Gravity waves and the aether

[Mike Smith Cosmos]

With every example you've given of a medium for waves, there are independent ways of detecting and interacting with the medium, other than a wave in them.

Why can't we do that for EM and gravity?

Well I assume that interaction is usually by either Resonance or impact with sufficient energy . I am not totally clear what you are asking?

Presumably we can do that with electro-magnetism and gravity? I have only been considering 'Waves ' , because of the title of the thread ( " Gravity waves and the Aether " ) . I have been a bit sensitive of keeping on target ! I can wander a bit sometimes !

 

Mike

Mike, the very theory which predicts and forms the basis for gravitational waves has not needed an aether or medium for the past century.

I find it rich that you can now claim that the gravitational waves are proof of an aether or medium.

If it wasn't for mediumless relativity, no-one would have even been looking for gravitational waves.

 

Its been 30 pages now and I bet Moontanman regrets the OP.

Its getting tiresome, especially since you're not presenting supporting facts or mechanisms.

Wishing and hoping don't count for much

I am sorry if the subject of Medium/ Aether are tiresome , I personally have found resonance in a different medium than the originating waves 'host ' of energy , one of the most fascinating scientific phenomenon of all my time and life. From the first sight of a germanium crystal, to the i-phone, and i- pad not 6inches from my fingertips . This phenomenon , of Electro-magnetic transmission and reception has been my life's continuing fascination and endeavour to fully understand , and now with Gravity waves and Aether , quite WHAT IS GOING ON ?

 

I still find it quite incredible that for so little energy , we can communicate across the globe , and space. Incredible , mind blowing . Yet we still seem to differ as to our understanding of ( medium or no-medium / Aether ) . And this equally seems to apply to gravity and its waves , yet in a different way ( and medium / aether ) .

 

And as regards your comment " has not needed an aether or medium for the past century."

All I can retort is " maybe someone took a wrong turn , somewhere , sometime " !

 

To me , it will be on my gravestone " He never did find out definitely " ( " I told them I was ill ! " )

 

Mike

Edited August 2, 2016 by Mike Smith Cosmos

[ajb]

And as regards your comment " has not needed an aether or medium for the past century."

All I can retort is " maybe someone took a wrong turn , somewhere , sometime " !

 

All attempts at an aether or mechanical theory of gravity have so far failed to reproduce the phenomenology we see. With the advent of general relativity - which has been tested to some huge degree of accuracy - the general general thinking is that all such models will fail.

 

Moreover, we now think that the basic fundamental things in nature are fields. This is supported by the sucsess of general relativity and electromagnetic theory, but also the standard model. Going to a mechanical model seems a great step back.

[Mike Smith Cosmos]

All attempts at an aether or mechanical theory of gravity have so far failed to reproduce the phenomenology we see. With the advent of general relativity - which has been tested to some huge degree of accuracy - the general general thinking is that all such models will fail.Moreover, we now think that the basic fundamental things in nature are fields. This is supported by the sucsess of general relativity and electromagnetic theory, but also the standard model. Going to a mechanical model seems a great step back.

Yes I can follow that about FIELDS and do understand it in principle . BUT , the hang up I have , is that I cannot see fields just , hanging there across the whole Universe , from one side to the other , without a medium / Aether for the field to hang on or be supported by , or exist , IN ,ON, or ABOUT. The field would surely collapse if there was no supportive structure in ' SOMETHING ' with substance ? Surely .?

 

Mike

Edited August 2, 2016 by Mike Smith Cosmos

[ajb]

BUT , the hang up I have , is that I cannot see fields just , hanging there across the whole Universe , from one side to the other , without a medium / Aether for the field to hang on or be supported by , or exist , IN ,ON, or ABOUT. The field would surely collapse if there was no supportive structure in ' SOMETHING ' with substance ? Surely .?

This statement and question show that you don't understand fields.

 

Why would a field collapse? And what do you mean by collapse?

Edited August 2, 2016 by ajb

[Mike Smith Cosmos]

This statement and question show that you don't understand fields.Why would a field collapse? And what do you mean by collapse?

Well surely an electric field can exist between two poles say . Clouds and earth . And if the field is too large you get a collapse, and lightning discharges between the poles.

