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a reply to: mbkennel

the electrical system is important to some degree. But it only really can work with what it's getting from the instrument sound wise.

For instance. There are passive electronic basses. They just have magnetic pickups that will detect the string vibrating and send that signal along to the tone controls and pan pots or whatever.

Then there are active basses usually using a single 9 volt battery to power the pickups. This more powerful pickup with the active electronics only will grab more detail from the tone the instrument naturally presents.

If the instrument puts out crappy tone or is on the lower end (usually under $1000.00) and hasn't had that much attention to woods and hardware like the bridge or nut you will actually hurt your sound to have active pickups. It's too sensitive and the whole world is gunna hear that your bass sucks.

So to actually improve the sound of a cheaper bass you go with passive electronics. (generally) But if attention to detail has been done and the instrument is of fine quality then you will want the active systems as they will pickup more details in the vibration of the string.

My bass has a 16 volt system with so much overhead that it's pre amp can send a signal too powerful to the actual amp and so I usually turn down the gain a bit when playing her.

Also the placement of the pickup in relation to the bridge is critical. The closer to the bridge the more upper midrange harmonics and frequencies the closer to the neck the more rounder of a sound with lower frequencies heard. Various bass styles P-Bass, Jazz Bass, Soapbar etc are based around the pickup placements.... Mine uses two soapbars built by Bartolini. one near the bridge and one near the neck. You have a pan to control blending of the pickups volumes and tones. Then I have onboard the bass, a Treble, Midrange and bass volume knobs. midrange frequency pan, outgoing volume knob so 5 knobs and a midrange toggle and that's before the signal even goes out the output jack.

Other things effect tone too like neck through designs. Where the neck is built straight through the body of the instrument and connected via glue. They allow more of the fundamental frequencies of the strings to resonate but they can get too muddy. Bolt on necks have a punchier sound due to the way the fundamental frequencies often don't make it through the connection to the body of the instrument so the vibes change a bit ( a good deal actually) Bolt on is more popular with most players. Me included. But if you are playing a ballad or something you might want to go with a neck through design.

Speaking of connections. The bodies of the instruments can be one single piece of wood and have a simple tone or built of many pieces of wood laminated together with glue. They exhibit more complex blends of how the fundamental vibrations interact with the instrument and the total tone outcome. My bass for instance has Alvadore wood (a soft light wood from the amazon) on it's back side composing 60 percent of the body. It tends to roll off the treble a bit and give the high end a softer sound. The face of the body is Burled heavily knotted quilted maple. It's pretty flexible since it's somewhere in the middle density wise. It gives the instrument more tonal versatility making it a good bass for session work where you never know what sorta tone they want you to have. But those two woods don't just jive so there is a laminate of Wenge wood ( a very dense African wood ) in between the two to help the vibrations pass better from one piece of wood to the other. I use Hard rock maple for the neck again for tonal versatility but also because it's strong and a six string bass tuned up has about 271 lbs of tension on the neck. The fretboard material is important too. Some basses have graphite fretboards others use soft woods. I like and use Ebony. It's very hard and dense and has a fast response to the vibrations of the strings when they connect to the fret.

A good luthier has to know all about this and has to consider all of this when constructing a bass or any instrument with his clients.

Stradivarious built his violins only using trees cut down in high alpine altitudes because they grow slower and are much denser. He just liked how that denser wood effected the vibrations of the strings.

hell even the core of what a string is SHAPED like Round versus hexagonal makes a big difference in tone. I prefer hexagonal cores with round wound wires coiled around it for the best tone in my opinion.

a reply to: BASSPLYR

Up loaded a pair of pics of my bass (and bassplyr) for reference in regards to soapbar pickups and the different woods and laminate etc. Damn I was young in these photos. But same bass I play today.

Doing some slapping and funk.




Fiddling with my knobs.

a reply to: BASSPLYR
Thanks for the explanation. I don't know much about bass guitar tonal qualities except from what I appreciate as a listener, but I never gave much thought to how those different tonal qualities were achieved before this thread, and your insights are helpful. I did know about the tone controls which are part of the pickup circuit but I didn't know about active versus passive pickups, etc.

a reply to: mbkennel
Thanks for the informative reply which is better than what I would have written even though the question was a reply to me. I hope ImaFungi learns something from it instead of dismissing it out of hand because it doesn't conform to his "ultimate logic".

originally posted by: mbkennel


Have you looked through the textbooks and videos I suggested before?

It looks like a point charge (radial electric field) plus a point dipole on the magnetic field.

