# Why is the BBT believed to be an accelerating expansion?

• October 4th, 2014, 12:07 AM
kojax
Why is the BBT believed to be an accelerating expansion?
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us.

However, I see a problem with this. Expansion would not only make light from faraway objects shift toward the red end of the spectrum. It would also make it dimmer.

That is to say, if space is expanding in all directions, not just one direction. If there is a spherical light wave traveling away from our standard candle, and space is also expanding as the light wave expands, then it should carry the crest of that light wave with it, so that after traveling for a time, the surface area of that sphere would be greater than . The fact the space enclosed by the sphere has been expanding would increase the size of the sphere.

If there were a fixed number of photons in that wave crest when it began, then as the surface area of the sphere grows, the photon density would be less and less. Absent expansion, the only way the surface area grows is by the light traveling outward at C. With expansion, it is able to grow both ways. It also grows as the space expands.

Photon density and brightness are exactly the same thing. Therefore,we must be seeing standard candles in a way that makes them appear now to be further away than they were when they originally emitted the light we see. (And the degree to which they appear further away should be exactly equal to the distance expansion has carried them away from us.)

Therefore, there is no need for an accelerated expansion. If we're seeing our candles at the distance where they have arrived at now, then we don't need to account for how far they must have moved before the light could reach us. That has already been accounted for by the dimness of the light.
• October 4th, 2014, 08:43 AM
Zwirko
From what you describe it appears as if you have your standard candles fading away with distance at a uniform rate. As you look out at ever greater distances the dimming of standard candles is not observed to be linear. It's changing.
• October 4th, 2014, 04:32 PM
tk421
Quote:

Originally Posted by kojax
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us...

You have oversimplified how it works to the point of caricature. Astrophysicicsts are not as foolish and naive as you seem to think. I recommend starting by reading the wiki entry on the cosmic distance ladder: Cosmic distance ladder - Wikipedia, the free encyclopedia

The raw data are used together with cosmological models to deduce the rate of expansion. The type 1a supernovae data led inevitably to the conclusion that the rate of expansion is increasing. This work won a Nobel for Perlmutter, Schmidt and Riess in 2011.
• October 5th, 2014, 12:49 PM
kojax
There is a trend I'm seeing lately of people suggesting that if you question a physicist's conclusions, you're somehow also questioning whether they are "smart".

That's a bad trend to have in any scientific community because, first of all, smart people are wrong all the time, but second of all it make ad-hominem into the dominant rule of discourse.

"A smart person said it, therefore it must be true". Such rubbish.

Quote:

Originally Posted by tk421
Quote:

Originally Posted by kojax
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us...

You have oversimplified how it works to the point of caricature. Astrophysicicsts are not as foolish and naive as you seem to think. I recommend starting by reading the wiki entry on the cosmic distance ladder: Cosmic distance ladder - Wikipedia, the free encyclopedia

I don't mean it that way. I'm trying to present the problem in a way so I can get an answer that addresses it.

I have to name the paradox, before anyone can tell me how it resolves. And the more precisely I name it, the better the answer I hope to get.

I'm just thinking that expansion should effect the dimness of a standard candle in the same way as traversed distance affects it, and wondering what observations have been made that suggest there is more to the picture.

The linked wiki article had this to say about standard candles: "Almost all of the physical distance indicators are standard candles" So the article has been enlightening but it also reinforced my point.

Quote:

The raw data are used together with cosmological models to deduce the rate of expansion. The type 1a supernovae data led inevitably to the conclusion that the rate of expansion is increasing. This work won a Nobel for Perlmutter, Schmidt and Riess in 2011.
[/quote]

Ok, there are two things to consider here: "Expansion" and "Red Shift". Red Shift is observed. Expansion is deduced.

I'm wondering what the problem is, then. The redshift is directly proportional to the observed distance, and the observed distance includes the distance an object has moved due to expansion. So why wouldn't a linear, non-accelerated, expansion work for that?
• October 5th, 2014, 01:03 PM
shlunka
Quote:

Originally Posted by tk421
Quote:

Originally Posted by kojax
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us...

You have oversimplified how it works to the point of caricature. Astrophysicicsts are not as foolish and naive as you seem to think. I recommend starting by reading the wiki entry on the cosmic distance ladder: Cosmic distance ladder - Wikipedia, the free encyclopedia

The raw data are used together with cosmological models to deduce the rate of expansion. The type 1a supernovae data led inevitably to the conclusion that the rate of expansion is increasing. This work won a Nobel for Perlmutter, Schmidt and Riess in 2011.

I envy the aptitude of astrophysicists, for my answer to the OP's question would be "The universe wasn't built with brakes." Now that that's out of the way, I don't think kojax was attempting an attack on the intelligence of astrophysicists, or any of those concerned with the observation/experimenting of cosmology.
• October 5th, 2014, 01:26 PM
Janus
Quote:

Originally Posted by kojax
There is a trend I'm seeing lately of people suggesting that if you question a physicist's conclusions, you're somehow also questioning whether they are "smart".

That's a bad trend to have in any scientific community because, first of all, smart people are wrong all the time, but second of all it make ad-hominem into the dominant rule of discourse.

"A smart person said it, therefore it must be true". Such rubbish.

A physicist can be mistaken, but that is not what you are suggesting. You are suggesting that all cosmologists are making the same mistake in the area of their own expertise. That they all are so incompetent in their jobs that they can't even work out the entire effect Doppler shift has on the observations.

It's like assuming that if you take your car in to every mechanic in the state to find out why the check engine light came on, that none of them would check to see if it was just a loose gas cap.
• October 5th, 2014, 05:59 PM
tk421
Quote:

Originally Posted by kojax
There is a trend I'm seeing lately of people suggesting that if you question a physicist's conclusions, you're somehow also questioning whether they are "smart".

If a lay person leaps to an ill-formed conclusion that is contrary to what has been worked out by experts, then that person is questioning the wrong people. That's all I'm saying.

Quote:

That's a bad trend to have in any scientific community because, first of all, smart people are wrong all the time, but second of all it make ad-hominem into the dominant rule of discourse.

