Are [gravitational] waves traveling through some form of ' Fermion ' grid ?

[swansont]

I can make thus an EM WAVE move across space to another antenna.

 

Tell me how I can manipulate space and time so I can send a gravity wave a short distance ? And detect it a short distance away ?

 

 

You can't do it. The gravitational effect is many orders of magnitude weaker than EM effect.

 

The sun is 2e30 kg, and the black holes that merged were tens of solar masses, with several solar masses being converted into the energy carried away by the gravitational waves we barely detected — movement of what, 10^-18 m? You can't scale down the detector without losing sensitivity. To have a smaller amount of energy means you have to be closer with the same detector. The radiation drops off as 1/r.

 

Converting even a kg of mass to energy is a huge amount — bigger than atomic bomb scale stuff (the Hiroshima bomb converted less than a gram), and that's more than 30 orders of magnitude smaller, meaning being 30 orders of magnitude closer gives you the same result on the detector.

 

 

(edit: a light year is about 10^16 meters, and the source was more than a billion LY away, so 10^25 meters. But we need to be 30 orders of magnitude closer from the explosion. IOW, 10 microns away from a blast a thousand times bigger than nuclear bomb.)

 

So you can't have what you want.

[Mike Smith Cosmos]

Perhaps you'll be happier - along with many others, probably - when scientists have a working model, with a quantum description, where phenomena are mediated by virtual particles, like gravitons.

I think you are spot on there . And , as my comments to Strange , I have just made , illustrate . There is probably some interesting ideas around the subject of Gravity , that are just around the corner. Exciting really .

 

Mike

You can't do it. The gravitational effect is many orders of magnitude weaker than EM effect.

 

The sun is 2e30 kg, and the black holes that merged were tens of solar masses, with several solar masses being converted into the energy carried away by the gravitational waves we barely detected movement of what, 10^-18 m? You can't scale down the detector without losing sensitivity. To have a smaller amount of energy means you have to be closer with the same detector. The radiation drops off as 1/r.

 

Converting even a kg of mass to energy is a huge amount bigger than atomic bomb scale stuff (the Hiroshima bomb converted less than a gram), and that's more than 30 orders of magnitude smaller, meaning being 30 orders of magnitude closer gives you the same result on the detector.

 

So you can't have what you want.

 

.

Oh well ! That squashed that idea . I was getting all excited there , for the moment .

 

Are you sure there are no bench experiments that can be done , with a big chunk of lateral thinking ?

And maybe a big chunk of stone or a lead block ( 1 meter x 1 meter x 1 meter )

swinging from an Oak tree lower branch?

 

 

Mike

Edited March 1, 2016 by Mike Smith Cosmos

[Mordred]

No at the individual particle level the effects of gravity is well beyond our ability to quantize. This is the underlying problem that quantum gravity faces.

 

We can only measure gravity at sufficient mass levels to have any measurable effects.

 

Unfortunately bosons being the heaviest of the standard model particles( total energy/mass not rest mass itself). Means they also take the higher energy levels to create.

 

This is particularly troublesome for the graviton. The mass expectations would require energy levels far beyond our particle accelerators.

We would actually have a better chance creating all the supersymmetric particles predicted by SUSY, than a graviton.

(Though we have good predictions that the graviton would need to be spin 2)

 

A good field of study on the graviton is geometrodynamics. Which is the QFT branch dealing specifically with gravity (though it specifically tries to model spacetime without the graviton ,originally lol)

 

http://www.google.ca/url?sa=t&source=web&cd=2&rct=j&q=geometrodynamics&ved=0ahUKEwj54MfwrZ7LAhUE-mMKHSGUBxoQFggfMAE&url=http%3A%2F%2Farxiv.org%2Fpdf%2Fgrqc%2F0409123&usg=AFQjCNHpAx0QWeJxPddqyC0p1PsHCYJeSQ

Edited March 1, 2016 by Mordred

[Mike Smith Cosmos]

(Though we have good predictions that the graviton would need to be spin 2)

A good field of study on the graviton is geometrodynamics. Which is the QFT branch dealing specifically with gravity (though it specifically tries to model spacetime without the graviton ,originally lol)

http://www.google.ca/url?sa=t&source=web&cd=2&rct=j&q=geometrodynamics&ved=0ahUKEwj54MfwrZ7LAhUE-mMKHSGUBxoQFggfMAE&url=http%3A%2F%2Farxiv.org%2Fpdf%2Fgrqc%2F0409123&usg=AFQjCNHpAx0QWeJxPddqyC0p1PsHCYJeSQ

Is this a simple lab experiment or a group project . I found it a bit of a difficult read . ( not your statement ,but the Avix article .

