A problem with the analysis of type Ia supernovae

[sjastro]

While Michael engages in pure idiocy in claiming the laws of physics are wrong which can proved with the use of non existent Dyson spheres, the rest of us can confirm surface brightness is independent of distance at local scales by using illuminated surfaces and cameras.

The exposure time for both images is the same and the camera's auto brightness and contrast function was disabled.
According to Michael's science fiction the left hand image should be (1/4²)=1/16 the brightness of the right hand image which clearly it isn't.
I could have used a CCD as a photon counter to quantify the test but I can assure you the photon counts would not differ by a factor of 16.
In this case a picture does tell a thousand words.

If Michael wants to continue this exercise of self denial because he doesn't have the backbone of admitting he is wrong, he has ultimately created another 1=0.5 episode.

 

[Michael]

While Michael engages in pure idiocy in claiming the laws of physics are wrong which can proved with the use of non existent Dyson spheres, the rest of us can confirm surface brightness is independent of distance at local scales by using illuminated surfaces and cameras.

Maybe the laws of physics can be proven, but not without control mechanisms and tests that are more sophisticated than anything you just posted. You're clearly confusing "color" for "brightness" which is probably why you failed to use a CCD counter.

If Michael wants to continue this exercise of self denial because he doesn't have the backbone of admitting he is wrong, he has ultimately created another 1=0.5 episode.

The fact that you two continuously and blatantly attribute *false* accusations to me personally, and your constant reliance upon strawmen only undermines your credibility. I had to fix Selfsim's formula and I *used it correctly*.

 

[Michael]

The invalid parts of your St. Obler's paradox nonsense is the fact that scattering occurs in the real universe, redshift is 'predicted' in static universe theories too, there are no single surfaces at cosmological scales, stars aren't all the same brightness, and the distances between objects is *huge*.

The only way any of your oversimplied beliefs work is *on paper*, and never in the real world.

 

[Michael]

The Inverse-Square Law

Here's a "test" for you to try for us sjastro. Go ahead and prove to us that the inverse square laws are invalid.

 

[sjastro]

Maybe the laws of physics can be proven, but not without control mechanisms and tests that are more sophisticated than anything you just posted. You're clearly confusing "color" for "brightness" which is probably why you failed to use a CCD counter.

How ridiculous for you to give me a lecture on control mechanisms when your own procedure to prove otherwise is fictitious and exists in the realm of science fiction.
And stop making stupid comments about confusing colour and brightness.
CCD software programs convert colour images from other cameras into greyscale so the background brightness can be calculated.
In the case of the above image the program Pixinsight calculates the white background of the 16 bit images which has 65,536 different levels ranging from 0=black to 65536=white saturated.
In the 20 metre image the white background averages around 52000 counts and the 5 metre image around 53000 counts given averaging errors.
The ratio is 52000/53000=0.98 which is nowhere near 1/16= 0.06 if surface brightness follows the inverse square law.

 

[sjastro]

The Inverse-Square Law

Here's a "test" for you to try for us sjastro. Go ahead and prove to us that the inverse square laws are invalid.

Once again your lack of comprehension skills are as plain as day.
I suggest you read the article carefully and note the light passes through a SMALL HOLE which is much smaller than the bulb and the distance between the hole and bulb is fixed. Light passing through the hole behaves as a point source.
If surface brightness does follow the inverse square law no hole is required for the test.
Do you think the inverse square law is preserved if the screen was directly exposed to the bulb or the hole is so large that all the light can reach the screen?
In fact the article explicitly tells you the inverse square law is not preserved.

We're now ready for the last step, which is to take away the wall between the light-bulb and the screen! When we do this, the brightness of the light falling on the screen does not change.

Dream on.