"A smart person said it, therefore it must be true". Such rubbish.
You are arguing a straw man in an effort to avoid the core issue. To wit: We have you on one side of the argument, and Nobelists in the relevant field on the other side. I'm not saying that they are correct simply by virtue of being smart or having won an award. However, I am very definitely saying that you are being selectively skeptical in an unbalanced, and ultimately irrational, way. By questioning only the experts, you reveal a reliance on non-experts (you) over them.

Would you doubt neurosurgeons over a shaman?

That's the issue, kojax. It's a matter of likelihoods. The likelihood is very much that, if you disagree with experts who have devoted entire careers to studying a particular topic, you are wrong. That should be your default position.

Quote:

Originally Posted by kojax
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us...

You have oversimplified how it works to the point of caricature. Astrophysicicsts are not as foolish and naive as you seem to think. I recommend starting by reading the wiki entry on the cosmic distance ladder: Cosmic distance ladder - Wikipedia, the free encyclopedia

Quote:

Originally Posted by kojax
The linked wiki article had this to say about standard candles: "Almost all of the physical distance indicators are standard candles" So the article has been enlightening but it also reinforced my point.

It does no such thing. It simply says "we use standard candles." Your point is about how one uses standard candles, not the mere fact that we use them.

Here is a link to a highly readable article by Perlmutter. Perhaps it will help you understand how one uses standard candles in conjunction with models to perform the relevant calculations: http://supernova.lbl.gov/PhysicsTodayArticle.pdf
• October 6th, 2014, 09:18 PM
kojax
Quote:

Quote:

Originally Posted by tk421
"A smart person said it, therefore it must be true". Such rubbish.

You are arguing a straw man in an effort to avoid the core issue. To wit: We have you on one side of the argument, and Nobelists in the relevant field on the other side. I'm not saying that they are correct simply by virtue of being smart or having won an award. However, I am very definitely saying that you are being selectively skeptical in an unbalanced, and ultimately irrational, way. By questioning only the experts, you reveal a reliance on non-experts (you) over them.
I honestly couldn't care less who they are. Only what their evidence is.

Quote:

Would you doubt neurosurgeons over a shaman?
It would depend on how good the Shaman's evidence was.

However now you're effectively referring to me as the shaman. I'm not unskilled at math. I'm using the same tools and analytical process as the "doctor" is using.

Quote:

That's the issue, kojax. It's a matter of likelihoods. The likelihood is very much that, if you disagree with experts who have devoted entire careers to studying a particular topic, you are wrong. That should be your default position.
Do you refer to people who have memorized and now know how to regurgitate and equation, or people who actually know what the equation means? Can they tear it down to its nubbins and build it back up again, or are they just trusting some other "expert" who they believe to be smarter than them, who they are certain would not have made any mistakes setting up the problem?

Quote:

Quote:

Originally Posted by kojax
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us...

You have oversimplified how it works to the point of caricature. Astrophysicicsts are not as foolish and naive as you seem to think. I recommend starting by reading the wiki entry on the cosmic distance ladder: Cosmic distance ladder - Wikipedia, the free encyclopedia

Quote:

Originally Posted by kojax
The linked wiki article had this to say about standard candles: "Almost all of the physical distance indicators are standard candles" So the article has been enlightening but it also reinforced my point.

It does no such thing. It simply says "we use standard candles." Your point is about how one uses standard candles, not the mere fact that we use them.

Here is a link to a highly readable article by Perlmutter. Perhaps it will help you understand how one uses standard candles in conjunction with models to perform the relevant calculations: http://supernova.lbl.gov/PhysicsTodayArticle.pdf
Neither of these articles really say anything about the specific topic we're discussing.

This site suggests that astronomers use exactly the calculation I suggested they would use.

http://user.physics.unc.edu/~reichart/ASTR101L-5.pdf

as does this one.

http://www.astro.ex.ac.uk/people/hat...nr/candles.pdf

D = (L / 4πB)1/2

B being the observed brightness, L being the object's luminosity, and D being the expected distance. Basically they're using the equation for the surface area of a sphere, and assuming that the brightness would diminish by an inverse square law as the radius of the sphere grows.

And that calculation should be expected to yield the object's current distance, not its starting distance. Because the sphere grows both by way of light traveling through space, and by way of space itself expanding behind it.

Quote:

Originally Posted by Janus
Quote:

Originally Posted by kojax
There is a trend I'm seeing lately of people suggesting that if you question a physicist's conclusions, you're somehow also questioning whether they are "smart".

That's a bad trend to have in any scientific community because, first of all, smart people are wrong all the time, but second of all it make ad-hominem into the dominant rule of discourse.

"A smart person said it, therefore it must be true". Such rubbish.

A physicist can be mistaken, but that is not what you are suggesting. You are suggesting that all cosmologists are making the same mistake in the area of their own expertise. That they all are so incompetent in their jobs that they can't even work out the entire effect Doppler shift has on the observations.

It's like assuming that if you take your car in to every mechanic in the state to find out why the check engine light came on, that none of them would check to see if it was just a loose gas cap.

It wouldn't be the first time it has happened in history. Germany lost out on the atom bomb primarily because Heisenberg made the mistake of calculating the amount of U-235 needed for a chain reaction on the basis of an assumption that every neutron initially released would need to hit a nucleus.

It was an obvious and glaring error once someone pointed it out. Obviously you don't need an absolutely perfect initial chain reaction in order to create a big boom.

The guy who figured it out and passed on the information to the allies was actually just running equations in his spare time. He had been assigned to work on Radar instead, but got bored.
• October 8th, 2014, 05:23 PM
curious mind
Quote:

Originally Posted by kojax
Quote:

Quote:

Originally Posted by tk421
"A smart person said it, therefore it must be true". Such rubbish.

