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Weird Physics Facts

telegraph.co.uk

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Re: Weird Physics Facts

#21

Post by sp332 »

gizmo wrote: post #18
rpledge wrote: post #12

Earlier quoted context omitted.

The real question is could all the matter that makes up sugar cubes fit inside a sugar cube? Inquiring minds want to know!

Easily. Assume sugar cubes consist 100% of sugar. Then the question becomes, what has more mass: the world's population or the world's supply of sugar. There definitely isn't enough sugar in the world to give everybody his own weight in sugar (including the sugar that naturally forms in plants / fruit), so there's your answer.

There are 7 Kg / person of sugar produced annually, I think the total amount of sugar on the planet is at least as large as the total amount of people.

Re: Weird Physics Facts

#22

Post by gizmo »

sp332 wrote: post #21
gizmo wrote: post #18

Earlier quoted context omitted.

Easily. Assume sugar cubes consist 100% of sugar. Then the question becomes, what has more mass: the world's population or the world's supply of sugar. There definitely isn't enough sugar in the world to give everybody his own weight in sugar (including the sugar that naturally forms in plants / fruit), so there's your answer.

There are 7 Kg / person of sugar produced annually, I think the total amount of sugar on the planet is at least as large as the total amount of people.

I don't see how that follows. The amount of sugar produced is roughly equal to the demand for sugar -- and as sugar is eaten it immediately decomposes and ceases to be sugar.

So there is a fixed surplus of sugar in the world, and that's the only relevant amount. Production and consumption cancel each other out.

Assuming the average person weighs 50kg, there has to be a 5 year surplus in order for the surplus per person to be heavier than the person. I consider it highly unlikely we stockpile a 5 year supply of sugar (200+ billion kg) -- especially since there is no incentive to do so.

Re: Weird Physics Facts

#23

Post by WilliamLP »

This is a stunningly bad article. The author is a faker.

> If the Sun were made of bananas, it would be just as hot

Maybe, maybe not. The heat from the sun comes from fusion of hydrogen into helium. If it were mostly helium, it would be much much hotter. (That's a red giant.) With the carbon, oxygen, and whatever else in bananas, who knows.

> Events in the future can affect what happened in the past

Affect is an absolutely terrible choice of words for this. Events at a distance can be set up to be correlated in strange, "spooky" ways, but this in no way can be used to communicate back in time or faster than light. So "affect" is a tragically ill-chosen verb.

> Things can travel faster than light; and light doesn’t always travel very fast

I think a real physicist would weep at this faker's explanation here.

> There are an infinite number of mes writing this, and an infinite number of yous reading it

> According to the current standard model of cosmology,

There are wild theories (some may even be testable someday, some may not), but this is no "standard" model of cosmology.

Re: Weird Physics Facts

#24

Post by pvg »

gizmo wrote: post #14
ramchip wrote: post #9

[The sun] is hot because its enormous weight – about a billion billion billion tons – creates vast gravity, putting its core under colossal pressure. But, isn't it hot because the confinement permits nuclear fusion? Just sitting there and having gravity is totally related to being hot or not; it's not like you can create energy out of nothing. If the sun were made of bananas, wouldn't it just become a very compact, c…

Banana's, if I'm not mistaken consist mostly of carbon and hydrogen. Since hydrogen is the easiest to fuse you'd get a hydrogen fusion reaction in the core of the bananasun. Over time heavier elements are created as the product of fusion. The only thing that remains of the original bananas is the color yellow, which explains the color of the sun.

By mass, mostly oxygen and carbon (googling around, ~70+% water, ~20+% carbohydrates). Compared to the sun (~70+% hydrogen, almost all of the rest is helium), the amount of hydrogen is tiny . The density of the sun is substantially higher than its banana-replacement as well - 1.4 g/cm^3 vs a bit over 1 g/cm^3. It seems like you end up with a star that would fuse the limited amounts of hydrogen and resulting helium but is too small to get any further. The 'would be just as hot' thing seems like a bit of newspapery oversimplification - at solar masses (and below) bananium doesn't appear to be very good stellar fuel.

Re: Weird Physics Facts

#25

Post by jriddycuz »

hristov wrote: post #7
chrischen wrote: post #2

One more weird fact: scientists conduct experiment that show that reality doesn't exist! http://news.ycombinator.com/item?id=937329 Basically they found out that properties do not exist until after they are observed.

It seems that, just like Haskell, the universe operates according to lazy evaluation.

I guess this makes human observation monadic.

Re: Weird Physics Facts

#26

Post by lt »

roundsquare wrote: post #20
lt wrote: post #8

Earlier quoted context omitted.

Physics has been a recent interest for me, for all its weirdness. I was thinking about this issue in particular yesterday. Made me think of Thirteenth Floor - the simulation doesn't need to happen until someone observes it Maybe we were written in a functional language with Lazy Evaluation. Maybe the issue isn't if it the tree makes a sound - does it fall at all if there's no one around?

Is it possible that when you get to the forest the tree has retroactively fallen down?

If realism is proven to be invalid, then that could be true.
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