Starting with MIckleson-Morley in 1887, and successive experiments, it has become understood and accepted by anyone with at least a high school, or even junior high school, science class that the aether simply does not exist. And this is the science of the thing. — tim wood

Well, I myself, am very sound evidence that this statement is a blatant falsity. And why do you think that this is "the science of the thing" when it's really the pseudoscience of the thing. In reality, it's just a denial of what can logically be concluded from Michelson-Morley type experiments, and denial of the current body of evidence, in a hypocritical effort to adhere to some dogmatic stipulations.

This is unfortunate because, stripped of these connotations, it rather nicely captures the way most physicists actually think about the vacuum. . . .

The denial is like a fear of God. But good theologians have progressed far beyond this attitude of instilling fear, the conventional approach now is to cultivate the love of God. Why are scientists so primitive in their behaviour, showing outright fear of the unknown, as if they will be punished if they step off the beaten path to the slaughterhouse?

You're in a science discussion, which you are determined to derail, and your account is just that you're "doing" no science at all, but metaphysical speculation. — tim wood

This happens to be a philosophy forum, not a science forum, so the participants in any discussion are more likely to be philosophers rather than scientists. So you ought to expect that your thread would contain philosophical points of view instead of insisting that we adhere to some dogma of pseudoscience.

Typical. You're asked three questions, which you ignore. You confuse "forum" with "discussion." And of course Mickleson-Morley is "pseudoscience" and "blatantly false."

The classical notion, yes, but perhaps not quite that simple. — jgill

You're being a bit disingenuous. The Laughlin quote you provided refers to the quantum vacuum, not the luminiferous aether. Yes, the quantum vacuum is an established fact, but it is not the medium through which light was once thought to propagate.

The classical notion, yes, but perhaps not quite that simple. From Wikipedia: "...The modern concept of the vacuum of space, confirmed every day by experiment, is a relativistic ether. — jgill

The question before us, if I recall correctly, is whether light propagates absent aether. MU uses logic to prove to himself that there must be an aether, because light is a wave, waves require media, therefore the aether. And probably M&M's aether itself because he says their experiment is blatantly false and pseudoscience.

As to modern scientific understandings, agreed, never quite that simple. Here is a short article for the rest of us, easy to read:
https://bigthink.com/starts-with-a-bang/aether-exist/
The idea is that MU can have his aether - there is no evidence for it - as what he calls metaphysical speculation, and which I disqualify of substance in a scientific discussion. Or alternatively we can have angels, "Thousands at his bidding speed / And post o’er Land and Ocean without rest"; no evidence of these either. And any other fantasy anyone cares to offer.

But "metaphysical speculation" - MU hasn't told us what that is, although asked - must in any discussion of science, yield to science. That, or nonsense reigns.

A science of the undetectable is a curious thing indeed. Metaphysical.

And of course Mickleson-Morley is "pseudoscience" and "blatantly false."
10 hours ago — tim wood

Tim woods, your reading skills are as bad as T. Clark's. I didn't say "Mickleson-Morley is 'pseudoscience'". I was arguing that the conclusion, that some people draw, that Michelson-Morley type experiments have proven that there is no medium for light waves, is pseudoscience.

Typical. You're asked three questions, which you ignore. You confuse "forum" with "discussion." And of course Mickleson-Morley is "pseudoscience" and "blatantly false." — tim wood

I ignored your questions because each one of them except the last requires a very long essay, and I really do not see the relevance of the material. If you want to know what "cause" and "metaphysics" mean, try looking them up. If you want to know more precisely, my use, in a specific context, then provide the context. Otherwise I'll continue to ignore such questions as unnecessary distractions. The third question I had already answered so that's why I ignored it. Here, I'll repost.

It's fundamentally different from the aether, because the aether was always understood as an independent, separate substance from the bodies which exist within it. This was the premise of the M-M experiment. Now, respecting the results of M-M, we can either say that this was a misunderstanding of the aether, and produce a new model of the aether which does not have that requirement, or we can insist that "separate substance" is essential to the conception named "aether", and therefore dismiss "aether" as inadequate, and come up with a new word to refer to the medium for light.