Textbook drawings of magnetic field lines, is the closest pictorial representation of what this complex and mysterious and fundamental essential and substantial energetic medium appears as and exists as objectively? You know I am familiar with a point and lines extending away from it drawn in the sand, this can not give you an accurate comprehension as to how reality exists and appears to itself, objectively. This is a crude belittlement.

I don't know what you mean by intrinsically vibrating. Since an electron has no internal structure it's not clear what that would mean.

Intrinsic means; belonging to a thing by its very nature. I never said an electron has an internal structure, I suppose I expressed that from my knowledge it would appear that an electron cannot naturally (perhaps not even otherwise) stand truly still. A particulate of matter standing truly still is defined as absolute 0. If an electron were to exist in free space, and we could not define it as equaling absolute 0, then it would be moving? So a free electron plopped motionless in space by our hypothetical and theoretical god hands, would intrinsically not exist at absolute 0, there fore what would be its cause of motion? This is where the cluster muck begins, in physics, though the result of which is it beginning all over the place, scaffoldings of misunderstandings used to fasten illusions together, because now you will need to resort to other sketchy theory to explain why the electron would not stand exactly still, something about the entire universe expanding, or fluctuating quantum foam being the reason that the electron will not stand still, so the electron will not be intrinsically vibrating, but it will unavoidably vibrating due to the nature of flux of its surroundings?

"Once you choose the substance you wish to use, imagine that substance traveling towards the lone electron, planck length by planck length, and keep note of how the substance itself is attached the EM field, and how the EM field appears surrounding it, as it approaches our electron. " - me

Are you talking about a different particle and not a photon?

I brought up 'substance', because I realized talking about this topic, that ultimately what would be the source of the movement of a lone test electron; would be EM radiation...but you need to start with a 'substance' which causes EM radiation to exist, to get EM radiation. So the only times in which I mention substance or other particle, is as a means of EM radiation creator, the em radiation of which, will ultimately be responsible for moving/interacting with our test electron.

There are 3 things to focus on. An electron. I suppose we can just say, another electron. The EM field.

One electron is sitting in free space.

One electron is in our god hand.

The EM field is attached to everything.

Prior to the movement of anything, is the EM field 'still'? Or is it constantly waving and throbbing?

We take the electron in our hand and bowl it towards the still electron.

In the course of that action how does the EM field (the em field is 3d/4d right and you must never forget this right or else your 2d and 1d simplicities may not relate to reality right?) respond to the electron that was in our hand, that is now traveling away from our hand? Does it look like a bullet traveling through water? Is there just a moment of initial 'EM radiation creation' (an expanding sphere of wave, or circle?) when we accelerate the electron in our hand to bowl it? And then once it is on its way, there is no more EM radiation creation in relation to its coupling with the EM field and velocity in relation to it?

So now we have an objectively moving electron headed towards an objectively non moving electron (dont bring up relativity, in this example we are gods and have ultimate reference frames and have agreed that the test electron can be relatively still, not absolute k, but being aware of all the fluctuations which cause the electron to move one way and or another, we deduce those fluctuations, they all cancel out to equal the electron intrinsically not moving)(but those fluctuations will ruin our experiment right because they will cause the creation of EM radiation)

So the electron that was in our hand is headed towards the test electron. Does the EM radiation that initially was created when we accelerated it, hit the test electron? Lets say it does, but we are not concerned with that, because the test electron is still in its general vicinity, and our hand electron is still heading right for it. But since the hand electrons em radiation moved the test electron, this caused the test electron to emit em radiation, does this alter our hand electron...and then back and forth forever?

All I really want is to understand what the EM field is, how it exists, and how it is attached to electron, and how it reacts when electron is moved, and how it moves electron. I want it expressed in substantial terms, because lines dont exist, the lines must represent something, what do they represent. A pure fundamental substantial energy essence which cannot be created or destroyed but formulated into this very sturdy and secure system which can exist stabley across mega distances of space retaining its structure and reacting at a very high pace? This is what you represent with measly lines, which you then have the audacity to trick yourselves and others into thinking they dont even exist, and dont represent anything. Because you cant conceive of what the fundamental substantial essence is like of the fields, how this energetic medium network can exist and be stable and connected, because you cant attempt to think and conceive and work towards knowing these things, you cognitively dissonancely forced yourself to believe that it is of nothingness, of no important, of no concern. That you thinking in terms of 1ds and lines will do.

Which is why you cant answer; When a relatively still electron is moved (first, should we agree that there are 2 means by which an electron is moved; By the EM field (which you dont consider material, so I have to invent that there are 2 separate means by which an electron is moved, when really there is only 1; movement is caused by substance that is moving), and by substance, substance represented by another electron.

