Cynic

So, NOT a mathematician here, not even close, just to get that out of the way. I was involved in a discussion on another board about making assumptions about causation based solely on correlations. I mentioned the well known and documented phrase that “correlation does not imply causation” and linked a couple articles to it. One person came back with something else and I have unfortunately lost the link he referenced but I remember that it led me to another article on Bayesian statistics which I thought, at the time, was related. I’m sorry I haven’t been able to locate the original reference. So, I’m not sure what to think since I don’t really understand what I’ve been reading relative to my question about correlation and causation. My view is that correlations might indicate a causal relationship but this can only be verified by properly controlled experiments where other possible causes are taken into account. An example might be in epidemiology where interesting correlations between a given disease and populations of certain insects are observed. Whether the insects actually cause the disease however is not proven until controlled experiments are performed. So, my question is, are there situations, in the physical world, where correlation may be said to prove causation without doing actual experiments to prove it? I would have said no but I am still wondering about it. If such situations are possible, could someone describe to me what real world conditions must exist to provide proof in the absence of conducting experiments?

Poor physicist that I am, it often seems to me that our understanding of the universe is not that great. We have these staggering paradoxes, wave/particle duality for example, that we can define in such ways as to manipulate them but it seems to me we have no intuitive understanding of the true nature of what's happening. We just have conventions of describing them in terms that do not reflect their true nature. It seems to me that there are number of these things in cosmology, particle physics, relativity, etc. that are simply beyond us. I don't picture us as clever enough to understand all that much. So, maybe we invented higher math to describe that which we don't really understand?

But does that negate the possibility of them being physical? He says in his talk, correct me if I misconstrue him, that the major portion of the mass of a proton is contained in the "empty space" between the subatomic particles. So it would seem there's mass, regardless of whether we try to detect it. Have patience, you're dealing with a biologist.

Isn't Lawrence Krauss in his talk about a Universe from Nothing making the case that virtual particles have mass, since he is saying that "nothing weighs something". Therefore shouldn't they be physical? https://m.youtube.com/watch?v=-EilZ4VY5Vs

Simple minded sort that I am, I always just assumed that if something like that happened, it would be a tasty snack for something else...which would not have been the case way back when. It does raise an interesting question though for me, if there was some sort of biogenesis still happening, it seems there would be a decent chance of it having different handedness, or is there something favoring the handedness of life as it is now?

Hello forum, I joined just now to post this question. I didn't see it on a quick search. I've been wondering about this for some time but I'm only on 2 other forums regularly, drag racing and shooting, and those were not exactly the kind of places to get much of a conversation going about my question. So, what I've wondering and I'd appreciate hearing thoughts on this, is the expectation of intelligent extraterrestrial life. I realize that a search for extraterrestrial life should necessarily be focused on that which is intelligent because it's more reasonable to assume that such life would create some sort of detectable signature. My question though is why should we assume that intelligence is that common and not just some evolutionary rarity of the highest order? If we look at the history of all life on earth, intelligence, of a kind detectable over interstellar distances, is vanishingly rare. If we define intelligence as the sign of some pinnacle of evolution, then we are indeed successful. However, there have been tremendously successful species that have had no need of highly evolved intelligence. If we measure success by planetary biomass, we're not really all that successful (although we're working hard at that). Anyway, given that intelligence does not need to be viewed as some sort of "end goal" of evolution, and given how exceedingly rare it's been in the history of life on our planet, why should we expect it to be the least bit common elsewhere? The universe might be teeming with life, just not the kind that makes iPads.