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How Raganwald Lost His Crown

braythwayt.com

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Re: How Raganwald Lost His Crown

#41

Post by uxp »

braythwayt wrote: post #23
bloat wrote: post #22

Earlier quoted context omitted.

I was going to jump in and say that the pound is also a unit of mass. But it turns out its both. https://en.wikipedia.org/wiki/Pound_(force) https://en.wikipedia.org/wiki/Pound_(mass)

And then there's the foot-pound, a unit of torque much prized by the owners of muscle cars until eclectric vehicles went from obscure to early-adopter status.

Or just general torque in the United States. Electric vehicles still have tires that are joined to wheels which are fastened to an axle by the tightening of a nut on a threaded stud. For safety, we generally state that the nut should have X foot-pounds of torque applied to ensure it doesn't fall off. Unless Tesla et al. have suddenly decided to use a more universal standard in the states, I'd assume they still publish that value in ft/lbs, since 98% of tools designed to measure these things owned in the U.S.A. have this unit on them.

Re: How Raganwald Lost His Crown

#42

Post by glandium »

bloat wrote: post #22
braythwayt wrote: post #17

Earlier quoted context omitted.

True, but WaxProlix is correct. Ten kilograms is 22 pounds on Earth, but 2.2 trillion pounds on the given Neutron Star.

I was going to jump in and say that the pound is also a unit of mass. But it turns out its both. https://en.wikipedia.org/wiki/Pound_(force) https://en.wikipedia.org/wiki/Pound_(mass)

Well, there's also https://en.wikipedia.org/wiki/Kilogram-force

Re: How Raganwald Lost His Crown

#43

Post by balfirevic »

braythwayt wrote: post #16
WaxProlix wrote: post #14

Earlier quoted context omitted.

> I would have found that while my scale tells me that I am about 86 kilograms on Earth, I would have weighed 8.6 trillion kilograms on this neutron star. Kilograms are a measure of mass, not weight. Pounds would be a more appropriate unit there.

https://github.com/raganwald/braythwayt.com/commit/b79d17066...

Honestly, I don't think it is any more correct to use pounds instead of kilograms as a substitute for force, as they are both units of mass. I didn't mind the use of kilogram in your specific context, for what is worth.

Re: How Raganwald Lost His Crown

#44

Post by braythwayt »

crimsonalucard wrote: post #40

> Hark to the lesson of this story: Everything has an explanation. Great writing. But the lesson is wrong. It has been proven that certain things which are true can never have an explanation: Godels incompleteness theorem. https://www.wikiwand.com/simple/G%C3%B6del%27s_incompletenes...

I do not think Incompleteness speaks to the question of whether things that happen in our Universe have explanations. It speaks to formal mathematical systems that have a property of self-reference.

If we are to debate whether the conclusion of my parable is true, I would tend more towards considering the possibility that many things in our Universe may simply be axiomatic, there is no explanation for them, they just are. Uncertainty may be one of those things.

Another line of investigation would be to consider whether some things do have explanations, but we have missed the opportunity to gather the evidence to understand them, therefore we will never understand them. Likewise, the Universe is finite, it will die, and we may never discover all of the explanations.

If something has an explanation, but there is no way for us to discover it, in what sense does it have an explanation?

Re: How Raganwald Lost His Crown

#46

Post by smoyer »

WaxProlix wrote: post #18
bryanl wrote: post #15

Earlier quoted context omitted.

Most of the people world weigh themselves in kilograms.

They roughly infer their mass (in kilograms) by assuming 9.8m/s/s gravitational acceleration and using a scale to judge how much mass the resulting 'push' would require given that pull. A scale would tell you that you weight slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass. Same is true on a neutron star. It's an easy shorthand for the most part, since we're not 'we…

Because a hike like that will really burn off the pounds ... er, I mean kilograms. (Joke)

Re: How Raganwald Lost His Crown

#48

Post by WaxProlix »

thaumasiotes wrote: post #25
WaxProlix wrote: post #18

Earlier quoted context omitted.

They roughly infer their mass (in kilograms) by assuming 9.8m/s/s gravitational acceleration and using a scale to judge how much mass the resulting 'push' would require given that pull. A scale would tell you that you weight slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass. Same is true on a neutron star. It's an easy shorthand for the most part, since we're not 'we…

> A scale would tell you that you weigh[] slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass. For an illustration of a pedantic distinction, this seems awfully unlikely to be correct. You gain mass by eating and drinking and lose it by urinating, defecating, and breathing; odds are you're not going to have the same mass on the mountaintop.

> pedantic

Think you're maybe projecting? It was meant to be a silly example and taking a super uncharitable interpretation (object x at different times or states with different masses) of my statement just to be able to pick a nit strikes me as more pedantic than responding to a request for corrections with my high school level understanding of basic units.

Re: How Raganwald Lost His Crown

#49

Post by crimsonalucard »

braythwayt wrote: post #44
crimsonalucard wrote: post #40

> Hark to the lesson of this story: Everything has an explanation. Great writing. But the lesson is wrong. It has been proven that certain things which are true can never have an explanation: Godels incompleteness theorem. https://www.wikiwand.com/simple/G%C3%B6del%27s_incompletenes...

I do not think Incompleteness speaks to the question of whether things that happen in our Universe have explanations. It speaks to formal mathematical systems that have a property of self-reference. If we are to debate whether the conclusion of my parable is true, I would tend more towards considering the possibility that many things in our Universe may simply be axiomatic, there is no explanation for them, they just…

The incompleteness theorem does not only apply to mathematical systems. It applies to all formal systems in the realm of logic. If we assume that all of reality can be reduced to a formal logical system then the incompleteness theorems apply. Thus even non-axiomatic concepts may be unexplainable.

However, you bring up a good point. Explanations rely on evidence and evidence must be observed. Additionally, the tools which we employ to observe evidence are imperfect. What does this mean?

It means in the world of logic only some things can't be proven, but in the world of science (aka reality as we know it): Nothing can be proven. Nothing can be fully explained because additional evidence can always be observed in a later point in time that disproves an explanation. As Einstein once said:

"The scientific theorist is not to be envied. For Nature, or more precisely experiment, is an inexorable and not very friendly judge of his work. It never says "Yes" to a theory. In the most favorable cases it says "Maybe," and in the great majority of cases simply "No." If an experiment agrees with a theory it means for the latter "Maybe," and if it does not agree it means "No." Probably every theory will someday experience its "No"—most theories, soon after conception."

or Karl Popper who put the concept simply:

"...no matter how many instances of white swans we may have observed, this does not explain the conclusion that all swans are white."

In short, no amount of evidence or explanation can justify any statement.

Interestingly though, it takes only one observed black swan to disprove a statement. Hence the role of falsifiability in the scientific method.

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