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Space Math Academy

space-math.academy

21–26 of 26 posts

Re: Space Math Academy

#21

Earlier quoted context omitted.

To be honest I do not think that these word games are helpful at all. Throughout all of my mathematical education what has always helped me to keep my "mental workspace clean", was to never abandon the model. > and correctly taxonomising those propositions The correct taxonomy for a proposition is true/false and proven/unproven. I can not even fathom a mathematical model where distinguishing a "law" from a "fact" is…

I dislike the linked site. A lot. But counterpoint: Zermelo-Frankel with or without Axiom of Choice is a fair mathematical analogue to distinguishing laws and facts, in my opinion. Put another way, decidability is a large area of mathematical research.

>Put another way, decidability is a large area of mathematical research.

What does ZF(C) have to do with decidability? Decidability is a question in any sufficiently complex system (Gödel's first theorem). And exactly this distinction is what I made for the taxonomy of propositions, you can group them into true and false and also into provable and unprovable. What would be a fact and what would be a law?

Regardless of that, in neither case the empiricism the site uses to define a fact would play any role.

Re: Space Math Academy

#24
post #12

Earlier quoted context omitted.

There are photos of the Earth taken from the neighborhood of the Moon. They show something that is indistinguishable from a sphere to the naked eye. Sure, with instruments you can measure it and find that it deviates from a perfect sphere. But every object that is made of atoms multiple atoms is not a perfect sphere.

I don't think it's a pedantic point, this is supposed to be a site about learning math that NASA scientists use, and the exact shape of the Earth is very relevant to them. I just think it shouldn't be used as a canonical example of a fact when you'll probably learn at some point that it technically isn't true.

Some point being any half-decent middle-school textbook, or any popular science space book for teens. There's usually a footnote or an info box explaining that Earth isn't a perfect sphere.

It's not some arcane nerd knowledge. It's just a detail people don't remember from school because it's irrelevant to their lives.

Re: Space Math Academy

#26
Well people, knowledge become belief. - Position of Moon creating tides, which affect some places very strong, because line of shore constantly moving more then by cup meters, so some operations need to be planned according to tides, this is not belief, this is fact. Position of Sun amplifies tides for up to 50%. BTW, people knowing Astronomy, easy conclude, most extreme Sun tides amplification happen with Sun Eclipse.

I also seen few other wrong classifications.

Sorry, good idea, but such mistakes made it unplayable.

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