/sci/ - Science & Math

[Anonymous No.10431999]

How does current generate a magnetic field ? What's the reason on an atomic or subatomic level, what is creating that field ?

[Anonymous No.10432010]

>>10431999
if you find out let the rest of humanity know

[Anonymous No.10432016]

>>10431999
to answer your question in reverse, special relativity

[Anonymous No.10432022]

>>10432016
>special relativity
what's so special about it ?

[Anonymous No.10432040]

>>10432022
its special because it makes electricity

[Anonymous No.10432051]

>>10431999
>How does current generate a magnetic field ?
They’re aspects of the same phenomenon, electromagnetism, which is itself caused by the property of charge present in subatomic particles. Why are particles charged? They just are.

[Anonymous No.10432066]

>>10432051
Yeah along with radioactive decay in electro-weak force, but I've never watched my wire decay radiatively from running a current through it

[Anonymous No.10432096]

>>10431999
Because a moving electron generates photons, and photons move at the speed of light.
https://www.youtube.com/watch?v=1TKSfAkWWN0

[Anonymous No.10432100]

>>10432066
what’s your point

[Anonymous No.10432456]

>>10431999
something along the lines of fermions interacting with the quantum foam and such.

[Anonymous No.10432464]

>>10431999
well you see you get a bunch of atoms here, there and everywhere and they're all slightly spaced apart so you get different shapes you can trace between them and then ya

[Anonymous No.10432469]

>>10432100
That your answer doesn't provide any explanation other than here's a word and I'm saying it's the same thing

[Anonymous No.10432480]

>>10432096
I feel like it must be slightly more complicated than that.
If magnetic monopoles existed couldn't you just do the exact same thing in reverse and explain electricity as an effect of special relativity on magnetism?

[Anonymous No.10432487]

Good question.

[Anonymous No.10432501]

>>10432480
Maybe, but magnetic monopoles don't exist precisely because magnetism is a made up force from back when people didn't understand that the forced induced from one particle to another propagate at a limited speed.
Magnetism effectively is just an artifice to explain electrodynamic phenomena without special relativity, it adds no predictive power at all to physics once you take the speed of light into account.

[Anonymous No.10432506]

>>10431999

[Anonymous No.10432516]

>>10431999
Forcing current through a conductor causes the atoms in the metal to align their charges, making a (strong enough to be felt) magnetic field

[Anonymous No.10432569]

>>10432469
Sorry to burst your bubble but there is no deeper explanation beyond that though. Charged particles create electromagnetic fields. It’s a fact of nature.

[Anonymous No.10432610]

>>10431999
I believe it's the photons causing that force, but the photons that are generated by moving electrons exist in the past only.

[Anonymous No.10432643]

so a coil creates a magnetic field but not a straight wire because you are forcing the electrons to change direction through the coil and therefore accelerate by defintion and accelerating electrons create photons? is this all correct?

[Anonymous No.10432791]

>>10432643
a straight wire still creates a magnetic field

[Anonymous No.10432837]

Whether or not there is a magnetic field is determined by reference frame. Einstein Himself admitted that relativity was just a rip off of Lorentz local time.

[Anonymous No.10432846]

I just watched that 3blue1brown visualizing quaternions video again and for whatever reason I think it might be relevant. You are Linus the linelander

[Anonymous No.10432876]

>>10431999
I like to think about it like this.
A moving charged particle creates a wake like a boat moving through water.

[Anonymous No.10434491]

>>10431999

[Anonymous No.10434556]

>>10432016
this

>>10431999
it's essentially the "relativistic part of the electric field". to demonstrate this theoretically, consider two charge-neutral parallel infinite wires carrying current in 1) the same direction and 2) opposite directions, and analyze charge densities in the wires from a frame of reference moving with the currents. Taking special relativity length contraction into account, you'll find that the charge-neutral wires actually appear charged in the moving (w.r.t the wires, ie atomic nuclei) reference frame, and thus you predict an attractive electric force,

[Anonymous No.10435007]

>>10432506
>>10431999
>What's the reason on an atomic or subatomic level, what is creating that field ?

maxwell described electrical behavior mathematecaly but in this case is better to go with the father of electrical engineering charles steinmetz, from his book "Elementary Lectures on Electric Discharges, Waves and Impulses, and Other Transients":

"a condutor subject to an electric potential will produce two simultaneous and complementary fields, one magnetic concentric to the conductor and the other electrostatic (or better called dielectric) radial to the conductor"

on a atomic level the electric potential applied to the conductor basically puts all the atoms and their respective electro-magnetic fields in phase with each other creating a coherent field all through the conductor.

