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by unusualmonkey 747 days ago
Yes, a large set of instances is more likely than a single instance (all things being equal).

However that doesn't mean that a sphere is any more or less likely than any specific other structure. It's an small but important distinction.

No, a pyramid shaped planet is not as likely to form as a sphere shaped pyramid. Definitionally a pyramid shaped planet is impossible.

1 comments

> However that doesn't mean that a sphere is any more or less likely than any specific other structure.

A shape/structure doesn't have an intrinsic probability. Your sentence is underspecified. Shape of what under what process?

In the context of the shape of galaxies, I think we can agree that if we found galaxies forming a shape like this sentence: "WE ARE COMING", everyone would freak out. So yeah, in this context, some shapes are more likely to form (randomly) than others.

> So yeah, in this context, some shapes are more likely to form (randomly) than others.

Again I think you are confused. Assuming random distribution, 'We Are Coming' is just as likely as any other similarly long structure to form. You just happen to care about that structure more than others - however that doesn't make it more or less likey to form.

That message, in morse code is .-- . / .- .-. . / -.-. --- -- .. -. --..

There are 200B to 2T galaxies in the obeservable universe. If you found lines of galaxies and interperated them as morse code, I'm sure you'd find some interesting words/phrases being said.

You'd expect that phrase in every 2^28 = 268,435,456 random 28 digit binary strings - which is not very many. Keep in mind a galaxy could be part of many, many strings (different index position, different orientation of string).

> Again I think you are confused. Assuming random distribution, 'We Are Coming' is just as likely as any other similarly long structure to form.

You are confused. How could we be back to square one? We've discussed it before. I'm not arguing that "WE ARE COMING" is more likely than, for example, "WE RAE COMING". Of course, they are as likely.

Suppose you have a machine that generates 15-char strings. Yes, "INTERCHANGEABLE" is as likely as "YSVQEPQVIGXOQSR" to come out—but that’s not the point. My point is that the probability of getting a proper English word is very unlikely. Most of the time, you'll get gibberish strings.

Also, I didn't say the sentence to be encoded in morse code. Instead, the galaxies form the literal shape of "W", "E", and so on. I hope you can see that in this case, it's borderline impossible to happen.

> My point is that the probability of getting a proper English word is very unlikely. Most of the time, you'll get gibberish strings.

Sure, but given a large enough sample both will likely exist. So the fact that one happens to be english should not surprise anyone nor does it suggest meaning.

> Also, I didn't say the sentence to be encoded in morse code. Instead, the galaxies form the literal shape of "W", "E", and so on. I hope you can see that in this case, it's borderline impossible to happen.

I used morse as its easy to reason about. There's no reason to think shapes are impossible - you just have to define what makes a shape and then look for patterns that match.

Humans have been finding patterns in clouds, stars and even toast since time immemorial.

https://svs.gsfc.nasa.gov/30505

You just don't understand probability, possibility and potential very well. Yes, you can get hung up where you are and we can argue semantics - the fact is that if I throw 1000 dice and get 1000 "1"s that is not the same as my being able to theoretically do that an equal % chance each throw.

The ring may be possible but, so far, it's the only example so despite being a potential random outcome of randomness, the sheer singularity of its existence proves it's incredibly low likelihood of occurrence - perhaps such a low % chance of actually occurring that it may be easier to believe that the ring had help in its formation, whatever that may be.

I'm not going to deny obvious things just bc they challenge my worldview - especially if I have to defend my viewpoint semantically

> Sure, but given a large enough sample both will likely exist.

This applies to every event with nonzero probabilities. What's your point?

> Humans have been finding patterns in clouds, stars and even toast since time immemorial.

I knew this—humans love finding patterns. But our discussion is not about that. It's about the very basic thing in probabilities, which is some event is not as likely to happen as others. This is so trivially true.

The probability of getting a proper English word from a random string generator is much less likely than the probability of not getting it. Thus, getting a proper English word should be surprising. It is as surprising as getting any string from a set of gibberish strings with the same cardinality of English vocabularies.

> So the fact that one happens to be english should not surprise anyone

What should surprise you, then? I'm surprised that we need to talk about this very basic thing three times.

> But our discussion is not about that. It's about the very basic thing in probabilities, which is some event is not as likely to happen as others. This is so trivially true.

Except that's not a given.

Any equally long random string is as likely as any other equally long random string.

Different length sets of random strings may differ in probability.

Finding what might appear to be meaningful structures in large data sets, e.g. shapes in 2T galaxies, doesn't inherently suggest anymore than chance.

When the entire class of things are unlikely given the number of observations. The odds that I personally may win the Jackpot are low but the odds that someone at sometime wins is very high. So me winning would surprise me but someone winning wouldn’t. Applying that rule to research and a lot of people are looking for something interesting in many domains not just this particular one.

Similarly finding any shape in a random set of points is much more likely than the odds of any one shape.

So you need to adjust for both things people are looked for correlations and the entire class of things that would notice not just the odds of what you happened to see. A random process you run spitting out a famous quote would be low, but you would also be surprised Pi is 3,14 or Pi is 3.14 etc etc.

Thus someone else hitting a random process and getting “To be or knot to be” is now looking at the odds that anyone anywhere would get something that’s close to something memorable which should actually be quite high.

TLDR; https://xkcd.com/882/