Fields and ether

[quiet]

I would like to collect reasons to discard the idea of ether.

If there are reasons not to dismiss that idea, I would also like to collect that.

[Strange]

By ether, do you mean the old idea of the luminiferous ether?

if so:

1. There is no evidence for it

2. There is no need for it

3. Why resurrect a dead theory?

In our next episode: “phlogiston: why has it fallen out of favour?”

[studiot]

There is a book devoted to this

A history of theories of the Aether and electricity

E T Whittaker

There were two volumes of thos

Vol 1 from Descartes to the end of the 19th century

Vol 2 (written later) Modern theories (to about 1930).

 

You could also look at the firat 30 pages of

The Theory of Relativity

Professor C Moller

Oxford University Press.

This develops the theory of light as known in Maxwellian times, as classical wave theory and sets the requirements for ethers of various natures, developing them from Hugens onwards to determine the difference between phase and ray velocities, showing their importance and invariances.

 

He then goes on to analyse in detail  early (fizeau and foucalt) experiments ans demonstrate what these were capable of and equally importantly what they were not.

After then analysing Hoek and Fizeau's experiments

He turns to discuss Lorenz / Fitzgerald  and

Finally to Michelson whose experiments were the first capable of detecting an ether.

The mathis in this early part of the book is not difficult.

However the whole of Chapter 1 is rather too long to post as an extract.

[J.C.MacSwell]

1 hour ago, Strange said:

By ether, do you mean the old idea of the luminiferous ether?

if so:

1. There is no evidence for it

2. There is no need for it

3. Why resurrect a dead theory?

In our next episode: “phlogiston: why has it fallen out of favour?”

Indeed. Next time you are caught in the bitter cold without a sweater...futilely rubbing your hands together..you won't be so quick to shun it's existence...you'll wish you had more of it

[Strange]

10 minutes ago, J.C.MacSwell said:

Indeed. Next time you are caught in the bitter cold without a sweater...futilely rubbing your hands together..you won't be so quick to shun it's existence...you'll wish you had more of it

Or are you thinking of caloric, another out of favour idea?

While we are at it, maybe we should start s thread one why leeches and blood letting are no longer in use

[quiet]

All people have offered answers of the kind I'm looking for. I appreciate that.

Obviously, everything that can be added will complement the great historical lines. And some personal vision would be a wonderful possibility. I do not mean the word personal to expose a speculative idea. I refer that to an exhibition that invites reflection with an original didactic.

[Carrock]

6 minutes ago, Strange said:

While we are at it, maybe we should start s thread one why leeches and blood letting are no longer in use

Or maybe not.

From https://en.wikipedia.org/wiki/Hirudo_medicinalis#Today
 

Quote

Today

Medicinal leech therapy (also referred to as Hirudotherapy or Hirudin therapy) made an international comeback in the 1970s in microsurgery,^[7][8] used to stimulate circulation to salvage skin grafts and other tissue threatened by postoperative venous congestion,^[7][9] particularly in finger reattachment and reconstructive surgery of the ear, nose, lip, and eyelid.^[8][10] Other clinical applications of medicinal leech therapy include varicose veins, muscle cramps, thrombophlebitis, and osteoarthritis, among many varied conditions.

 

 

[J.C.MacSwell]

14 minutes ago, Strange said:

Or are you thinking of caloric, another out of favour idea?

While we are at it, maybe we should start s thread one why leeches and blood letting are no longer in use

I was. Thanks for the correction. +1. I need to keep better track of my science history.

OTOH, did you know that leeches have been back in use for some time?

http://sciencenetlinks.com/science-news/science-updates/modern-leeching/

OT: The luminiferous ether was assumed to be fixed to some preferred frame, but measurements of the speed of light, and in electricity and magnetism, indicated otherwise.

Edit: I see Carrock was much quicker

Edited December 14, 2018 by J.C.MacSwell

[quiet]

1 hour ago, J.C.MacSwell said:

Indeed...

 

1 hour ago, Strange said:

Or are you thinking of caloric...

 

56 minutes ago, Carrock said:

Or maybe not...

 

Dear members of the forum. Use this thread as a battlefield for a dispute? We had started well. We can continue well.

---------

Let's not transform scienceforums into teasing forums. When I ask, I do it seriously. For example. Why is ether not necessary? Then we take the theorems of vector analysis and see mutual rotors regenerating fields in successive places that configure the advance in the direction of propagation. Very happy I say that ether is unnecessary because I have mutual rotors that do the job. My happiness is an epistemological abuse of the worst. Mathematics does not physically explain why ether is unnecessary. Admit that the cause is not the ether, it implies finding something physical that operates as an underlying cause. If the lid of the pot does not jump for a demon that was locked and burned with heat, then you have to find something physical that causes the cap to jump. Mathematics describes behavior. Behavior of something? Yes. Of something that physically exists. And teasing does not diminish epistemological abuse. Do not increase it. Teasing is, at best, a resource that dilutes the axis of the thread in a gap of distraction.