When a relatively still electron is moved, by electron itself or by EM radiation itself; can you conceive or draw using crude expressions and examples, can you perceive in your mind what occurs, how the EM field is attached the the electron, how the incoming EM radiation interacts with the electrons local EM field and/or the electrons body itself, and how this action, results, in the existence of more EM radiation? If you imagine an electron to be a 1d or 2d point or whatever, when you imagine it being moved, what degrees of terms do you think in when imagining the directions in which EM radiation would propagate away from the point of electron acceleration?

If an electron was traveling across this screen from left to right:

--------------------------------->

And an electron and or EM radiation was traveling from the bottom of the screen up.

a reply to: mbkennel

(continuation)

Electron traveling across the screen (lets try to imagine this in a 3d space, 4d yes including time)

------------------>


An electron and/or EM radiation is traveling from the bottom of the screen up and will intercept the Electron (if the result would be different or possible in regards to electron or EM radiation in examples, then i suppose i would seek the answer as to how they would be different, or if they would be possible to occur, perhaps only ever EM radiation can interact with electrons, but yes there is minutia there/here, with electrons cant touch so ultimately it will only be their EM fields interacting in the example of the electron, and in the example of the EM radiation traveling from the bottom of the screen upwards yeah that is the one example I am curious about, but I am also curious about the electron traveling from the bottom of the screen upwards, if after its initial creation of em radiation, if it is still traveling towards the test electron, if it is constantly creating EM radiation just by traveling, and I know that is a bit of an unknown or untouchable that has been debated in physics whether or not a constant velocity charge particle creates EM radiation constantly, so maybe there are two answers based on the possibility it does and doesnt)...anyway...



Considering this simple expression in 3d, this is still all very simple stuff, all of it is simple, i can understand anything and everything that exists because anything that ever exists will be made of material/substance which is why and how law exists, they exist hand in hand, and it is logic and reason, cause and effect. Yes the tricky part is speed and time, it is difficult to comprehend things where a million changes occur in a second, but if all the complexity and differences are pooled into their hierarchies and relationships and relatabilities, then literal sense can be made from the literal sense and order that exists.

So anyway...

The electron traveling across the screen -------------------------->


The electron and or em radiation traveling from the bottom up to intercept the electron at some point along the screen.

This is a 2d representation, but it shouldnt be difficult if you know reality therefore know what you are talking about, to extrapolate the reality of such this interaction which takes place in 3d.

The electron and/or em radiation traveling from the bottom of the screen towards the electron traveling across the street.

When the electron and or EM radiation gets close enough to the electron traveling across the street, to effect it. Using the screen as directional reference, in what directions is EM radiation propagated, from this event of an electron being accelerated. As, this is the purest example of what ever occurs when an electron is accelerated and EM radiation is produced. Because relative to the electron and ultimate objectivity, from a relative state of motionlessness, it can only be accelerated in a generalized finite amount of ways, and from a certain reference point its always the same, from a state of relative non movement to a state of motion this event predominately takes place in the values of velocity of incoming energy, and the direction does not entirely matter, unless you want to talk about the nature of spin, and perhaps depending on which side of the (I just looked up a bit the nature of degrees of sphere, but you dont think electron is a sphere anyway, even to discuss for most accurate convenience, so whatevs) electron EM radiation hits it it will react differently due to the nature of spin, and possibly nature of dipole.


So, using the terms of the screen, for starters, lets focus on just 2d, and then if you are feeling confident you can just write in the 3d answer in your reply aswell, but for 2d, the event I described, If i set up a detector on the right hand side of the screen, on the left, on the top, and on the bottom, and in all 4 corners, where would the EM radiation *solely* (important for this distinction, as i am mainly concerned with the nature of em radiation stemming from a single charged particle) created by ---------> this electrons coupling and accelerated motion, be detected?

a reply to: ImaFungi

You can't have a motionless em field an electric fields is a vector. Meaning it has to move and can't seT still unlike a scalar quantity. Vector quatities will always be in motion. So to answer your question we can't have a charge sitting anywhere the universe won't allow it. But let's look at an electrical charge the electric field cannot be detected until we interact with it. We vibrate our electron now we create a wave. Are vibrating electron creates an electric field which much like electricity running through a wire creates a magnetic field. And than are magnetic field again creates an electric field and so on and so on. Now do to electricity being a vector field it moves forward though space. Now when we say a wave you think we'll there must be something the wave moves through something much like a wave on the ocean is made if water. But think of space as as parking lot. And our wave could be sand blowing across it. The sand doesn't need the parking lot to do anything it already has momentum and direction do to energy it's been given. You want to know what space is made if that's just it it's not made of anything it's a lack of anything.

originally posted by: ImaFungi

originally posted by: mbkennel


Have you looked through the textbooks and videos I suggested before?