Clearly, "field" is inadequate because it represents the medium with random locations, arbitrary points, instead of identifying the true particles which must exist within the medium, comprising the medium, as is required to support the observed wave motion of electromagnetism. Only through identification and modeling of the true particles of the medium can an adequate understanding of it be produced. And according to what M-M indicates (no aether wind), along with what the experiments of quantum field theory indicate, all massive objects must be composed of this same medium. — Metaphysician Undercover

If that doesn't answer your third question, let me know what is lacking.

The idea is that MU can have his aether - there is no evidence for it - as what he calls metaphysical speculation, and which I disqualify of substance in a scientific discussion. — tim wood

Have fun with your so-called "scientific discussion". I'll leave you to your pseudoscience now.

I was arguing that the conclusion, that some people draw, that Michelson-Morley type experiments have proven that there is no medium for light waves, is pseudoscience. — Metaphysician Undercover

So just to be clear, you sincerely believe that Einstein (along with the entire scientific community) misinterpreted the results of M-M and are engaging in some form of pseudoscience?

It's not obvious to me that he's disagreeing with Einstein at all. Einstein at times seems to provide quotes suggesting he himself believes in an aether of sorts - just one that's Lorentz invariant, which makes it compatible with relativity.

Here's a quote from Einstein himself:

• According to the general theory of relativity space without ether is unthinkable

So just to be clear, you sincerely believe that Einstein (along with the entire scientific community) misinterpreted the results of M-M and are engaging in some form of pseudoscience? — EricH

No, I believe that there is divided opinion in the "scientific community", and many members of it do not even form an opinion about this, because it is not necessary for their purposes. Most physics is applied physics, and the extremely speculative part is better known as metaphysics. The majority of scientists do not venture into this, "metaphysics", or make their opinions (if they have them) known. So I believe members of this forum are making unjustified generalizations (inductive conclusions) with statements like "along with the entire scientific community".

Here's something to consider Eric. Relativity theory was created for pragmatic purposes, and is fundamentally not truth-apt. Relativity gives us very useful principles for application, and modeling motions, but it cannot give us truth. When Galileo first developed modern relativity, he used it to show that both the geocentric, and heliocentric models of the motions of the sun and planets are compatible and equally valid, by the precepts of "relativity". However, most of us believe that there is a "truth" to the modeling of the solar system, and we know that to get to the truth of this matter, we need to go beyond what "relativity" provides for us.

Since relativity models movement as relative to an artificial frame of reference, rather than as relative to a background "space", the reality of the background is ignored. Simply put, since we do not know the reality of the background, we replace it with known frame of reference, which serves the purpose. The frame of reference is designed for the purpose, it is not designed to truthfully represent a "real" background.

This became a problem for relativity theory because things like light, and gravity, were considered as properties of the background. It made classical relativity theory inconsistent with the observed movement light. So Einstein proposed that if we make some stipulations about the speed of light relative to moving bodies, and the passage of time, we could establish compatibility between the movement of light, and the movement of bodies, and bring light and gravity to be consistent with relativity theory. This opened up a whole new field of usefulness for relativity theory, Einsteinian relativity.

The fundamental issue remains though, relativity theory is pragmatically oriented, and is designed to ignore the importance of truth. This is why we have physicists like Stephen Hawking proposing ontologies such as "model-dependent reality", and others with the idea that the universe is a "simulation". If we ignore this fundamental fact, that relativity is designed to be useful, but with its usefulness we sacrifice the possibility for truth, and instead we start to think that relativity theory is true, this induces the possibility of all sorts of strange ontologies to support the "reality" of relativity.

Now we have a backward approach to metaphysics. Instead of basing our metaphysics in strong principles directed toward truth, we direct or metaphysics away from truth to support relativity theory which denies the possibility of truth. So, as metaphysicians looking for truth, the proper approach is to observe and understand all features of reality, and build a consistent ontology accordingly. This means the influence of useful theories like relativity must not be given undue preference, because the goal is truth, which relativity is not directed toward.

Relativity theory was created for pragmatic purposes, and is fundamentally not truth-apt. — Metaphysician Undercover

Black holes, gravitational lensing, and gravitational waves have all been observed and were predicted on GR. What do you mean by relativity theory not being truth-apt?

I have the same question. "Not truth apt" is an interesting phrase. It's like he's not saying it's false or wrong, it's like he's saying it's not even in the category of things that can be right or wrong. Now, I certainly accept that there are things that could be described like that, but I can't see that relativity is in that group.