Edited December 14, 2018 by quiet

[J.C.MacSwell]

Ok, quiet. Fair enough.

A reason to keep it, or rather resurrect it in a modified form, could be facilitated by extra dimensions. Credible attempts have been made earlier by Kaluza-Klein and others, and later string theorists, but nothing come up with yet has fully made sense.

[quiet]

34 minutes ago, J.C.MacSwell said:

Ok, quiet. Fair enough.

A reason to keep it, or rather resurrect it in a modified form, could be facilitated by extra dimensions. Credible attempts have been made earlier by Kaluza-Klein and others, and later string theorists, but nothing come up with yet has fully made sense.

Thank you. It's the kind of response that really works for what I need.

Kaluza and Klein added a curved fifth dimension, of limited size and small scale. In 11 dimensions, the 7 extra dimensions are all small scale?

Edited December 14, 2018 by quiet

[MigL]

IIRC Kaluza-Klein had no compactified dimensions.

Sting or M theory's 10-11 dimensions can have the additional ones compactified as Calabi-Yau manifolds ( or not ).

[Strange]

7 hours ago, quiet said:

Why is ether not necessary?

There was an initial assumption that if there were waves, there must be some sort of physical medium for those waves. That assumption turned out to be false. Another example of science winning over "common sense".

7 hours ago, quiet said:

Behavior of something? Yes. Of something that physically exists.

Basically, we have detected something that we can describe using wave equations. Does that mean that mean the waves are real or just a useful description?

"Physically exists" is a difficult concept that belongs in the philosophy forum. You could spend months arguing about the meaning of "physical" and then months more arguing about the meaning of "exists". When you have a 5 definitions of each, you then spend years arguing about which of those apply to the electromagnetic waves.

And, if you take the quantum view, there are no waves at all. Just quanta of the underlying field. Does that field exist? Yes, because we measure its effects. No, because it is just a mathematical abstraction. It is impossible to say which of these is "true". 

7 hours ago, quiet said:

And teasing does not diminish epistemological abuse.

We have new models that work. The ether model did not work. Ditto phlogiston, caloric, "plum pudding" atom, steady state universe, etc.

As these models are not consistent with the evidence, they have been replaced with new models that do. I cannot understand why so many people want to go back to models that have failed. Some of them seem to have a weird romantic attraction; a sort of "steam punk science" aesthetic. Fine. But this is a science forum, not an "aesthetics of dead theories" forum.

 

7 hours ago, J.C.MacSwell said:

Ok, quiet. Fair enough.

A reason to keep it, or rather resurrect it in a modified form, could be facilitated by extra dimensions. Credible attempts have been made earlier by Kaluza-Klein and others, and later string theorists, but nothing come up with yet has fully made sense.

I'm not really sure how that relates to the concept of a luminiferous ether as a substance that pervades space. 

Obviously, many people have later used the word "ether" to describe other things: Einstein famously described spacetime as being an "ether" (because it is everywhere) much to the delight of the steam-punk pseudoscientists. They ignore the bit where he went on to point out that it could not be a material substance (ie. is not the luminiferous ether they were looking for). Others have used to word to describe one or more of the quantum fields that pervade space, etc.

10 hours ago, quiet said:

I would like to collect reasons to discard the idea of ether.

If there are reasons not to dismiss that idea, I would also like to collect that.

This is not a science discussion. It is a history of science discussion. Maybe you should go and cast a vote in the "should there be history forum" thread.

8 hours ago, Carrock said:

Or maybe not.

From https://en.wikipedia.org/wiki/Hirudo_medicinalis#Today

I knew someone (or two people) would pick up on that. But it is important to note that the leeches are used for very different things.

Which is a good analogy for the fact that wave equations can be used to describe the movement of material substances (eg. sound waves in air) but can also describe things that are have no material existence (eg. light or electrons, etc).

Just because we use the same tool, doesn't mean we are clinging on to the old, discredited ideas of how things work.

10 hours ago, quiet said:

I would like to collect reasons to discard the idea of ether.

If there are reasons not to dismiss that idea, I would also like to collect that.

Let's turn this around.

What reasons do you have for considering the ether? If there are reasons to accept this ether, I would also like to see that.

What properties are you claiming for the ether? How is the experimental evidence consistent with those properties? What other experiments do you need?

 

[J.C.MacSwell]

1 hour ago, Strange said:

I'm not really sure how that relates to the concept of a luminiferous ether as a substance that pervades space. 

Nor is anyone else.

1 hour ago, Strange said:

Let's turn this around.

What reasons do you have for considering the ether? If there are reasons to accept this ether, I would also like to see that.