 

Mike

Edited March 1, 2016 by Mike Smith Cosmos

[Mordred]

It's a thesis paper on geometrodynamics covering numerous metrics since Wheeler first started modelling gravity by the action formulism.

 

Which in its simplest terms means according to its momentum influence. Loop quantum gravity follows similar metrics of action.

 

One thing to realize is you can create a successful model simply by its influence not necessarily the mechanism (particle to particle energy exchange).

 

For example spacetime geodesics uses the principle of least action.

 

https://en.m.wikipedia.org/wiki/Principle_of_least_action

 

The Hamilton's principle follows from langrenes (metrics used in the above principle.

 

https://en.m.wikipedia.org/wiki/Hamilton%27s_principle

 

These metrics don't require particle to particle exchange and neither does relativity. The reason being is your measuring the influence it has on what you can measure. Ie the standard model multiparticle system.

 

 

To put this into perspective. This paper calculates the detection requirements for a graviton. At a reasonable detection rate you would need a detector the mass of Jupiter near a primordial blackhole as the emitter.

 

http://www.google.ca/url?sa=t&source=web&cd=2&rct=j&q=graviton%20pdf&ved=0ahUKEwjfk9KRvZ7LAhVFymMKHW3hDyMQFggfMAE&url=http%3A%2F%2Farxiv.org%2Fpdf%2Fgr-qc%2F0601043&usg=AFQjCNG-bFQ_8lCsID-bXmAceGsHTeX1Fg

 

good luck doing that in an Earth bound lab lol

[Mike Smith Cosmos]

..........

 

It's a thesis paper on geometrodynamics covering numerous metrics since Wheeler .....

One thing to realize is you can create a successful model simply by its influence not necessarily the mechanism (particle to particle ....

The Hamilton's principle follows from langrenes (metrics used in the above principle.....

 

To put this into perspective. This paper calculates the detection requirements for a graviton. At a reasonable detection rate you would need a detector the mass of Jupiter near a primordial blackhole as the emitter.

......

good luck doing that in an Earth bound lab lol

.

 

That presumably is , why this new space bound project LIGO 2 a million Kms across is for . as per science news .

 

 

Mike

Edited March 1, 2016 by Mike Smith Cosmos

[Strange]

Then I would say , are you really certain you know what you are picking up , or receiving , if it's never been done before ?

 

There is a process called "science" where people develop "theories" based on what we observer. These theories use mathematics to make predictions that can be tested by experiment. Sometimes the experiment shows those predictions to be wrong and we need a better theory. Sometimes, as with gravitational waves, the experiment matches the prediction fantastically well.

 

It might have been a twenty ton truck that fell off a cliff a county distance away . And they have got the timing screwed up .

 

For one thing, a truck falling off a cliff would not reproduce the precise signal created by two black holes of a specific size merging.

 

For another, perhaps you should read about how LIGO works and the many different measures they have taken to eliminate signals like this. For one thing they do things reduce the effect on the instrument (such as having a 40 kg mirror suspended by glass fibres). Then they measure other signals and subtract them - they have many other detectors outside LIGO which will detect any local effects so they can be eliminated from the experimental results.

 

But you are asking me to believe in something that can not be checked experimentally .

 

Except it has been. I am sad to hear you say this. The argument that "you can't do it in the lab so it isn't real" is usually used by anti-science types such as creationists and those who don't like in the big bang theory.

 

There are a great many things we can't reproduce in the lab: from plate tectonics to stars. That doesn't mean we can't do experiments.

Perhaps you'll be happier - along with many others, probably - when scientists have a working model, with a quantum description, where phenomena are mediated by virtual particles, like gravitons.

 

Personally, I find it much harder to build a mental model of that concept. I don't have any "intuitive" idea of how virtual particles mediate forces. Whereas the changing geometry of space-time is kind-of obvious (perhaps because it has been around, and talked about, for longer than I have been alive).

Are you sure there are no bench experiments that can be done , with a big chunk of lateral thinking ?

And maybe a big chunk of stone or a lead block ( 1 meter x 1 meter x 1 meter )

swinging from an Oak tree lower branch?

 

swansont has just calculated the scales involved but you think you can compare this with a lead lump swinging on a rock. I wonder if you think about what people write.

[StringJunky]

 

...Personally, I find it much harder to build a mental model of that concept. I don't have any "intuitive" idea of how virtual particles mediate forces. Whereas the changing geometry of space-time is kind-of obvious (perhaps because it has been around, and talked about, for longer than I have been alive)..