 

[Michael]

Once again your lack of comprehension skills are as plain as day.
I suggest you read the article carefully and note the light passes through a SMALL HOLE which is much smaller than the bulb and the distance between the hole and bulb is fixed. Light passing through the hole behaves as a point source.
If surface brightness does follow the inverse square law no hole is required for the test.
Do you think the inverse square law is preserved if the screen was directly exposed to the bulb or the hole is so large that all the light can reach the screen?
In fact the article explicitly tells you the inverse square law is not preserved.

Dream on.

It's deliciously ironic that you accuse *me* of having a "lack of comprehension skills", while you completely and utterly *botched* the whole meaning of that paragraph, and the point of that whole experiment. Here is that particular paragraph *in full*:

We're now ready for the last step, which is to take away the wall between the light-bulb and the screen! When we do this, the brightness of the light falling on the screen does not change. The wall with its central hole helped us define the amount of light falling on the screen, and the bright outline of the hole helped us to see how that fixed amount of light spreads over a greater area as the screen is moved further from the bulb. But the light passing through the hole on its way to the screen `had no idea' that the wall was there, so it produces the same brightness on the screen no matter what. When we take away the wall, more of the screen is illuminated, but the brightness remains the same. The brightness depends on only two things: the luminosity of the light-bulb, and the distance from the bulb to the screen.

Emphasis mine. Apparently you botched the whole meaning of that paragraph and the purpose and the meaning of the whole experiment for that matter.

Removing the wall had absolutely *no effect* whatsoever on the brightness of the screen and therefore brightness depends on only two variables, the luminosity of the source, and the distance. Period! The wall was ultimately *irrelevant to the brightness*, it was simply meant to teach you that photons 'spread out' over distance, and therefore brightness decreases with distance. How could you even miss that? If the brightness had to do with the hole or the wall, the brightness would have *increased/changed* by removing the wall, and there would be a *third* variable that was also important to brightness! The only thing that changed by removing the wall was the amount of the screen that was illuminated, not the *brightness*!

Do you think the inverse square law is preserved if the screen was directly exposed to the bulb or the hole is so large that all the light can reach the screen?

Yes, of course:

But the light passing through the hole on its way to the screen `had no idea' that the wall was there, so it produces the same brightness on the screen no matter what. When we take away the wall, more of the screen is illuminated, but the brightness remains the same.

Wow! Irony overload. You just hoisted yourself with your own petard. One of us does indeed have a serious comprehension problem sjastro, but it isn't me.

I'd comment on the absurdity of your non-scientific (and unmeasured) pretty pictures, but why bother? If you can't understand something as *simple* as this idea of the inverse square law, I don't know how I could possibly help you.

No wonder we're stuck in the dark ages of astronomy.

 

[Astrophile]

It's deliciously ironic that you accuse *me* of having a "lack of comprehension skills", while you completely and utterly *botched* the whole meaning of that paragraph, and the point of that whole experiment. Here is that particular paragraph *in full*:



Emphasis mine. Apparently you botched the whole meaning of that paragraph and the purpose and the meaning of the whole experiment for that matter.

Removing the wall had absolutely *no effect* whatsoever on the brightness of the screen and therefore brightness depends on only two variables, the luminosity of the source, and the distance. Period! The wall was ultimately *irrelevant to the brightness*, it was simply meant to teach you that photons 'spread out' over distance, and therefore brightness decreases with distance. How could you even miss that? If the brightness had to do with the hole or the wall, the brightness would have *increased/changed* by removing the wall, and there would be a *third* variable that was also important to brightness! The only thing that changed by removing the wall was the amount of the screen that was illuminated, not the *brightness*!



Yes, of course:



Wow! Irony overload. You just hoisted yourself with your own petard. One of us does indeed have a serious comprehension problem sjastro, but it isn't me.

I'd comment on the absurdity of your non-scientific (and unmeasured) pretty pictures, but why bother? If you can't understand something as *simple* as this idea of the inverse square law, I don't know how I could possibly help you.

No wonder we're stuck in the dark ages of astronomy.