According to the general theory of relativity space without ether is unthinkable — flannel jesus

I used your quote to track down the article - "Ether and the Theory of Relativity" by Albert Einstein. Here's a link:

https://mathshistory.st-andrews.ac.uk/Extras/Einstein_ether/

Really great paper taken from a lecture in 1920. I've been looking for something like this for a long time.

Your quote is taken quite a bit out of context. It is clear the "ether" Einstein is talking about is space or space-time, not a luminous ether which is the supposed medium for the propagation of light. He makes that distinction explicitly.

If you want to know what "cause" and "metaphysics" mean, try looking them up. — Metaphysician Undercover

I have. Read books on them. And in refusing answer you make clear you do not know what you are talking about. And you have made completely clear in other threads that you consider learning about these things a waste of your time, because you have already decided that you know what they mean.

Relativity theory was created for pragmatic purposes, and is fundamentally not truth-apt. — Metaphysician Undercover

Since effing when has science ever been "truth-apt"? Where in any edition of the scientific method does "truth" enter in. And another question to you, what is it that you imagine "truth" to be? Because at least in this context it's clear you do not know.

Whatever is true, is true with respect to some standard that makes it true (no criteria, no true). True, then, is an after-the-fact judgment. And as an after-the-fact judgment, has nothing to do with the thing itself. Science is concerned with the things themselves, and thus "true" no part of it. After the fact, some scientists might say that such-and-such appears to be true, but what he or she means is that given certain inputs, certain outputs that are expected actually occur; or, in other words, "It is true to say."

Cause is so difficult a concept to make rigorous that for a century most of science has dispensed with its use as a meaningful term, except in informal usage where it stands as a shorthand, or in the few areas it may still be used.

Metaphysics has been defined as either the study of being, which is the study of nothing at all, because if being has any predicates it ceases to be just being. Or alternatively, as the study of the absolute presuppositions, aka hinge propositions - the understandings that undergird - of the thinking done by different people at different times. "Metaphysics" has also blown up as a term to include nonsense, a lot of it, as the "Metaphysics" shelf at the bookstore will attest.

Metaphysics, then, is either the study of nothing (no thing), or it is a science with a well-defined and determinate subject matter (finding out what people usually unconsciously hold as absolute beliefs in grounding their systems of thinking), or it is nonsense, which MU attempts to dignify with a title of "metaphysical speculation," which, he says, if he does it it is just no science at all, but also says this:

Most physics is applied physics, and the extremely speculative part is better known as metaphysics. — Metaphysician Undercover

Caveat, then, in dealing with MU: he plays by his own rules, he makes it up as he goes along, he is impervious to correction when he's wrong, and if pressed, breaks out into nonsense. This I call Trumpian, and by that I mean pathological. And a pathology, it might be added, that science has tried to close and keep closed the door on since the beginning.

I used your quote to track down the article - "Ether and the Theory of Relativity" by Albert Einstein. Here's a link:
https://mathshistory.st-andrews.ac.uk/Extras/Einstein_ether/ — T Clark

:up:
Absolutely worth the read - although keeping in mind the substance of it is more than 100 years old.

Since effing when has science ever been "truth-apt"? Where in any edition of the scientific method does "truth" enter in. And another question to you, what is it that you imagine "truth" to be? — tim wood

OK, so now we see a big difference between science and metaphysics. I would say metaphysics seeks truth, and truth means corresponding with reality. This would answer ''s question as well.

Prediction in itself is a usefulness, but usefulness is limited by the intended purpose, so prediction does not necessarily indicate truth. A person can successfully predict that the sun will rise the next day, using nothing but statistics. With even more information the person can predict the time and place that the sun will rise. All these predictions are based in assumptions of continuity, that things will continue to occur in the way that they have in the past. But these predictions, and the ability to predict, give no indication of an understanding of what is actually going on. This is obviously the case with quantum mechanics, and quantum field theory right now, there is a tremendous ability to predict, without any understanding of what is actually going on.

"Truth" implies an understanding of what is going on, which takes us beyond the ability to predict. What Galileo showed with relativity theory, is that an understanding of what is going on is not a requirement for the capacity to predict the notions of bodies. All that is required is an adequately formulated frame of reference, information from the past, and the fact that the bodies will continue to move as they have (as Newton's first law). So the motions of bodies can be equally predicted from distinct frames of reference, as Galileo showed with the geocentric and heliocentric models, and what is really going on (the truth) is completely irrelevant to the capacity to prediction.

