AIBU to question the popular belief that there are more stars in the sky than grains of sand on earth?

[Tryingtryingandtrying]

How can this possibly be true? Tbh I'd question if there were more stars than grains of sand on my local beach? I've read a bit around it and still is impossible for me to comprehend. Any other facts or theories that just don't make sense to you?

There are an enormous number of holes in that explanation. If you want a robust model, you need the maths.

But if there are holes in the explanation, there are holes in the explanation and I am not going to accept it uncritically. I am not going to understand the maths (as you know) so as far as I am concerned, it’s just an explanation with holes in it.

And that is because what you have described is a theory, not complete and factual information. It is the best explanation science thinks it has for something currently unobserved and inexplicable. That’s clear from your post:

“Why would that change somewhere we can't see? "Because you find the conclusion unintuitive" is not such a reason.”

You don’t know it doesn’t change. You are assuming it doesn’t, from everything you have seen before. That’s not unreasonable, as far as it goes, but it isn’t proof.

So your “so space is expanding and it's infinite” is what I think it is: a theory, and one that doesn’t make sense at that.

I said the "space expanding" explanation was "unsatisfying" and that it might in some senses be better to say other things (but all those other things have problems too), and that a rigorous model is mathematical. I never said "space expanding" makes no sense.

And nor did I. I said “expanding AND” infinite makes no sense.

But in any case, I am not even sure (from what has been discussed here) that I agree that the evidence shows space is “expanding” (as in, space itself, which is ‘nothing’, so I am not sure how it can ‘expand’, but maybe that’s for another day). Rather it shows that everything observable (galaxies etc) is moving away from everything else observable, so the space between those objects is increasing, rather than expanding. No?

I think you're the problem actually

burfordbrown

Do you mean me?

@AStudyinPink

burfordbrown

Do you mean me?

Yes!

burfordbrown

What problem do you think I’m causing?

Space may or may not be infinite. Stuff in it are moving further apart though so it is expanding, right?

Yes it is expanding. The expansion leads us to three possible fates of the universe, based on a critical density of the universe: The key parameter is the ratio of the current universe’s density rho to the critical density rho_c.
If rho is greater than rho_c, then the universe is a closed universe
It suggests that the density of the universe is so high that gravity will prevent galaxies from travelling out into space indefinitely
Expansion slows down, stops, then contracts to a single point – the Big Crunch
If rho is smaller than rho_c, then the universe is an open universe
The density of the universe is not enough for gravity to prevent galaxies drifting away from each other forever
This results in the Big Freeze/Chill, which means the universe basically freezes out to boringness; nothing happens, or the Big Rip, which is caused by dark energy ripping everything apart
If rho is equal to rho_c, then the universe is a flat universe
Absent of dark energy, a flat universe expands forever but at a continually decelerating rate, with expansion asymptotically approaching zero.
With dark energy, the expansion rate of the universe initially slows down, due to the effect of gravity, but eventually increases.
The ultimate fate of the universe is the same as an open universe

BobbinThreadbare123

But again, you aren’t describing the universe expanding, but the observable universe, I.e. the stuff in the universe.

Space itself? We don’t know if it is infinite or not.

Stuff in it are moving further apart though so it is expanding, right?

Maybe. I don’t know.

@AStudyinPink Come on then, O Great Cosmologist - sort it all out for us. Those of us who genuinely do have physics/astronomy/astrophysics/cosmology quals are very interested to know.
I think people might be forgetting that the model is incomplete - we don't actually know. We've not been able to tie gravity in with the other forces yet in the Standard Model, so why should we have all of the answers here?

Why are you like this? @AStudyinPink

@burfordbrown I've actually reported them - they've basically filled up a cool discussion thread with waffly crap, presumably to get a rise out of people thanks to boredom/troll tendencies.

Wow.

When the words don’t make sense in English but there is some hidden esoteric meaning that I will understand when I access their higher plane of thought

Not everything can be made sense of in English though. There are plenty of words and phrases that can't effectively be translated from one language to another. To truly understand some words or phrases you need to not only understand the word but also the context, concepts and culture around that word.

Imagine someone who has never seen snow before, has never experienced temperatures cold enough to freeze water and who doesn't speak English asks you what the word snow meant. You'd never be able to explain it unless they learned your language well enough to communicate effectively with you.

Or as another example

Many people consider Matsuo Basho to be a master of Haiku but if you read his work in English it loses some of its magic as the meanings, context and flow of Japanese can't be 100% translated into English. This doesn't mean his work is any less special just because English, French or German speakers can't fully understand it.

So it is with the concepts SpeverendRooner speaks about. Unless you understand the language of maths you'll always lose some of the meaning and thus never be able to fully understand it. If you do want to fully understand it's up to you to learn the maths, just like if you want to fully appreciate Basho's work you'll need to learn Japanese.