Consider the thought experiment of measuring the brightness of the Sun from Mars, at its average distance of 1.5237 AU from the Sun. By the inverse square law, the Sun will appear to be only 0.431 times as bright as it appears from the Earth. Also, the angular diameter of the Sun as seen from Mars will be 0.656 times its diameter as seen from the Earth, and its area (solid angle) will be 0.656² = 0.431 times its area as seen from the Earth. Since the ratios of the brightness and the area (solid angle) are the same, it is obvious that the surface brightness of the Sun as seen from Mars and the Earth must be constant, i.e. not dependent on its distance. If the Sun's surface brightness was less as seen from Mars, the reduction in surface brightness would be added to the reduction in total luminosity resulting from the reduction in solid angle, and the Sun's total brightness as seen from Mars would be <0.431 times its brightness as seen from the Earth.

One can do the same calculation for an observer on Proxima Centauri, at a distance of 267,000 AU from the Sun. By the inverse square law, the Sun will appear to be only 14 trillionths as bright as it appears from the Earth. Similarly, the angular diameter of the Sun as seen from Proxima will be 3.7 millionths of its diameter as seen from the Earth, and its solid angle will be 14 trillionths of the solid angle seen from the Earth. Again, this leads to the conclusion that the surface brightness of the Sun does not change with distance.

 

[SelfSim]

Fascinating .. we've just come full circle on this again because of Michael's denials about Olber's paradox and because of his lack of comprehension of the math and the models and the reasoning behind the concept of surface brightness. And we're up to what .. 13 pages now?
There's so much self-induced egg-on-face that Michael's 'argument' has now turned into some kind of liquified scrambled concoction .. what we need now is some heat and some toast!

Hmm ... I predict Michael will now provide that all on his own! ...

PS: Footnote: this is precisely why the Cosmoquest forum ended up with their arguably overly strict moderation rules!

 

[Michael]

Fascinating .. we've just come full circle on this again because of Michael's denials about Olber's paradox

That's because Olber's paradox is a myth perpetuated by people who clearly have no idea what they're talking about as your previous post just demonstrated. You botched that page entirely.

and because of his lack of comprehension of the math

Pure unadulterated projection on your part. You're the one that showed a complete lack of comprehension of the material on that page in your last post, not me. There was plenty of math on the page I cited too to help you out, so you not only didn't comprehend the text, you didn't comprehend the included math either. Double fail.

and the models and the reasoning behind the concept of surface brightness.

The term "surface brightness" is being abused by you. It amounts to nothing more than luminosity per surface area of the source, but nobody ever questioned the fact that the luminosity stays reasonably consistent at the source. We're arguing about brightness at the *receiving end*. You abused that whole concept by trying to apply it where it's utterly inapplicable because you're applying it to objects at different distances and ignoring the massive amounts of empty space between them, not to mention the implications of ordinary (and lab demonstrated) scattering in dusty plasma.

And we're up to what .. 13 pages now?

Ya and apparently you still don't understand the inverse square law, and you're incapable of admitting even your blatantly *obvious* mistakes.

There's so much self-induced egg-on-face that Michael's 'argument' has now turned into some kind of liquified scrambled concoction .. what we need now is some heat and some toast!

Pure projection again. What a howler of an error you made in that last post. Even I was stunned at how silly your last post was.

PS: Footnote: this is precisely why the Cosmoquest forum ended up with their arguably overly strict moderation rules!

Ya, just like you, they don't admit their errors either, and they don't allow for alternative beliefs to be held or discussed there without reacting and behaving badly. The Spanish Inquisition routine at CQ is driven by fear, ignorance and just plain intolerance of free thought and free speech. John Hunter nailed it so of course he had to be publicly flogged as well.

 

[Michael]

Consider the thought experiment of measuring the brightness of the Sun from Mars, at its average distance of 1.5237 AU from the Sun. By the inverse square law, the Sun will appear to be only 0.431 times as bright as it appears from the Earth.

Which clearly demonstrates the inverse square law has a direct effect on the brightness of the object as perceived by the *observer*.

