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What is Magnetism ?

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What exactly is Magnetism ?

 

Does it always coexist with Electricity ?

 

What is Electricity ?

 

What is the maximum to which Voltage an Electric Potential can be built up ?

 

Is there a similar limit to Magnetic Strength ?

 

Why are we unable to magnetize all materials ?

 

What is light ?

 

Why is light called an Electromagnetic Wave ?

 

What is a Wave ?

 

What exactly is the Wave Movement and Wave theory in a nutshell ?

 

What is the relation between Sound, Force, Heat, Light and Electromagnetism ?

 

How much Noise/thunder/Sound will emanate from Sun [in decibels] apart from other Energies ?

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You've asked a lot of very involved questions here. It won't surprise me of the thread gets confused.

 

 

What exactly is Magnetism ?

 

A magnetic field is a relativistic effect of an electric field.

 

Does it always coexist with Electricity ?

 

Magneto statics can be studied, as can electrostatics, but they are fundamentally entwined, you always need charge.

 

What is Electricity ?

Flow of charge.

 

 

What is the maximum to which Voltage an Electric Potential can be built up ?

 

Depends on the situation. Lightning has a much higher potential difference compared to say car battery sparking.

 

Is there a similar limit to Magnetic Strength ?

 

It depends.

 

Why are we unable to magnetize all materials ?

Ferromagnetism (and ferry, para et...) are complicated, you need to know a lot about the atomic structure of the solid to understand this on a fundamental level.

 

 

What is light ?

 

Electromagnetic wave/photons of a wavelength that is visible to a human.

 

Why is light called an Electromagnetic Wave ?

Because that's what our is, a bootstrapping wave of E and B fields.

 

 

What is a Wave ?

 

Something that exhibits wave type properties.

 

What exactly is the Wave Movement and Wave theory in a nutshell ?

 

Things oscillate. Sometimes they process as they oscillate. This is a BIG subject, a forum post couldn't hope to do or justice.

 

What is the relation between Sound, Force, Heat, Light and Electromagnetism ?

Sound is a wave.

Light is a wave.

Light an electromagnetic phenomena.

Force is the rate of change of momentum.

Waves can transfer momentum.

Heat is energy transfer.

Waves can transfer energy.

Force is the differential of energy. (Ish)

 

 

 

How much Noise/thunder/Sound will emanate from Sun [in decibels] apart from other Energies ?

None, it cannot propagate in vacuum.

 

 

Most of these answers are pretty vague generalisations. You'd need specifics and maths for much more.

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You've asked a lot of very involved questions here. It won't surprise me of the thread gets confused.

 

 

 

A magnetic field is a relativistic effect of an electric field.

 

 

Magneto statics can be studied, as can electrostatics, but they are fundamentally entwined, you always need charge.

 

 

Flow of charge.

 

 

Depends on the situation. Lightning has a much higher potential difference compared to say car battery sparking.

 

 

It depends.

 

 

Ferromagnetism (and ferry, para et...) are complicated, you need to know a lot about the atomic structure of the solid to understand this on a fundamental level.

 

 

Electromagnetic wave/photons of a wavelength that is visible to a human.

 

 

Because that's what our is, a bootstrapping wave of E and B fields.

 

 

Something that exhibits wave type properties.

 

 

Things oscillate. Sometimes they process as they oscillate. This is a BIG subject, a forum post couldn't hope to do or justice.

 

 

Sound is a wave.

Light is a wave.

Light an electromagnetic phenomena.

Force is the rate of change of momentum.

Waves can transfer momentum.

Heat is energy transfer.

Waves can transfer energy.

Force is the differential of energy. (Ish)

 

 

 

None, it cannot propagate in vacuum.

 

 

Most of these answers are pretty vague generalisations. You'd need specifics and maths for much more.

 

Thank you.

 

+1 for the Effort.

 

I always want to understand more !

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Does it always coexist with Electricity ?

