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Divers accidentally find a piece of the Challenger space shuttle

smithsonianmag.com

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Re: Divers accidentally find a piece of the Challenger space shuttle

#11

Post by skissane »

DieBruderBauer wrote: post #8
_yb2s wrote: post #6

Earlier quoted context omitted.

Counterintuitively, extremely unlikely events like this happen very often. The odds of a specific event like this are astronomically small, but there is an even more astronomically large number of different possible unlikely events. The sheer number of possible events is orders of magnitude greater than the odds of individual unlikely events, causing them to occur regularly. The universe is a really weird place, wher…

Imagine if you took the Everettian interpretation of Quantum Mechanics.

If it is true, doesn’t it follow that there are (very rare) universes where unlikely events happen so often that anyone in such a universe would effectively observe a different probability distribution of events?

The thing is, if the theory is true, how do we know we are not in such a universe? We can say it is extremely unlikely because they are very rare - but we say it is “unlikely” and “rare” because we assume the global (multiverse-wide) probability distribution is similar to the local (this universe) one - but isn’t that assumption effectively equivalent to the assumption that we are not in such a universe? An argument which begins by assuming its conclusion is not much of an argument.

However, if we can’t rely on that assumption, it seems in principle impossible for us to know what the global probability distribution is - how is that not a lethal blow to the entire theory?

Re: Divers accidentally find a piece of the Challenger space shuttle

#12

Post by daveslash »

jl6 wrote: post #5

What seems amazing is that it isn’t covered in more sand and sediment. It would take such a small thickness of covering to hide it from view forever.

I wonder if it could have gone through cycles of buried/uncovered? I don't know anything about the waters off Florida other than they experience periodic hurricane events.

Re: Divers accidentally find a piece of the Challenger space shuttle

#13

Post by TedDoesntTalk »

_yb2s wrote: post #6
wwwtyro wrote: post #2

The odds of this seem astronomically small.

Counterintuitively, extremely unlikely events like this happen very often. The odds of a specific event like this are astronomically small, but there is an even more astronomically large number of different possible unlikely events. The sheer number of possible events is orders of magnitude greater than the odds of individual unlikely events, causing them to occur regularly. The universe is a really weird place, wher…

Like separate rolls of a single dice, I thought the occurrence of one event has no affect on the probability of another?

Re: Divers accidentally find a piece of the Challenger space shuttle

#14

Post by vikingerik »

wwwtyro wrote: post #2

The odds of this seem astronomically small.

The odds of this group of people, on this day, finding this piece of the shuttle, are of course astronomically small.

The odds of some group out of millions of people, on some day out of ten thousand since the incident, finding some piece of debris out of thousands, are considerably higher.

This is the multiple-endpoints fallacy. You only notice the events that happened after the fact, you never notice everything that doesn't happen.

Re: Divers accidentally find a piece of the Challenger space shuttle

#15

Post by ckastner »

_yb2s wrote: post #6
wwwtyro wrote: post #2

The odds of this seem astronomically small.

Counterintuitively, extremely unlikely events like this happen very often. The odds of a specific event like this are astronomically small, but there is an even more astronomically large number of different possible unlikely events. The sheer number of possible events is orders of magnitude greater than the odds of individual unlikely events, causing them to occur regularly. The universe is a really weird place, wher…

> Counterintuitively, extremely unlikely events like this happen very often.

As the saying goes, "people win the lottery every day", and there are a lot of lotteries active on this planet.

Re: Divers accidentally find a piece of the Challenger space shuttle

#16

Post by _yb2s »

skissane wrote: post #11
DieBruderBauer wrote: post #8

Earlier quoted context omitted.

Imagine if you took the Everettian interpretation of Quantum Mechanics.

If it is true, doesn’t it follow that there are (very rare) universes where unlikely events happen so often that anyone in such a universe would effectively observe a different probability distribution of events? The thing is, if the theory is true, how do we know we are not in such a universe? We can say it is extremely unlikely because they are very rare - but we say it is “unlikely” and “rare” because we assume th…

If you insist on using old fashioned logic to reason when in a probabilistic universe where that kind of reasoning is only an approximation, you can say that the universes you are talking about don't exist. They are such a small fraction of possible universes, that you can safely 'know' you aren't in any of them without checking.

Re: Divers accidentally find a piece of the Challenger space shuttle

#17

Post by _yb2s »

TedDoesntTalk wrote: post #13
_yb2s wrote: post #6

Earlier quoted context omitted.

Counterintuitively, extremely unlikely events like this happen very often. The odds of a specific event like this are astronomically small, but there is an even more astronomically large number of different possible unlikely events. The sheer number of possible events is orders of magnitude greater than the odds of individual unlikely events, causing them to occur regularly. The universe is a really weird place, wher…

Like separate rolls of a single dice, I thought the occurrence of one event has no affect on the probability of another?

Indeed, but I think you might be misunderstanding what I said. Think of the universe as a nearly infinite number of dice rolls all independent and in parallel. Any possible rare combination of dice rolls will actually be happening constantly.

Re: Divers accidentally find a piece of the Challenger space shuttle

#18

Post by shawnz »

TedDoesntTalk wrote: post #13
_yb2s wrote: post #6

Earlier quoted context omitted.

Counterintuitively, extremely unlikely events like this happen very often. The odds of a specific event like this are astronomically small, but there is an even more astronomically large number of different possible unlikely events. The sheer number of possible events is orders of magnitude greater than the odds of individual unlikely events, causing them to occur regularly. The universe is a really weird place, wher…

Like separate rolls of a single dice, I thought the occurrence of one event has no affect on the probability of another?

The person you are replying to isn't saying anything about the probability of individual events. They are talking about the probability of at least one of many events occurring, which does change with the number of events being considered

Re: Divers accidentally find a piece of the Challenger space shuttle

#19

Post by kelnos »

TedDoesntTalk wrote: post #13
_yb2s wrote: post #6

Earlier quoted context omitted.

Counterintuitively, extremely unlikely events like this happen very often. The odds of a specific event like this are astronomically small, but there is an even more astronomically large number of different possible unlikely events. The sheer number of possible events is orders of magnitude greater than the odds of individual unlikely events, causing them to occur regularly. The universe is a really weird place, wher…

Like separate rolls of a single dice, I thought the occurrence of one event has no affect on the probability of another?

Right, but while it may only be a 1/6 chance that a single die roll will give you a six, rolling more and more dice eventually makes it a near-certainty that at least one will give you a six.
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