This is why we have scientists like Stephen Hawking promoting ontologies like "model-dependent realism", within which the fundamental principle (or presupposition) is that there is no such thing as what is really going on. This is because pragmatic theories, such as relativity, dismiss "what is really going on" as unnecessary for making predictions. Then scientists turn to prediction as the sole purpose of science, neglecting a key part of the scientific process, which states that the usefulness of prediction is to be directed at verifying theories, and this clearly indicates that prediction ought not be the end in itself.

When prediction is not taken to be the end in itself, we clearly see the limitations to relativity theory, where it cannot accurately predict.

Metaphysics has been defined as either the study of being, which is the study of nothing at all, because if being has any predicates it ceases to be just being. — tim wood

Boy your logic skills are pathetic.

Cause is so difficult a concept to make rigorous that for a century most of science has dispensed with its use as a meaningful term, except in informal usage where it stands as a shorthand, or in the few areas it may still be used. — tim wood

Ok. now you admit it. Cause does not have a scientific definition. Why did you keep asking me for a scientific definition of cause, then ridicule me when I did not provide it? And if I would have provided you with a definition of "metaphysics", you would have made fun of it as well, based on what you now admit as your prejudice.

Your questioning is nothing but deception, trickery. The questions are intentional designed for one purpose only, and that is to trick someone into saying something which you can poke fun at. Your mode of discussion is simply disgusting.

OK, so now we see a big difference between science and metaphysics. I would say metaphysics seeks truth, and truth means corresponding with reality. — Metaphysician Undercover

Through speculation and with logic? And just here in the mists we make out the hard outline of MU's version of an Aristotelian science, which notwithstanding the magnitude of its achievements, is in modern terms (since at least c. 1600 AD) just no science at all. And of this ancient practice of solving problems by merely thinking about them - arguably one of very few tools available to Aristotle 2300+ years ago, and which did not always save him from absurdity - MU will not turn loose. But rather he insists on it, its methods and its conclusions. But he forgets that nature is primordial and logic and thinking are young in comparison, and thus it is logic's and thinking's task to conform to nature, and not the other way 'round. Science has ruled on the need of an aether as medium to carry light, so as much as MU really, really holds that there must be such a medium because of the logic of waves, either he must be satisfied that there isn't, or he must be dismissed. And the Einstein paper cited above from 1920 makes clear that this is no mere matter of dilettante opinion, but a complicated and multi-faceted piece of modern science.

I would say metaphysics seeks truth, and truth means corresponding with reality. — Metaphysician Undercover

We're going way off topic here, but when you use the word "truth" are referring to the Correspondence Theory of Truth?

I'll interject. There is no rigorous consistent definition of truth. My own view is that "true" - an adjective - is correctly applied in all kinds of cases. And all of those trues may be collected under the abstract noun "truth." But if you try to distill anything from truth other than that the instances are all true, you will fail. So, this is true and that is true, and each in its context is meaningful. But truth is meaningful only in a general, abstract, and non-specific way. That is, there ain't no such thing. And that is a substantial clue as to why discussions of truth are always about this theory of truth or that theory of truth and not truth itself. Doesn't mean we cannot use the concept, only that the context of the usage matters, though it may not matter in the particular discussion.

AFAICT we're basically in agreement here.

[edit] But I'm curious what MU has to say.

We're going way off topic here, but when you use the word "truth" are referring to the Correspondence Theory of Truth? — EricH

Yes, that's what I said, truth means corresponding with reality, therefore I'm using "truth" in the sense of correspondence theory.

Yes, that's what I said, truth means corresponding with reality, therefore I'm using "truth" in the sense of correspondence theory. — Metaphysician Undercover

I'm still not clear on your usage of the word truth - because I went back and am seeing this:

"Truth" implies an understanding of what is going on, which takes us beyond the ability to predict. — Metaphysician Undercover

E.g., if I say that I observed an object in a vacuum chamber accelerating towards the center of the earth at 9.8 m/sec**2, I think you would agree that that is a true statement (it corresponds with reality). But there is no understanding in that statement - it's just an observation.

Also, is there a distinction when you put the word in quotes?

