Anyone keen to photograph some candles, for scientific experiment?

[tris_d]

If somebody can arrange for 8,10,12,or even up to 24 bikini-clad women to show up in one location, I will gladly buy a bunch of candles and will undertake this challenge, and will photograph the chit outta this here candle thing...but otherwise,without the bikinis...it's a non-starter...

Hehe. We sorted it out, the illustration is wrong. Good luck with bikini-clad women.

 

[amolitor]

Olber's paradox is stupid, it turns out. Infinities are more complicated than that.

In an infinite universe with an infinite number of stars, with pretty much whatever other parameters you want, you can arrange to have whatever percentage of the night sky you like be completely blank out to infinity, regardless of whether the stars get brighter, dimmer, or what have you.

In fact, if your universe was a sphere, you could have infinitely many "stars" made up of finite white dots pasted to the inside of your sphere. If I was allowed to make the little white dots arbitrarily small - never zero, but arbitrarily close to zero, I can fit in an infinity of them on the finite surface of the sphere, and cover as little of that sphere's surface as you like.

 

[tris_d]

I'm referring to what I quoted. It's not that hard to figure out.

Sorry. I didn't realize at first you cut my quote to point out what you were referring to, but still your point was unclear.

Olbers' Paradox doesn't state every line of sight ends in a star. It stated that IF the universe was infinite, then that would be true.

Yes, which is why I think I have to use the same premise to prove the original conclusion was wrong, but I don't see infinity matters anyway.

Of course, his observation was made during a time when the universe was assumed to be static, and not expanding as is the current model. Given an infinite universe, every line of sight will end in a star, but we may not be able to see it with the visible spectrum because if a star is far enough away, the Doppler Effect will render it invisible to our eyes.

It's all the same to me, that does not invalidate inverse square law would be what explains the "darkness". Finite and expanding universe would just make it even darker.

That said, since whatever doesn't make sense to you, you immediately and summarily dismiss based on your own prejudices and preconceived notions, I'm done here.

What did I dismiss? I don't think I dismissed anything you said, I'm giving you my response here. And unlike most of the people on the internet I have no problem to admit when I am wrong, because it means that I learned something new. You prove me wrong and I will thank you for it, like I did in the previous discussion.

 

[unpopular]

post a photo or gtfo.

 

[tris_d]

post a photo or gtfo.

Are you talking to me? What photo? What "gtfo" means?

 

[fjrabon]

it seems to me no matter how many of those less bright stars are, they could not appear any more bright than what their individual brightness is. Where is the paradox?

Not to dredge this back up, but this is where you are wrong. When stars get arbitrarily close, our eyes begin resolving them as a single star, and then the two stars dimness is additive, and they seem brighter. There are all sorts of 'dual' stars, that are much brighter than they should be, because they are 2 stars combined. ie if there are two stars, that are very close to one another in our angular vision, and let's say one brightness is 10 units, and the other star is 6 brightness, they will appear to our eyes as one star of brightness 16. This concept is the backbone behind olber's paradox, as originally conceived.

The big killer of olber's paradox is the fact that the universe had a beginning and is expanding. Two key assumptions to the paradox are that the universe has always been around and that it is static.

 

[unpopular]

What photo?

my point exactly.

 

[tris_d]

When stars get arbitrarily close, our eyes begin resolving them as a single star, and then the two stars dimness is additive, and they seem brighter. There are all sorts of 'dual' stars, that are much brighter than they should be, because they are 2 stars combined. ie if there are two stars, that are very close to one another in our angular vision, and let's say one brightness is 10 units, and the other star is 6 brightness, they will appear to our eyes as one star of brightness 16. This concept is the backbone behind olber's paradox, as originally conceived.

That's about where we left it off when we went on about candles argument. I'm pretty sure nothing like that was related to Olbers' paradox, and I've read many papers and internet articles about the paradox. In any case, where did you get that? Is that in knowledge written in Astronomy text books, is it some photography related effect, where do I confirm what you just said? Can you give me some link or tell me what do I google for?

The big killer of olber's paradox is the fact that the universe had a beginning and is expanding. Two key assumptions to the paradox are that the universe has always been around and that it is static.

That does not invalidate inverse square law would be what explains the "darkness". Finite and expanding universe would just make it even darker.