Also, the angular diameter of the Sun as seen from Mars will be 0.656 times its diameter as seen from the Earth, and its area (solid angle) will be 0.656² = 0.431 times its area as seen from the Earth. Since the ratios of the brightness and the area (solid angle) are the same, it is obvious that the surface brightness of the Sun as seen from Mars and the Earth must be constant, i.e. not dependent on its distance. If the Sun's surface brightness was less as seen from Mars, the reduction in surface brightness would be added to the reduction in total luminosity resulting from the reduction in solid angle, and the Sun's total brightness as seen from Mars would be <0.431 times its brightness as seen from the Earth.

In the way that you're using the term, "surface brightness" amounts to nothing more than the average luminosity per surface area of the object, which was never in doubt. That term has nothing to do with the brightness of the object from the perspective of the observer. It's essentially the luminosity of the object itself but even those various objects are not all the same or equally luminous.

One can do the same calculation for an observer on Proxima Centauri, at a distance of 267,000 AU from the Sun. By the inverse square law, the Sun will appear to be only 14 trillionths as bright as it appears from the Earth. Similarly, the angular diameter of the Sun as seen from Proxima will be 3.7 millionths of its diameter as seen from the Earth, and its solid angle will be 14 trillionths of the solid angle seen from the Earth. Again, this leads to the conclusion that the surface brightness of the Sun does not change with distance.

But again, the term "surface brightness" only applies to the luminosity of the object at the source, not the brightness as it's "observed" at the receiving end.

Since there isn't just *one* object in space, and there are massive amounts of space between various objects of different luminosity, it's irrational to try to apply that concept to "layers" of spacetime.

Even the distances to the different objects will dictate the brightness of the various objects as perceived by the observer. That's why we need to point Hubble at those darker regions for *days* to ever see enough photons to observe something that looks like a "galaxy". Their observed brightness is *far* to low to be picked up or recognized by the human brain or the human eye so they would necessarily appear "dark" to the human eye, demonstrating that Olber's paradox is a myth.

 

[sjastro]

It's deliciously ironic that you accuse *me* of having a "lack of comprehension skills", while you completely and utterly *botched* the whole meaning of that paragraph, and the point of that whole experiment. Here is that particular paragraph *in full*:



Emphasis mine. Apparently you botched the whole meaning of that paragraph and the purpose and the meaning of the whole experiment for that matter.

Removing the wall had absolutely *no effect* whatsoever on the brightness of the screen and therefore brightness depends on only two variables, the luminosity of the source, and the distance. Period! The wall was ultimately *irrelevant to the brightness*, it was simply meant to teach you that photons 'spread out' over distance, and therefore brightness decreases with distance. How could you even miss that? If the brightness had to do with the hole or the wall, the brightness would have *increased/changed* by removing the wall, and there would be a *third* variable that was also important to brightness! The only thing that changed by removing the wall was the amount of the screen that was illuminated, not the *brightness*!



Yes, of course:



Wow! Irony overload. You just hoisted yourself with your own petard. One of us does indeed have a serious comprehension problem sjastro, but it isn't me.

I'd comment on the absurdity of your non-scientific (and unmeasured) pretty pictures, but why bother? If you can't understand something as *simple* as this idea of the inverse square law, I don't know how I could possibly help you.

No wonder we're stuck in the dark ages of astronomy.

All you have demonstrated is providing a specific example of why the subject matter is beyond your level of comprehension.
You obviously don’t the understand the meaning of the statement,
“When we take away the wall, more of the screen is illuminated, but the brightness remains the same.”
What exactly do you think the underlined term means?
The answer is the brightness remains the same at any distance hence the inverse square law isn’t applicable.
If it meant anything else as you seem to believe then you are faced with the ridiculous conundrum of explaining how illumination does not increase the brightness level on the screen as attested to your nonsensical spin doctoring that illumination and brightness are different.

