Forums

transformer core flux propagation speed

Started by Jamie M April 13, 2012
On Tue, 17 Apr 2012 23:59:48 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>Jamie M wrote: >> >> On 4/17/2012 1:05 PM, Phil Hobbs wrote: >> > boB wrote: >> >> >> >> On Mon, 16 Apr 2012 19:10:56 -0500, "Tim Williams" >> >> <tmoranwms@gmail.com> wrote: >> >> >> >>> "boB"<K7IQ> wrote in message >> >>> news:paooo7d5m6qsglnavjs3d2q9p9agjrflue@4ax.com... >> >>>> What I mean is.... If you had a super quiet wide range hall effect >> >>>> or other magnetic sensing device in the gap of a (ferrite ?) core, >> >>>> what would be the smallest AC and/or DC signal change you >> >>>> could see ?? I know there is some noise floor in there but >> >>>> it's kind of hard to read some of the lit I've googled. >> >>> >> >>> http://en.wikipedia.org/wiki/Barkhausen_effect >> >> >> >> Looking at the B-H curve on that page, it doesn't look like >> >> particularly hard material, but it might not be magnetically >> >> "to scale" but was just a convenient curve to use for >> >> illustatration. Since I'm set up to do the test in the lab >> >> already, I will have to try it on ferrite at least while >> >> varying the DC current. It might even be worse than >> >> any other noise but I haven't noticed it yet. >> >> >> >> I wonder how much gain is needed ? Maybe a hall effect device >> >> is too noisey to eve hear this Barkhausen effect and that's one >> >> reason the wiki artilce mentions using a coil ? Looks like it could >> >> even sound like somewhat of a zipper noise. >> >> >> >> OK, so I went to the listed youtooob link and they show a guy rotating >> >> a magnet near an antenna loop looking thing. This is kinda confusing >> >> to me cuz I don't see how that is going to excercise through the B-H >> >> loop as shown in the wikipedia article.... And it's a magnet, not a >> >> soft magnetic core. Something doesn't seem quite right there. >> >> >> >> boB >> >> >> >>> >> >>> This isn't directly due to thermal noise (flipping magnetic spins, domain >> >>> fluctuations), which will be much weaker (though possibly noticable around >> >>> the Curie temperature). >> >>> >> >>> Very soft materials (low remenance) should be quieter than those with high >> >>> remenance; blatant example, applying a field to a permanent magnet won't >> >>> cause any substantial flipping until the entire coercive force is applied >> >>> (~1e5 A/m for NdFeB, IIRC), at which point the whole thing changes quite >> >>> rapidly. >> >>> >> >>> Tempted to set up an amplifier and try listening to a core. Should be able >> >>> to get a small ferrite toroid up to Curie with only the soldering iron >> >>> handy. >> >>> >> >>> Tim >> > >> > Barkhausen noise used to be a huge problem in hard disk heads, back when >> > the pole pieces were large enough to have more than one magnetic >> > domain. For the past decade or more, the domain walls have been pinned >> > by the geometry, so it's not such a big worry. >> >> Hi, >> >> Does Barkhausen noise stop above a certain frequency, maybe >> proportional to the magnetic domain sizes? Also for an extreme >> example, for AC core losses, normally they are thought of as caused by >> eddy currents, but if the frequency is (extremely!) high enough, maybe >> the eddy current losses will start reducing, but will the transformer >> core also start to lose its inductance properties so that it is not >> useful? Just curious maybe 50 years in the future core losses will not >> matter! >> > >AFAIK it isn't white, but it goes well up into the megahertz. The >spectrum depends on everything including what you had for breakfast. >(Like so many ferromagnetic things.)
I had this inspiration that amorphous magnetics, metglas, might not have Barkhausen noise, so I looked it up. They do. -- John Larkin Highland Technology, Inc jlarkin at highlandtechnology dot com http://www.highlandtechnology.com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom laser controllers Photonics and fiberoptic TTL data links VME thermocouple, LVDT, synchro acquisition and simulation
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> wrote in message 
news:pOSdnSe3x_SpZRPSnZ2dnUVZ_rCdnZ2d@supernews.com...
> No, no, Tim, you don't understand science at all. ;) Terms like > "stochastic resonance" are beautifully designed to help folks like these > > http://www.santafe.edu/research/publications/sfi-bibliography/detail/?id=126 > > extract $$ from the feds. What's more scientific than that?