 

Or you have point charges distributed evenly over a three dimensional space . Fine an electric field exists over all this space . But then what ever is holding or making up the point charges , constitutes a medium for ELECTRO MAGNITISM as AETHER surely .

 

Similarly for mass , two masses apart , gravity force between them . Or Matter in a whole host of particles, making up distributed mass across the whole of space . Thus making up a medium or AETHER for GRAVITY . and it's WAVES

 

Or am I up a ' gum tree '

 

Mike

[swansont]

Well I assume that interaction is usually by either Resonance or impact with sufficient energy . I am not totally clear what you are asking?

Presumably we can do that with electro-magnetism and gravity? I have only been considering 'Waves ' , because of the title of the thread ( " Gravity waves and the Aether " ) . I have been a bit sensitive of keeping on target ! I can wander a bit sometimes !

 

 

 

You need to consider more if you want to present evidence of an aether. I can detect water without seeing a water wave. Same with air, rock, whatever. There is independent evidence of the existence of these things, and solid evidence that the waves are in that medium. So, since there is no solid evidence of EM or gravitational waves being in anything, what is the independent evidence of an aether?

[ajb]

Well surely an electric field can exist between two poles say .

Yes, electric charges act as sources of the electromagnetic field.

 

And if the field is too large you get a collapse, and lightning discharges between the poles.

You get electrical breakdown of the air (or whatever is in between the charges or charged objects) and a current flows.

 

 

Fine an elBut then what ever is holding or making up the point charges , constitutes a medium for ELECTRO MAGNITISM as AETHER surely .

No - charge particles act as souces and sinks of the electromagnetic field. But that are not any kind of aether.

 

We can see that light travels across vacuum - in the lab or across space - without the need for charged particles along the way.

 

Similarly for mass , two masses apart , gravity force between them . Or Matter in a whole host of particles, making up distributed mass across the whole of space . Thus making up a medium or AETHER for GRAVITY . and it's WAVES

Like EM, this does not seem to be the case - objects with very little matter in between then interact gravitationally okay.

 

Or am I up a ' gum tree '

You seem to be mixing the notion of sources with some mechanical aether.

[Mike Smith Cosmos]

Yes, electric charges act as sources of the electromagnetic field.You get electrical breakdown of the air (or whatever is in between the charges or charged objects) and a current flows.No - charge particles act as souces and sinks of the electromagnetic field. But that are not any kind of aether.We can see that light travels across vacuum - in the lab or across space - without the need for charged particles along the way.Like EM, this does not seem to be the case - objects with very little matter in between then interact gravitationally okay.You seem to be mixing the notion of sources with some mechanical aether.

.

I have had a good long talk with a colleague , a Physics Doctorate , who by no means agreed with me on many points , and in some way endorsed what you have said , to some extent . But it has clarified something about my terminology , and your terminology . About these matters . To some extent it seems it might be a matter of terminology. What I am calling medium , might be more like well distributed very small matter and isolated charge . This producing a distributed electro magnetic field , which I am calling a medium .

 

Similarly with denser concentrations of matter , and gravitational fields , he is saying I might be referring to this distribution of matter and gravitational fields , as medium / aether , which might be , being viewed by the larger scientific community as just location and distribution of matter , where I am referring to it as a medium / aether .

 

I am not sure I know the difference ?

 

Mike

Edited August 2, 2016 by Mike Smith Cosmos

[swansont]

The medium would be the thing that is waving.

[ajb]

This does sound like sources rather than a mechanical medium - so where 'field lines start and end'.

 

What is true is that accelerated charges create ripples in the electromagnetic field - but again we don't think of the charges as a medium.

Edited August 2, 2016 by ajb

[Strange]

The medium would be the thing that is waving.

 

Whereas, the "distribution of matter" (small or large) is what gets waved (by the changes in space-time).

[disarray]

 

Whereas, the "distribution of matter" (small or large) is what gets waved (by the changes in space-time).

 

It seems that there is some agreement that the "distribution of matter" or (electromagnetic) charges provides its own diffuse field in which waves are propagated,

 

I think that the term "aether" has anti-relativity theory connotations in terms, for example, of positing absolute frames of reference, spatial or otherwise, and that therefore the term should not be used unless one is actually trying to prove the antiquated concept in its original sense.