Bit by bit, over the last few years, the more it makes sense. The hardest thing has been to realise that many fundaental things in the universe are not material. Actually, I think now, it's unrealistic to expect to equate macro objects with fundamental ones. The analogy I came up with, in the difficulty of researching these things, Is imagining an opaque box with hand holes and then having to describe the properties of an object that's inside by tactile means alone. You can describe as data, no more and no less, what the touch signals tell you. Everything else is storytelling what you make from it... that's your model.

Edited March 1, 2016 by StringJunky

[swansont]

Are you sure there are no bench experiments that can be done , with a big chunk of lateral thinking ?

And maybe a big chunk of stone or a lead block ( 1 meter x 1 meter x 1 meter )

swinging from an Oak tree lower branch?

 

 

Can you calculate how much gravitational radiation it would emit?

[Mike Smith Cosmos]

Can you calculate how much gravitational radiation it would emit?

Well there would be two measurements . ( at least )

Firstly the gravitational attraction at near pass at say distance R at 3 cm ( 0.03 meters ) a safe swing by . Then secondly at say 2 meters .

 

 

Using formula Force of attraction F = G m1 m2 / R squared . Where G is the gravitational constant . m1 is the mass of the probe . Say ( 0.5 Kgm ) , m2 is the mass of the 1m x1mx1m Lead or Concrete Cube ( say 200 kgms ) .

G the gravitational constant is.

( 6.67408 × 10 to the -11 m cubed kg-1 s-2

 

Or . ( 6.674 x 10 to the-11 Nm squared. /. ( kg x. seconds squared . )

 

F peak 1 = (. ? ) Newtons

 

F. min 2 =. (. ? ) Newtons ...... Calculator needed .

 

This should be an oscillating wave .

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

I have had a good chat with a mature colleague this morning . It would appear that there is some ambiguity as regards what exactly is the nature of ( space - time ) . It does appear it is GRAVITY. Itself .

Now whether gravity is in fact a field in itself having qualities of particles and fields resulting in waves seems to be up for debate.

Some feel that string theory has a place , others gravitons , other wave - practical duality. Others Gravity itself. Space - Time , itself being , GRAVITY . With all its distortions , wells and waves?

 

As near as I personally can feel good about things . Is yes there is something there , there appears to be a gravitational field about all of Space time . There are waves and disturbances present in this gravitational field . Whether these can be interpreted as particles like Gravitons ? I think I will wait and see if they can detect ' a graviton ' . But according to the information and citations from MORDRED it will require a detector the size of Jupiter and a source for the gravitons , a black hole ? To prove or disprove their existence .

 

Now what I am not sure of is ? Is the gravity ( possibly composed of Bosonic fields or fermionic particles of the correct spin to identify them as the relevant ' item '

 

Mike

Edited March 1, 2016 by Mike Smith Cosmos

[swansont]

Well there would be two measurements . ( at least )

Firstly the gravitational attraction at near pass at say distance R at 3 cm ( 0.03 meters ) a safe swing by . Then secondly at say 2 meters .

 

 

Using formula Force of attraction F = G m1 m2 / R squared . Where G is the gravitational constant . m1 is the mass of the probe . Say ( 0.5 Kgm ) , m2 is the mass of the 1m x1mx1m Lead or Concrete Cube ( say 200 kgms ) .

G the gravitational constant is.

( 6.67408 × 10 to the -11 m cubed kg-1 s-2

 

Or . ( 6.674 x 10 to the-11 Nm squared. /. ( kg x. seconds squared . )

 

F peak 1 = (. ? ) Newtons

 

F. min 2 =. (. ? ) Newtons ...... Calculator needed .

 

This should be an oscillating wave .

 

 

 

Well, no.

 

Janus has a calculation for loss of gravitational energy from orbiting bodies

http://www.scienceforums.net/topic/93568-robittybobs-law-orbital-issue/?p=908932

 

If you run the numbers, the earth orbiting the sun emits about a kW of gravitational radiation.

 

You don't seem to be appreciating how small of an effect is involved.

[Mike Smith Cosmos]

 

 

There are a great many things we can't reproduce in the lab: from plate tectonics to stars. That doesn't mean we can't do experiments.

 

Personally, I find it much harder to build a mental model of that concept. I don't have any "intuitive" idea of how virtual particles mediate forces. Whereas the changing geometry of space-time is kind-of obvious (perhaps because it has been around, and talked about, for longer than I have been alive).

 

.

?

.