You are arguing a straw man in an effort to avoid the core issue. To wit: We have you on one side of the argument, and Nobelists in the relevant field on the other side. I'm not saying that they are correct simply by virtue of being smart or having won an award. However, I am very definitely saying that you are being selectively skeptical in an unbalanced, and ultimately irrational, way. By questioning only the experts, you reveal a reliance on non-experts (you) over them.
I honestly couldn't care less who they are. Only what their evidence is.

Quote:

Would you doubt neurosurgeons over a shaman?
It would depend on how good the Shaman's evidence was.

However now you're effectively referring to me as the shaman. I'm not unskilled at math. I'm using the same tools and analytical process as the "doctor" is using.

Quote:

That's the issue, kojax. It's a matter of likelihoods. The likelihood is very much that, if you disagree with experts who have devoted entire careers to studying a particular topic, you are wrong. That should be your default position.
Do you refer to people who have memorized and now know how to regurgitate and equation, or people who actually know what the equation means? Can they tear it down to its nubbins and build it back up again, or are they just trusting some other "expert" who they believe to be smarter than them, who they are certain would not have made any mistakes setting up the problem?

Quote:

Quote:

Originally Posted by kojax
All the observations of distance that are made of faraway objects are made using a "standard candle". Some object with a known, set luminosity, where the observed dimness of the object can be said to always be proportional to its distance away from us...

You have oversimplified how it works to the point of caricature. Astrophysicicsts are not as foolish and naive as you seem to think. I recommend starting by reading the wiki entry on the cosmic distance ladder: Cosmic distance ladder - Wikipedia, the free encyclopedia

Quote:

Originally Posted by kojax
The linked wiki article had this to say about standard candles: "Almost all of the physical distance indicators are standard candles" So the article has been enlightening but it also reinforced my point.

It does no such thing. It simply says "we use standard candles." Your point is about how one uses standard candles, not the mere fact that we use them.

Here is a link to a highly readable article by Perlmutter. Perhaps it will help you understand how one uses standard candles in conjunction with models to perform the relevant calculations: http://supernova.lbl.gov/PhysicsTodayArticle.pdf
Neither of these articles really say anything about the specific topic we're discussing.

This site suggests that astronomers use exactly the calculation I suggested they would use.

http://user.physics.unc.edu/~reichart/ASTR101L-5.pdf

as does this one.

http://www.astro.ex.ac.uk/people/hat...nr/candles.pdf

D = (L / 4πB)1/2

B being the observed brightness, L being the object's luminosity, and D being the expected distance. Basically they're using the equation for the surface area of a sphere, and assuming that the brightness would diminish by an inverse square law as the radius of the sphere grows.

And that calculation should be expected to yield the object's current distance, not its starting distance. Because the sphere grows both by way of light traveling through space, and by way of space itself expanding behind it.

Quote:

Originally Posted by Janus
Quote:

Originally Posted by kojax
There is a trend I'm seeing lately of people suggesting that if you question a physicist's conclusions, you're somehow also questioning whether they are "smart".

That's a bad trend to have in any scientific community because, first of all, smart people are wrong all the time, but second of all it make ad-hominem into the dominant rule of discourse.

"A smart person said it, therefore it must be true". Such rubbish.

A physicist can be mistaken, but that is not what you are suggesting. You are suggesting that all cosmologists are making the same mistake in the area of their own expertise. That they all are so incompetent in their jobs that they can't even work out the entire effect Doppler shift has on the observations.

It's like assuming that if you take your car in to every mechanic in the state to find out why the check engine light came on, that none of them would check to see if it was just a loose gas cap.

It wouldn't be the first time it has happened in history. Germany lost out on the atom bomb primarily because Heisenberg made the mistake of calculating the amount of U-235 needed for a chain reaction on the basis of an assumption that every neutron initially released would need to hit a nucleus.

It was an obvious and glaring error once someone pointed it out. Obviously you don't need an absolutely perfect initial chain reaction in order to create a big boom.

The guy who figured it out and passed on the information to the allies was actually just running equations in his spare time. He had been assigned to work on Radar instead, but got bored.

there's a difference whether an objects just gets dimmer by its fading light or by moving (expanding) away.
• October 8th, 2014, 06:59 PM
tk421
Quote:

Originally Posted by kojax
I honestly couldn't care less who they are. Only what their evidence is.

You are ignoring Janus' points in post #6. Of course individuals can be mistaken, but your argument isn't that. Your argument is that all of the experts (and yes, that's what they are) are making the same mistake.

And it's great that you say that you care only what their evidence is, but again, you're electing to ignore their collective assessment of the evidence and replace it with your own. I am not saying that it is impossible for you to be right and all of them wrong, but what I am trying to get you to acknowledge is that it is highly, extremely unlikely for that to be the case. It is far more likely that your lack of expertise in this area has led you to an erroneous conclusion. Remember, the experts have subjected their theories to peer review, part of which involves an assessment of alternative explanations, and an assessment of whether those have been properly considered by the authors.

Again, I'm talking about probabilities. And it is extremely, highly unlikely that a simple explanation of the type you propose actually works. Scientists routinely try simplest explanations first. They don't immediately leap to the most complex, obscurantist theories out of a love of complexity. They are generally dragged kicking and screaming toward complexity because the evidence compels them to do so.
• October 8th, 2014, 09:09 PM
kojax
Quote:

Originally Posted by tk421
Quote:

Originally Posted by kojax
I honestly couldn't care less who they are. Only what their evidence is.

You are ignoring Janus' points in post #6. Of course individuals can be mistaken, but your argument isn't that. Your argument is that all of the experts (and yes, that's what they are) are making the same mistake.

And over a billion people believe that Jesus Christ rose from the dead. If truth were a democracy, or if the number of adherents to a belief had any real correlation to the likelihood that said belief must be accurate, then I guess I'll go to hell when I die.

In the meantime, it's already fully understood that some part of the standard model must be wrong, or else QM and GR would match up better. The only question is where is the mistake? (Or mistakes, because there could be more than one.)

Quote:

And it's great that you say that you care only what their evidence is, but again, you're electing to ignore their collective assessment of the evidence and replace it with your own.
Assessments aren't evidence. They're just opinions.

