or at least would be available and likely discovered by a future species would be kind of interesting.)
BobG said:While calculating average species lifetime is an inexact science, the average lifetime for any species is about 5 to 10 million years. The average lifetime for mammalian species is around 1 million years.
Given how much smaller the asteroid would likely be, and the fewer consequences it would have to life on Earth, it probably makes more sense to concentrate our attention on moving the asteroid rather than the Earth.bahamagreen said:I read something a long time ago that suggested the Earth could be temporarily moved out of and back into orbit in order to avoid an asteroid by igniting the equatorial region of a continent or maybe an ocean for about 12 hours (using much of the worlds' nuclear arsenal to do so).
Not to mention the possibility of intelligently designed evolution. By that I mean, if we ever have the technology to deal with the Sun changing, we would almost certainly have the technology to drastically effect the human genome, most likely to the extent that whatever existed by then might not be considered "human" by our present standards.ModusPwnd said:But some species go extinct because they continue to evolve, not because they die off. I wish the wikipedia went into this distinction because I would like to know more about it. Considering that human can thrive in just about every climate there is on Earth and that we are evolving faster than ever I think its a real possibility that when we go extinct its because we evolve into other animals rather than just dying off.
Humans are certainly not an average species. We are so different from all other species that it is pointless to look at other species in terms of the expected lifetime.BobG said:While calculating average species lifetime is an inexact science, the average lifetime for any species is about 5 to 10 million years. The average lifetime for mammalian species is around 1 million years.
The effect would be completely negligible. I would be surprised if you would gain a millimeter or even a meter.bahamagreen said:I read something a long time ago that suggested the Earth could be temporarily moved out of and back into orbit in order to avoid an asteroid by igniting the equatorial region of a continent or maybe an ocean for about 12 hours (using much of the worlds' nuclear arsenal to do so).
BobG said:While calculating average species lifetime is an inexact science, the average lifetime for any species is about 5 to 10 million years. The average lifetime for mammalian species is around 1 million years.
Humans probably won't be around. But if there is some other intelligent species around, they'd either have to rely on knowledge being passed across species somehow, or would have much less than a few hundred million years to develop their plans.
(The problem of how to pass knowledge down the years through multiple species or at least would be available and likely discovered by a future species would be kind of interesting.)
Exactly, that's why we know the expectation value must be $100, so any calculation that gets a different result is incorrect.bahamagreen said:If this was a game in which after each selection one was allowed to "buy" the other envelop with the money you got from your selection, your strategy would be to always do so... kind of a paradox if you see the initial selection as random.
The statement may be taken to be true. However, you are certainly right that an important part of the story are unseen correlations. In other words, we cannot hold that this is the only relevant information-- but all other relevant information is withheld from us. The same is true of the "Doomsday Argument"-- just because relevant information is unavailable to us, it does not mean we can assume it does not exist. One cannot always get away with that assumption when doing probability calculations, such as the claim that there is a 95% chance that we are not in the first 5% of all humans, given that we know our birth number is about 10 billion or so.One the other hand, there may be a problem with assuming too much about the phrase "one has twice the money in it as the other"...
Right, one does not know how to do that, which is why one gets an incorrect calculation of an expectation value if one makes certain unjustifiable assumptions. The only justifiable assumption is the symmetry principle that neither envelope is more likely to be worth more, so the other envelope must have a statistical value equal to what is revealed in the first. If you would buy the second envelope for any more than that, you will always lose money in the long run, no matter what system is used to stuff the envelopes.I guess what I'm thinking is that if a particular stipulation is only one of many that achieve the same relation, what is the basis for extending that particular relation to yield the hypothetical case values?
The selection isn't in time, it is in birth order. So it is normal to assume that all individuals are distributed evenly over birth order, that is, a randomly selected human from the full population is equally likely to have any birth number from 1 to N, where N is the total number of humans who ever live. But when we know that we are number 10 billion, say, we can no longer claim to be evenly distributed. That's the fallacy of mistaking an unknown correlation for a nonexistent correlation. It doesn't matter how the birth order maps into the time dimension, that's a separate issue that does not relate to the error in the argument (it brings in additional uncertainties, like assumptions about how the human population will wax or wane with time, but the argument is already wrong before it even gets to that point). It is just wrong to say that "since I don't know how my birth number correlates with where I stand in the total population, I may assume there is no correlation." The same error leads to the wrong expectation value for the second envelope.bahamagreen said:It seems to me that if the selection is of a random time within the interval, then all times are equally probable and the attaching of a human to that time is incidental or independent; but if it is the selection of a human that is being done from within the total historical population in the interval, then the corresponding time location for that human is going to be more likely in the population dense direction of the time interval.