 

Perhaps there is an instinctive/intuitive tendency to think of space/time itself as being a medium since not only do some waves 'require' a medium, but also because we think of spacetime as existing in its own right, given that it does seem to have properties/qualities (rather than being nothing at all and having no properties) such as the ability to fluctuate (e.g., time dilation) and to expand, and therefore we think of spacetime being some sort of medium in which waves might also exist.

 

To the extent that we can isolate spacetime from every other thing we know about in the universe, it seems to have unique properties....or perhaps it does not exist at all per se, but is really just the mathematically describable playing field in which events take place.

 

Given that t ("time") is just an abstract symbol, is it just mathematical/linguistic convention for one to speak of time (spacetime) as slowing down (e.g., with respect to variations in gravitation/acceleration) or is it more 'accurate' to suggest that 'things' themselves just slow down (e.g., molecular velocity) in certain situations (e.g., in a hypothetical rocket going near the speed of light or objects getting closer to a large massive body such as a planet)?

 

That is, since neither space nor time (spacetime) seem to have, unlike water, any perceptible 'material'/mechanical properties, it seems to me that, backed into a semantic corner, one might suggest that we can only logically say that the movement of things themselves (however explicably or inexplicably) just slow down (e.g., metabolic rate) in certain situations, rather making the "empty" (apart from its abstract mathematical content) statement that timespace dilates.

 

In a nutshell: Does relativity describe the way "things" slow down, or the way spacetime slows down, or can we just not say one way or the other, since these two ways of looking at what relativity describes seems, for all practical purposes, to be identical.

Edited August 2, 2016 by disarray

[Strange]

It seems that there is some agreement that the "distribution of matter" or (electromagnetic) charges provides its own diffuse field in which waves are propagated,

 

 

Be careful, here. The matter that is distributed in space (whether gases in the intergalactic medium or the arms of the LIGO detector) are perturbed by the presence of gravitational waves. But they are not necessary, as a medium, for the propagation of those waves.

 

I think that the term "aether" has anti-relativity theory connotations in terms, for example, of positing absolute frames of reference, spatial or otherwise, and that therefore the term should not be used unless one is actually trying to prove the antiquated concept in its original sense.

Agreed. Many people (including very respectable scientists) have used the term as a metaphor to describe something that pervades the universe - space-time, dark energy, electromagnetic fields, etc. But this can just lead to confusion when people associate it with the classical aether. It is best avoided altogether.

[disarray]

Be careful, here. The matter that is distributed in space (whether gases in the intergalactic medium or the arms of the LIGO detector) are perturbed by the presence of gravitational waves. But they are not necessary, as a medium, for the propagation of those waves.

 

I take your point, particularly given, for example, the fact that photons and presumably gravitational waves can 'travel' in a vacuum.

 

The thought that the fields/influence of electrons and photons and perhaps gravity are so extensive and diffuse that they provides their own field for propagating their respective waves is tempting, particularly when some physicists talk about electrons being connected or rather being able to exchange information at opposite ends of the universe, as if the reach or arm of their fields is so long that their presence is all pervasive.

 

The idea that velocity or acceleration/gravity (equivalence principle) not only seems to make things slow down, but actually makes them slow down physically (e.g., metabolic rates of the proverbial rocket ship inhabitants), owing to the fact that the speed of light is limited, is a hard one to grasp. Given the equivalence between gravity and velocity (or acceleration?) in terms of time dilation, a layperson such as myself might wonder why there are not waves associated with (changes in) velocity just as there are waves associated with gravitation.

 

(I do like speculation, but also, I am making efforts to understand the math, e.g., have set up an accurate and working formulas in Excel for determining time dilation that matches the results that one gets with an online applet. Just having trouble grasping how the fact that the speed of light is constant makes the formulas get the results that they do.)

 

Edited August 2, 2016 by disarray

[Mike Smith Cosmos]

Be careful, here. The matter that is distributed in space (whether gases in the intergalactic medium or the arms of the LIGO detector) are perturbed by the presence of gravitational waves. But they are not necessary, as a medium, for the propagation of those waves.