It looks like a point charge (radial electric field) plus a point dipole on the magnetic field.

Textbook drawings of magnetic field lines, is the closest pictorial representation of what this complex and mysterious and fundamental essential and substantial energetic medium appears as and exists as objectively? You know I am familiar with a point and lines extending away from it drawn in the sand, this can not give you an accurate comprehension as to how reality exists and appears to itself, objectively. This is a crude belittlement.

Indeed. That's why you read the rest of the chapter of the physics books as well and every bit of the detail you need is there because the answer you want is in Maxwell's equations. The electric field from a point charge is the vector gradient of the potential which is q/r^2. Learn how to take gradients in polar coordinates in 3-space. There's a chapter on magnetic dipoles too, read it.

The lines you see in the pictures are like 'streamlines' in a wind tunnel.

originally posted by: mbkennel


The EM field is produced by adding up contributions from ALL charges in the universe.

If you do not add up contributions from all charges in the universe, does the EM field still exist?

Is there 'something' (something = non nothing) which exists prior to and independently of charges? Or do charges and only charges themselves sputter out an endless supply of local EM field web?

Charges exist. If hypothetically we removed the existence of all charged particles, whether or not we could detect it, would EM field exist?

Then under the same conditions, after removing the existence of all charged particles; we bring one back into existence. Does the EM field exist as an independent entity, or do you believe that if there was only 1 charged particle in reality, that charged particle would be the source of creation and existence of a real EM field that extended throughout reality?



And I will write in a more efficient manner what i wanted to know and was getting at in my previous reply, that was a simplified version of the crux of my wonderings;


-------------------->

electron moving across the screen.

2 situations;
1. Electron moving from bottom of the screen upwards.
2. EM radiation moving from the bottom of the screen upwards.

We have detectors on screen right, left, up, down, and 4 corners. (to bring it into 3d, you need to consider dimension towards you and dimension behind the screen away from you, but also potentially then the corners in those directions, and this is why 3d gets cool and challenging because in regards to a point, there are infinite possible directions away from it (maybe) but a points surface area is finite, so this is why I ask, as any one purely interested in truth and reality should desire to ask, how an electron is attached to the EM field)

1. Where will EM radiation from this ----------> electrons acceleration be detected?
2. Where will EM radiation from this ----------> electrons acceleration be detected?

originally posted by: ImaFungi

originally posted by: mbkennel


The EM field is produced by adding up contributions from ALL charges in the universe.

If you do not add up contributions from all charges in the universe, does the EM field still exist?

You don't get a choice.

Is there 'something' (something = non nothing) which exists prior to and independently of charges?

Apparently so. In the best description of Nature, Standard Model, fundamental fields include electromagnetism and another is leptons and they aren't the same thing, but there is an interaction .

Or do charges and only charges themselves sputter out an endless supply of local EM field web?

Charges exist. If hypothetically we removed the existence of all charged particles, whether or not we could detect it, would EM field exist?

Yes, but it would be fairly boring. It may have electromagnetic radiation created in the Big Bang and nothing else, just photons flying around doing nothing. There may be some interactions between neutral particles and photons via the weak interaction (which is unified with electromagnetism at higher energies).

Then under the same conditions, after removing the existence of all charged particles; we bring one back into existence. Does the EM field exist as an independent entity, or do you believe that if there was only 1 charged particle in reality, that charged particle would be the source of creation and existence of a real EM field that extended throughout reality?

In the understanding of Standard Model, EM and other particles are different things. So you would have the EM field in its vacuum state a priori (or in whatever state its initial conditions were set), and with the creation of a charged particle this particle would then interact with the field.

In Standard model it is assumed all the fields of Nature were born at once, electrons are persistent 'excitations' of the lepton field and photons are the equivalent for EM field. In practice, there are conservation laws and positive mass on electrons which don't apply to photons, so photons appear to be much more ephemeral (as they are).

-------------------->

electron moving across the screen.

2 situations;
1. Electron moving from bottom of the screen upwards.
2. EM radiation moving from the bottom of the screen upwards.

We have detectors on screen right, left, up, down, and 4 corners. (to bring it into 3d, you need to consider dimension towards you and dimension behind the screen away from you, but also potentially then the corners in those directions, and this is why 3d gets cool and challenging because in regards to a point, there are infinite possible directions away from it (maybe) but a points surface area is finite, so this is why I ask, as any one purely interested in truth and reality should desire to ask, how an electron is attached to the EM field)

1. Where will EM radiation from this ----------> electrons acceleration be detected?
2. Where will EM radiation from this ----------> electrons acceleration be detected?