I understand about half the words they use and still grok no understanding :^) Kidding, I get what they're getting at... but more to the point, I get what you're getting at :) Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms
"Robert Macy" <robert.a.macy@gmail.com> wrote in message 
news:1577f85a-b657-4fd7-97ec-ec95c4c7d97c@b14g2000vbz.googlegroups.com...
> For example, every one seems to accept that high permeability material > rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE > permeability rolls off above 1MHz because of the way the material has > been configured into the form you're using it! *IF* you can gain the > luxury of restructuring how you use the material you will see most > materials have extremely high permeability above 100MHz
Indeed, the ferrite chips I linked peak well into the GHz. That's going to be due to package L and C as much as material properties, but clearly nothing at all would happen if the ferrite itself were not also peaking out there. To be fair, the graphs of mu do include the note as to what they were measured on: a typical size toroid and the instrument. It's not obvious from the measurement how it might vary with size.
> Sadly, at around 1-2GHz magnetic material is gone due to the moment of > inertia of the magnetic molecule.
Ferrite works well into the GHz, but I don't know in that range if it's limited by materials, construction or both. All the ferrites listed for very high frequency use are low permeability, probably because the individual ferrite grains are well insulated with impurities (glass?), making a ferrite "powdered iron". At school, their standard microwave hardware included a couple watt Gunn diode, followed by an isolator. You don't want to get any diskettes close to the thing as its magnets are strong enough to hold keys on end. Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms
On 4/18/2012 5:55 AM, Robert Macy wrote:

> trigger happy google! > > Anyway, after working with metglas in the micron ranges, I've come to > the conclusion that many magnetic material data sheets are STILL > showing macro-effects. Refer to the 3C90 data sheet. The data sheet > gives information that is important to you the way you use the core > material but does NOT reflect the true basic nature of magnetic > materials. What has happened is that from reading data sheets, > engineers have gotten a mindset of how magnetism works but that > mindset is misleading both as one starts to scale smaller AND if one > tries to use that mindset's understanding to solve some kind of > performance issue. Instead of really solving a problem, you end up > optimizing a 'weak' solution. > > It's just that when you see losses and permeability roll off for a > material, much of those losses and much of that rolloff can be > attributed to conductivity and eddy currents minimizing the fields > destroying effective permeability, NOT the true nature of the > material, but rather its gross effectc because of how it's used. > Again, true these parameters are important to the designer, BECAUSE > that is the component they're working with, but do not really reflect > the nature of the basic material. > > For example, every one seems to accept that high permeability material > rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE > permeability rolls off above 1MHz because of the way the material has > been configured into the form you're using it! *IF* you can gain the > luxury of restructuring how you use the material you will see most > materials have extremely high permeability above 100MHz > > Sadly, at around 1-2GHz magnetic material is gone due to the moment of > inertia of the magnetic molecule.
Hi, Maybe these magnetic monopoles keep their moment of inertia?! http://news.bbc.co.uk/2/hi/technology/8307804.stm "magnetic monopoles that exist in special crystals known as spin ice" cheers, Jamie
On Apr 18, 11:30=A0pm, Jamie M <jmor...@shaw.ca> wrote:
> On 4/18/2012 5:55 AM, Robert Macy wrote: > > > > > > > trigger happy google! > > > Anyway, after working with metglas in the micron ranges, I've come to > > the conclusion that many magnetic material data sheets are STILL > > showing macro-effects. Refer to the 3C90 data sheet. The data sheet > > gives information that is important to you the way you use the core > > material but does NOT reflect the true basic nature of magnetic > > materials. What has happened is that from reading data sheets, > > engineers have gotten a mindset of how magnetism works but that > > mindset is misleading both as one starts to scale smaller AND if one > > tries to use that mindset's understanding to solve some kind of > > performance issue. Instead of really solving a problem, you end up > > optimizing a 'weak' solution. > > > It's just that when you see losses and permeability roll off for a > > material, much of those losses and much of that rolloff can be > > attributed to conductivity and eddy currents minimizing the fields > > destroying effective permeability, NOT the true nature of the > > material, but rather its gross effectc because of how it's used. > > Again, true these parameters are important to the designer, BECAUSE > > that is the component they're working with, but do not really reflect > > the nature of the basic material. > > > For example, every one seems to accept that high permeability material > > rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE > > permeability rolls off above 1MHz because of the way the material has > > been configured into the form you're using it! *IF* you can gain the > > luxury of restructuring how you use the material you will see most > > materials have extremely high permeability above 100MHz > > > Sadly, at around 1-2GHz magnetic material is gone due to the moment of > > inertia of the magnetic molecule. > > Hi, > > Maybe these magnetic monopoles keep their moment of inertia?! > > http://news.bbc.co.uk/2/hi/technology/8307804.stm > "magnetic monopoles that exist in special crystals known as spin ice" > > cheers, > Jamie
Embarrassingly, NEVER heard of any of this research! Thanks for the URL.