E.g., if I say that I observed an object in a vacuum chamber accelerating towards the center of the earth at 9.8 m/sec**2, I think you would agree that that is a true statement (it corresponds with reality). — EricH

No I don't agree with that at all, far from it in fact. Why would I just take it for granted that this is a true statement? I would have to see your justification, your measurement technique, and how you come up with "sec**2". What does "sec**2" even mean?

Furthermore, I disagree that this is "just an observation", it is actually a very complex calculation. That something is "accelerating" requires a multitude of measurements of velocity, and each measurement of velocity requires multiple determinations of spatial-temporal location.

.

Also, is there a distinction when you put the word in quotes? — EricH

I put the word in quotes, because I was talking about the meaning of that word, which I put in quotes.

What does "sec**2" even mean? — Metaphysician Undercover

https://www.quora.com/What-does-per-second-squared-mean

That something is "accelerating" requires a multitude of measurements of velocity, and each measurement of velocity requires multiple determinations of spatial-temporal location. — Metaphysician Undercover

Assume all of that is done to your satisfaction beyond all reasonable doubt.

" **2 " means raised to the second power (i.e. squared). So " **3 " means raised to the third power, etc. This is standard scientific notation.

N.B. - I believe there is a way to do superscripts in the forum interface but I don't know how to do that.

Assume all of that is done to your satisfaction beyond all reasonable doubt. — EricH

The concept of "acceleration" involves a fundamental philosophical problem. Acceleration is the rate of increase of velocity. So if an object goes from being at rest, to moving, there is a brief period of time where its "acceleration" is necessarily infinite. This is a fundamental measurement problem, and another form of the same problem is at the heart of the uncertainty principle of quantum physics, as the uncertainty relation between time and energy in the Fourier transform.

This problem was exposed by Aristotle as the incompatibility between the concept of "being" (static) and the concept of "becoming" (active). The way that modern physics deals with this problem, through the application of calculus does not resolve the problem. It simply veils the problem by allowing the unintelligible issue, infinity, to be present within the mathematical representation.

Now, the very same philosophical problem which Newton and his contemporaries had to deal with in the relationship between bodies, becomes paramount in modern physics in its relationships of energy. The issue though, is that Newton and his contemporaries were dealing with relatively long durations of time, so the methods of calculus were adequate for covering up this problem which only increases as the period of time is shortened. Now physicists are dealing with extremely short durations of time, so the uncertainty becomes very relevant and significant. That's what the time/energy uncertainty indicates, the shorter the time period, the more uncertain any determination of energy will be.

Accordingly, using the current mathematical conventions, such calculations of acceleration will never be done "beyond all reasonable doubt", because the current convention is to allow the unintelligible (infinite) to be a part of the mathematical representation..

The concept of "acceleration" involves a fundamental philosophical problem. Acceleration is the rate of increase of velocity. So if an object goes from being at rest, to moving, there is a brief period of time where its "acceleration" is necessarily infinite. — Metaphysician Undercover

Show your math.

You're overthinking it a little bit. Regardless of philosophical issues, we can in fact experimentally verify, to some reasonable degree of precision, that bowling balls and pool balls both accelerate toward the ground when dropped. If you have philosophical problems with the concept of acceleration, you should separate that from your ability to look at that evidence and see what does, in fact, happen

there is a brief period of time where its "acceleration" is necessarily infinite. — Metaphysician Undercover

Really! And after "a brief period of time" of infinite acceleration, how fast are we going? But yours was in response to a good and fair question asked you by EricH, here:

Yes, that's what I said, truth means corresponding with reality, therefore I'm using "truth" in the sense of correspondence theory.
— Metaphysician Undercover
I'm still not clear on your usage of the word truth - because I went back and am seeing this:
"Truth" implies an understanding of what is going on, which takes us beyond the ability to predict.
— Metaphysician Undercover

E.g., if I say that I observed an object in a vacuum chamber accelerating towards the center of the earth at 9.8 m/sec**2, I think you would agree that that is a true statement (it corresponds with reality). But there is no understanding in that statement - it's just an observation. — EricH

Why don't you try answering his question?

Tim, Flannel, and Wonderer beat me to the punch here. Any statement in the form "such-and-such a person observed X at such-and-such place & time" is either true (corresponds to reality) or false (does not correspond to reality).
Remember the verb here is "observed".