At a simple level, the radiation going up will catch up to the electron going up (as it's faster), and wiggle the electron left and right a little bit while it's still moving up. This will re-emit radiation. The shape of the pattern of radiation can be calculated, and is not ultra simple. You would consider it to be radiation from a moving dipole. The dipole (oscillating electron) is moving in one direction and oscillating in a perpendicular direction to its bulk motion.

If the electron is moving non-relativistically (much slower than 'c') then the radiation emitted will be that standard calculated from a stationary dipole transformed to be moving along with the charge.

ocw.mit.edu...

See 4.4.3, in particular 4.82. The intensity (energy flux) of emitted radiation is proportional to (dv/dt) * 1/c * sin^2 alpha.

Where v(t) is the oscillatory velocity of the electron, and alpha the angle between the direction you're measuring the emitting radiation and the acceleration vector.

So in our scenario, the electron has bulk movement up (if it's slow this is irrelevant), and is oscillating left to right on the x-axis. Thus you measure the angle between the x-axis and the direction of radiation you want to measure find it's angle (in 3-d space) and so the angular pattern is given by sin^2 of that angle. This means that the radiation is emitted strongest (sin^2 = 1) in the up and down direction (as the acceleration is left and right) and zero in the left and right direction (i.e. you are look 'eye on' to the acceleration direction).

If the electron is moving quite fast it gets more complicated. The maximum radiation intensity will appear to be in a cone around the direction of relativistic travel.

See 4.5

You're asking questions which can best be answered by learning classical electromagnetism for real. You've avoided it for a couple of years.

originally posted by: mbkennel


"The EM field is produced by adding up contributions from ALL charges in the universe." - you

"If you do not add up contributions from all charges in the universe, does the EM field still exist?" - me

You don't get a choice. - you

I was poking fun through the holes in your wording. The EM field is produced by adding up....not its not... the EM field exists, it is coupled to all charges in the universe. It is not produced when man begins to add up charges. Charged particles exist. The EM field exists. Some how they are intimately attached, so that when a charge moves the EM field moves.

Apparently so. In the best description of Nature, Standard Model, fundamental fields include electromagnetism and another is leptons and they aren't the same thing, but there is an interaction .

The EM field that exists. Is it a web, a 3d/4d graph of line energy? Is it a densely packed ocean of real photons?

An electron exists..... *

How is it attached to the EM field and what is the EM field physically/materially/energetically/substantially/essentially?


If this information is contained in volumes of textbooks that you have read and know and understand, you should be able to tell me right now.


electron..... *

are there 99999999^999999 tiny photon particles attached in an unbreakable chain bond to one another, and then also attached to the electron?

Draw a point on a piece of paper, and then try and draw how you know the EM field is coupled to the electron, and then tell me what sort of substance the EM field you drew is composed of. Tell me how if it exists independently of charged particles, what it is composed of and how it has no rest mass. Tell me how the EM field, it exists as a dense
ocean of particular material energy which is coupled to charge particles, tell me why this dense ocean of particular material energy 'waves' away from the acceleration of a charge? And how it doesnt wave like other particles in mediums we are familiar with, tell me how the medium designates 2d lines only connected in certain spots of the imaginary 1d point, waves away in a certain 2d direction, without 3d/4dly rippling the entire local EM surroundings of the charge?

Yes, but it would be fairly boring. It may have electromagnetic radiation created in the Big Bang and nothing else, just photons flying around doing nothing. There may be some interactions between neutral particles and photons via the weak interaction (which is unified with electromagnetism at higher energies).

If the EM field exists everywhere, you need to admit that photons exist everywhere, the ones in which you refer to as 'flying around' or 'detected' are merely larger than average, or, not larger than average, but the rest mass of a portion of the EM field, with relative energy.

A perfect still bath tub of water, lets imagine as the EM field. You say there are no photons, I say the EM field is an energy dense medium composed entirely of energy/matter call them photons if youd like. I take a marble (charged particle) and touch it to the surface of the still tub of water, and ripples are created. You say photons are now flying around. or we say, the EM field has locally been excited due to an acceleration of mass coupled to it. I say it is all photons, just that relative areas of the photon field are now moving with relative motion, the average energy of a local area was increased.