Quote:

I am not saying that it is impossible for you to be right and all of them wrong, but what I am trying to get you to acknowledge is that it is highly, extremely unlikely for that to be the case. It is far more likely that your lack of expertise in this area has led you to an erroneous conclusion. Remember, the experts have subjected their theories to peer review, part of which involves an assessment of alternative explanations, and an assessment of whether those have been properly considered by the authors.
Look, if this position is wrong, it would trivially easy for any one of those experts to point it out, and explain why it is wrong. They might not be able to put the explanation into laymans' terms, but they'd have an explanation.

How about, instead of speculating as to what they would have to say, we let this thread stay open for a while and see if one of them shows up, and what they say?

The result could be very educational. At a minimum we would all understand the BBT better.

For that reason, there can be little doubt that my question is a good one to ask, nor can there be much doubt that waiting for an actual answer rather than just assuming the "experts are right", is the proper choice for me to make.
• October 8th, 2014, 09:55 PM
tk421
Quote:

Originally Posted by kojax
And over a billion people believe that Jesus Christ rose from the dead. If truth were a democracy, or if the number of adherents to a belief had any real correlation to the likelihood that said belief must be accurate, then I guess I'll go to hell when I die.

Oh, dear. Kojax, you are not paying attention at all.

Your refutation above is a response to a very thin straw man. You are comparing the beliefs of the faithful with the data-tested, peer-reviewed conclusions that have been vetted with the rigours of the scientific method. It is not democratic voting. If you are unable to see that your example has nothing whatever to do with the discussion taking place, I have nothing else to say. Perhaps that's just as well.

Quote:

In the meantime, it's already fully understood that some part of the standard model must be wrong, or else QM and GR would match up better. The only question is where is the mistake? (Or mistakes, because there could be more than one.)
That's actually not an accurate description. A better statement would be that it is understood that either QM or GR (or both) is incomplete. There is actually no experiment that shows a conflict.

But that's not relevant. If you were simply declaring that all scientific truths are provisional, then of course no scientist would disagree. But you are going further than that: You are saying that all astrophysicists have failed to consider how to calibrate expansion rates from known standard candles. That's remarkably unlikely. If you had said something sensible, such as "Maybe Type 1a supernovae come in more than one variety, so that the calibrations have relied on nonstandard standard candles," then many scientists would agree that such a thing is possible (but no evidence has yet emerged).

Quote:

Assessments aren't evidence. They're just opinions.
Of course they aren't evidence (and I did not say that they were -- note my careful wording). I do, however, strongly disagree that they're "just" opinions. You make it sound as if scientists just head off to the pub, get good and juiced up, then take a vote around the table. It's not nearly so casual, and your imputation simply reinforces the idea that you are ignorant of the amount of effort that is expended to perform these calculations based on the evidence and cosmological models.

Quote:

Look, if this position is wrong, it would trivially easy for any one of those experts to point it out, and explain why it is wrong. They might not be able to put the explanation into laymans' terms, but they'd have an explanation.

How about, instead of speculating as to what they would have to say, we let this thread stay open for a while and see if one of them shows up, and what they say?
I've never suggested that the thread be shut down, kojax. I don't know why you would react as if I had. I am happy to have this thread stay open as long as you want. All I am doing is pointing out that your speculations rely on a combination of naivete and a lack of understanding of how the mainstream became the mainstream.
• October 8th, 2014, 11:19 PM
tk421
As to how it has been determined that the expansion of the universe has accelerated, here's a capsule summary (from Saul Perlmutter's Nobel speech: http://www.nobelprize.org/nobel_priz...lecture.html):

1) We observe the redshift of supernovae (in the Nobel-winning work, the supernovae were Type 1a, which serve as reliable standard candles). That redshift tells us the expansion factor of the universe since the supernova went kablam!

2) We compute the expected brightness based on its present distance.

3) We compare that expected brightness with the actual brightness. If high redshift supernovae are dimmer than expected, then we know that expansion has accelerated. Similarly, if the high redshift supernovae are brighter than expected, then we know that expansion has decelerated.

Observations show that all high redshift Sn1a are dimmer than expected.

That's a highly simplified version, abstracted and extracted from Perlmutter's talk and accompanying slides (all available at the link given above). More maths are involved to do this right, but that's the outline.
• October 9th, 2014, 09:41 PM
kojax
Quote:

Originally Posted by tk421
As to how it has been determined that the expansion of the universe has accelerated, here's a capsule summary (from Saul Perlmutter's Nobel speech: http://www.nobelprize.org/nobel_priz...lecture.html):

I managed to find a PDF on that site, so I could read it. (My service provider I'm using right now doesn't allow streaming.)

http://www.nobelprize.org/nobel_priz...er-lecture.pdf

However he doesn't appear to go into detail about his calculations anywhere in the lecture. His observational work is certainly impressive. He should be right up there with Tycho Brahe for that. But none of this guarantees he was using a correct distance calculation. Even if he hadn't been, his work would still be useful, and would have generated results.

Brahe thought he was observing a geocentric solar system.

Quote:

Originally Posted by tk421
Quote:

Originally Posted by kojax
And over a billion people believe that Jesus Christ rose from the dead. If truth were a democracy, or if the number of adherents to a belief had any real correlation to the likelihood that said belief must be accurate, then I guess I'll go to hell when I die.

Oh, dear. Kojax, you are not paying attention at all.

Your refutation above is a response to a very thin straw man. You are comparing the beliefs of the faithful with the data-tested, peer-reviewed conclusions that have been vetted with the rigours of the scientific method. It is not democratic voting. If you are unable to see that your example has nothing whatever to do with the discussion taking place, I have nothing else to say. Perhaps that's just as well.

The problem is that you are treating errors of execution the same as errors in planning. Planning tends to be carried out by just a few people. They come up with the outline, and the rest just execute it.

It's kind of like the pyramids of Egypt. Certainly thousands of workers were involved in building the bent pyramid, but it still ended up bent.