Yes, I have no idea on what basis they make that claim. For example, they also state (note N1 = 60 billion and N2=6,000 billion, and X is the 59+ billionth human):bahamagreen said:So Wiki is incorrect when it states that, "f is uniformly distributed on (0, 1] even after learning of the absolute position n." ?
This argument is a strawman, it only works for certain types of distributions (here it assumes humanity has a 50% chance of going extinct after 60 billion humans are born, which is pretty much already assuming what it is claiming to prove). To destroy the argument, all I have to do is choose a different distribution, where humanity has a 99.99% chance of having 6,000 billion humans born before going extinct, and a 0.01% chance of going extinct after 6 billion. Now if I imagine a vast number of different species, all over the universe, that obey this exact same longevity distribution, and I select a member at random from each of those species, and I restrict to the tiny subclass of those random selections in which I got a 59+ billionth member, then I can simply ask-- how many of those civilizations will last to 6,000 billion members? That calculation is easy-- 99.99% of the time I will select from a 6,000 billion member species, and 1/6000 of those I will get someone in the 59+ billionth bin (the bin is a billion people wide), for a grand total of about 1/6000 of the species I sampled. Also, 0.01% of the time I will select from a 60 billion member species, and 1/60 of those will give me someone in the 59+ billionth bin, for a grand total of 1/600,000 of the time. Comparing these frequencies tells us that 99% of the time, my 59+ billionth member, randomly selected from the full population, is part of a 600 billion member species. This refutes the claim of the Wiki article, which holds that we can infer things about the longevity distribution without first assuming anything about it, and that's pretty obviously wrong.Wiki on Doomsday Argument said:Now, if we assume that the number of humans who will ever be born equals N1, the probability that X is amongst the first 60 billion humans who have ever lived is of course 100%. However, if the number of humans who will ever be born equals N2, then the probability that X is amongst the first 60 billion humans who have ever lived is only 1%. Since X is in fact amongst the first 60 billion humans who have ever lived, this means that the total number of humans who will ever be born is more likely to be much closer to 60 billion than to 6,000 billion.
Right.Ken G said:The Doomsday Argument is a logical fallacy.
That's another issue, it's harder to say what significance that has. The way it is usually framed is, yes 10% would get it wrong, but there's still only a 10% chance we are among those. I'm saying that if we already know our birth number is 59+ billion, we can not still say that we have a 10% chance of being among those that got it wrong.mfb said:Right.
The first 5% and the last 5% would always get it wrong.
Right, we cannot assume correlations don't exist just because we don't know what they are. If we don't use our own birth number, we can treat ourselves as "generic humans", but as soon as we do, we can no longer think we are generic.A proper analysis would need Bayesian statistics here, but we have no idea how a proper prior would look like*, so we cannot make probability calculations based on the number of humans that lived on Earth so far.
goldust said:Only if an asteroid causes another planet's orbit to change, pulling Earth out of its orbit and possibly plunging Earth into the Sun, or hitting the Earth itself and altering Earth's orbit to the same effect.
While the Earth's orbit can change slightly due to various factors such as gravitational pull from other planets, it is highly unlikely that it will cause the Earth to crash into the sun. The Earth's orbit is very stable and any changes would be gradual and not large enough to cause such a catastrophic event.
If the Earth's orbit were to suddenly shift towards the sun, it would have devastating consequences for all life on Earth. The intense heat and radiation from the sun would make the planet uninhabitable and all life forms would perish.
While there are natural factors that can affect the Earth's orbit, such as the gravitational pull from other planets, the most likely scenario for a drastic orbit change would be a collision with a large celestial object. However, the chances of such an event occurring are extremely low.
Scientists continuously monitor the Earth's orbit through various methods such as satellite observations and mathematical calculations. This helps to track any changes and ensure that the orbit remains stable.
No, human activity does not have the capability to significantly alter the Earth's orbit and cause it to crash into the sun. While human actions can have an impact on the environment and climate, they do not have the power to change the Earth's orbit in a significant way.