 

 

Agreed. Many people (including very respectable scientists) have used the term as a metaphor to describe something that pervades the universe - space-time, dark energy, electromagnetic fields, etc. But this can just lead to confusion when people associate it with the classical aether. It is best avoided altogether.

.

How do we know that " The matter that is distributed in space (whether gases in the intergalactic medium or the arms of the LIGO detector) are perturbed by the presence of gravitational waves. But they are not necessary, as a medium, for the propagation of those waves. "

 

How do we know that is so . ? We would have to remove all that stuff to the last molecule of intergalactic space . And the material part of the LIGO detector . Then wait for a potential gravity wave , and test as to whether it arrived or did not arrive , to prove or disprove what you are saying , surely ?

 

Mike

 

P.s.

 

Would the ' P ' wave and 'S' wave arrive through the Earths mantle to shake a building to bits , half way across the world , if there was a great vacuum gap somewhere deep in the earth mantle , in the path of the propagating earthquake 'P' and 'S' waves ?

 

 

Edited August 2, 2016 by Mike Smith Cosmos

[Strange]

How do we know that " The matter that is distributed in space (whether gases in the intergalactic medium or the arms of the LIGO detector) are perturbed by the presence of gravitational waves. But they are not necessary, as a medium, for the propagation of those waves. "

 

How do we know that is so . We would have to remove all that stuff to the last molecule of intergalactic space . Then wait for a potential gravity wave , and test as to whether it arrived or did not arrive , to prove or disprove what you are saying , surely ?

 

Mike

 

 

 

 

Because we have a theory that does not use any of that stuff as a medium. The theory works exceedingly well, even predicting the gravitational waves that were recently detected.

 

You are, of course, welcome to come up with an equally detailed and accurate theory that does include that material as a medium of transmission. Taking into account, for example, the hugely varying composition, density, temperature and velocity of that medium in different places and how that would affect the force of gravity and the transmission of gravitational waves (or, more to the point, why these things don't have any effect).

 

But after 6 weeks, 31 pages and 615 posts with zero progress towards that, I don't imagine it is ever going to happen. You will continue stumbling around in your closed-minded and unimaginative approach ("but I like my old ideas; why should I consider anything new that someone more creative than me came up with").

[Mike Smith Cosmos]

Because we have a theory that does not use any of that stuff as a medium. The theory works exceedingly well, even predicting the gravitational waves that were recently detected.

 

).

.

 

I do not get it . The test is made with ALL this stuff in place . And it works . But the test has not been tried out without the medium , presumably because it would be impossible to remove , " all of distributed matter in space , between the two colliding black holes , and Everthing in its path up to the final detector " , to see if it still arrived without the medium ?

 

Is it falsifiable ? I am ducking , please do not hit me !

 

Mike

 

Ps . You are probably right , and I am probably wrong . But ' as sure as eggs ' , when I next go to sea to sail across to ' where ever ' , I am getting in a REAL boat and floating on a REAL medium SEA and setting off on a 1000 mile journey . Happy that I am going to arrive at my destination PORT .

 

You can launch yourself , down a slipway , when the tide is fully out, and hope to goodness you do NOT need the ocean to get anywhere , ( because it is not needed- tee hee) across the 1000 miles of rocky , slimy sea bed , with all sorts of nasties on the way ! Best of Luck , I hope you float across in ' thin air ' .

 

Just a story !

Edited August 2, 2016 by Mike Smith Cosmos

[disarray]

.

I do not get it . The test is made with ALL this stuff in place . And it works . But the test has not been tried out without the medium , presumably because it would be impossible to remove , " all of distributed matter in space , between the two colliding black holes , and Everthing in its path up to the final detector " , to see if it still arrived without the medium ?

 

Trying to tag along here. Is the question now whether gravitational waves can operate without a medium, e.g., in a perfect vacuum with all of distributed matter in space, etc., removed?

If so,here is an excerpt from a icts physics lecture if the math is relevant::

Propagation of gravitational waves in vacuum

In vacuum, the wave equation becomes hαβ = 0; the solution is a superposition of plane waves traveling at the speed of light: hαβ(x) = ReZ d3~ k (2π)3 Aαβ(~ k)eikµxµ (11)
2 where kµ = (ω,~ k) and ω =qδij~ ki~ kj........

https://webcache.goo...n&ct=clnk&gl=us

In any case, it seems that gravity is not even a force, but rather variable curvature of space that results in the expansion of space, so we should not expect to interpret gravitational waves as being like mechanical waves connected with some force.