On 04/19/2012 02:30 AM, Jamie M wrote:
> On 4/18/2012 5:55 AM, Robert Macy wrote: > >> trigger happy google! >> >> Anyway, after working with metglas in the micron ranges, I've come to >> the conclusion that many magnetic material data sheets are STILL >> showing macro-effects. Refer to the 3C90 data sheet. The data sheet >> gives information that is important to you the way you use the core >> material but does NOT reflect the true basic nature of magnetic >> materials. What has happened is that from reading data sheets, >> engineers have gotten a mindset of how magnetism works but that >> mindset is misleading both as one starts to scale smaller AND if one >> tries to use that mindset's understanding to solve some kind of >> performance issue. Instead of really solving a problem, you end up >> optimizing a 'weak' solution. >> >> It's just that when you see losses and permeability roll off for a >> material, much of those losses and much of that rolloff can be >> attributed to conductivity and eddy currents minimizing the fields >> destroying effective permeability, NOT the true nature of the >> material, but rather its gross effectc because of how it's used. >> Again, true these parameters are important to the designer, BECAUSE >> that is the component they're working with, but do not really reflect >> the nature of the basic material. >> >> For example, every one seems to accept that high permeability material >> rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE >> permeability rolls off above 1MHz because of the way the material has >> been configured into the form you're using it! *IF* you can gain the >> luxury of restructuring how you use the material you will see most >> materials have extremely high permeability above 100MHz >> >> Sadly, at around 1-2GHz magnetic material is gone due to the moment of >> inertia of the magnetic molecule. > > Hi, > > Maybe these magnetic monopoles keep their moment of inertia?! > > http://news.bbc.co.uk/2/hi/technology/8307804.stm > "magnetic monopoles that exist in special crystals known as spin ice" > > cheers, > Jamie > > > >
Another grandstand play by another idiot scientist, so new? Calling those things monopoles just confuses people, but hey, why not, it brings in $$ and invited-speaker gigs. Why worry about accuracy when you can have tenure instead? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
On Apr 19, 6:41=A0am, Phil Hobbs
<pcdhSpamMeSensel...@electrooptical.net> wrote:
> On 04/19/2012 02:30 AM, Jamie M wrote: > > > > > > > On 4/18/2012 5:55 AM, Robert Macy wrote: > > >> trigger happy google! > > >> Anyway, after working with metglas in the micron ranges, I've come to > >> the conclusion that many magnetic material data sheets are STILL > >> showing macro-effects. Refer to the 3C90 data sheet. The data sheet > >> gives information that is important to you the way you use the core > >> material but does NOT reflect the true basic nature of magnetic > >> materials. What has happened is that from reading data sheets, > >> engineers have gotten a mindset of how magnetism works but that > >> mindset is misleading both as one starts to scale smaller AND if one > >> tries to use that mindset's understanding to solve some kind of > >> performance issue. Instead of really solving a problem, you end up > >> optimizing a 'weak' solution. > > >> It's just that when you see losses and permeability roll off for a > >> material, much of those losses and much of that rolloff can be > >> attributed to conductivity and eddy currents minimizing the fields > >> destroying effective permeability, NOT the true nature of the > >> material, but rather its gross effectc because of how it's used. > >> Again, true these parameters are important to the designer, BECAUSE > >> that is the component they're working with, but do not really reflect > >> the nature of the basic material. > > >> For example, every one seems to accept that high permeability material > >> rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE > >> permeability rolls off above 1MHz because of the way the material has > >> been configured into the form you're using it! *IF* you can gain the > >> luxury of restructuring how you use the material you will see most > >> materials have extremely high permeability above 100MHz > > >> Sadly, at around 1-2GHz magnetic material is gone due to the moment of > >> inertia of the magnetic molecule. > > > Hi, > > > Maybe these magnetic monopoles keep their moment of inertia?! > > >http://news.bbc.co.uk/2/hi/technology/8307804.stm > > "magnetic monopoles that exist in special crystals known as spin ice" > > > cheers, > > Jamie > > Another grandstand play by another idiot scientist, so new? =A0Calling > those things monopoles just confuses people, but hey, why not, it brings > in $$ and invited-speaker gigs. =A0Why worry about accuracy when you can > have tenure instead? > > Cheers > > Phil Hobbs > > -- > Dr Philip C D Hobbs > Principal Consultant > ElectroOptical Innovations LLC > Optics, Electro-optics, Photonics, Analog Electronics > > 160 North State Road #203 > Briarcliff Manor NY 10510 > 845-480-2058 > > hobbs at electrooptical dot nethttp://electrooptical.net
Can a true monople come into existance under ANY conceivable circumstances? For example, the suddent creation of charge particles? I mean creation, too.