this is why any conductor in a high speed circuit (in other words, working at high frequencies) becomes automatically an antenna (its inherent) and this is why you have to take special precautions for high speed circuits and their design.

page 10 "the electric field":

http://www.tuks.nl/pdf/Reference_Material/Steinmetz/CP%20Steinmetz%20-%20Elementary%20Lectures%20on%20Electric%20Discharges,%20Waves%20and%20Impulses,%20and%20Other%20Transients%20-%201911.pdf

[Anonymous No.10436284]

>>10431999
IMO it's because when you run a current through a wire you are essentially "overclocking" its stable energy state by pumping it with extra electrons - more than it's used to. The wire wants so badly to transfer some of this load to achieve entropy that it actually drags other objects from the surrounding space in towards it with a field of a certain "tuning". Metals and ferromagnetic objects just happen to be "tuned" easily to this magnetism and get dragged in easier. This ability metals and ferromagnetics have to resonate and tune to external vibrations is also somewhat related to why metals are widely used as components of instruments.

Prove me wrong.

[Anonymous No.10436324]

>>10431999

>what is creating that field?

Moving charges (current). And (electro)magnetic fields create more moving charges. You can think of it as a domino or tidal effect. Moving charges cause other charges to move. The (electro)magnetic field is just an abstract mathematical expression we have created to represent that phenomenon.

I may have said something silly because it's been a while since I studied Maxwell's equations, and it's not like I ever fully understood them.

[Anonymous No.10437024]

>>10432022
You have to be patient with it.

[Anonymous No.10437168]

>>10432569
>Charged particles create electromagnetic fields
isnt it that they are perturbations in the electromagnetic field, not that they create the field?

[Anonymous No.10437212]

>>10432837
This. The magnetic and electric fields get interchanged when changing the frame of reference.

[Anonymous No.10437228]

>>10436284
>Pumping it with extra electrons
Incorrect. The only difference between a wire in which current is flowing and one where it is not is that charge carriers are moving in one and not the other.

>achieve entropy
This has no meaning. Entropy is a physical quantity not a state.

>field of a certain "tuning"
This makes no sense. How can a field have an associated "tuning"? A field isn't really a tangible thing, a field cannot resonate, it is a medium through which waves propagate.

>instruments
what is
>woodwind
>nylon strings
>percussion
>whistling
Literally all physical things have an associated resonant frequency. Metals are not special.
The reason some things don't resonate well is because they have high damping, which reduces the amplitude of their vibrations and broadens the peak resonant frequency.

[Anonymous No.10437790]

>>10437168
if that's the case it would require a pre-existing electromagnetic substrate... ahem..."ether"....ahem

apparently quantum field theory is still pretty new...we gonna have to wait a little for it to be fully understood but the resemblance to the ether theory is there, for some reason "ether" is such a taboo word in the scientific community...I don't get why, it was just an idea, an educated deduction to explain the behaviour of electromagnetism...then it was deamed the most absurd theory ever and now once again we found ourself with a new "substrate theory" with a new and improved fancy word (quantum field theory)...

[Anonymous No.10438013]

it's terrible, nobody intuitively understands electromagnetism

Maxwell man, why didn't you write something better?

[Anonymous No.10438516]

>>10432643
You actually need a changing current, if you have it any type of conductive material can generate an magnetic field.
I.E AC current through a coil

[Anonymous No.10438609]

>>10432643
>>10438516
nop, a straight wire with a potential (voltage) apply to it generates a electromagnetic field as per this >>10435007 it doesn't matter if it is AC or DC, for example all the relays used in cars work with DC current, if you would apply a AC current the relay will open and close continously at the beat of the AC frequency, with DC the magnetic field is maintain in a steady state until the voltage is stoped.

the reason that a relay uses a coil and not jus a single wire, basically, is to "concentrate" the biggest amount of electromagnetic field in a particular space.

btw there are AC relays too and they depend on particular designs to avoid the interruption of the field with AC voltage.

[Anonymous No.10438695]

>>10438516
uh, did you never make an electromagnet in 2nd grade, bro? charge in motion is enough to produce a magnetic field

[Anonymous No.10438711]

>>10438695
>charge in motion
As in not fixed, i.e. changing

[Anonymous No.10438719]

>>10438711
a charge in motion is a current, possibly a constant current