Why? Well, clearly the reason is because, while there might have been thousands of people cutting and setting the stones, most of them were doing so from a vantage where they really don't spend much time examining the overall design of the pyramid. They're not asking themselves whether the stones at the bottom will be able to support X amount of weight above them. They're just trying to cut their stone so it fits the specification.

The people applying the distance calculation have no reason to question its validity, so they would probably never even trouble themselves to see if it is right. Their focus is usually going to be on smaller sub-problems, like trying to find a more reliable supernova to use.

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Look, if this position is wrong, it would trivially easy for any one of those experts to point it out, and explain why it is wrong. They might not be able to put the explanation into laymans' terms, but they'd have an explanation.

How about, instead of speculating as to what they would have to say, we let this thread stay open for a while and see if one of them shows up, and what they say?
I've never suggested that the thread be shut down, kojax. I don't know why you would react as if I had. I am happy to have this thread stay open as long as you want. All I am doing is pointing out that your speculations rely on a combination of naivete and a lack of understanding of how the mainstream became the mainstream.
Well..... it kind of sounds like you're accusing me of being a crank. And crank threads tend to get shut down.

So it's important to be clear that I am not failing to provide evidence, and not ignoring evidence that other posters present.

Or well, with one exception: I don't think that I am obligated to accept an argument from consensus. I shouldn't have to treat that as if it were reliable evidence on a hard science sub-forum.
• October 9th, 2014, 10:23 PM
tk421
Quote:

Originally Posted by kojax
Quote:

Originally Posted by tk421
As to how it has been determined that the expansion of the universe has accelerated, here's a capsule summary (from Saul Perlmutter's Nobel speech: http://www.nobelprize.org/nobel_priz...lecture.html):

I managed to find a PDF on that site, so I could read it. (My service provider I'm using right now doesn't allow streaming.)

http://www.nobelprize.org/nobel_priz...er-lecture.pdf

However he doesn't appear to go into detail about his calculations anywhere in the lecture.

You need to understand a couple of things that you keep ignoring. Sorry for the terseness, but my natural verbosity has apparently made things insufficiently clear:

A Nobel lecture is not the same as a peer-reviewed publication. It is intended for a general audience. The reason for linking to the lecture is to get you to start doing some actual research into what the mainstream is. You cannot legitimately question the mainstream position without knowing how it became the mainstream position. The fact that you had not even bothered to hunt down Perlmutter's lay-level Nobel talk is part of what I'm talking about when I call your attitude naive. If you were truly interested in finding out what the situation is, you would use your google powers to find Perlmutter's peer-reviewed publications (and the papers they refer to, etc.), where the detailed calculations are spelled out.

Don't be lazy and "wait for one of" those astrophysicists to appear here to explain themselves to you. Do some work yourself.

Quote:

Or well, with one exception: I don't think that I am obligated to accept an argument from consensus. I shouldn't have to treat that as if it were reliable evidence on a hard science sub-forum.
Please stop the strawman bs. It's tiresome and offensive. I repeat again: I am not saying you are obligated to accept an argument from consensus. That is your continued strawman. I understand why you woud keep using this tactic, as it deflects attention away from what I actually am saying.

And to remind you, what I am saying is this:

To believe that scientists who are dedicated to this field of study have committed the same, obvious blunder is to believe in such a highly improbable occurrence that you are obligated to consider more probable explanations. One of those more probable explanations is that it is you who are in error because you have not even studied how these scientists drew the conclusions that they have.

I am not saying that they are correct by consensus. I am not saying that you are obligated to accept their arguments just because they all agree with each other. I am, once again, talking about probabilities.

Now that I have clarified my statements for the third time, I ask that you desist from mischaracterising my position again.
• October 10th, 2014, 01:52 AM
kojax
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Originally Posted by tk421
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Originally Posted by kojax
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Originally Posted by tk421
As to how it has been determined that the expansion of the universe has accelerated, here's a capsule summary (from Saul Perlmutter's Nobel speech: http://www.nobelprize.org/nobel_priz...lecture.html):

I managed to find a PDF on that site, so I could read it. (My service provider I'm using right now doesn't allow streaming.)

http://www.nobelprize.org/nobel_priz...er-lecture.pdf

However he doesn't appear to go into detail about his calculations anywhere in the lecture.

You need to understand a couple of things that you keep ignoring. Sorry for the terseness, but my natural verbosity has apparently made things insufficiently clear:

A Nobel lecture is not the same as a peer-reviewed publication. It is intended for a general audience. The reason for linking to the lecture is to get you to start doing some actual research into what the mainstream is. You cannot legitimately question the mainstream position without knowing how it became the mainstream position. The fact that you had not even bothered to hunt down Perlmutter's lay-level Nobel talk is part of what I'm talking about when I call your attitude naive. If you were truly interested in finding out what the situation is, you would use your google powers to find Perlmutter's peer-reviewed publications (and the papers they refer to, etc.), where the detailed calculations are spelled out.

Don't be lazy and "wait for one of" those astrophysicists to appear here to explain themselves to you. Do some work yourself.

I've been finding that the problem is, advanced papers assume everyone knows what calculation they are using. Popular essays, lectures, or papers assume the audience will be too stupid to understand if they try to explain the calculation they are using. It's like looling for a needle in a haystack. Not like I haven't been looking.

However, since it appears that neither of us actually know how they calculate it for sure (except my sources that suggest they use an inverse square law), you're asking me to believe something without evidence by insisting that this unknown calculation will turn out to include expansion driven dimming.

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Or well, with one exception: I don't think that I am obligated to accept an argument from consensus. I shouldn't have to treat that as if it were reliable evidence on a hard science sub-forum.
Please stop the strawman bs. It's tiresome and offensive. I repeat again: I am not saying you are obligated to accept an argument from consensus. That is your continued strawman. I understand why you woud keep using this tactic, as it deflects attention away from what I actually am saying.

And to remind you, what I am saying is this:

To believe that scientists who are dedicated to this field of study have committed the same, obvious blunder is to believe in such a highly improbable occurrence that you are obligated to consider more probable explanations. One of those more probable explanations is that it is you who are in error because you have not even studied how these scientists drew the conclusions that they have.
I already gave you an example from history where an exactly identical blunder happened and an equally large number of specialists failed to see it for years.