This is a very important point. We really have the electromagnetic field which describes both the electric and magnetic fields at the same time. You cannot really disentangle the two in a fundamental way. Via Lorentz transformations, the electric field in one inertial frame can contribute to the magnetic field in another inertial frame. And of course vice-versa. Seeing the two as separate is really not possible.

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This is a very important point. We really have the electromagnetic field which describes both the electric and magnetic fields at the same time. You cannot really disentangle the two in a fundamental way. Via Lorentz transformations, the electric field in one inertial frame can contribute to the magnetic field in another inertial frame. And of course vice-versa. Seeing the two as separate is really not possible.

Hi, Thank you.

 

I'll try and reconcile those ideas.

 

Thanks again.

 

+1 for you

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commander

What exactly is Magnetism ?

 

For the most part we cannot answer a question "What is XXX ?"

 

The best we can do is create models.

 

We obtain observations and measurements and call the sum of all htis the real world.

Clearly since new observations and measurements are continually being made the 'real world' is continually being updated (like Microsoft Windows :eek: )

 

We also create completely abstract constructs with artificial rules and relationships.

Many are mathematical.

Some of these can be used to model observations and measurements in the real world and even make predictions.

But none of these models are exact or perfect.

 

Magnetism is a case in point.

 

We know today that the source of all magnetic effects is electric in origin.

 

But a simple model,

That of the separate existence of a magnetic force affecting certain objects

for some purposes will make the required prediction easier.

 

On another forum I posed a calculation question about lifting a car in a scapyard with a crane magnet.

 

Members there disputed non electrical explanations and one member with a PhD and many years experience in electrical and magnetic matters finally showed several pages of vector mechanics to calculate the selfsame result I had achieved in three lines.

 

I employed what is known as the method of Virtual Work, and did not need to mention electricity at all.

 

So your question really need lots of context to provide a sensible answer.

What are you actually seeking to know?

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This is a very important point. We really have the electromagnetic field which describes both the electric and magnetic fields at the same time. You cannot really disentangle the two in a fundamental way. Via Lorentz transformations, the electric field in one inertial frame can contribute to the magnetic field in another inertial frame. And of course vice-versa. Seeing the two as separate is really not possible.

Hi, Thank you.

 

I'll try and reconcile those ideas.

 

Thanks again.

 

+1 for you

 

You should try voting again, I don't think ajb did receive your +1.

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For the most part we cannot answer a question "What is XXX ?"

 

The best we can do is create models.

 

We obtain observations and measurements and call the sum of all htis the real world.

Clearly since new observations and measurements are continually being made the 'real world' is continually being updated (like Microsoft Windows :eek: )

 

We also create completely abstract constructs with artificial rules and relationships.

Many are mathematical.

Some of these can be used to model observations and measurements in the real world and even make predictions.

But none of these models are exact or perfect.

 

Magnetism is a case in point.

 

We know today that the source of all magnetic effects is electric in origin.

 

But a simple model,

That of the separate existence of a magnetic force affecting certain objects

for some purposes will make the required prediction easier.

 

On another forum I posed a calculation question about lifting a car in a scapyard with a crane magnet.

 

Members there disputed non electrical explanations and one member with a PhD and many years experience in electrical and magnetic matters finally showed several pages of vector mechanics to calculate the selfsame result I had achieved in three lines.

 

I employed what is known as the method of Virtual Work, and did not need to mention electricity at all.

 

So your question really need lots of context to provide a sensible answer.

What are you actually seeking to know?

 

Hi Studiot,

 

Thank you for the elaborate response.

 

+1 to you in response.

 

I have many questions and I have this habit of testing every theory and feeling the evidence before accepting anything. Would like to be Logical, Deducing and Creative as well.

 

As you and other respondents have rightly stated what we know and think and what is still to be understood I keep contemplating on the intricacies of Magnets, Batteries and charge holders as well as the energy flowing out of them.

