Evolution Demonstrated In A Laboratory

[Bomb#20]

There were many estimations of the size of the Earth in the time of Columbus. Many wrong. Columbus very well knew of Eratosthenes estimate, but discounted it because it meant that Columbus could not reach India from Portugul. His ships were in serious trouble when he finally hit land, which was not India. Columbus was a lucky fool.

True that. Also keep in mind there was no way to measure longitude, so nobody knew how big Asia was. Dead reckoning and reading Marco Polo's memoirs doesn't give you much accuracy. Columbus didn't just underestimate the earth, but also overestimated Asia.

 

[Bomb#20]

But what about Ptolemey’s geocentric model? Surely it was “grossly contrary” to reality, and yet it worked just fine and dandy for navigation and other calculational purposes for over a thousand years.

Keep in mind that Ptolemy’s geocentric model isn’t a simplified version of a heliocentric model the way that Newton’s Laws are of Einstein’s. The so-called “wrongness” is categorically different. Like Bomb’s mention of flat earth, which also isn’t a simplified version of the globe earth model. It is wrong at a foundational level. That’s not what is happening with Newton and Einstein.

What makes the wrongness of flat-earth "foundational", and why isn't the wrongness of Newton similarly "foundational"? I don't understand the distinction you're drawing. If a simplified version of the globe earth model isn't the flat earth, what is? You get flat earth from globe earth by setting the curvature to zero; you get Newton's gravity from General Relativity by setting the curvature to zero. Newtonian mechanics assumes absolute earlier and later instead of having them observer-relative; flat earth assumes absolute up and down instead of having them observer-relative. Taylor-expand Einstein and the first terms recreate Newton; Taylor-expand globe earth and the first terms recreate flat earth.

I take it you feel "wrongness" forms a tree of the form [Newton, [Ptolemy, Flat-earth]]. It seems painfully obvious to me that the more reasonable wrongness tree is [Ptolemy, [Newton, Flat-earth]]. If you have a metric that accounts for grouping flat-earth with Ptolemy rather than with Newton apart from our cultural tradition of using flat-earthers as our go-to example of idiots, please explain it.

 

[Shadowy Man]

But what about Ptolemey’s geocentric model? Surely it was “grossly contrary” to reality, and yet it worked just fine and dandy for navigation and other calculational purposes for over a thousand years.

Keep in mind that Ptolemy’s geocentric model isn’t a simplified version of a heliocentric model the way that Newton’s Laws are of Einstein’s. The so-called “wrongness” is categorically different. Like Bomb’s mention of flat earth, which also isn’t a simplified version of the globe earth model. It is wrong at a foundational level. That’s not what is happening with Newton and Einstein.

What makes the wrongness of flat-earth "foundational", and why isn't the wrongness of Newton similarly "foundational"? I don't understand the distinction you're drawing. If a simplified version of the globe earth model isn't the flat earth, what is?

You get flat earth from globe earth by setting the curvature to zero;

No. You don’t. That’s not what “flat earth” is.

This is becoming too distracting a detail of this thread but before you decide what you’ve suggested here is a good line of argument, please go find out what the flat earth model is.

Hopefully then after considering that and then fully understanding the relationship between Newtonian and Einsteinian gravities you’ll come to understand my point.

An internet thread is not a good place for a physics lesson. Maybe someone else can do a better job of it but I don’t think I will be successful. That’s more a comment on my ability to communicate my point in this venue than any issue with the physics.

 

[pood]

Yes, I agree entirely. My raising the geocentric model of Ptolemy was in response to you correctly pointing out that the flat earth model was not only “grossly contrary” to reality, but easily disprovable because it made false predictions.

Say what?!? How the bejesus do you figure a theory making false predictions implies it's easily disprovable?

How the bejeezus did you come up with the idea that I said that? I said just the opposite, citing the success of the Ptolemaic system for over a thousands years.