The idea that such things can happen is backed up by the fact that it has happened.

I also explained why it happens, and how your visioin of events is a fantasy. Just because thousands of people use a formula dosen't mean thousands of people have reviewed that formula for accuracy.

You've got this imaginary construct built up in your mind of a "specialist" as someone who always looks into every detail of everything they do. When in real life, most specialists are focused on an immediate task at hand.
• October 10th, 2014, 06:26 AM
tk421
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Originally Posted by kojax
I already gave you an example from history where an exactly identical blunder happened and an equally large number of specialists failed to see it for years.

Your example of Heisenberg's error isn't relevant at all.

If my statement had been "scientists are inerrantly perfect," then it would have. But that's not what I've been saying.

Heisenberg did not publish his work on the atom bomb in the open literature. There weren't peer-reviewed papers studied and critiqued by the entire community of nuclear physicists. That entire community had not made the same error.

Indeed, Heisenberg was the minority figure, while the vast majority (who were then in the US) had it right. If we are to apply that example to the current argument, we would have to cast you in the role of Heisenberg. Your example thus does not refute my argument; indeed, it supports it.

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The idea that such things can happen is backed up by the fact that it has happened.
You'll have to find another example, because the one you provided doesn't support at all what you are claiming.

Find an example that meets the same criteria as fit accelerated universal expansion:

1) The work has been peer-reviewed.
2) The work is of widespread interest, and so has attracted intense scrutiny by a wide audience.
3) The work has survived this scrutiny and critical review. This wider audience has replicated the results.

Your example does not meet these criteria. Again, the argument is not that scientists are perfect, so you'll have to stop using straw man arguments.

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I also explained why it happens, and how your visioin of events is a fantasy. Just because thousands of people use a formula dosen't mean thousands of people have reviewed that formula for accuracy.
So far, you've only been arguing a strawman cartoon caricature of what I am actually saying.

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You've got this imaginary construct built up in your mind of a "specialist" as someone who always looks into every detail of everything they do. When in real life, most specialists are focused on an immediate task at hand.
Again, you seem to be deliberately misstating my position. I finid it curious that you seem to have such a need to do so. Your attitude is very much like that of relativity deniers: "Well, Einstein could be wrong." That is trivially true, of course, but that is not the argument. For the umpteenth time, the argument is that it is highly unlikely that something of such widespread interest could have an undetected, trivial flaw at the level you are claiming, after having been studied widely by a large community of experts over a century.

I propose that you are the one who has the "imaginary construct" that is distorted.

Since it appears that you haven't even read Perlmutter's papers, you haven't done the requisite minimum homework to conclude that he and all other astrophysicists have blundered together in the uniform and trivial way you are claming.
• October 10th, 2014, 08:45 AM
kojax
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Originally Posted by tk421

If my statement had been "scientists are inerrantly perfect," then it would have. But that's not what I've been saying.

Why don't you state your position more clearly if you want people to understand it.

The question I am posing has not been directly reviewed by more than just the barest minority of scientists. Just because a scientist applies or makes use of a formula doesn't automatically mean they've critically examined it.

You may turn the ignition on your car every morning to start it. That doesn't automatically mean you know how your car works or why,. Your car is a tool. Just like how a formula is a tool. Using the tool doesn't impart any special knowledge about its inner workings.

You appear to be trying to imagine that it does, or that the majority of physicists have looked into this formula, beyond the basic requirement to learn it for their classes so they could graduate from college.

Why don't you try to explain how that assessment is inaccurate, and why you think thousands of people's collective lack of objection to something the vast majority of them have never even looked into is a strong reason for me to doubt my position?

You can't really accuse people of misstating your position if you wont' even go to the trouble of stating it clearly to begin with.

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Heisenberg did not publish his work on the atom bomb in the open literature. There weren't peer-reviewed papers studied and critiqued by the entire community of nuclear physicists. That entire community had not made the same error.

Indeed, Heisenberg was the minority figure, while the vast majority (who were then in the US) had it right. If we are to apply that example to the current argument, we would have to cast you in the role of Heisenberg. Your example thus does not refute my argument; indeed, it supports it.
Heisenberg was part of the Vienna Circle. So while his theory was not, and could not be, widely published due to its classified nature, most of the members of the scientific community who needed to be concerned with it were fully aware of his work. Almost certainly including Einstein, for that matter.

Vienna Circle - Wikipedia, the free encyclopedia

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The idea that such things can happen is backed up by the fact that it has happened.
You'll have to find another example, because the one you provided doesn't support at all what you are claiming.

Find an example that meets the same criteria as fit accelerated universal expansion:

1) The work has been peer-reviewed.
2) The work is of widespread interest, and so has attracted intense scrutiny by a wide audience.
3) The work has survived this scrutiny and critical review. This wider audience has replicated the results.

Your example does not meet these criteria. Again, the argument is not that scientists are perfect, so you'll have to stop using straw man arguments.
Now you're just trying to set your own goal posts.

And throw around the word "straw man" in a way that kind of makes it sound like you don't know what the phrase means.
• October 10th, 2014, 12:18 PM
tk421
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Originally Posted by kojax
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Originally Posted by tk421

If my statement had been "scientists are inerrantly perfect," then it would have. But that's not what I've been saying.

Why don't you state your position more clearly if you want people to understand it.

I have stated it clearly at least three times now. Sometimes the problem is not in the writing, but in the reading. My previous posts still stand, unedited. You -- and anyone else -- may see what I have written previously. I assert with confidence that anyone with a basic command of the English language (even of the Amercian language, for that matter) will see that I have been clear and consistent about what my position has been all along. It has not changed.

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The question I am posing has not been directly reviewed by more than just the barest minority of scientists. Just because a scientist applies or makes use of a formula doesn't automatically mean they've critically examined it.
You are simply making self-serving statements out of ignorance of the mainstream theory. You need to develop a habit of self-skepticism if you are to succeed in any scientific endeavour. It is not sufficient merely to be skeptical of everyone else. You must include yourself. In this case, your failure to study has caused you to blunder badly yet again.

