Question

Are there any magnets that have only one pole?

Answer 1

No, and if you managed to make one you'd be serious contender for a Nobel Prize.

Answer 2

How can you be so sure?

Answer 3

And why would it be so important so i would win a nobel prize?

Answer 4

What I mean is we (human beings) have never observed one and we have good theoretical reasons to think it's unlikely.

If you were able to make one, you would have changed in a radical way our understanding of one of the fundamental forces of nature. That's Nobel worthy.

Answer 5

Oh, what would an example of those theoretical reasons be?

Answer 6

And why does the magnet have such an impact on our understanding of the universe?

Answer 7

Ok, are there people trying to make a monopole magnet?

Answer 8

No magnet have only one pole.

Answer 9

Yes, there a people trying different things.

Answer 10

What is grad B = 0?

Answer 11

Maxwell's equations, which are fundamental to a huge portion of physics and which have withstood literally millions and millions of experimental verifications.

The relevant equation ( div B = 0 ) implies there are no magnetic monopoles.

Answer 12

Yeah, i saw that but what does that mean?

Answer 13

Since you don't know calculus, it's hard to describe to you exactly what this precise formulation means. But roughly it means that B is a vector field of magnetic force.
div B = 0 means that there is no net 'flow' of magnetic force outside of a closed region of space.

If there were a magnetic monopole, then there would be a net 'flow' of magnetic force outside of small sphere around the monopole. Maxwell's equation for the magnetic field says that's impossible.

Answer 14

So what you are saying is that a magnetic monopole would have a flow in one direction only? By the way, do you want me to learn basic calculus so that you can explain better?

Answer 15

Yes.

And no. Operators like div aren't basic calculus. Just recognize that there's a lot of mathematical language you need to learn to get to the bottom of a lot of these topics.

Answer 16

But i want to learn about these things...

Answer 17

Then learning calculus will help. But as TuringTest explained to you yesterday, that topics rests on the foundation of a good command of basic algebra and trigonometry. It's basically impossible to jump ahead and learn calculus without those topics and it sounded yesterday as though you hadn't yet studied trigonometry.

However, if you're really keen, get the mathematics text books from your school for the next 4 grades and begin to work through them.

Answer 18

The problem with my school is that it only goes up to 9th grade and im almost through that book already.. We dont have access to higher grade books. And as i said yesterday our school system is about 1 year behind the american system, i know that because i moved from an american school to a swedish school and my teachers wanted me to skip one grade. .

Answer 19

Is this a good place to learn? http://www.khanacademy.org/#browse

Answer 20

yes, that's not bad.

Answer 21

Awesome!

Answer 22

@JamesJ - I thought magnetic monopoles were predicted to exist in theory - its just that none have been observed yet?
see here: http://en.wikipedia.org/wiki/Magnetic_monopole

Answer 23

there is also an interesting article on them here: http://news.discovery.com/space/on-the-trail-of-magnetic-monopoles.html

Answer 24

The wikipedia article carefully states the Dirac result:

IF there exist magnetic monopoles THEN electric charge is quantized.

We have found that indeed electric charge is quantized, which suppers the idea there might be monopoles, but is not a theoretical prediction of it.

There exists also different gauge theories which support the idea of the existence of magnetic monopoles. But there's no experimental evidence to support them right now.

Answer 25

ok - so you are saying there is no theory that actually predicts that they must exist?

Answer 26

There are some gauge theories that predict the existence of monopoles, but they have no basis in observation. So I'd say there is no accepted theory in physics that predicts the existence of monopoles.

Answer 27

There are a number of theories that admit the possibility of monopoles. The proof will be if we observe one! :-)

Answer 28

ok - thk for taking the time to clarify this - your explanations really help (as always)

Answer 29

Are they theories that negate string theory?

Answer 30

Magnets can never have one pole
because the Magnetic lines always travels from the north to the south
so there is not magnet is with 1 pole
you will need 2 poles for magnetic lines travel
and for attracting magnetic materials

Answer 31

I think if you find a magnetic monopole you have probably found an unlimited source of energy.

Answer 32

I think if we find a magnetic monopole we will have found an unlimited source of energy, then we just need to learn how to convert it.