 

One of my dream Project is : If we can master and control magnetic fields we can build an invisible magnetic road from point to point on which cars can simply ride on or hang on to and reach the destination.

 

More later ........

Edited by Commander

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commander

As you and other respondents have rightly stated what we know and think and what is still to be understood I keep contemplating on the intricacies of Magnets, Batteries and charge holders as well as the energy flowing out of them.

 

 

Be aware of the difference between force and energy.

 

Magnets do not have energy flowing into or out of them.

 

Magnetism is a force. Exerting a force may or may not involve energy.

 

For example the Earth continues to exert a force on you through gravity, but no energy flows into or out of the Earth, unless you fall out of the sky.

 

In the same way a magnet may cause another body to move, doing work in the process.

But something moves or holds the magnet.

 

This is like poking something with a stick so it moves or drawing it along with a string.

Either way the stick or string exerts a force on the object, but something else has to push or pull the other end.

 

If the object does not move then the force can remain exerted till kingdom come and no work is done, so no energy flows.

Edited by studiot

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You should try voting again, I don't think ajb did receive your +1.

 

Hi, T Y. I did correct it.

 

Even this reply to you I am repeating as it vanished.

 

My tablet too goes off now and then making posting laborious.

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Each particle has properties: charge and "elementary magnet" ("magneton").

When their properties don't cancel at quantum level, we can observe their effects at macroscopic level.

 

f.e.

when charges cancel we have non-polar liquid,

when charges don't cancel we have polar liquid (f.e. water).

when elementary magnets cancel we have non-magnetized matter,

when elementary magnets don't cancel we have various types of magnetized matter.

 

Imagine how electromagnet is made:

we have non-magnetized *) iron bar, entwined by wire with length d, through which we pass current I.

The more current, the more charge per second:

Q=I*t

1 A * 1s = 1 Coulomb.

If we divide Q by e constant 1.602*10^-19 C, we receive quantity of electrons flowing per second through wire.

 

Strength of electromagnet is depending on current I and quantity of entwine. The higher I, the more Q, and the more electrons is flowing. And stronger electromagnet.

 

But you can't pass any current you want.

When you will pass too high current, wires will be overheated and melt.

This is limiting strength of electromagnet. Which should answer question about maximum possible magnetic strength.

 

Similar limit has also permanent magnet:

quantity of particles in permanent magnet bar is given by mass/molar mass.

f.e.

100 gram Iron / 56 g/mol = 1.78 mol * 6.022141*10^23 = 1.07538*10^24 iron particles.

Particles which can align the same way is smaller than that IIRC.

 

Maximum voltage you can have depends on breakdown voltage of used isolators.

http://en.wikipedia.org/wiki/Breakdown_voltage

Quantity of charged electrons (or holes) is limited by quantity of atoms used to make electrodes on which they will gather.

 

Imagine how permanent magnet is made:

we have non-magnetized iron bar (elementary magnets inside are randomly aligned),

we're entwining it by wire,

and starting heating iron bar (there is needed temperature > 770 C),

and at the same time passing current through wire.

(so basically making electromagnet)

and then continuing to pass current, while cooling iron bar.

Elementary magnets in iron bar freeze at state they gained at high temperature under influence of magnetic field created by electrons passing through wire.

 

*) if permanent magnet is used instead, we can destroy uniform alignment. Destroy permanent magnet.

Dropping of permanent magnet from too high altitude can also destroy magnetization.

Hitting it by hammer can also destroy magnetization.

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sensei

when charges don't cancel we have polar liquid (f.e. water).

 

 

What do you mean charges don't cancel?

 

Water is electrically neutral.

 

If you are referring to the eletrical dipole moments please expand as this could be confusing.

Edited by studiot

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What exactly is Magnetism ?

 

Does it always coexist with Electricity ?

 

As a fundamental force, it can't be explained in terms of other things. Like in mathematics, axioms do not result from theorems. Nor can you explain the taste of salt - but you can tell that seawater or oysters taste salty. What we know is how it behaves, how to make and use it.