What properties are you claiming for the ether? How is the experimental evidence consistent with those properties? What other experiments do you need?

 

First of all, as already discussed, the luminiferous ether as per the concept as we know it is inconsistent with our measurements. We know it doesn't work.

I think an argument for considering "something" is that we have come to agree on a physical model where a photon leaving the Sun arrives some 8 minutes later, the exact time varying in an exact way, very accurately and consistent with our model. So what is it about this distance that doesn't allow the photon to arrive in 6 minutes? Or 6 years?

We don't know what it is about the photon that does the accounting for this consistency, or anything about the space between the Sun and the Earth that would allow for such consistency either. We really don't know if there is something actually needed to do this accounting or not, we just know if there is it is not the type of mechanism we have yet imagined.

[quiet]

@strange, your last post have the class of content that really work for me. Thank you. +1

Only one question. Have I wrote in any paragraph something tending to restablish the idea of ether? Agree respect to place this thread in history section.

[Strange]

26 minutes ago, J.C.MacSwell said:

First of all, as already discussed, the luminiferous ether as per the concept as we know it is inconsistent with our measurements. We know it doesn't work.

Which is why I asked the OP to clarify. I get the impression that is exactly what he is talking about.

27 minutes ago, J.C.MacSwell said:

I think an argument for considering "something" is that we have come to agree on a physical model where a photon leaving the Sun arrives some 8 minutes later, the exact time varying in an exact way, very accurately and consistent with our model. So what is it about this distance that doesn't allow the photon to arrive in 6 minutes? Or 6 years?

We have models that work. We have had attempts at models that haven't worked. We will (probably) have better models. That doesn't seem to be what the OP is talking about. Even if someone did decide to apply the label "ether" to some of those models. 

1 minute ago, quiet said:

Only one question. Have I wrote in any paragraph something tending to restablish the idea of ether?

I don't know. I was trying to understand your motivation.

Was it just about the history of science and how one particular theory came to be rejected? Or was it a plea to resurrect that theory? (We get a very large number of people who wish to do the latter and I have very little patience with it. I'm sorry if that made my responses appear abrupt!)

[Carrock]

2 hours ago, Strange said:

I knew someone (or two people) would pick up on that. But it is important to note that the leeches are used for very different things.

In the bad old days leeches were used very unscientifically for letting choleric or stagnant blood etc, with Robin Hood allegedly the most famous victim of this quack treatment.

Nowadays they're used to scientifically exsanguinate people because it's better than alternative treatments.

 https://en.wikipedia.org/wiki/Hirudo_medicinalis#Today

Quote

The therapeutic effect is not from the small amount of blood taken in the meal, but from the continued and steady bleeding from the wound left after the leech has detached, as well as the anesthetizing, anti-inflammatory, and vasodilating properties of the secreted leech saliva.

 

It's perhaps significant that the only recipe, for a stye treatment, in the 10th century Bald’s Leechbook that has been tested and found as effective as modern treatments had nothing to do with leeches.

From https://www.nottingham.ac.uk/news/pressreleases/2015/march/ancientbiotics---a-medieval-remedy-for-modern-day-superbugs.aspx

Quote

The remedy was tested on cultures of the commonly found and hard to treat bacteria, Staphylococcus aureus, in both synthetic wounds and in infected wounds in mice.

The team made artificial wound infections by growing bacteria in plugs of collagen and then exposed them to each of the individual ingredients, or the full recipe. None of the individual ingredients alone had any measurable effect, but when combined according to the recipe the Staphylococcus populations were almost totally obliterated: about one bacterial cell in a thousand survived.

The team then went on to see what happened if they diluted the eye salve – as it is hard to know just how much of the medicine bacteria would be exposed to when applied to a real infection. They found that when the medicine is too dilute to kill Staphylococcus aureus, it interfered with bacterial cell-cell communication (quorum sensing). This is a key finding, because bacteria have to talk to each other to switch on the genes that allow them to damage infected tissues. Many microbiologists think that blocking this behaviour could be an alternative way of treating infection.....

 

 

But we were absolutely blown away by just how effective the combination of ingredients was.  We tested it in difficult conditions too; we let our artificial ‘infections’ grow into dense, mature populations called ‘biofilms’, where the individual cells bunch together and make a sticky coating that makes it hard for antibiotics to reach them.  But unlike many modern antibiotics, Bald’s eye salve has the power to breach these defences.”

Dr Steve Diggle added: “When we built this recipe in the lab I didn't really expect it to actually do anything. When we found that it could actually disrupt and kill cells in S. aureus biofilms, I was genuinely amazed. Biofilms are naturally antibiotic resistant and difficult to treat so this was a great result. The fact that it works on an organism that it was apparently designed to treat (an infection of a stye in the eye) suggests that people were doing carefully planned experiments long before the scientific method was developed.”