At a simple level, the radiation going up will catch up to the electron going up (as it's faster), and wiggle the electron left and right a little bit while it's still moving up. This will re-emit radiation. The shape of the pattern of radiation can be calculated, and is not ultra simple. You would consider it to be radiation from a moving dipole. The dipole (oscillating electron) is moving in one direction and oscillating in a perpendicular direction to its bulk motion.

If the electron is moving non-relativistically (much slower than 'c') then the radiation emitted will be that standard calculated from a stationary dipole transformed to be moving along with the charge.

ocw.mit.edu...

See 4.4.3, in particular 4.82. The intensity (energy flux) of emitted radiation is proportional to (dv/dt) * 1/c * sin^2 alpha.

Where v(t) is the oscillatory velocity of the electron, and alpha the angle between the direction you're measuring the emitting radiation and the acceleration vector.

So in our scenario, the electron has bulk movement up (if it's slow this is irrelevant), and is oscillating left to right on the x-axis. Thus you measure the angle between the x-axis and the direction of radiation you want to measure find it's angle (in 3-d space) and so the angular pattern is given by sin^2 of that angle. This means that the radiation is emitted strongest (sin^2 = 1) in the up and down direction (as the acceleration is left and right) and zero in the left and right direction (i.e. you are look 'eye on' to the acceleration direction).

If the electron is moving quite fast it gets more complicated. The maximum radiation intensity will appear to be in a cone around the direction of relativistic travel.

See 4.5

You're asking questions which can best be answered by learning classical electromagnetism for real. You've avoided it for a couple of years.

I dont know if you particularly understood my question and diagram.

---------->

That represents 1 electron. That represents the electron which I want to know after it is accelerated where its EM radiation will propagate.

Because I was unsure of the possibility of an electron itself ever causing another electron to accelerate, due to the fact that prior to the electron itself touching another electron, its EM field will cause it to accelerate,( this may be minutia in that no things may ever touch, only EM fields touch), I proposed 2 scenarios in which one may or may not be possible to most safely insure you answering my question.

an electron moving from the left of the screen to the right ------------>
and we want to know, when this electron is accelerated, where will its EM radiation be detected.

The example I offer for you to express where you believe you know -------> this electrons EM radiation will be detected is; Energy/substance/Em radiation traveling from the bottom of the screen upwards.

This is an endless chicken and the egg thing, because I am trying to comprehend how EM radiation exists fundamentally, and I must use EM radiation in this thought experiment, to hope to determine and further my knowledge of how EM radiation exists.

But anyway.

Electron traveling this way, slowly. ------------>

EM radiation, or an electron, is traveling from the bottom of the screen upwards and will hit the -------> electron on the arrow.

Is the EM radiation that is traveling from the bottom of the screen upwards doing so as a thin line, as a bullet, or as a wide ocean like wave, would the EM radiation be the width of the screen traveling upwards to meet the arrow? Or for the example that most mimics reality would it be an arrow like bullet that hits the -------> arrow? Or because you believe in 2d if the wave was the width of the screen for this example, you could equally imagine it being turned 90 degrees, and th

a reply to: mbkennel

(continued)

And then it would appear as a thin line, or bullet, but from another perspective we would see that its not.

So, we have detectors on all sides and corners of the screen.

---------------->



that arrow which is an electron, is hit by EM radiation traveling from the bottom of the screen upwards.

Where is the EM radiation, created by the electron ----> arrows attachment to its local EM field detected?

Why I mention the wave of EM radiation the width of the screen, is because it may be a true relation to reality, and because it would go into expressing how difficult it might be to keep track of what radiation goes where.

If a quantity of radiation is heading towards an electron with lesser mass relative to the quantity of radiation heading towards it, than after the contact, there will still be initial radiation going on its way, of course one can calculate the quantity of EM radiation related to the electrons mass and relative velocity that would be accounted for solely by the Electrons existence and attachment to the EM field, but what I am asking for, is where the directions of that EM radiation would be propagated towards.

originally posted by: ImaFungi

originally posted by: mbkennel


"The EM field is produced by adding up contributions from ALL charges in the universe." - you

"If you do not add up contributions from all charges in the universe, does the EM field still exist?" - me

You don't get a choice. - you

I was poking fun through the holes in your wording. The EM field is produced by adding up....not its not... the EM field exists, it is coupled to all charges in the universe. It is not produced when man begins to add up charges. Charged particles exist. The EM field exists. Some how they are intimately attached, so that when a charge moves the EM field moves.

Apparently so. In the best description of Nature, Standard Model, fundamental fields include electromagnetism and another is leptons and they aren't the same thing, but there is an interaction .

The EM field that exists. Is it a web, a 3d/4d graph of line energy? Is it a densely packed ocean of real photons?