 

Magnetism is created by a flow of charged particles - except for the less comfortable case of the magnetic dipole resulting from the spin of elementary particles, especially the electron. People happily observe that this magnetic dipole appears at charged particles - nice that the neutron was observed to be composed of several charged particles. Though, the particle's spin is not a geometric rotation, and the relationship between the particle's mass, mechanic moment and magnetic moment (so-called Landé factor) differs from a big rotating object.

What is the maximum to which Voltage an Electric Potential can be built up ?

 

Is there a similar limit to Magnetic Strength ?

 

Why are we unable to magnetize all materials ?

 

Electric potentials are relative to an other. We can't tell the electric potential of the Earth, the Galaxy... only if it differs from an other object and by how much. In that sense, absolutely no limit.

 

The potential differences are not limited, to my knowledge. Only the distance limits them. Sparks limit to 10kV/mm in the air and 50kV/mm in good plastics (the voltage isn't proportional to the distance); vacuum itself has a limited insulation capability - unless the electrodes are the reason, this domain isn't well known presently. At the scale of atoms and particles, you can get potential differences of 1MV over 100pm, a huge field far above our macroscopic capabilities - and then the creation of virtual electron+positron pairs limits the field.

 

Humans can make over 10MV for some duration, and achieve a huge field (not potential) at a short and concentrated laser pulse.

http://en.wikipedia.org/wiki/Femtosecond_laser

http://www.rp-photonics.com/titanium_sapphire_lasers.html

 

----------

 

No theoretical limit to the magnetic field, to my knowledge.

 

Magnetic fields resulting from ferromagnetic materials are limited by the dipole of electrons and the density of these active electrons in the solid, almost one per atom. This result in 2.3T in the Fe-Co alloy, very close to the computed limit.

 

Superconducting coils are limited by the superconductors to 10T or little more presently. But copper coils powered by short current pulses achieve >200T... a few times before they're destroyed.

 

Some laser pulses, short and concentrated, achieve a bigger magnetic field - an alternating one, and of short duration.

 

----------

 

Every material contains electrons and reacts to man-made magnetic fields. The effect on the electrons can be significant but only if some electrons are not paired and only with a big external field - the material's reaction isn't so remarkable: para- and dia-magnetism.

 

Electrons in living matter, plastics... tend to be paired, and their reaction to the external field is opposite and cancels out. Some molecules like O2 have unpaired electrons and show a less weak magnetism.

 

Only ferromagnetism is strong, that is, a small external action results in a big effect. This is because the material's electrons have already arranged among themselves, and the external action (man-made if you wish) just influences this order.

 

Ferromagnetic materials rely on electrons in two (or more?) different conditions that make magnetic dipoles of different strengths and are strongly coupled with an other. Now, imagine that the dipole strengths alternate in the material, like white and black on a chessboard. Neighbour dipoles adopt opposite orientations spontaneously just like big magnets do, but if the stronger and weaker dipoles alternate regularly, you get all the stronger in one direction and the weaker in the other, and the result is not zero. This is essentially a ferromagnetic material, present but not common in Nature.

 

This order holds within "Weiss domains", typically few µm big, which are spontaneously completely magnetized. These domains tend to orient themselves opposed to their neighbours, again like big magnets do. Though, two possibilites permit a global field:

 

- If the limits between the Weiss domains, called Bloch walls, move easily. This is a soft ferromagnetic material like transformer steel: an external field influences the dipoles at the walls (which get conflicting influences from both domains hence are sensitive to other actions) to flip in the favourable direction. Now, a limited external influence gets parts of the strong spontaneous magnetization in its favour, and the effect is strong.

 

- Or if the Bloch walls are hard to move but the previous history of the material put them out of the neutral position. This is a hard ferromagnetic material, or a permanent magnet, once it has been made.