However, SOME theories grossly at odds with reality are easily disprovable, the flat earth being one. As you yourself point out, Iron Age sailors would have certainly known that the earth was round. I don’t know about ancient farmers, but then again I doubt very many of them were making “models” of the world in scientific sense we mean today. By antiquity, the Greeks not only knew the world was round, but they roughly estimated its diameter.

But yes, farmers back then, and even now, could do just fine with a flat-earth model. When you calculate the area of your plot of land, for example, you don’t need to take into account the earth’s curvature, since locally it is minuscule.

As to heliocentriism and the church, I agree that the church had good reasons to oppose or at least cast doubt on the heliocentrism of Copernicus, and not all of them related to Scripture, either. The success for more than a thousand years of the predictive model of Ptolemy would have created an inertia in its favor, a reluctance to scrap it, which we often see today when scientists hold on to theories even sometimes in the face of falsifications. When Einstein was asked what he would think if his relativity theory were falsified, he said that he should feel sorry for the dear lord, because the theory was correct.

Also, the church didn’t really forbid Galileo from teaching heliocentrism as a calculational tool. They just didn’t want him to teach it as true. Heliocentrism eventually carried the day not only because of its predictive success but because of empirical verification, like the phases of Venus, impossible under Ptolemy’s system.

As to Newton and Einstein, I think you are making a mountain out of a molehill. Shadowy Man already explained why. We can use Newton just fine at the coarse-grained, classical level, abstracting out the annoying superfluities of relativity and QM for those purposes, the point Shadowy Man made.

You seem not to have noticed that I’m actually agreeing with you, to a point. It was I who mentioned theory underdetermination, the idea that theories are underdetermined by data. Take your iron-age sailors. There are several ways that they would have deduced that the world was round, one being that when they stood on shore, they would have noticed that boats nearing the horizon begin to sink below it, which is consistent with a round earth, rather than dwindling to a distant point, consistent with a flat earth. However, some sharpie back then could have offered an alternative theory: that light, when seen from a far distance, begins to bend or curve, and does so in such a way that it creates the optical illusion that boats were sinking below the horizon, when really they were dwindling to a point. Ergo, the earth is flat after all, and who could have disproved such a theory back then, given that they knew next to nothing about how light really behaves?

 

[Bomb#20]

Yes, I agree entirely. My raising the geocentric model of Ptolemy was in response to you correctly pointing out that the flat earth model was not only “grossly contrary” to reality, but easily disprovable because it made false predictions.

Say what?!? How the bejesus do you figure a theory making false predictions implies it's easily disprovable?

How the bejeezus did you come up with the idea that I said that?

By reading what you said! You said "easily disprovable because it made false predictions"! What the heck did you mean by those words, if a theory making false predictions doesn't imply it's easily disprovable?!?

I said just the opposite, citing the success of the Ptolemaic system for over a thousands years.

Indeed. You appear to have applied contradictory premises.

However, SOME theories grossly at odds with reality are easily disprovable, the flat earth being one.

Right; but "it made false predictions" is plainly not the reason it's easily disprovable. The Ptolemaic system made false predictions but is not easily disprovable. Newtonian mechanics made false predictions but is not easily disprovable. Either QM or GR makes false predictions but is not easily disprovable. So what is it about flat earth that makes it easily disprovable?

As you yourself point out, Iron Age sailors would have certainly known that the earth was round.

Actually, Iron Age sailors would have certainly had what they needed to figure out that the earth was round but the historical record shows it was not until very late in the Iron Age that the Greeks started to put it together. Aristotle knew the earth was round but Homer had no idea. (Moreover, Iron Age sailing wasn't confined to Greeks but the rest of the world took even longer to realize the earth was round.)

I don’t know about ancient farmers, but then again I doubt very many of them were making “models” of the world in scientific sense we mean today. By antiquity, the Greeks not only knew the world was round, but they roughly estimated its diameter.