 

[fjrabon]

When stars get arbitrarily close, our eyes begin resolving them as a single star, and then the two stars dimness is additive, and they seem brighter. There are all sorts of 'dual' stars, that are much brighter than they should be, because they are 2 stars combined. ie if there are two stars, that are very close to one another in our angular vision, and let's say one brightness is 10 units, and the other star is 6 brightness, they will appear to our eyes as one star of brightness 16. This concept is the backbone behind olber's paradox, as originally conceived.

That's about where we left it off when we went on about candles argument. I'm pretty sure nothing like that was related to Olbers' paradox, and I've read many papers and internet articles about the paradox. In any case, where did you get that? Is that in knowledge written in Astronomy text books, is it some photography related effect, where do I confirm what you just said? Can you give me some link or tell me what do I google for?

The big killer of olber's paradox is the fact that the universe had a beginning and is expanding. Two key assumptions to the paradox are that the universe has always been around and that it is static.

That does not invalidate inverse square law would be what explains the "darkness". Finite and expanding universe would just make it even darker.

It's the well known idea of if you want to double your light, you add another light. You get twice as much light. When the two points are close enough they look like one, and since there is twice as much light, coming from the same seeming point, the apparent brightness is doubled.

Any photographer who has ever used multiple speedlights to double their light power understands this concept extremely well.

 

[tris_d]

It's the well known idea of if you want to double your light, you add another light. You get twice as much light. When the two points are close enough they look like one, and since there is twice as much light, coming from the same seeming point, the apparent brightness is doubled.

Any photographer who has ever used multiple speedlights to double their light power understands this concept extremely well.

Photographers don't use point light sources. And in why would it even matter whether the stars are close or not? Look, I'm open to what you are saying, but that's far from enough to convince me. I need references and some more practical proof to confirm it would work as you're suggesting it would. And I'll help you to prove me wrong, just tell me what to google for.

 

[fjrabon]

It's the well known idea of if you want to double your light, you add another light. You get twice as much light. When the two points are close enough they look like one, and since there is twice as much light, coming from the same seeming point, the apparent brightness is doubled.

Any photographer who has ever used multiple speedlights to double their light power understands this concept extremely well.

Photographers don't use point light sources. And in why would it even matter whether the stars are close or not? Look, I'm open to what you are saying, but that's far from enough to convince me. I need references and some more practical proof to confirm it would work as you're suggesting it would. And I'll help you to prove me wrong, just tell me what to google for.

Because the whole reason why stars appear to get dimmer is that our eyes can't resolve their size. When two stars are close enough in our visual plane to be unresolvable as two distinct points, then the same thing happens. Just like our eyes couldn't resolve the size of distant sources and thus just makes them appear dimmer instead of smaller, two arbitrarily close points, when our eyes can't resolve them as separate points, the apparent brightness is additive between the two stars individual brightness.

If you can't get this, I am just done. This is a well understood concept, and I am telling you that it is true, in various astronomy texts

here is just one link that talks about double (or more) stars, and why they look brighter. it's estimated that up to 50% of the visible stars in our universe are actually multiple stars combining their brightness to increase their visibility.

Fun with double and variable stars - Astronomy Magazine

 

[Helen B]

I have the impression that you haven't yet really understood the relationship between distance and apparent brightness.

Instead of using our current understanding of the universe to explain Olbers' Paradox, you are using your misunderstanding of simple principles to try to explain it.

 

[tris_d]

Because the whole reason why stars appear to get dimmer is that our eyes can't resolve their size. When two stars are close enough in our visual plane to be unresolvable as two distinct points, then the same thing happens. Just like our eyes couldn't resolve the size of distant sources and thus just makes them appear dimmer instead of smaller, two arbitrarily close points, when our eyes can't resolve them as separate points, the apparent brightness is additive between the two stars individual brightness.

If you can't get this, I am just done. This is a well understood concept, and I am telling you that it is true, in various astronomy texts

here is just one link that talks about double (or more) stars, and why they look brighter. it's estimated that up to 50% of the visible stars in our universe are actually multiple stars combining their brightness to increase their visibility.

Fun with double and variable stars - Astronomy Magazine

I get that, but that does not change anything. Binary stars are brighter than one star would be, but still they appear less bright the further away they are. See those gray dots on the image below, many of them are binary stars and single stars millions of times brighter than Sun, yet when they are far away they appear dim.

Apparent magnitude - Wikipedia, the free encyclopedia
- Note that brightness varies with distance; an extremely bright object may appear quite dim, if it is far away. Brightness varies inversely with the square of the distance.