An electron exists..... *

How is it attached to the EM field and what is the EM field physically/materially/energetically/substantially/essentially?

If this information is contained in volumes of textbooks that you have read and know and understand, you should be able to tell me right now.

Yes I can tell you right now: read the textbooks. The mathematics is established and the physical consequences unambiguous.

Whatever picture, or texture, or smell, or interior represtentation in your head you want, you alone have to manufacture it from your experience and understanding of the mathematics.

What counts as "how"? The Maxwell equations give complete solutions of partial differential equations with charges classically. If you want to go to QFT, then interaction terms from leptons and photons are defined concretely and both are the closest answers to "how", as in, if charges do this, then fields do that and vice versa. As there is no known substructure beneath either electrons or photons it doesn't make sense to answer "how" in any other way. There are no gears or little elves inside pulling on strings.

originally posted by: ImaFungi


an electron moving from the left of the screen to the right ------------>
and we want to know, when this electron is accelerated, where will its EM radiation be detected.

The example I offer for you to express where you believe you know -------> this electrons EM radiation will be detected is; Energy/substance/Em radiation traveling from the bottom of the screen upwards.

This is an endless chicken and the egg thing, because I am trying to comprehend how EM radiation exists fundamentally, and I must use EM radiation in this thought experiment, to hope to determine and further my knowledge of how EM radiation exists.

Try playing with this.

phet.colorado.edu...

EM radiation, or an electron, is traveling from the bottom of the screen upwards and will hit the -------> electron on the arrow.

Is the EM radiation that is traveling from the bottom of the screen upwards doing so as a thin line, as a bullet, or as a wide ocean like wave, would the EM radiation be the width of the screen traveling upwards to meet the arrow? Or for the example that most mimics reality would it be an arrow like bullet that hits the -------> arrow?

Could be either one. At lower frequencies typical for say optics to radio waves, then it's typical to consider it almost like a plane wave, meaning a wave very wide compared to the oscillatory motion induced in the electron.

The link I gave previously gives full results on where the radiation would be detected. If you shake a non-relativistic electron to the left and to the right, the radiation will be given off in a 'figure-8' pattern with the bulbs of maximum intensity pointing up and down, and minimum intensity pointing left and right, proportional to sin^2 a, with a being the angle in 3-space between the oscillatory vector (left and right) and the place you're measuring radiation intensity.

originally posted by: mbkennel



The link I gave previously gives full results on where the radiation would be detected. If you shake a non-relativistic electron to the left and to the right, the radiation will be given off in a 'figure-8' pattern with the bulbs of maximum intensity pointing up and down, and minimum intensity pointing left and right, proportional to sin^2 a, with a being the angle in 3-space between the oscillatory vector (left and right) and the place you're measuring radiation intensity.

Ok, so simplifying reality to 2d, it is shown that any time an electron is accelerated, EM radiation will be propagated away from the electron 360 degrees surrounding it? True?

Does any physicist understand how the electron is attached to the EM field? And what the electron is attached to? Is the electron always attached to a field of resting photons? A pool of virtual photons (which means, lets argure about what virtual particles means)? Is the EM field at points that are not excited, photons?

(by the way, the 2d simplifications also screw with your comprehension of gravity and how it works... The 2d imaginings of a fabric warped gives you a simplistic but ultimately faulty comprehension of how gravity must work and how it must exist, how reality must be, when I ask you to imagine how gravity really works, how mass is really coupled to a 3d/4d material/energy field and what it really means that it warps, what do you imagine?) (After you answer my 360 degree question above, I will want to know, as that is the expression of electron in 2d simplicity, how you comprehend EM radiation responding to an electrons acceleration, in reality, 3d/4d space, 3d/4d EM field.) (Do you agree that just because a person has more symbols stored in their memory does not mean they are smarter than me?)

originally posted by: ImaFungi

originally posted by: mbkennel



The link I gave previously gives full results on where the radiation would be detected. If you shake a non-relativistic electron to the left and to the right, the radiation will be given off in a 'figure-8' pattern with the bulbs of maximum intensity pointing up and down, and minimum intensity pointing left and right, proportional to sin^2 a, with a being the angle in 3-space between the oscillatory vector (left and right) and the place you're measuring radiation intensity.

Ok, so simplifying reality to 2d, it is shown that any time an electron is accelerated, EM radiation will be propagated away from the electron 360 degrees surrounding it? True?

No, it depends on the particular motion of the electron. sin^2 alpha = 0 for alpha = 0 and pi, so for some particular directions you wouldn't see any radiation. If, for instance, the electron oscillates in a small circle, then if you still look in that 2-d plane, there would indeed be radiation in all 360 degrees.