I must say , I do respect what you have been saying . If I have not made my gratitude manifest , I must apologise . I do look forward to your comments and encouragement. I joust with you , in order to ' hone ' my ideas . You have been , and I hope you will continue to be a sounding board for the ' as you say exciting area of discovery , namely Gravity . I too feel that way , even if I have not shown it to you.

I ask you to bear with me in this matter and thank you for the help so far . As also Swansont's , MORDRED, , string junkie , and others

 

 

I have struggled badly with this Gravity Field , I feel slightly better at the moment ,

- thinking of ' space - time ' as being actual Gravity Itself . rather than nothing .

It's only a name , but it has connotations of 'something ' rather than 'nothing ' . To me , now there is something to influence , distort , wave about , alter , rather than just a measurement and a moment in time ( this to ' me ' does not sound as of enough substance ,. ) how gravitons fit in this remains to be seen !

 

Mike

Edited March 1, 2016 by Mike Smith Cosmos

[ajb]

- thinking of ' space - time ' as being actual Gravity Itself .

It is probability best to think of gravity not as space-time, but as the field that describes the local geometry.

 

I don't want to get to technical with you, that won't help much. But by thinking of the geometry as something 'on top of' or something 'additional' to just space and time you can start to think a bit more like you do with electromagnetism.

 

The electromagnetic field is a connection in a U(1)-principal bundle over space-time. The field strength tensor or Faraday tensor is the curvature of that connection.

 

In general relativity, we have the Levi-Civita connection, which we can understand as a connection in the frame bundle of the space-time. The Riemann curvature tensor is the curvature of the said connection. Now, the Levi-Civita connection is canonically associated with a metric, and so in the standard formalism of general relativity we can use either the metric or the Levi-Civita connection.

 

What I am trying to say, is that if you have no real problems about thinking of the electromagnetic field, then once you find the right language, thinking of gravity as the local geometry should also not be a problem.

Edited March 1, 2016 by ajb

[Mike Smith Cosmos]

It is probability best to think of gravity not as space-time, but as the field that describes the local geometry.I don't want to get to technical with you, that won't help much. But by thinking of the geometry as something 'on top of' or something 'additional' to just space and time you can start to think a bit more like you do with electromagnetism.The electromagnetic field is a connection in a U(1)-principal bundle over space-time. The field strength tensor or Faraday tensor is the curvature of that connection.In general relativity, we have the Levi-Civita connection, which we can understand as a connection in the frame bundle of the space-time. The Riemann curvature tensor is the curvature of the said connection. Now, the Levi-Civita connection is canonically associated with a metric, and so in the standard formalism of general relativity we can use either the metric or the Levi-Civita connection.What I am trying to say, is that if you have no real problems about thinking of the electromagnetic field, then once you find the right language, thinking of gravity as the local geometry should also not be a problem.

I am not sure That I have the same depth of mathematical nomenclature as you have AJB let alone the mathematical skills . Remember I come from half a century ago . I think as far as I got was complex variables, matrices , Laplace and Fourier transforms . And radiation diagrams . You say words sometimes that scare me. Maybe they are just things I know by other names.

 

I wish a description of space-time and gravity would tie me down to something tangible . Even if they have complicated names , they must describe things that people can understand otherwise we would could not recognise it , surely .

 

Speaking in terms of plans, or maps , or diagrams ,or other patterns , all these things are not the ' real thing ' . Even if the real thing is not like anything we have ever seen in our entire life, we should be able to describe it , in terms of things we do know ! Surely .

 

 

Mike

Edited March 1, 2016 by Mike Smith Cosmos

[StringJunky]

...I wish a description of space-time and gravity would tie me down to something tangible . Even if they have complicated names , they must describe things that people can understand otherwise we would could not recognise it , surely .

 

Speaking in terms of plans, or maps , or diagrams ,or other patterns , all these things are not the ' real thing ' . Even if the real thing is not like anything we have ever seen in our entire life, we should be able to describe it , in terms of things we do know ! Surely .

 

 

Mike

Make things as simple as possible, but not simpler. - A. Einstein.

 

If the mountain won't come to Mohammed, Mohammed must go to the mountain.

Edited March 1, 2016 by StringJunky

[Mike Smith Cosmos]

There is that great big area out there , that is as vaste as the whole universe , and I am lost for words to describe the very nature of it !

 

That is ridiculous, I am 72 years old , and I have not a clue what space time is made up of !

 

Mike

[StringJunky]

There is that great big area out there , that is as vaste as the whole universe , and I am lost for words to describe the very nature of it !

 

That is ridiculous, I am 72 years old , and I have not a clue what space time is made up of !