Edited August 3, 2016 by disarray

[Mike Smith Cosmos]

 

Trying to tag along here. Is the question now whether gravitational waves can operate without a medium, e.g., in a perfect vacuum with all of distributed matter in space, etc., removed?

If so,here is an excerpt from a icts physics lecture if the math is relevant::Propagation of gravitational waves in vacuum

In vacuum, the wave equation becomes hαβ = 0; the solution is a superposition of plane waves traveling at the speed of light: hαβ(x) = ReZ d3~ k (2π)3 Aαβ(~ k)eikµxµ (11)

2 where kµ = (ω,~ k) and ω =qδij~ ki~ kj........

https://webcache.goo...n&ct=clnk&gl=us

In any case, it seems that gravity is not even a force, but rather variable curvature of space that results in the expansion of space, so we should not expect to interpret gravitational waves as being like mechanical waves connected with some force.

.

Very good perception of the situation , but it's very easy to sidestep from reality to a mathematical life raft, without even noticing the change.

 

I equally find myself in this situation. :-

 

When having a fairly intensive discussion yesterday , face to face with a Doctorate Physics colleague. In desperation I started to use arguments such as " but my intuition , tells me " this just is not right " . ( in desperation that I was loosing ground in the discussion) His remark to this was , as he is also a pilot , if you are flying and you start to loose height drastically , NATURAL , INTUITION, would be to lift the nose of the aircraft UP , in order to ' drive ' the aircraft upwards. QUITE THE OPPOSITE is required, counter intuitively , you need to put the aircraft nose DOWN so as to pick up 'air speed' , to prevent the aircraft stalling , and hence crashing .

 

However , I notice that MIRROR MATTER :- https://en.m.wikipedia.org/wiki/Mirror_matter

 

Uses the word ' mediate ' in its discussion of potential candidates for Dark Matter . There appears to be a whole ' Raft ' of particles ,( pardon the pun ) , that can act as a medium , possibly in existence , that are currently being investigated and actually found . So I am not convinced yet , that the idea of MEDIUM , AETHER for GRAVITATIONAL WAVES is necessarily lost .?

 

Mike

Edited August 3, 2016 by Mike Smith Cosmos

[Strange]

.

 

I do not get it . The test is made with ALL this stuff in place . And it works . But the test has not been tried out without the medium , presumably because it would be impossible to remove , " all of distributed matter in space , between the two colliding black holes , and Everthing in its path up to the final detector " , to see if it still arrived without the medium ?

 

 

That is not how science works.

 

If you can show that the "stuff" will have a measurable effect, THEN we can do an experiment to test your idea. As it is, all you have are empty, meaningless claims.

 

As it is, the theory without using the stuff works fine. Therefore the stuff is not part of the theory. If it were missing from the theory as you suggest, then the theory would not work.

.

Very good perception of the situation , but it's very easy to sidestep from reality to a mathematical life raft, without even noticing the change.

 

The maths is simply a description of reality, not something separate from it.

 

 

 

Uses the word ' mediate ' in its discussion of potential candidates for Dark Matter .

 

It uses the word mediate in reference to bosons. Bosons are the particles that mediate forces.

 

If gravity can be quantised then the (hypothetical) particle that mediates gravity would be the graviton.

 

BUT ... these virtual particles that mediate forces are not a medium. It is not even clear that they exist. They are just a mathematical tool for solving problems.

[Mike Smith Cosmos]

That is not how science works.

 

If you can show that the "stuff" will have a measurable effect, THEN we can do an experiment to test your idea. As it is, all you have are empty, meaningless claims.

 

As it is, the theory without using the stuff works fine. Therefore the stuff is not part of the theory. If it were missing from the theory as you suggest, then the theory would not work.

 

The maths is simply a description of reality, not something separate from it.

 

 

 

It uses the word mediate in reference to bosons. Bosons are the particles that mediate forces.

 

If gravity can be quantised then the (hypothetical) particle that mediates gravity would be the graviton.