The use of standard candles in distance calculations is an old, incredibly well-studied art, dating back at least to Baade's work shortly after WWII. Perlmutter did not invent the method. What he did do, and what he won his Nobel for doing, was to figure out a practical way to catch enough Type 1a supernovae in the act of going nova to serve as such candles.

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You may turn the ignition on your car every morning to start it. That doesn't automatically mean you know how your car works or why,. Your car is a tool. Just like how a formula is a tool. Using the tool doesn't impart any special knowledge about its inner workings.
All true, and all completely irrelevant. Focus, man, focus!

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Heisenberg was part of the Vienna Circle. So while his theory was not, and could not be, widely published due to its classified nature, most of the members of the scientific community who needed to be concerned with it were fully aware of his work. Almost certainly including Einstein, for that matter.
Good, so you acknowledge that it was not widely published. You linked to site that describes the Vienna Circle, so you know also that Heisenberg's detailed work -- the stuff he got wrong -- was not circulated because these were state secrets. Speculating about Einstein sounds like a desperate appeal to authority. There is no evidence that Einstein was aware of anything quantitative about what the Germans were doing during the War. Finally, the fact that Heisenberg was in error became obvious even to Heisenberg in August of 1945.

All of that history makes your example completely irrelevant as a comparison, except possibly as an object lesson on the value of peer review, and the dangers of not subjecting one's ideas to it.

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And throw around the word "straw man" in a way that kind of makes it sound like you don't know what the phrase means.
Your strawman arguments don't persuade, and your canard that the term's meaning is unfamiliar to me confirms that you have no rational refutations of what I've been saying. Remember the Black Knight.
• October 10th, 2014, 08:19 PM
kojax
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Originally Posted by tk421
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The question I am posing has not been directly reviewed by more than just the barest minority of scientists. Just because a scientist applies or makes use of a formula doesn't automatically mean they've critically examined it.
You are simply making self-serving statements out of ignorance of the mainstream theory. You need to develop a habit of self-skepticism if you are to succeed in any scientific endeavour. It is not sufficient merely to be skeptical of everyone else. You must include yourself. In this case, your failure to study has caused you to blunder badly yet again.

Failure to study what?

You don't appear to be able to find a reliable source stating what calculation is used either. Teapot - Kettle.

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The use of standard candles in distance calculations is an old, incredibly well-studied art, dating back at least to Baade's work shortly after WWII. Perlmutter did not invent the method. What he did do, and what he won his Nobel for doing, was to figure out a practical way to catch enough Type 1a supernovae in the act of going nova to serve as such candles.
And all this I understand perfectly. Absolutely, crystal, clear.

The problem is whenever I research the topic, all I get is non-stop repetitions of this same information. Again and again, but never anywhere does a reliable source state what calculation is being used AFTER a standard candle is identified.

This is why I keep bringing up Tycho Brahe. He was able to make incredibly accurate observations even though he was working from a flawed theory. (He believed in a geo-centric solar system.)

I don't see any contradiction between the high degree of accuracy of Perlmutter's work and the possibility he might be working from an innacurate calculation. Both possibilities can coexist.

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You may turn the ignition on your car every morning to start it. That doesn't automatically mean you know how your car works or why,. Your car is a tool. Just like how a formula is a tool. Using the tool doesn't impart any special knowledge about its inner workings.
All true, and all completely irrelevant. Focus, man, focus!
I'm trying to help you understand that, when physicists make use of a formula, it is every bit as much a tool to them as your automobile is to you.

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Heisenberg was part of the Vienna Circle. So while his theory was not, and could not be, widely published due to its classified nature, most of the members of the scientific community who needed to be concerned with it were fully aware of his work. Almost certainly including Einstein, for that matter.
Good, so you acknowledge that it was not widely published. You linked to site that describes the Vienna Circle, so you know also that Heisenberg's detailed work -- the stuff he got wrong -- was not circulated because these were state secrets. Speculating about Einstein sounds like a desperate appeal to authority.
Einstein was something of a conduit for other scientists to get their ideas out there. For example, when L'Maitre offered up the BBT hypothesis in the first place, he did it by writing to Einstein, who then passed it on to have it published.

I'm just thinking that if he knew about it, then he likely told others about it.

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There is no evidence that Einstein was aware of anything quantitative about what the Germans were doing during the War. Finally, the fact that Heisenberg was in error became obvious even to Heisenberg in August of 1945.

You mean when the allies bombed Hiroshima on August 6th of that year?

Yeah..... that would tend to make it obvious.

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And throw around the word "straw man" in a way that kind of makes it sound like you don't know what the phrase means.
Your strawman arguments don't persuade, and your canard that the term's meaning is unfamiliar to me confirms that you have no rational refutations of what I've been saying. Remember the Black Knight.
I'm not entirely confident that I am straw manning you at all. Am I putting foolish words in your mouth? Arguing that you are arguing something and then refuting your arguments you haven't made?

Using analogies to try and help you understand why the mechanics of the situation don't necessarily work the way you think they work... - that is not straw manning.

It seems to me that you are attempting to make an argument from probability. However it is very important whem making arguments of that nature, to be certain that odds really line up the way you think they do. You have to use a proper, probabalistic and/or statistical approach, and that means making an honest assessment of what kind of "dice" are being rolled here, and how likely it is that those dice will truly land on the numbers you expect them to land on.

If every scientist in the group were picking through the formula with a fine toothed comb, looking for possible errors, then maybe the odds against this would be staggering. But that doesnt' appear to be the case. The BBT in general started out as a kind of fringe hypothesis. Something interesting, maybe even possible, but not necessarily convincing. Most of its groundwork was laid during that time, when it was just harmless speculation. It was only after the discovery of the CMBR confirmed one of its more exotic predictions that the theory became serious business.
• October 11th, 2014, 12:19 AM
GTCethos
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Therefore, there is no need for an accelerated expansion. If we're seeing our candles at the distance where they have arrived at now, then we don't need to account for how far they must have moved before the light could reach us. That has already been accounted for by the dimness of the light.