 

Mike

If you deconstruct anything you will end up at a point which, ultimately, is axiomatic. Spacetime is one of those things, I think, where you you can 'diassemble' it to space and time and that's it. They are fundamental. What is time? It's what clocks measure. Note the lack of description of time itself in that definition.

Edited March 1, 2016 by StringJunky

[Mike Smith Cosmos]

If you deconstruct anything you will end up at a point which, ultimately, is axiomatic. Spacetime is one of those things, I think, where you you can 'diassemble' it to space and time and that's it. They are fundamental. What is time? It's what clocks measure. Note the lack of description of time itself in that definition.

I think the missing ' stuff' is Einsteins Cosmological Constant ?

 

Mike

[StringJunky]

I think the missing ' stuff' is Einsteins Cosmological Constant ?

 

Mike

I don't think so. To repeat myself, when one is talking about objects in fundamental physics one runs out of definitions very quickly; they are what they are. Imagine that houses were made of fundamental particles i.e. can't be broken down any further, called "Bricks". You might be asked: "What is a house made of?". You answer: "Bricks". Them: "But what are bricks made of?" You: "Bricks". The same goes for non-massive phenomena.

Edited March 2, 2016 by StringJunky

[Mike Smith Cosmos]

Yes. O.k.

But I checked it out this morning . I went to the canal and heaved in a disturbance . What did I get " a wave "

My conclusion was " it would not have done that without a " medium " . Namely the water.

 

No matter how often I did it . The waves ALLWAYS went the same speed . Conclusion . The medium determines the speed.of the wave .

 

All this sounds very familiar . ,

 

 

Mike

Edited March 2, 2016 by Mike Smith Cosmos

[Strange]

The "medium" is space and time itself. I do wonder (and I really don't know) if some parameter(s) in the Einstein Field Equations can be interpreted as something analogous to "stiffness" or "density", or something else that would define the speed at which waves travel. Similar to how the vacuum permittivity and permeability define the speed of light.

[ajb]

I went to the canal and heaved in a disturbance . What did I get " a wave "

My conclusion was " it would not have done that without a " medium " . Namely the water.

Now think about electromagnetic waves. What medium do they require? What are they ripples in?

 

 

The "medium" is space and time itself. I do wonder (and I really don't know) if some parameter(s) in the Einstein Field Equations can be interpreted as something analogous to "stiffness" or "density", or something else that would define the speed at which waves travel. Similar to how the vacuum permittivity and permeability define the speed of light.

Up to Newton's constant, the speed of light and some pi's Einstein's curvature tensor is equal to the energy-momentum tensor of the matter/field content. So I guess you can try to interpret the components of Einstein's curvature tensor in this way. I have never thought deeply on it.

 

Edited March 2, 2016 by ajb

[Mike Smith Cosmos]

Now think about electromagnetic waves. What medium do they require? What are they ripples in?

Yes, but this is the gist of this thread question.

 

Could it not be that there are two sections of Atomic activity . Bosons orientated and Fermion orientated.

 

Those dealing with fields , waves like electro magnetism and energy transfer .

And those dealing with mass , gravity , matter and energy storage , mechanical forces.

 

And I was suggesting that the one on the side of gravity and mass was Primarily a Fermion , forces medium ?

 

 

Notice these waves take their input of energy into the medium , not from a single disturbance , but by a continuous of wind on the surface , the waves form and travel uni- direction , along the. Canal . As indeed what happens at sea. Continuous high winds blow on the oceans , and waves star to form . These dissipate their energy On arrival at an edge of the ocean these waves, dissipate their energy . What a model , full of meaning .

 

Mike

Edited March 2, 2016 by Mike Smith Cosmos

[ajb]

Mike, sometimes you seem quite poetic, but on those occasions I have no idea what you are asking! This is one of those occasions.

[Strange]

Could it not be that there are two sections of Atomic activity . Bosons orientated and Fermion orientated.

 

Those dealing with fields , waves like electro magnetism and energy transfer .

And those dealing with mass , gravity , matter and energy storage , mechanical forces.

 

And I was suggesting that the one on the side of gravity and mass was Primarily a Fermion , forces medium ?

 

The thing is, if you are talking about waves, then you are really talking about the classical view of electromagnetic radiation (and gravitational waves). In which case, bosons and fermions are irrelevant.

 

On the other hand, if you want to talk about the quantum nature (which we don't yet know how to do for gravity) then bosons are the force carriers for electromagnetism as well as gravity.

 

In either case, electromagnetic waves and/or forces propagate through the medium of the electromagnetic field (and the corresponding boson, the photon). And gravitational waves and/or forces propagate through the medium of the space-time field (and the corresponding boson, the graviton). Fermions don't come into it.