Robert Macy wrote:
> > On Apr 19, 6:41 am, Phil Hobbs > <pcdhSpamMeSensel...@electrooptical.net> wrote: > > On 04/19/2012 02:30 AM, Jamie M wrote: > > > > > > > > > > > > > On 4/18/2012 5:55 AM, Robert Macy wrote: > > > > >> trigger happy google! > > > > >> Anyway, after working with metglas in the micron ranges, I've come to > > >> the conclusion that many magnetic material data sheets are STILL > > >> showing macro-effects. Refer to the 3C90 data sheet. The data sheet > > >> gives information that is important to you the way you use the core > > >> material but does NOT reflect the true basic nature of magnetic > > >> materials. What has happened is that from reading data sheets, > > >> engineers have gotten a mindset of how magnetism works but that > > >> mindset is misleading both as one starts to scale smaller AND if one > > >> tries to use that mindset's understanding to solve some kind of > > >> performance issue. Instead of really solving a problem, you end up > > >> optimizing a 'weak' solution. > > > > >> It's just that when you see losses and permeability roll off for a > > >> material, much of those losses and much of that rolloff can be > > >> attributed to conductivity and eddy currents minimizing the fields > > >> destroying effective permeability, NOT the true nature of the > > >> material, but rather its gross effectc because of how it's used. > > >> Again, true these parameters are important to the designer, BECAUSE > > >> that is the component they're working with, but do not really reflect > > >> the nature of the basic material. > > > > >> For example, every one seems to accept that high permeability material > > >> rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE > > >> permeability rolls off above 1MHz because of the way the material has > > >> been configured into the form you're using it! *IF* you can gain the > > >> luxury of restructuring how you use the material you will see most > > >> materials have extremely high permeability above 100MHz > > > > >> Sadly, at around 1-2GHz magnetic material is gone due to the moment of > > >> inertia of the magnetic molecule. > > > > > Hi, > > > > > Maybe these magnetic monopoles keep their moment of inertia?! > > > > >http://news.bbc.co.uk/2/hi/technology/8307804.stm > > > "magnetic monopoles that exist in special crystals known as spin ice" > > > > > cheers, > > > Jamie > > > > Another grandstand play by another idiot scientist, so new? Calling > > those things monopoles just confuses people, but hey, why not, it brings > > in $$ and invited-speaker gigs. Why worry about accuracy when you can > > have tenure instead? > > > > Cheers > > > > Phil Hobbs > >
> > Can a true monople come into existance under ANY conceivable > circumstances? > > For example, the suddent creation of charge particles? I mean > creation, too.