If the wall is removed and the screen moved away from the light bulb, the flux will decrease according to the inverse square law and spread out, but the surface area of the bulb over which the light is emitted is also decreasing relative to distance by the same inverse square law.
Astrophile has described the same concept in his post.
Hence the surface brightness which is flux/surface area “remains the same” as described in the link and the inverse square law doesn’t apply for the millionth time.

If you have a wall and a hole much smaller than the lamp the inverse square law does apply as the brightness changes accordingly with distance but there is no dimensional change in the surface area of the lamp as it is obscured by the wall as explained in the link.

What is so ridiculous about your posts is that all you have to do is to find a single reference from a reputable source that explicitly states “Surface Brightness follows the inverse square law”.
You can’t even do that along with denying the physical evidence presented, the references that state otherwise, and most idiotic of all the use of science fiction ala Dyson spheres to justify changing the laws of physics.

 

[sjastro]

Which clearly demonstrates the inverse square law has a direct effect on the brightness of the object as perceived by the *observer*.

In the way that you're using the term, "surface brightness" amounts to nothing more than the average luminosity per surface area of the object, which was never in doubt. That term has nothing to do with the brightness of the object from the perspective of the observer. It's essentially the luminosity of the object itself but even those various objects are not all the same or equally luminous.

But again, the term "surface brightness" only applies to the luminosity of the object at the source, not the brightness as it's "observed" at the receiving end.

What an utterly stupid ignorant comment.
Surface brightness has everything to do with the observer's perspective.

The surface brightness SB=m+2.5log₁₀(A)

m is the integrated brightness measured by the observer.
A is the visual area of the object in the sky measured by the observer.

 

[SelfSim]

... The term "surface brightness" is being abused by you. It amounts to nothing more than luminosity per surface area of the source, but nobody ever questioned the fact that the luminosity stays reasonably consistent at the source. We're arguing about brightness at the *receiving end*. You abused that whole concept by trying to apply it where it's utterly inapplicable because you're applying it to objects at different distances and ignoring the massive amounts of empty space between them, not to mention the implications of ordinary (and lab demonstrated) scattering in dusty plasma.

(My underlines). Hilarious! Thanks for providing your own 'heat'!

Ya and apparently you still don't understand the inverse square law, and you're incapable of admitting even your blatantly *obvious* mistakes.

And so following sjastro's excellent explanatory post (with math included, what's more ), I can now expect you to admit your 'blatantly *obvious* mistakes', eh!?

What a 'classic' this thread this has turned out to be!

... Even I was stunned at how silly your last post was.

Whoaa thar! Hang on a sec ... let me check ... (I must've had ta 'dumb it down' for you to experience that stun, or something!?)

 

[Michael]

All you have demonstrated is providing a specific example of why the subject matter is beyond your level of comprehension.

Irony overload.

You obviously don’t the understand the meaning of the statement,
“When we take away the wall, more of the screen is illuminated, but the brightness remains the same.”

Oh yes I do. It means you're dead wrong.

What exactly do you think the underlined term means?

It means that the brightness level on the screen (at a reduced inverse square law level) remains exactly the same, wall or no wall. Removing the screen doesn't increase the brightness on the screen as would be required for you to actually ignore the inverse square law, it simply increases the surface area of the screen that is lit at a *reduced* level of brightness.

The answer is the brightness remains the same at any distance hence the inverse square law isn’t applicable.

LOL! And to think you have the nerve to lecture me about comprehension problems. What a riot.

If it meant anything else as you seem to believe then you are faced with the ridiculous conundrum of explaining how illumination does not increase the brightness level on the screen as attested to your nonsensical spin doctoring that illumination and brightness are different.

What?

But the light passing through the hole on its way to the screen `had no idea' that the wall was there, so it produces the same brightness on the screen no matter what. When we take away the wall, more of the screen is illuminated, but the brightness remains the same.

Removing the wall does *not* increase the brightness, it increased the area of the screen that was lit at a *reduced* brightness. Holy cow. You really do have serious comprehension problems. Show me the specific math formula on that page that supports your claim sjastro.