 

Ferromagnetic materials often contain certain atoms like Fe, Ni, Co, Gd... but not necessarily: CrO2 is a permanent magnet but neither Cr nor O2 are, so it's molecular property. The opposite example are austenitic stainless steel which contain mainly iron but aren't ferromagnetic. Even some ferromagnetic plastics have been made.

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Like somebody stated, magnetism is a relativistic effect of the electric field, and electrical field are produced by electrical charges. What is an electric charge, and why does it create an electric field, that is difficult to answer since it is not something that was derived, but rather something be observed. it is rather cool that we can reduce electricity and magnetism down into two ideas, the electric charge and relativity.

 

If electric field could be described by bending of space-time like gravity is would all fit together nicely, but then again we don't know why mass bends space-time, only that is does. Though some quantum groupies might disagree with me.

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Like somebody stated, magnetism is a relativistic effect of the electric field, and electrical field are produced by electrical charges. What is an electric charge, and why does it create an electric field, that is difficult to answer since it is not something that was derived, but rather something be observed. it is rather cool that we can reduce electricity and magnetism down into two ideas, the electric charge and relativity.

 

If electric field could be described by bending of space-time like gravity is would all fit together nicely, but then again we don't know why mass bends space-time, only that is does. Though some quantum groupies might disagree with me.

 

What is an electric charge - what is it made of is a good question too

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What is an electric charge - what is it made of is a good question too

 

And the answer is we don't know. This is physics, not metaphysics. We describe how things behave, not what their nature is.

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As a fundamental force, it can't be explained in terms of other things. Like in mathematics, axioms do not result from theorems. Nor can you explain the taste of salt - but you can tell that seawater or oysters taste salty. What we know is how it behaves, how to make and use it.

 

Magnetism is created by a flow of charged particles - except for the less comfortable case of the magnetic dipole resulting from the spin of elementary particles, especially the electron. People happily observe that this magnetic dipole appears at charged particles - nice that the neutron was observed to be composed of several charged particles. Though, the particle's spin is not a geometric rotation, and the relationship between the particle's mass, mechanic moment and magnetic moment (so-called Landé factor) differs from a big rotating object.

 

Electric potentials are relative to an other. We can't tell the electric potential of the Earth, the Galaxy... only if it differs from an other object and by how much. In that sense, absolutely no limit.

 

The potential differences are not limited, to my knowledge. Only the distance limits them. Sparks limit to 10kV/mm in the air and 50kV/mm in good plastics (the voltage isn't proportional to the distance); vacuum itself has a limited insulation capability - unless the electrodes are the reason, this domain isn't well known presently. At the scale of atoms and particles, you can get potential differences of 1MV over 100pm, a huge field far above our macroscopic capabilities - and then the creation of virtual electron+positron pairs limits the field.

 

Humans can make over 10MV for some duration, and achieve a huge field (not potential) at a short and concentrated laser pulse.

http://en.wikipedia.org/wiki/Femtosecond_laser

http://www.rp-photonics.com/titanium_sapphire_lasers.html

 

----------

 

No theoretical limit to the magnetic field, to my knowledge.

 

Magnetic fields resulting from ferromagnetic materials are limited by the dipole of electrons and the density of these active electrons in the solid, almost one per atom. This result in 2.3T in the Fe-Co alloy, very close to the computed limit.

 

Superconducting coils are limited by the superconductors to 10T or little more presently. But copper coils powered by short current pulses achieve >200T... a few times before they're destroyed.

 

Some laser pulses, short and concentrated, achieve a bigger magnetic field - an alternating one, and of short duration.

 

----------

 

Every material contains electrons and reacts to man-made magnetic fields. The effect on the electrons can be significant but only if some electrons are not paired and only with a big external field - the material's reaction isn't so remarkable: para- and dia-magnetism.

 

Electrons in living matter, plastics... tend to be paired, and their reaction to the external field is opposite and cancels out. Some molecules like O2 have unpaired electrons and show a less weak magnetism.