 

BUT ... these virtual particles that mediate forces are not a medium. It is not even clear that they exist. They are just a mathematical tool for solving problems.

Yes , but I always was told ( much as I personally hate the expression , and idea.) That according to " Popper " . A theory is only valid in science " if it is falsifiable " . And I can not see a way that the LIGO experiment is falsifiable , as you would have to remove all the 'stuff ' between out there billions of miles away to the LIGO project detector to test for false. Which is not possible ? Unless I have got the " popper " thing wrong ( which I personally do not like anyway )

 

Mike

[Strange]

Yes , but I always was told ( much as I personally hate the expression , and idea.) That according to " Popper " . A theory is only valid in science " if it is falsifiable " .

 

 

And GR is falsifiable. That is why all the tests have been done: to try and falsify it.

 

 

 

And I can not see a way that the LIGO experiment is falsifiable , as you would have to remove all the 'stuff ' between out there billions of miles away to the LIGO project detector to test for false.

 

Theories are falsified, not experiments.

 

The theory (which does not mention a medium) says "gravity behave like this".

Experiments test whether gravity does behave like that. (If it didn't the theory would be falsified.)

It does. Therefore the theory with no medium is accurate.

 

Now, if you want to demonstrate that your hypothesis about the necessity for a medium is correct, then you need to produce an equally accurate mathematical model that DOES include the medium and show what results it produces.

Your hypothesis can then be tested (i.e. is falsifiable).

 

As it is, your vague opinions are not falsifiable and therefore not science.

[Mike Smith Cosmos]

And GR is falsifiable. That is why all the tests have been done: to try and falsify it.

 

 

 

Theories are falsified, not experiments.

 

The theory (which does not mention a medium) says "gravity behave like this".

Experiments test whether gravity does behave like that. (If it didn't the theory would be falsified.)

It does. Therefore the theory with no medium is accurate.

 

Now, if you want to demonstrate that your hypothesis about the necessity for a medium is correct, then you need to produce an equally accurate mathematical model that DOES include the medium and show what results it produces.

Your hypothesis can then be tested (i.e. is falsifiable).

 

As it is, your vague opinions are not falsifiable and therefore not science.

I know it would be nice for the mathematicians , for the model to be in maths. But I am not sure if science demands the model to be maths or nothing at all. That limits it to only mathematicians to take part.

 

Cannot I come up wth a visual model , or a mechanical model, or a miniaturised scale model, with things ( made of grit in a bag ) flapping and loose cloths acting as a medium? Is there a strict requirement , it ' HAS ' to be maths . If I make the grit in a bag precise and the cloth of the right texture? Where it works with the cloth medium , but does not work with no cloth medium. (A ) a wave develops B ) it's just a bag of grit , flapping up and down , but does not go anywhere?

 

Mike

 

 

.

[Strange]

The requirement is that your model makes testable predictions. I guess it could be a scale model or an analogue, rather than mathematical. But your model would have to be accurate enough to be testable against what we measure. That is a challenge but not impossible. The effects of binary black holes are determined by simulating a model, rather than by pure mathematical trickery (because the mathematics is too complex).

 

For example, you might say "gravitational waves from a pair of black holes behave like the ripples in a pond caused by two sticks stirring". Well, they don't so that model is wrong.

 

Go ahead, show us how gravitational waves would behave in the changing density of material in space. How they travel differently between galaxies than within them, how they are affected by suns and planets, etc.

 

When you have done that, we can compare your predictions with experiment.

[Mike Smith Cosmos]

The requirement is that your model makes testable predictions. I guess it could be a scale model or an analogue, rather than mathematical. But your model would have to be accurate enough to be testable against what we measure. That is a challenge but not impossible. The effects of binary black holes are determined by simulating a model, rather than by pure mathematical trickery (because the mathematics is too complex).

 

For example, you might say "gravitational waves from a pair of black holes behave like the ripples in a pond caused by two sticks stirring". Well, they don't so that model is wrong.

 

Go ahead, show us how gravitational waves would behave in the changing density of material in space. How they travel differently between galaxies than within them, how they are affected by suns and planets, etc.

 

When you have done that, we can compare your predictions with experiment.

Just a quick thumb nail sketch to be thinking about it !

 

 

Mike