If there were really any free magnentic monopoles, they'd eat up magnetic fields the same way that free electric monopoles (e.g. electrons) eat up electric fields. You'd magnetize something, and then within a few minutes it would look as though it were demagnetized, because all its surfaces would be decorated with magnetic monopoles until the field outside went to zero. Just the way ferroelectrics behave in the real world. Martin is probably much more up on this than I am, but iirc the persistence of intergalactic magnetic fields puts some absurdly low upper limit on the cosmic abundance of magnetic monopoles. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
On Apr 19, 9:20=A0pm, Phil Hobbs
<pcdhSpamMeSensel...@electrooptical.net> wrote:
> Robert Macy wrote: > > > On Apr 19, 6:41 am, Phil Hobbs > > <pcdhSpamMeSensel...@electrooptical.net> wrote: > > > On 04/19/2012 02:30 AM, Jamie M wrote: > > > > > On 4/18/2012 5:55 AM, Robert Macy wrote: > > > > >> trigger happy google! > > > > >> Anyway, after working with metglas in the micron ranges, I've come=
to
> > > >> the conclusion that many magnetic material data sheets are STILL > > > >> showing macro-effects. Refer to the 3C90 data sheet. The data shee=
t
> > > >> gives information that is important to you the way you use the cor=
e
> > > >> material but does NOT reflect the true basic nature of magnetic > > > >> materials. What has happened is that from reading data sheets, > > > >> engineers have gotten a mindset of how magnetism works but that > > > >> mindset is misleading both as one starts to scale smaller AND if o=
ne
> > > >> tries to use that mindset's understanding to solve some kind of > > > >> performance issue. Instead of really solving a problem, you end up > > > >> optimizing a 'weak' solution. > > > > >> It's just that when you see losses and permeability roll off for a > > > >> material, much of those losses and much of that rolloff can be > > > >> attributed to conductivity and eddy currents minimizing the fields > > > >> destroying effective permeability, NOT the true nature of the > > > >> material, but rather its gross effectc because of how it's used. > > > >> Again, true these parameters are important to the designer, BECAUS=
E
> > > >> that is the component they're working with, but do not really refl=
ect
> > > >> the nature of the basic material. > > > > >> For example, every one seems to accept that high permeability mate=
rial
> > > >> rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFEC=
TIVE
> > > >> permeability rolls off above 1MHz because of the way the material =
has
> > > >> been configured into the form you're using it! *IF* you can gain t=
he
> > > >> luxury of restructuring how you use the material you will see most > > > >> materials have extremely high permeability above 100MHz > > > > >> Sadly, at around 1-2GHz magnetic material is gone due to the momen=
t of
> > > >> inertia of the magnetic molecule. > > > > > Hi, > > > > > Maybe these magnetic monopoles keep their moment of inertia?! > > > > >http://news.bbc.co.uk/2/hi/technology/8307804.stm > > > > "magnetic monopoles that exist in special crystals known as spin ic=
e"
> > > > > cheers, > > > > Jamie > > > > Another grandstand play by another idiot scientist, so new? =A0Callin=
g
> > > those things monopoles just confuses people, but hey, why not, it bri=
ngs
> > > in $$ and invited-speaker gigs. =A0Why worry about accuracy when you =
can
> > > have tenure instead? > > > > Cheers > > > > Phil Hobbs > > > Can a true monople come into existance under ANY conceivable > > circumstances? > > > For example, the suddent creation of charge particles? I mean > > creation, too. > > If there were really any free magnentic monopoles, they'd eat up > magnetic fields the same way that free electric monopoles (e.g. > electrons) eat up electric fields. =A0You'd magnetize something, and then > within a few minutes it would look as though it were demagnetized, > because all its surfaces would be decorated with magnetic monopoles > until the field outside went to zero. =A0Just the way ferroelectrics > behave in the real world. > > Martin is probably much more up on this than I am, but iirc the > persistence of intergalactic magnetic fields puts some absurdly low > upper limit on the cosmic abundance of magnetic monopoles. > > Cheers > > Phil Hobbs > > -- > Dr Philip C D Hobbs > Principal Consultant > ElectroOptical Innovations LLC > Optics, Electro-optics, Photonics, Analog Electronics > > 160 North State Road #203 > Briarcliff Manor NY 10510 > 845-480-2058 > > hobbs at electrooptical dot nethttp://electrooptical.net- Hide quoted tex=
t -
> > - Show quoted text -
I had this crazy idea (in my youth) that magnetic monopoles would obviously occur in pairs and all be bound up like hydrogen atoms. Bound up magnetic monopoles might then be dark matter... only x-rays or something can break them apart. George H.