 

Only ferromagnetism is strong, that is, a small external action results in a big effect. This is because the material's electrons have already arranged among themselves, and the external action (man-made if you wish) just influences this order.

 

Ferromagnetic materials rely on electrons in two (or more?) different conditions that make magnetic dipoles of different strengths and are strongly coupled with an other. Now, imagine that the dipole strengths alternate in the material, like white and black on a chessboard. Neighbour dipoles adopt opposite orientations spontaneously just like big magnets do, but if the stronger and weaker dipoles alternate regularly, you get all the stronger in one direction and the weaker in the other, and the result is not zero. This is essentially a ferromagnetic material, present but not common in Nature.

 

This order holds within "Weiss domains", typically few µm big, which are spontaneously completely magnetized. These domains tend to orient themselves opposed to their neighbours, again like big magnets do. Though, two possibilites permit a global field:

 

- If the limits between the Weiss domains, called Bloch walls, move easily. This is a soft ferromagnetic material like transformer steel: an external field influences the dipoles at the walls (which get conflicting influences from both domains hence are sensitive to other actions) to flip in the favourable direction. Now, a limited external influence gets parts of the strong spontaneous magnetization in its favour, and the effect is strong.

 

- Or if the Bloch walls are hard to move but the previous history of the material put them out of the neutral position. This is a hard ferromagnetic material, or a permanent magnet, once it has been made.

 

Ferromagnetic materials often contain certain atoms like Fe, Ni, Co, Gd... but not necessarily: CrO2 is a permanent magnet but neither Cr nor O2 are, so it's molecular property. The opposite example are austenitic stainless steel which contain mainly iron but aren't ferromagnetic. Even some ferromagnetic plastics have been made.

 

Like somebody stated, magnetism is a relativistic effect of the electric field, and electrical field are produced by electrical charges. What is an electric charge, and why does it create an electric field, that is difficult to answer since it is not something that was derived, but rather something be observed. it is rather cool that we can reduce electricity and magnetism down into two ideas, the electric charge and relativity.

 

If electric field could be described by bending of space-time like gravity is would all fit together nicely, but then again we don't know why mass bends space-time, only that is does. Though some quantum groupies might disagree with me.

 

 

What is an electric charge - what is it made of is a good question too

 

 

And the answer is we don't know. This is physics, not metaphysics. We describe how things behave, not what their nature is.

 

Hi All, [ +1 to each of you Enthalpy, CasualKilla & swansont ]

 

Yes its a heady mix of Ideas of which I am always enthralled and would like to unravel as much as we could and understand all intricacies.

 

Whether the Electric and Magnetic Fields and Energy traverses through a Conductor [normally viewed as drifting of charged particles like Electrons and Holes/Ions drifting through the media] or just through Space or in any other way as per the permittivity and conductivity,susceptibility and permeability etc as a Wave or Transmission it conveys and distributes Energy from Origin to some Destination While the actual Electrons transfer through may be slower the disturbance runs through the media at the high speed of say the speed of Electricity or Light. Depending on what is in its path the Energy might interact with the Space Matter with all its Quantum Mechanical Behaviour and takes different Forms like Momentum, Sound, Heat, assimilation into Mass/Matter etc.

 

All of us Humans owe our Life to such Energy supply from Sun through Radiation and Light [Electromagnetic Wave ?] and if that supply fails for a few months we can't post anymore in this forum !

 

We have many Theories each one proved with high mathematical Formulas in Vector Algebra etc and Multi Dimensional Analysis which I would like to analyze , understand and then Accept just as I accept 2+3 = 5 and after this understanding I can claim that I have knowledge in this area of Science ! Do I have an Uphill task ? Yes.

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What is an electric charge - what is it made of is a good question too

 

There is no evidence that charge is made of anything else. It appears to be one of the fundamental properties of matter.