"The Greeks" is of course an overgeneralization -- lots of Greeks knew it; lots of other Greeks didn't. The theory remained controversial among the educated for hundreds of years. As far as estimating its diameter goes, funny story about that. Chinese geographers stuck with the flat earth model right up into the early modern era of contact with European sailors, even though they were perfectly aware of the variation in angle to the sun with latitude that Eratosthenes had used to roughly estimate its diameter. The Chinese took the variation to be the result of the sun not being all that far away. So they used their Eratosthenes-style measurements to spuriously calculate the distance to the sun. Proving that explanation wrong was not so easy.

When Einstein was asked what he would think if his relativity theory were falsified, he said that he should feel sorry for the dear lord, because the theory was correct.

That's beautiful!

As to Newton and Einstein, I think you are making a mountain out of a molehill.

Who, me? It was SM who made this mountain out of this molehill -- he raised the big fuss over our differing usages of "wrong". The primary issue is that bilby's and the OP's arguments against theism don't work for reasons explained upthread; you and SM don't appear to have disputed that.

Shadowy Man already explained why. We can use Newton just fine at the coarse-grained, classical level, abstracting out the annoying superfluities of relativity and QM for those purposes, the point Shadowy Man made.

Yes, of course; and likewise, if there's some so-called god messing with people, we have no reason to think that we couldn't likewise use relativity and QM just fine at the coarse-grained, scientific level, abstracting out the annoying superfluities of an alien life form hiding its messing with people in those same annoying superfluities.

You seem not to have noticed that I’m actually agreeing with you, to a point.

But I did notice that. Noticing that is precisely why I was so gobsmacked when I also saw you use the phrase "easily disprovable because it made false predictions".

It was I who mentioned theory underdetermination, the idea that theories are underdetermined by data. Take your iron-age sailors. There are several ways that they would have deduced that the world was round, one being that when they stood on shore, they would have noticed that boats nearing the horizon begin to sink below it, which is consistent with a round earth, rather than dwindling to a distant point, consistent with a flat earth. However, some sharpie back then could have offered an alternative theory: that light, when seen from a far distance, begins to bend or curve, and does so in such a way that it creates the optical illusion that boats were sinking below the horizon, when really they were dwindling to a point. Ergo, the earth is flat after all, and who could have disproved such a theory back then, given that they knew next to nothing about how light really behaves?

Excellent example. This is why I don't understand why you guys seem to regard the flat earth theory as foolishness on a level with Ptolemaic astronomy. Looks to me like a perfectly reasonable theory for its time, that's still perfectly sensible to use in a limited domain such as getting permits from the county planning office, and is merely past its sell-by date as a description of the world as a whole -- the same thing Newtonian physics is, just with a two-million-times-smaller useful domain and a two-thousand-year-earlier sell-by date.

 

[Bomb#20]

Keep in mind that Ptolemy’s geocentric model isn’t a simplified version of a heliocentric model the way that Newton’s Laws are of Einstein’s. The so-called “wrongness” is categorically different. Like Bomb’s mention of flat earth, which also isn’t a simplified version of the globe earth model. It is wrong at a foundational level. That’s not what is happening with Newton and Einstein.

What makes the wrongness of flat-earth "foundational", and why isn't the wrongness of Newton similarly "foundational"? I don't understand the distinction you're drawing. If a simplified version of the globe earth model isn't the flat earth, what is?

You get flat earth from globe earth by setting the curvature to zero;

No. You don’t. That’s not what “flat earth” is.

This is becoming too distracting a detail of this thread but before you decide what you’ve suggested here is a good line of argument, please go find out what the flat earth model is.

I'm talking about this:

Flat Earth - Wikipedia

en.wikipedia.org

What are you talking about?

 

[pood]

Yes, I agree entirely. My raising the geocentric model of Ptolemy was in response to you correctly pointing out that the flat earth model was not only “grossly contrary” to reality, but easily disprovable because it made false predictions.

Say what?!? How the bejesus do you figure a theory making false predictions implies it's easily disprovable?

How the bejeezus did you come up with the idea that I said that?

By reading what you said! You said "easily disprovable because it made false predictions"! What the heck did you mean by those words, if a theory making false predictions doesn't imply it's easily disprovable?!?