Does any physicist understand how the electron is attached to the EM field?

In classical E&M yes.

And what the electron is attached to?

In classical E&M yes.

Is the electron always attached to a field of resting photons? A pool of virtual photons (which means, lets argure about what virtual particles means)? Is the EM field at points that are not excited, photons?

The connection between classical EM fields and the quantized photons is not easy to visualize given that in QFT you are dealing with a wavefunction of a function. Roughly the photons are like the fourier expansion coefficients of fields, but the expansion of classical E&M in the long wavelength limit in terms of individual photons, real or not, is often not enlightening. It works much better when you get to (not surprisingly) quantum phenomena like x-ray scattering.

The full real theory is called 'quantum optics' and is the closest explanation of what a photon REALLY is, but you probably have to have at least a semester of graduate quantum mechanics first to understand it, and to get that point you've already gone through a year of classical electromagnetism and undergraduate QM.

(by the way, the 2d simplifications also screw with your comprehension of gravity and how it works... The 2d imaginings of a fabric warped gives you a simplistic but ultimately faulty comprehension of how gravity must work and how it must exist, how reality must be, when I ask you to imagine how gravity really works, how mass is really coupled to a 3d/4d material/energy field and what it really means that it warps, what do you imagine?)

It's quite difficult to visualize. Perhaps there are simulators that help.

(After you answer my 360 degree question above, I will want to know, as that is the expression of electron in 2d simplicity, how you comprehend EM radiation responding to an electrons acceleration, in reality, 3d/4d space, 3d/4d EM field.)

The Lienard-Wiechert potentials can help you calculate the resulting fields from generalized motion of charges.

They integrate over the location of where charges used to be ("retarded time") at some distance away (propagating at 'c'), and then you take gradients and curl of these to get your electric and magnetic fields. See the section Equations here: en.wikipedia.org...

in the expressions for E() and B() there is a first term plus a second term. The first term is the 'near' contribution to the field, and in quantum mechanics might be assocaited with 'virtual photons', and the second is the radiation field which is associated with real photons which can propagate to infinity and carry energy & momentum.

(Do you agree that just because a person has more symbols stored in their memory does not mean they are smarter than me?)

Sure. It depends on what they do with them. You aren't dumb, but you're very stubborn about NOT learning things the way it works with everybody else who had to learn them. You're trying to lasso gnarly bulls but don't want to put on boots or learn to ride the horse.

a reply to: mbkennel

...quantum phenomena like x-ray scattering.

What is so special about x-rays than the other frequencies... what do you mean exactly ?

originally posted by: KrzYma
a reply to: mbkennel

...quantum phenomena like x-ray scattering.

What is so special about x-rays than the other frequencies... what do you mean exactly ?

The wavelengths are smaller, so you deal with the sorts of volumes where the quantum behavior is more prominent than, say, a 10 meter radio wave.

a reply to: Bedlam

Yes, thanks, I know that, I'm looking for the quantum part in x-ray diffraction,
all I can see is electro magnetic fields and charges...

here why
www.youtube.com...

diffraction is a diffraction, you can give it any name it still doesn't puts what's going on into another theory.

originally posted by: KrzYma
a reply to: Bedlam

Yes, thanks, I know that, I'm looking for the quantum part in x-ray diffraction,
all I can see is electro magnetic fields and charges...

The quantum analysis doesn't deny the existence of electromagnetic fields and charges. The quantum analysis says that the electromagnetic energy from the x-rays is quantized into "wave packets" (which can be referred to as exhibiting the "particle-like" behavior of EM). These quantized "wave packets" are not present in classical wave theory which is why classical wave theory doesn't explain some X-ray diffraction observations.

Did you notice in the video you posted that he treats each electron similar to the way we treat slits in a double slit experiment? And did it occur to you that the electron is not really like a slit? So he doesn't really explain why x-rays would behave like he shows in that course, because it's for students unfamiliar with QM. This is the explanation not included in the video you posted, for why X-rays would behave in the way he shows:

www.users.csbsju.edu...


See Compton Scattering and inverse Compton scattering experiments to gain more insight into the interaction of photons and electrons.

a reply to: ImaFungi

I am not sure physics can give you the answer you are looking for.

There is matter. Matter interacts with other matter. Everything else is math...

Matter can be modeled as particles or fields (field quanta to be more correct).

Matter interaction can be modeled as force carrying particles or fields (field quanta).

Why there is matter and why it interacts the way it does, is something that is out of scope of physics, imho.