If the wall is removed and the screen moved away from the light bulb, the flux will decrease according to the inverse square law
and spread out,

Meaning that the further away that the screen is from from the source, the *dimmer* the light is that reaches the screen, and the smaller the number of photons that reach the observer on Earth! Wow!

but the surface area of the bulb over which the light is emitted is also decreasing relative to distance by the same inverse square law.

No it's not. The *actual* surface of the bulb never changes, only the *apparent* size from the perspective of the observer! The bulb itself doesn't get bigger or smaller! Nobody ever made such a claim to begin with.

Astrophile has described the same concept in his post.

True, but unlike you he didn't ignore the inverse square law or botch the hell out of the description on the page in question. I therefore trust him more than I trust you.

Hence the surface brightness which is flux/surface area “remains the same”

The bulb never changes it's flux to begin with, so *of course* that's true. The bulb doesn't get bigger or smaller, only the *apparent* size from the perspective of the observer. That reduced "flux" as you call it however is *changing with the distance* meaning that less photons reach the observers eyes and they follow the inverse square law.

as described in the link and the inverse square law doesn’t apply for the millionth time.

Wow. You totally botched the meaning of that whole page. You therefore cannot cite the specific math formula on that page that supports any of your claims. Show us that formula sjastro on that page that supports your claims.

If you have a wall and a hole much smaller than the lamp

The hole is only there to illustrate the mathematical aspects of the inverse square law in action. Removing the wall entirely doesn't increase or decrease the brightness on the screen, just the surface area of the screen that is illuminated at a *reduced* (inverse square law) level of brightness. It would be like increasing the area *around* the Earth (away from the observer) that still receives light at a *reduced* level of brightness! How can you muck this up so badly?

the inverse square law does apply as the brightness changes accordingly with distance

Bingo! Therefore two identical stars at different distances will *absolutely* have different levels of brightness, blowing your Olber's paradox claim completely out of the water.

but there is no dimensional change in the surface area of the lamp

The size of lamp is always fixed just like the size of the star is always fixed. Only the *apparent* size changes, just as the brightness changes, not the actual bulb or the actual flux from the bulb itself. The luminosity of the source remains constant, as does the size, but the brightness at the screen (observer) changes with distance, just like the "observed" size changes with distance.

as it is obscured by the wall as explained in the link.

You really didn't grasp any of that explanation correctly, not a single part of it.

What is so ridiculous about your posts is that all you have to do is to find a single reference from a reputable source that explicitly states “Surface Brightness follows the inverse square law”.

Why would I bother trying to do that when I never claimed that the source changed in any way to begin with? That doesn't mean that the same amount of light that reaches the Earth never changes regardless of distance.

You can’t even do that along with denying the physical evidence presented,

You didn't present any real physical evidence to start with, at least nothing that involved measured photon counts related to distance. The photon counts reaching the screen change with distance. With enough distance, the photon counts fall below the threshold of human eyesight, hence the perception of relative "darkness" to a human eye.

the references that state otherwise, and most idiotic of all the use of science fiction ala Dyson spheres to justify changing the laws of physics.

Oh for crying out loud! You've got four science fictional elements all stuffed into one pathetic LCMD model and you're complaining about me introducing a simple "thought experiment" into the discussion. Give it a rest already.

 

[Michael]

What an utterly stupid ignorant comment.

You're not one to talk after that howler of an error you made in last nights post. That was hilarious. Talk about ignorant comments.

 

[Michael]

How Many Stars in the Sky? 9,096—Is That All? | Sky & Telescope

Your whole Olber's paradox nonsense is blown out of the water by a simple visual count of stars in the night sky. While the stars in our own galaxy number into the hundreds of billions, less than 10,000 of them are "bright" enough to be observed by the human eye on Earth.

If your claims about surface brightness always being the same were the only important or relevant issue related to Olber's (non existent) paradox, then we should certainly see every single point source in our own galaxy at exactly the same brightness and every single one of them should be visible to the naked eye on Earth.