But what you read, is still not quite what I said. I didn’t say that A theory that made false predictions was easily disprovable (which is generic and implies any theory); I said a specific theory (flat earth) was easily disprovble; but, as it happens, maybe that requires a little elaboration, because I myself brought up the undetermination example with respect to a ship disappearing over the horizon. I would say that some false theories are relatively easily disprovable, compared to others; so there is that required emendation. I do think the flat earth is relatively easily disprovble,

I said just the opposite, citing the success of the Ptolemaic system for over a thousands years.

Indeed. You appear to have applied contradictory premises.

No, see above. I never said or implied that ALL false theories are easily disprovable.

However, SOME theories grossly at odds with reality are easily disprovable, the flat earth being one.

Right; but "it made false predictions" is plainly not the reason it's easily disprovable. The Ptolemaic system made false predictions but is not easily disprovable. Newtonian mechanics made false predictions but is not easily disprovable. Either QM or GR makes false predictions but is not easily disprovable. So what is it about flat earth that makes it easily disprovable?

The Greek demonstration, the relative positions of the stars in the sky, the ship and horizon thing, and I’m sure there are more, even many more. But, I realize that since I brought up undertermination, and used an example of it myself —saying you could account for the ships sinking over the horizon by keeping a flat earth and positing an unsual property of light — then, yes, your point is taken. Still, in all undetermination cases, one must assess the plausibility of the stated alternative theory. I could say, for example, that Newton’s law of gravitation is wrong, because it only operates when someone is looking. When no one is looking, things fall up, and then I could go about the laborious task of constructing a mathemtical description of such a state of affairs. But would you or anyone take that seriously as a plausible or viable alternate theory of gravity?

As you yourself point out, Iron Age sailors would have certainly known that the earth was round.

Actually, Iron Age sailors would have certainly had what they needed to figure out that the earth was round but the historical record shows it was not until very late in the Iron Age that the Greeks started to put it together. Aristotle knew the earth was round but Homer had no idea. (Moreover, Iron Age sailing wasn't confined to Greeks but the rest of the world took even longer to realize the earth was round.)

Well, some people thought it was round and some thought it was flat. No great surprise there, because most people are not scientists. Homer certainly wasn’t (though of course science as known today did not exist then). But even today, there is a flat earth society. So the fact that some people still hold to a false theory doesn’t mean that the theory isn’t relatively easily disprovable, compared to others that are more obdurate. Lots of people believe all sorts of stupid shit.

More later.

 

[Shadowy Man]

Keep in mind that Ptolemy’s geocentric model isn’t a simplified version of a heliocentric model the way that Newton’s Laws are of Einstein’s. The so-called “wrongness” is categorically different. Like Bomb’s mention of flat earth, which also isn’t a simplified version of the globe earth model. It is wrong at a foundational level. That’s not what is happening with Newton and Einstein.

What makes the wrongness of flat-earth "foundational", and why isn't the wrongness of Newton similarly "foundational"? I don't understand the distinction you're drawing. If a simplified version of the globe earth model isn't the flat earth, what is?

You get flat earth from globe earth by setting the curvature to zero;

No. You don’t. That’s not what “flat earth” is.

This is becoming too distracting a detail of this thread but before you decide what you’ve suggested here is a good line of argument, please go find out what the flat earth model is.

I'm talking about this:

Flat Earth - Wikipedia

en.wikipedia.org

What are you talking about?

I didn’t see anywhere on that page a description like “take a globe earth and set the curvature to zero”. The conception that the earth was flat wasn’t anything like what we now call a physics theory. As soon as anyone actually started thinking about the quantifiable, observable consequences of any earth geometry model, the flat earth was thrown out.

The process was not remotely like what Einstein did with Newton’s theory. If Einstein’s theory didn’t reduce to Newton’s in the non-relativistic regime he would have assumed GR was wrong.

By the time physics was invented there was no flat earth model.

I hope maybe you’ll begin to understand the distinction between the flat/globe earth relationship and the Newton/Einstein relationship.