It's exactly why English (and all other languages) borrow words from other languages. So in the case of trying to explain the universe, English needs to borrow from mathematics

Answering ops initial question, just the whole thing of making a baby.

Sperm and egg combine, magic. Great. Then they split and split into identical cells and those cells just KNOW which genes to switch off for the cells to differentiate to become your butt or your brain, or a salivary gland or blood cells on your kidney. And by and large, it does it ok.

I have a child with a congenital defect so I see that sometimes it gets buggered up, and I accept that most early miscarriages are due to it not forming right, but by and large, we all have two eyes in the same place, two ears in the same place, two variations on sex organs and genitals (I said broadly speaking). I just find it crazy.

I also have twins (I'm like MN cliché, a SN child and twins) so their first(ISH?) division got over excited and split into two and then still made two perfect (big) babies.

Buccanarab

You might be right. I don’t know. At the moment, the claims made (in English, to a person who understands English) don’t make sense. Saying something can only be understood in mathematical terms is all very well, but that isn’t what is being said; what is being said is that the universe is infinite and space is expanding. In English, where those words have specific meanings, that doesn’t make sense, so I am sceptical about it. I haven’t said it’s nonsense - just that I am sceptical.

My saying so appears to have upset the posters above. I don’t know why.

@AStudyinPink

Buccanarab

You might be right. I don’t know. At the moment, the claims made (in English, to a person who understands English) don’t make sense. Saying something can only be understood in mathematical terms is all very well, but that isn’t what is being said; what is being said is that the universe is infinite and space is expanding. In English, where those words have specific meanings, that doesn’t make sense, so I am sceptical about it. I haven’t said it’s nonsense - just that I am sceptical.

My saying so appears to have upset the posters above. I don’t know why.

Because you can't see passed your own nose and it's getting old

If you do want to fully understand it's up to you to learn the maths, just like if you want to fully appreciate Basho's work you'll need to learn Japanese.

Yes. I was thinking about trying to describe music or art. There may be words which describe some aspects but at some point if people actually want to understand they have to listen or look and learn technicalities.

[quote SpeverendRooner]@AStudyinPink - the best I can do is this. How could you tell if something was expanding? From a distance, where you can see the edges, you could take a sequence of photos and compare the sizes over time. But what if you can't see the edges? Like if something really big like the Earth were expanding (and we had no satellites or distant vantage points). Well, we could stick two stakes in the ground and measure the distance between them with a ruler and see if they were moving apart. We'd need a lot more than two stakes, because we'd want to see that it was a global things, not just something like a landslip dragging one of the stakes somewhere. That method would work whether there were an edge and we couldn't see it, or there were no edge.

The galaxies we see out there are what we use instead of stakes in the ground. And everywhere we look they are moving away from us, the further away the faster. Furthermore, if you look at the pattern of movement in detail, it turns out that it wouldn't matter where you stood - you would always see the same thing, everything far from you moving away, the further the faster. That means that there's no center that everything is moving away from, but rather everything is moving away from everything else. What better word for that than expansion?

So "space is expanding".

I explained the reason for "infinite" earlier. The laws of physics look the same everywhere we can see and the universe looks the same everywhere we can see. So you have to assume that the laws change somewhere in order to get an edge. It's a bit like (before the 1960s) it was only an assumption that the moon had an other side. We'd never seen it until the Apollo missions, so a strict positivist would have regarded the hypothesis that it has an other side as unproven. But every other thing we've ever seen has a reverse side if it has a front side, and a thing that had only one side and just wasn't there from the other side is so alien to everything that we know that it's implausible. So it is with the universe. Everywhere we can see, you would see the same thing, everything travelling away from you. Why would that change somewhere we can't see? "Because you find the conclusion unintuitive" is not such a reason.

So space is expanding and it's infinite.

There are an enormous number of holes in that explanation. If you want a robust model, you need the maths.[/quote]
Great explanation, thanks for trying to translate to simple examples

The claims made do make sense, but you are too arrogant, or stubborn or dumb to see it.

The fact that you can’t grasp it doesn’t make it wrong. Here is the claim, in plain English: “both of these things are true - the Universe is infinite and space is expanding - and to understand how this seemingly unsolvable paradox can be true you need to understand some very complex mathematics.”

Sure, you can not understand it. I don’t understand it. But you don’t need to enter a higher plane of thought to understand it, you just need to learn some more maths.

It is unsufferably arrogant to think that your level of comprehension, knowledge or understanding is the benchmark by which the truth of the universe is judged.

Some really angry people here. Shocking, actually. But I will continue with my reasonable level of scepticism whatever you say, so I think it’s best left at that.

burfordbrown

It’s ‘past’ not ‘passed’.