So you are not a fan of Hubble.

I think that it might be time to consider an alternative to BB cosmology. I am a big fan of relativity (even though I am not the sharpest tool in the shed).

As far as I can determine there are over 300 alternative cosmologies proposed by broader astrophysics.

If anyone here might have the slightest interest, here is a paper promoting Cosmological relativity. No dark matter in spiral galaxies or larger scales in the universe.http://arxiv.org/pdf/astro-ph/0501526v6.pdf

The key to Cosmological Relativity is that there is no absolute cosmic time, although any observer at any point in space and at any time will see τ = 13.56 Gyr. Cosmological relativity - CreationWiki, the encyclopedia of creation science
• October 11th, 2014, 12:26 AM
tk421
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Originally Posted by kojax
You don't appear to be able to find a reliable source stating what calculation is used either. Teapot - Kettle.

Sorry, but it's not quite as simple as you'd like it to be. The hard part for you is that the burden is on you, not the mainstream. I've already given you plenty of pointers of where to look. Google is your friend. Baade's papers (and the ones he references). Textbooks. Perlmutter (and the papers he references in his papers). It's not my job to do your work for you.

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The problem is whenever I research the topic, all I get is non-stop repetitions of this same information. Again and again, but never anywhere does a reliable source state what calculation is being used AFTER a standard candle is identified.
I don't think you have looked hard at all. Given that I had to lead you to Perlmutter's Nobel talk, it would seem that you haven't done even a basic dive into the literature.

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This is why I keep bringing up Tycho Brahe. He was able to make incredibly accurate observations even though he was working from a flawed theory. (He believed in a geo-centric solar system.)
And you've drawn poor parallels with that history. Brahe made excellent observations, and those observations fit his geo-heliocentric model very well. There was no error. By the standards of science, what he did was perfectly fine. It took more than a century before additional observations (chiefly of stellar aberration) finally provided data that showed Brahe's model to be unworkable.

In short, there was no error in any calculation anywhere. His science was sound, given the observations he had at his disposal.

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I don't see any contradiction between the high degree of accuracy of Perlmutter's work and the possibility he might be working from an innacurate calculation. Both possibilities can coexist.
Kojax, it is extremely frustrating to have to make the same point over and over again. This is what I mean by "straw man": Your attempts at refutation are all basically of the form "scientists can make a mistake." I've already stipulated to that many times, and I've also pointed out many times that this has nothing to do with my position.

You bring up Brahe, but as I've just shown you, Brahe made no errors in observation, nor in calculation.

Instead of speculating and asserting, just LOOK AT THE LITERATURE. In the time you've spent mounting irrelevant arguments, you could have found a lot of useful information.

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I'm trying to help you understand that, when physicists make use of a formula, it is every bit as much a tool to them as your automobile is to you.
Again, you're not saying anything relevant to any point I've made.

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Einstein was something of a conduit for other scientists to get their ideas out there. For example, when L'Maitre offered up the BBT hypothesis in the first place, he did it by writing to Einstein, who then passed it on to have it published. I'm just thinking that if he knew about it, then he likely told others about it.
You're making stuff up again, kojax. During WWII, Heisenberg was very much cut off from the rest of his former colleagues. Germany was at war with the US, remember? Even his old friend, Bohr, flew into a rage when Heisenberg came to call on him and informed Bohr of his work on the German bomb. That Bohr didn't know about Heisenberg's involvement tells you all you need to know about your claims that Heisenberg's A-bomb work was circulated widely outside of a very tight circle in Germany during the war.

In short, your claim makes no sense, has zero evidentiary support, and is contradicted by documented events such as I've just cited.

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It seems to me that you are attempting to make an argument from probability.
Glad that, after multiple posts in which I have put the word probability in italics (and probably boldfaced, too), you've finally noticed.

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However it is very important whem making arguments of that nature, to be certain that odds really line up the way you think they do. You have to use a proper, probabalistic and/or statistical approach, and that means making an honest assessment of what kind of "dice" are being rolled here, and how likely it is that those dice will truly land on the numbers you expect them to land on.
No, none of that is really necessary in a case like this, because it's so far away from a judgment call. If I were to jump off the roof of a skyscraper, I would probably die. I don't need to carry out any probabilistic calculation to reach a high-fidelity conclusion.

Similarly, if I have an amateur who hasn't even bothered to study the literature in anything but a cursory fashion, yet has proclaimed not only that a Nobel-prize winner's work is in error -- a trivial blunder that has eluded notice despite decades of work by countless researchers toiling away on a topic of intense, widespread interest -- then no calculation is necessary.

To supplement that conclusion, I note the absence of a single example of anything remotely comparable happening within the last century. Your best shot was Heisenberg, and that example was a complete bust, as I've shown. Indeed, the example reinforces, not refutes, my point.

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If every scientist in the group were picking through the formula with a fine toothed comb, looking for possible errors, then maybe the odds against this would be staggering. But that doesnt' appear to be the case.
That appearance is what it is because you haven't seriously looked at how many fine-toothed combs were involved. You seem curiously reluctant to dive into the literature with the zeal one would expect of someone who professes such interest in the topic.

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The BBT in general started out as a kind of fringe hypothesis. Something interesting, maybe even possible, but not necessarily convincing. Most of its groundwork was laid during that time, when it was just harmless speculation. It was only after the discovery of the CMBR confirmed one of its more exotic predictions that the theory became serious business.
Yes, it's called the scientific method. And until there was compelling evidence, BBT had to compete with its rivals. Once high-fidelity evidence showed up, scientists were able to discriminate among the contestants. BBT won.

Do you understand the lessons of that history? Nowhere in that story was there a persistent blunder made by essentially the entire community that went undetected or uncritiqued for decades. Nowhere in that story was there an amateur who hadn't studied the literature, and yet who fixed the errors.

In short, the example you bring up not only fails to refute anything I've been saying, it reinforces my position.