In *reality* however, once the inverse square law reduces the amount of light to the point that the magnitude of the star rises above about 6.5, there aren't enough photons reaching Earth to be observable with the naked eye. That issue *alone* blows away your Olber's paradox claim, and it demonstrates that Thomas Digges was right all along. He "got it right" hundreds of years ago, even if you don't "get it" right today.

Your arguments are so lame, and so oversimplified and so childish as to be utterly ridiculous and completely preposterous. The fact that we can't even pick out every star in our own galaxy *destroys* your claim about there being some sort of important "paradox" caused by "surface brightness". There is no paradox caused by surface brightness, just massive confusion on your part as evidenced by your absolute *howler* of an error that you made on that cited page last night.

Hundreds of years ago, Thomas Digges figured out the real reason that we can only see a tiny faction of stars in our own galaxy, and why we cannot possibly hope to see every star in every galaxy even in a static universe. In contrast to Digges, You couldn't be more wrong if you tried.

So called "surface brightness" is utterly and totally irrelevant. The only relevant factors are source luminosity, distance and the limitations of human eyesight. Period. The rest of your claims are oversimplified nonsense and just plain irrational. Even if no redshift and no scattering took place in a static universe, you'd still be wrong. There's simply no possible way that every star in our own galaxy emits enough light to be picked up by the human eye. Period. You're whistling Dixie.

 

[sjastro]

Irony overload.


Oh yes I do. It means you're dead wrong.



It means that the brightness level on the screen (at a reduced inverse square law level) remains exactly the same, wall or no wall. Removing the screen doesn't increase the brightness on the screen as would be required for you to actually ignore the inverse square law, it simply increases the surface area of the screen that is lit at a *reduced* level of brightness.



LOL! And to think you have the nerve to lecture me about comprehension problems. What a riot.



What?



Removing the wall does *not* increase the brightness, it increased the area of the screen that was lit at a *reduced* brightness. Holy cow. You really do have serious comprehension problems. Show me the specific math formula on that page that supports your claim sjastro.



Meaning that the further away that the screen is from from the source, the *dimmer* the light is that reaches the screen, and the smaller the number of photons that reach the observer on Earth! Wow!



No it's not. The *actual* surface of the bulb never changes, only the *apparent* size from the perspective of the observer! The bulb itself doesn't get bigger or smaller! Nobody ever made such a claim to begin with.



True, but unlike you he didn't ignore the inverse square law or botch the hell out of the description on the page in question. I therefore trust him more than I trust you.



The bulb never changes it's flux to begin with, so *of course* that's true. The bulb doesn't get bigger or smaller, only the *apparent* size from the perspective of the observer. That reduced "flux" as you call it however is *changing with the distance* meaning that less photons reach the observers eyes and they follow the inverse square law.



Wow. You totally botched the meaning of that whole page. You therefore cannot cite the specific math formula on that page that supports any of your claims. Show us that formula sjastro on that page that supports your claims.



The hole is only there to illustrate the mathematical aspects of the inverse square law in action. Removing the wall entirely doesn't increase or decrease the brightness on the screen, just the surface area of the screen that is illuminated at a *reduced* (inverse square law) level of brightness. It would be like increasing the area *around* the Earth (away from the observer) that still receives light at a *reduced* level of brightness! How can you muck this up so badly?



Bingo! Therefore two identical stars at different distances will *absolutely* have different levels of brightness, blowing your Olber's paradox claim completely out of the water.



The size of lamp is always fixed just like the size of the star is always fixed. Only the *apparent* size changes, just as the brightness changes, not the actual bulb or the actual flux from the bulb itself. The luminosity of the source remains constant, as does the size, but the brightness at the screen (observer) changes with distance, just like the "observed" size changes with distance.



You really didn't grasp any of that explanation correctly, not a single part of it.