 

[pood]

Excellent example. This is why I don't understand why you guys seem to regard the flat earth theory as foolishness on a level with Ptolemaic astronomy.

I will get back to replying to the middle stuff in your post later, but I wanted to respond to this now. My point was that I don’t regard the Ptolemaic model as foolishness; it held on for over a thousand years and that’s a lot longer that general relatvity/quantum mechanics will likely hold, since those two are at odds, which means that we are missing something and one or both theories are incomplete or wrong at some level of description. My point all along was that SOME theories are RELATIVELY easy to disprove (flat earth) compared with others that are not (geocentrism).

Although, even here, the ancient Greeks had a heliocentric model. Aristotle opposed it because of the parallax problem.

 

[Shadowy Man]

But, I realize that since I brought up undertermination, and used an example of it myself —saying you could account for the ships sinking over the horizon by keeping a flat earth and positing an unsual property of light — then, yes, your point is taken.

I wouldn’t concede the point so easily. Because no such theory has ever been put forward. Notional hypotheses are not theories. If you are able to correct me I’d be happy to see any such theory that shows how things would work with a flat earth and light that bends to make every observation appear to demonstrate a globe earth. I’ve never seen one.

 

[pood]

But, I realize that since I brought up undertermination, and used an example of it myself —saying you could account for the ships sinking over the horizon by keeping a flat earth and positing an unsual property of light — then, yes, your point is taken.

I wouldn’t concede the point so easily. Because no such theory has ever been put forward. Notional hypotheses are not theories. If you are able to correct me I’d be happy to see any such theory that shows how things would work with a flat earth and light that bends to make every observation appear to demonstrate a globe earth. I’ve never seen one.

I haven’t either, but I suggest one could devise such a theory, and perhaps make it internally consistent in such a way that it would be hard to falsify, especially in the time period we are talking about, when Iron Age sailors were about, science as we know it didn’t exist, and no one knew anything about the behavior of light. Today, of course, such a theory would be a non-starter, but back then, maybe not (though back then, too, they had no modern concept of a “theory” anyway). The whole point of theory undetermination is that there are (theoretically!) multiple ways to account for data. Ptolemy and Copernicus were two such ways to account for the same set of data. Utlimately Copernicus was vindicated because of the more refined observational techniques of empricism.

 

[Shadowy Man]

We are getting far afield here. My issue was primarily with the statement that Newton’s laws are “grossly contrary to reality”. If you want to stand by that statement then what current theory do you think is not “grossly contrary”? General relativity? Why isn’t that also “grossly contrary”?

 

[Shadowy Man]

But, I realize that since I brought up undertermination, and used an example of it myself —saying you could account for the ships sinking over the horizon by keeping a flat earth and positing an unsual property of light — then, yes, your point is taken.

I wouldn’t concede the point so easily. Because no such theory has ever been put forward. Notional hypotheses are not theories. If you are able to correct me I’d be happy to see any such theory that shows how things would work with a flat earth and light that bends to make every observation appear to demonstrate a globe earth. I’ve never seen one.

I haven’t either, but I suggest one could devise such a theory, and perhaps make it internally consistent in such a way that it would be hard to falsify, especially in the time period we are talking about, when Iron Age sailors were about, science as we know it didn’t exist, and no one knew anything about the behavior of light. Today, of course, such a theory would be a non-starter, but back then, maybe not (though back then, too, they had no modern concept of a “theory” anyway). The whole point of theory undetermination is that there are (theoretically!) multiple ways to account for data. Ptolemy and Copernicus were two such ways to account for the same set of data. Utlimately Copernicus was vindicated because of the more refined observational techniques of empricism.

Honestly, you guys can ding me for not giving much thought to those pre-physics cosmological notions. I don’t really care about them much. We might as well be arguing about how one might observationally determine the number of turtles holding up the earth.

I’ll grant you Ptolemy as there were actual quantifiable predictions that were reasonably accurate once he added enough variables to get everything to work.