George Herold wrote:
> > On Apr 19, 9:20 pm, Phil Hobbs > <pcdhSpamMeSensel...@electrooptical.net> wrote: > > Robert Macy wrote: > > > > > On Apr 19, 6:41 am, Phil Hobbs > > > <pcdhSpamMeSensel...@electrooptical.net> wrote: > > > > On 04/19/2012 02:30 AM, Jamie M wrote: > > > > > > > On 4/18/2012 5:55 AM, Robert Macy wrote: > > > > > > >> trigger happy google! > > > > > > >> Anyway, after working with metglas in the micron ranges, I've come to > > > > >> the conclusion that many magnetic material data sheets are STILL > > > > >> showing macro-effects. Refer to the 3C90 data sheet. The data sheet > > > > >> gives information that is important to you the way you use the core > > > > >> material but does NOT reflect the true basic nature of magnetic > > > > >> materials. What has happened is that from reading data sheets, > > > > >> engineers have gotten a mindset of how magnetism works but that > > > > >> mindset is misleading both as one starts to scale smaller AND if one > > > > >> tries to use that mindset's understanding to solve some kind of > > > > >> performance issue. Instead of really solving a problem, you end up > > > > >> optimizing a 'weak' solution. > > > > > > >> It's just that when you see losses and permeability roll off for a > > > > >> material, much of those losses and much of that rolloff can be > > > > >> attributed to conductivity and eddy currents minimizing the fields > > > > >> destroying effective permeability, NOT the true nature of the > > > > >> material, but rather its gross effectc because of how it's used. > > > > >> Again, true these parameters are important to the designer, BECAUSE > > > > >> that is the component they're working with, but do not really reflect > > > > >> the nature of the basic material. > > > > > > >> For example, every one seems to accept that high permeability material > > > > >> rolls off above some low frequency, like 1MHz, NOT TRUE. the EFFECTIVE > > > > >> permeability rolls off above 1MHz because of the way the material has > > > > >> been configured into the form you're using it! *IF* you can gain the > > > > >> luxury of restructuring how you use the material you will see most > > > > >> materials have extremely high permeability above 100MHz > > > > > > >> Sadly, at around 1-2GHz magnetic material is gone due to the moment of > > > > >> inertia of the magnetic molecule. > > > > > > > Hi, > > > > > > > Maybe these magnetic monopoles keep their moment of inertia?! > > > > > > >http://news.bbc.co.uk/2/hi/technology/8307804.stm > > > > > "magnetic monopoles that exist in special crystals known as spin ice" > > > > > > > cheers, > > > > > Jamie > > > > > > Another grandstand play by another idiot scientist, so new? Calling > > > > those things monopoles just confuses people, but hey, why not, it brings > > > > in $$ and invited-speaker gigs. Why worry about accuracy when you can > > > > have tenure instead? > > > > > > Cheers > > > > > > Phil Hobbs > > > > > Can a true monople come into existance under ANY conceivable > > > circumstances? > > > > > For example, the suddent creation of charge particles? I mean > > > creation, too. > > > > If there were really any free magnentic monopoles, they'd eat up > > magnetic fields the same way that free electric monopoles (e.g. > > electrons) eat up electric fields. You'd magnetize something, and then > > within a few minutes it would look as though it were demagnetized, > > because all its surfaces would be decorated with magnetic monopoles > > until the field outside went to zero. Just the way ferroelectrics > > behave in the real world. > > > > Martin is probably much more up on this than I am, but iirc the > > persistence of intergalactic magnetic fields puts some absurdly low > > upper limit on the cosmic abundance of magnetic monopoles. > > > > Cheers > > > > Phil Hobbs > > > > -- > > Dr Philip C D Hobbs > > Principal Consultant > > ElectroOptical Innovations LLC > > Optics, Electro-optics, Photonics, Analog Electronics > > > > 160 North State Road #203 > > Briarcliff Manor NY 10510 > > 845-480-2058 > > > > hobbs at electrooptical dot nethttp://electrooptical.net- Hide quoted text - > > > > - Show quoted text - > > I had this crazy idea (in my youth) that magnetic monopoles would > obviously occur in pairs and all be bound up like hydrogen atoms. > Bound up magnetic monopoles might then be dark matter... only x-rays > or something can break them apart. > > George H.
The Big Bang should have done a pretty good job on the intergalactic ones, then. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net