Why would I bother trying to do that when I never claimed that the source changed in any way to begin with? That doesn't mean that the same amount of light that reaches the Earth never changes regardless of distance.



You didn't present any real physical evidence to start with, at least nothing that involved measured photon counts related to distance. The photon counts reaching the screen change with distance. With enough distance, the photon counts fall below the threshold of human eyesight, hence the perception of relative "darkness" to a human eye.



Oh for crying out loud! You've got four science fictional elements all stuffed into one pathetic LCMD model and you're complaining about me introducing a simple "thought experiment" into the discussion. Give it a rest already.

What a hopelessly confusing Gish Gallop type post.
It is so comprehensively wrong as you don’t even understand what surface brightness is.

Let me remind you this is what you stated……..

But again, the term "surface brightness" only applies to the luminosity of the object at the source, not the brightness as it's "observed" at the receiving end.

….. and to then go on to use this incorrect definition to build an argument by claiming surface brightness meets the inverse square law, and leading to being totally confused about illumination and brightness amongst other things.
It’s obvious even to blind Freddie who botched things up.

Since you cannot grasp this most basic concept this post has to be taken down a few notches to a level compatible with your understanding so you can gain some insight into how comprehensively wrong you are.
To gauge the magnitude of your howler let’s use a variation of the "Google is Your Friend" principle.
Compare the number of Google hits for a search on “surface brightness depends on the inverse square law” or the like, to that of “surface brightness is independent of distance”.

I rest my case.

 

[sjastro]

You're not one to talk after that howler of an error you made in last nights post. That was hilarious. Talk about ignorant comments.

How ironic it is was your nonsensical definition of surface brightness that turned out to being the howler.
For someone who doesn’t even understand what surface brightness is, you are in no position of making any judgements.

 

[sjastro]

How Many Stars in the Sky? 9,096—Is That All? | Sky & Telescope

Your whole Olber's paradox nonsense is blown out of the water by a simple visual count of stars in the night sky. While the stars in our own galaxy number into the hundreds of billions, less than 10,000 of them are "bright" enough to be observed by the human eye on Earth.

If your claims about surface brightness always being the same were the only important or relevant issue related to Olber's (non existent) paradox, then we should certainly see every single point source in our own galaxy at exactly the same brightness and every single one of them should be visible to the naked eye on Earth.

In *reality* however, once the inverse square law reduces the amount of light to the point that the magnitude of the star rises above about 6.5, there aren't enough photons reaching Earth to be observable with the naked eye. That issue *alone* blows away your Olber's paradox claim, and it demonstrates that Thomas Digges was right all along. He "got it right" hundreds of years ago, even if you don't "get it" right today.

Your arguments are so lame, and so oversimplified and so childish as to be utterly ridiculous and completely preposterous. The fact that we can't even pick out every star in our own galaxy *destroys* your claim about there being some sort of important "paradox" caused by "surface brightness". There is no paradox caused by surface brightness, just massive confusion on your part as evidenced by your absolute *howler* of an error that you made on that cited page last night.

Hundreds of years ago, Thomas Digges figured out the real reason that we can only see a tiny faction of stars in our own galaxy, and why we cannot possibly hope to see every star in every galaxy even in a static universe. In contrast to Digges, You couldn't be more wrong if you tried.

So called "surface brightness" is utterly and totally irrelevant. The only relevant factors are source luminosity, distance and the limitations of human eyesight. Period. The rest of your claims are oversimplified nonsense and just plain irrational. Even if no redshift and no scattering took place in a static universe, you'd still be wrong. There's simply no possible way that every star in our own galaxy emits enough light to be picked up by the human eye. Period. You're whistling Dixie.

You can’t take a trick.
Here is a reminder again of your definition of surface brightness.

But again, the term "surface brightness" only applies to the luminosity of the object at the source, not the brightness as it's "observed" at the receiving end.

Your inability to comprehend this simple concept only adds weight to what has been stated by a number of individuals in this thread; the nature of the paradox is beyond your capacity for comprehension.