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There is no evidence that charge is made of anything else. It appears to be one of the fundamental properties of matter.

 

And a thousand years ago we had no evidence that protons are made of anything. We didn't even have evidence for the protons themselves. Asking what something is made of is still a valid question.

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And a thousand years ago we had no evidence that protons are made of anything. We didn't even have evidence for the protons themselves. Asking what something is made of is still a valid question.

 

That's a different question, and we also have a lot more evidence today (especially considering that we didn't even know of atoms a thousand years ago). Charge is a property. So it makes as much sense as asking what tall is made of.

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I suspect the best you can hope for is that some or all "fundamental" properties turn out to be emergent properties from some lower-level theory (CDT, LQG, etc). Which just shifts the question to, why that theory, and why does it have the properties it does...

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That's a different question, and we also have a lot more evidence today (especially considering that we didn't even know of atoms a thousand years ago). Charge is a property. So it makes as much sense as asking what tall is made of.

 

Charge and tall aren't the same kind of property. Charge is a physical property that can be measured, while tall is a subjective property that can't be measured. The fact that charge can be measured makes the question 'What is it?' completely valid.

 

At the most fundamental level you can ask that question about anything. What's a photon? Photons are fundamental particles, right? From what I understand about this it means that they aren't made of smaller particles. The question is whether or not that means that they aren't made of anything and simply are ('made' of themselves, so to speak). Then there's also the possibility that they are made of something, just not particles, and not something that we could hope to measure right now. Could take ten thousand years to discover that, for all we know. Or it's not possible for us to measure this if it's so.

 

Asking what something is, is completely valid.

Edited by Thorham

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Charge and tall aren't the same kind of property. Charge is a physical property that can be measured, while tall is a subjective property that can't be measured. The fact that charge can be measured makes the question 'What is it?' completely valid.

 

I can't measure how tall something is? Really? I have a meter stick, which is by definition one meter tall, to use as a basis for comparison.

 

At the most fundamental level you can ask that question about anything. What's a photon? Photons are fundamental particles, right? From what I understand about this it means that they aren't made of smaller particles. The question is whether or not that means that they aren't made of anything and simply are ('made' of themselves, so to speak). Then there's also the possibility that they are made of something, just not particles, and not something that we could hope to measure right now. Could take ten thousand years to discover that, for all we know. Or it's not possible for us to measure this if it's so.

 

Asking what something is, is completely valid.

 

Valid, sure. But that doesn't mean science can answer it, or is prepared (even in principle) to try. i.e. it doesn't mean it's a science question as opposed to one from a different branch of philosphy.

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I can't measure how tall something is? Really? I have a meter stick, which is by definition one meter tall, to use as a basis for comparison.

Right, you mean length. Thought you meant the subjective tall (I'm tall compared to a mouse, but short compared to an elephant).

 

Asking what length is, is valid. For items made of atoms, it's more or less the number of atoms along a straight line between the two measuring points... or something like that ;) The involved 'stuff' is atoms.

 

In the case of electric charge, it's an abundance or shortage/absence of electrons. Here the 'stuff' that's involved is electrons.

 

Now, how do we answer this for magnetism? What's the involved 'stuff' here?

 

 

Valid, sure. But that doesn't mean science can answer it, or is prepared (even in principle) to try. i.e. it doesn't mean it's a science question as opposed to one from a different branch of philosphy.

Perhaps, but what if some of those questions can be answered? You're obviously (probably) going to hit a wall at some point. A point where you can't go farther because nature won't let you, or because you've simply arrived at the end. Until that happens, these questions must be asked.

Edited by Thorham

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In the case of electric charge, it's an abundance or shortage/absence of electrons. Here the 'stuff' that's involved is electrons.

 

Even for a single electron? Or a muon? Or a quark?

 

Now, how do we answer this for magnetism? What's the involved 'stuff' here?

As already stated, it is the same thing from a different frame of reference: charge + relativity = electromagnetism.

 

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