"It's not off topic if a mod introduces it."

[Strange]

54 minutes ago, Carrock said:

"It's not off topic if a mod introduces it."

The Richard Nixon defence. I might have to report myself...

[quiet]

This thread come and go between good contribtions and fighting words that no thing contribute.

I am greatful with the the contributive attitude, wich is evident in many posts.

If someone want to continue fighting, go freely to that. I am not interested in that.

Best regards.

Edited December 14, 2018 by quiet

[Strange]

1 minute ago, quiet said:

This thread come and go between good contribtions and fighting words that no thing contribute.

I am greatful with the the contributive attitude, wich is evident in many posts.

If someone want to continue fighting, go freely to that. I am not interested in that.

Best regards.
 

Perhaps you could clarify what you are asking (the luminiferous ether or something else) and why?

[quiet]

@strange

The reasons that lead the 19th siecle physycists to finally reject the idea of ether are in the pertinent bibliography. Were not correct to say, more than 150 years later, "oh, very fool the 19th siecle people, because there is a lot of reasons and a lot of evidences respect to the foolishness of that idea". This make no sense. What make sense is a comparison between the set of reasons we have today to reject it, and the sets of reasons in 19 siecle, one set to agree with the idea of ether, other set to reject it. And, within those primitive context, to recognize how and why the wright ideas go step by step emerging and achieving more and more consensus.

Edited December 14, 2018 by quiet

[studiot]

34 minutes ago, quiet said:

@strange

The reasons that lead the 19th siecle physycists to finally reject the idea of ether are in the pertinent bibliography. Were not correct to say, more than 150 years later, "oh, very fool the 19th siecle people, because there is a lot of reasons and a lot of evidences respect to the foolishness of that idea". This make no sense. What make sense is a comparison between the set of reasons we have today to reject it, and the sets of reasons in 19 siecle, one set to agree with the idea of ether, other set to reject it. And, within those primitive context, to recognize how and why the wright ideas go step by step emerging and achieving more and more consensus.

 

But the 19 century scientists didn't just accept or reject an aether.

They calculated consequences according to their best Science and then proposed tests, which they carried out to the best of their ability.

A real shining example of progress via the scientific method.

Furthermore they knew the limits of their abiltiy.

They knew that the experiments of Fizeau were against calculations carried out by neglecting higher order terms in series and so were first order.

They were only able to measure the effects of higher order terms at the very end of the century.

It was these later experiments that confirmed the lack of aether and lead to a search for other explanations.

 

By the way, siecle is the French word for century.

Edited December 14, 2018 by studiot

[Strange]

42 minutes ago, quiet said:

What make sense is a comparison between the set of reasons we have today to reject it, and the sets of reasons in 19 siecle, one set to agree with the idea of ether, other set to reject it.

The evidence against the ether now is largely the same as it was in the 19th century. All attempts to have measure the effects of any ether model have failed.   We have developed alternative models, such as the invariance of the speed of light, which are consistent with the evidence.

Some, if not all ether models, imply Lorentz violation. Noether's theorem tells us that if there were Lorentz violation then we would see different effects if the same measurements were made at different places.  Many other types of experiments have been developed to test this, again they are all consistent with the view there is no ether.

So, on the one side we have zero evidence for the ether (and no need for it, apart from "common sense" which is equivalent to no reason at all) and large quantities against it. 

48 minutes ago, quiet said:

And, within those primitive context, to recognize how and why the wright ideas go step by step emerging and achieving more and more consensus.

It is a reasonably good example of how evidence and science can show that common sense is wrong.

But I think there are many better examples of how science progresses. For example, phlogiston was a good theory that matched the evidence available. So it was, for a while, a scientific theory (unlike ether). But then, as more evidence became available, it was clear a new model was required and it was replaced.

However, these are both examples of ideas (one unsupported and one a good theory) that were completely overturned. That is actually fairly unusual in science. Most theories are just incrementally adjusted and improved as more information becomes available. And often,  even when there is a better model, the old one continues to be useful (eg. Newtonian gravity). Which is partly why modern science is not considered to be about discovering "truth" or "reality".

[quiet]

@strange
@studiot
Thanks for your contributions. This is the kind of reflections that I expected.

Language issue: Thanks studiot for help me (more than once). Century! OK. Haha... French! May be excess of de Broglie's books?

[studiot]

3 hours ago, Strange said:

For example, phlogiston was a good theory that matched the evidence available.

Phlogiston was never a 'good' theory.

The evidence against it had already been obtained and confirmed by others for nearly 100 years before the word phlogiston was invented.

The'theory' required the additiona proposition (theory with no experimental backup) of negative weight to support it.

 

https://eic.rsc.org/feature/the-logic-of-phlogiston/2000126.article

Edited December 14, 2018 by studiot