And what’s this leads to, in my opinion, is that we shouldn’t get worked up too much about what “reality” is with respect to physical models to represent it. Trying to make qualifiable comparisons to physical theories (like “grossly contrary”) isn’t particularly useful to me. What matters is how much something can work and the better it works the better representation of reality it is. I will concede Bomb’s point about also having simplicity in theories. And we might consider that modern cosmology may be heading down the road of increasing epicycles with unobservable cosmological characteristics. We will see.

 

[pood]

We are getting far afield here. My issue was primarily with the statement that Newton’s laws are “grossly contrary to reality”. If you want to stand by that statement then what current theory do you think is not “grossly contrary”? General relativity? Why isn’t that also “grossly contrary”?

I take it you are addressing Bomb here. As I said, I think he is making a mountain out of a molehill out of the Newton/Einstein thing. We could say that strictly, Newton’s theory is false, superseded by relativity and QM. Or we could be much more nuanced about the matter, and dispose with talk of theories being “true“ or ”false,” and just look at whether they are useful, whether they make good predictions within their domain of applicability. As you note, relativity reduces to Newtonian physics outside the relativistic realm. So I don’t know why that bothers Bomb. Does he deny that? We can use Newton just fine to calculate the trajectories of spacecraft to other planets. However, if we want to make our GPS devices work, Newton won’t do. We have to take into account the time dilation introduced both by special relativity (relative motion) and general relativity (gravity time dilation).

 

[Shadowy Man]

I have heard it said by some laypersons, as well as (remarkably) even some scientists, that “Einstein proved Newton wrong.”

I basically take issue with the word “wrong” in that sentence and I would say that those who utter this sentence probably don’t have a good enough understanding of the physics involved to make such a comment so definitively.

 

[pood]

I don’t recall at the moment Bomb calling Newton’s theories “grossly contrary to reality,“ but if he did, maybe he’d like to at least modify that somewhat in light of the discussion.

 

[Shadowy Man]

We are getting far afield here. My issue was primarily with the statement that Newton’s laws are “grossly contrary to reality”. If you want to stand by that statement then what current theory do you think is not “grossly contrary”? General relativity? Why isn’t that also “grossly contrary”?

I take it you are addressing Bomb here. As I said, I think he is making a mountain out of a molehill out of the Newton/Einstein thing. We could say that strictly, Newton’s theory is false, superseded by relativity and QM. Or we could be much more nuanced about the matter, and dispose with talk of theories being “true“ or ”false,” and just look at whether they are useful, whether they make good predictions within their domain of applicability. As you note, relativity reduces to Newtonian physics outside the relativistic realm. So I don’t know why that bothers Bomb. Does he deny that?

Maybe it doesn’t bother him. But I still hold that the reduction of Einstein to Newton as certain parameters get small is not in the same category as the reduction of Globe earth to flat earth when certain parameters get small.

I’ve never seen flat earth suggested as the latter.

We can use Newton just fine to calculate the trajectories of spacecraft to other planets. However, if we want to make our GPS devices work, Newton won’t do. We have to take into account the time dilation introduced both by special relativity (relative motion) and general relativity (gravity time dilation).

Yes. The fuller theory is necessary to make those things work, but that doesn’t make the approximations categorically “wrong”.

 

[Shadowy Man]

I don’t recall at the moment Bomb calling Newton’s theories “grossly contrary to reality,“ but if he did, maybe he’d like to at least modify that somewhat in light of the discussion.

That’s how my involvement started. You may have to dig back a bit.

 

[Shadowy Man]

We are getting far afield here. My issue was primarily with the statement that Newton’s laws are “grossly contrary to reality”. If you want to stand by that statement then what current theory do you think is not “grossly contrary”? General relativity? Why isn’t that also “grossly contrary”?

I take it you are addressing Bomb here.

yes. I apologize for the implication by using the word “you” in my response to you.

 

[Shadowy Man]

I don’t recall at the moment Bomb calling Newton’s theories “grossly contrary to reality,“ but if he did, maybe he’d like to at least modify that somewhat in light of the discussion.

Read post #181 and the discussion leading up to it.