 

[fjrabon]

Because the whole reason why stars appear to get dimmer is that our eyes can't resolve their size. When two stars are close enough in our visual plane to be unresolvable as two distinct points, then the same thing happens. Just like our eyes couldn't resolve the size of distant sources and thus just makes them appear dimmer instead of smaller, two arbitrarily close points, when our eyes can't resolve them as separate points, the apparent brightness is additive between the two stars individual brightness.

If you can't get this, I am just done. This is a well understood concept, and I am telling you that it is true, in various astronomy texts

here is just one link that talks about double (or more) stars, and why they look brighter. it's estimated that up to 50% of the visible stars in our universe are actually multiple stars combining their brightness to increase their visibility.

Fun with double and variable stars - Astronomy Magazine

I get that, but that does not change anything. Binary stars are brighter than one star would be, but still they appear less bright the further away they are. See those gray dots on the image below, many of them are binary stars and single stars millions of times brighter than Sun, yet when they are far away they appear dim.

Apparent magnitude - Wikipedia, the free encyclopedia
- Note that brightness varies with distance; an extremely bright object may appear quite dim, if it is far away. Brightness varies inversely with the square of the distance.

Yes, we all understand the inverse square law. My point is that the whole theory behind olber's paradox is that as you get infinite space, you get infinite stars, infinitely densely packed in the visual field. And since light is additive, it would appear bright, even if each individual component star was quite dim. In fact most stars we see, couldn't be seen by our eyes, if they weren't binary stars. Because stars can add together in their brightness, it enables many more stars to be easily seen, that would otherwise take very powerful microscopes. Now, if we had infinite space that was static, and no atmospheric dust, and infinite duration of the universe, and no dark matter, then we very much would have Olber's perfectly bright sky. Because even though stars would be very dim as they got far away, there would be infinity of them, perfectly coating the visual field, making it appear as a gigantic curved plane. THink instead of a binary star, an infinitary star. ie a binary star made out of infinity stars. That's what Olber's paradox is about. Now, of course we have an expanding universe, that had a beginning, and has dust in space, and has dark matter in space, and stars burn out and are born, so none of the background assumptions that created Olber's paradox are actually true.

However, the one single thing that you think that explains away Olber's paradox, the inverse square law and how it relates to how we see light, is actually the very thing that actually makes Olber's paradox viable. Your issue with it is literally the only reason it MIGHT have worked, if all the other assumptions hadn't been wrong.

 

[tris_d]

My point is that the whole theory behind olber's paradox is that as you get infinite space, you get infinite stars, infinitely densely packed in the visual field.

If every line of sight ends at some star, that's where that line of sight ENDS, and if every line of sight ends at some point, then there is nothing infinite about it. Yes, it will be densely packed, as it is, some stars bright, some stars less bright, and some very distant stars as bright as black.

And since light is additive, it would appear bright, even if each individual component star was quite dim.

How do you suppose many gray dots would add up to become many white dots?

In fact most stars we see, couldn't be seen by our eyes, if they weren't binary stars. Because stars can add together in their brightness, it enables many more stars to be easily seen, that would otherwise take very powerful microscopes. Now, if we had infinite space that was static, and no atmospheric dust, and infinite duration of the universe, and no dark matter, then we very much would have Olber's perfectly bright sky. Because even though stars would be very dim as they got far away, there would be infinity of them, perfectly coating the visual field, making it appear as a gigantic curved plane.

If some stars are bright and other less bright, how do you arrive to conclusion there would be uniform brightness across the sky?

THink instead of a binary star, an infinitary star. ie a binary star made out of infinity stars. That's what Olber's paradox is about. Now, of course we have an expanding universe, that had a beginning, and has dust in space, and has dark matter in space, and stars burn out and are born, so none of the background assumptions that created Olber's paradox are actually true.

You can not compare them all with binary stars as if they are all that close next to each other. When they are really close they appear as one star, but otherwise two stars that appear next to one another, one of them is more likely to be millions of light years closer to us than the other. Finite and expanding universe does not invalidate inverse square law could be what explains the "darkness" of the night sky, it would just make it even darker.

However, the one single thing that you think that explains away Olber's paradox, the inverse square law and how it relates to how we see light, is actually the very thing that actually makes Olber's paradox viable. Your issue with it is literally the only reason it MIGHT have worked, if all the other assumptions hadn't been wrong.

The inverse square law makes Olbers' paradox viable? Why, how? Might have worked? Can you rephrase what do you mean to say?