Many theories predict existence of magnetic monopoles, but experiments have yet to see them

September 22, 2016 by Matthew R. Francis, Symmetry Magazine, Symmetry Magazine
It is impossible to make magnetic monopoles from a bar magnet. Credit: Wikipeida/CC0

If you chop a magnet in half, you end up with two smaller magnets. Both the original and the new magnets have "north" and "south" poles.

But what if single north and south poles exist, just like positive and negative electric charges? These hypothetical beasts, known as "magnetic monopoles," are an important prediction in several theories.

Like an electron, a magnetic monopole would be a fundamental particle. Nobody has seen one yet, but many—maybe even most—physicists would say monopoles probably exist.

"The electric and magnetic forces are exactly the same force," says Wendy Taylor of Canada's York University. "Everything would be totally symmetric if there existed a magnetic monopole. There is a strong motivation by the beauty of the symmetry to expect that this particle exists."

Dirac to the future

Combining the work of many others, nineteenth-century physicist James Clerk Maxwell showed that electricity and magnetism were two aspects of a single thing: the electromagnetic interaction.

But in Maxwell's equations, the electric and weren't quite the same. The electrical force had individual positive and negative charges. The magnetic force didn't. Without single poles—monopoles—Maxwell's theory looked asymmetrical, which bugged him. Maxwell thought and wrote a lot about the problem of the missing magnetic charge, but he left it out of the final version of his equations.

Quantum pioneer Paul Dirac picked up the monopole mantle in the early 20th century. By Dirac's time, physicists had discovered electrons and determined they were indivisible particles, carrying a fundamental unit of electric charge.

Dirac calculated the behavior of an electron in the magnetic field of a monopole. He used the rules of quantum physics, which say an electron or any particle also behaves like a wave. For an electron sitting near another particle—including a monopole—those rules say the electron's wave must go through one or more full cycles wrapping around the other particle. In other words, the wave must have at least one crest and one trough: no half crests or quarter-troughs.

For an electron in the presence of a proton, this quantum wave rule explains the colors of light emitted and absorbed by a hydrogen atom, which is made of one electron and one proton. But Dirac found the electron could only have the right wave behavior if the product of the monopole magnetic charge and the fundamental electric charge carried by an electron were a whole number. That means monopoles, like electrons, carry a fundamental, indivisible charge. Any other particle carrying the fundamental electric charge—protons, positrons, muons, and so forth—will follow the same rule.

Interestingly, the logic runs the other way too. Dirac's result says if a single type of monopole exists, even if that type is very rare, it explains a very important property of matter: why electrically charged particles carry multiples of the fundamental electric charge. (Quarks carry a fraction—one-third or two-thirds—of the fundamental charge, but they always combine to make whole-number multiples of the same charge.) And if more than one type of monopole exists, it must carry a whole-number multiple of the fundamental magnetic charge.

The magnetic unicorn

Dirac's discovery was really a plausibility argument: If monopoles existed, they would explain a lot, but nothing would crumble if they didn't.

Since Dirac's day, many theories have made predictions about the properties of magnetic monopoles. Grand unified theories predict monopoles that would be over 10 quadrillion times more massive than protons.

Producing such particles would require more energy than Earthly accelerators can reach, "but it's the energy that was certainly available at the beginning of the universe," says Laura Patrizii of the Italian National Institute for Nuclear Physics.

Cosmic ray detectors around the world are looking for signs of these monopoles, which would still be around today, interacting with molecules in the air. The MACRO experiment at Gran Sasso in Italy also looked for primordial monopoles, and provided the best constraints we have at present.

Luckily for scientists like Patrizii and Taylor, grand unified theories aren't the only ones to predict monopoles. Other theories predict magnetic monopoles of lower masses that could feasibly be created in the Large Hadron Collider, and of course Dirac's original model didn't place any mass constraints on monopoles at all. That means physicists have to be open to discovering particles that aren't part of any existing theory.

Both of them look for monopoles created at the Large Hadron Collider, Patrizii using the MoEDAL detector and Taylor using ATLAS.

"I think personally there's lots of reasons to believe that monopoles are out there, and we just have to keep looking," Taylor says.

"Magnetic monopoles are probably my favorite particle. If we discovered the , [the discovery would be] on the same scale as the Higgs particle."

Explore further: The mysterious missing magnetic monopole

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RobertKarlStonjek
5 / 5 (1) Sep 22, 2016
A static charge or voltage is possible, but for current to flow there needs to be a potential difference. Surely the same is true for magnetic flux. A static magnetic flux is only detectable when it flows, so there must be some flux potential difference at that time.

Just as a voltage can flow from, say, +10 to +8 volts, we would expect a flux between 10*North and 8*North even though there is no South Pole, though a *relative* negative voltage and relative south pole could be in evidence.
Elmo_McGillicutty
1 / 5 (4) Sep 23, 2016
All charge is self repulsive. As the charge expansion accelerates, it causes a magnetic field to grow and forces all the charge in the same perpendicular direction. At c...the magnetic turns all the expanding force into a constant rotating force. The dipole takes an axial position in the center on the spinning charge ring. The H field fountains out one side...around the ring and fountains back into the other side. A configured charge particle. M dipoles come in pairs. However....it is possible to completely enclose the H field in a circular dipole, with no external field, and therefore no poles.

axemaster
5 / 5 (3) Sep 23, 2016
Nobody has seen one yet, but many—maybe even most—physicists would say monopoles probably exist.

Really? Not my experience.

In any case, if you consider things from the perspective of the magnetic field being the relativistic electric field, it makes perfect sense for magnetic monopoles to be absent. And besides, beyond the "beauty of the math" argument, there's little motivation for the idea that magnetic monopoles should exist. Electromagnetism is complete and fully described without them.
qquax
3.3 / 5 (3) Sep 23, 2016
@axemaster, couldn't agree more. And even the "beauty of math" argument falls apart if you write down the Maxwell equations in Hestenes' geometric algebra notation, which allows to condense them into a single much more beautiful expression, by reformulating the magnetic field as bi-vector.

The magnetic monopol is a mirage that resulted from our clumsy vector calculus.
optical
Sep 24, 2016
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optical
Sep 24, 2016
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optical
Sep 24, 2016
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optical
Sep 24, 2016
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vidyunmaya
1 / 5 (4) Sep 24, 2016
Sub: cosmos Conundrums- in search of Origins
scientists seem to take another 100 years to understand cosmic vision and cosmic Function of the Universe. plasma vision of the Universe 1993 and cosmic plasma regulated eletromagnetic universe-{PREM Universe]1995 under cosmology vedas interlinks.
http://archive.or...ology.15 Books at LULU. http://www.lulu.c...jnani108
Request CERN Scientists not to mis-use Earth Stability in the name of too-high energies. like Ball Lightning mode it may boomerang before one realizes. This is a word of caution. nature has innumerable ways for corrective function.
24volts
2.3 / 5 (3) Sep 24, 2016
Monopoles don't exist and never will. Just because some mathematician thinks they do doesn't mean reality follows their silly math logic. You can make that show just about anything you want with enough effort. That doesn't mean it actually exists.
optical
Sep 25, 2016
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optical
Sep 25, 2016
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optical
Sep 25, 2016
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optical
Sep 25, 2016
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Hyperfuzzy
1 / 5 (3) Sep 25, 2016
Try using a current loop, that's what creates magnetism. The curl of E also creates a magnetic field. Have you tried it theoretically, i.e. solve for E(r,t) where there is only one pole at infinity and let that point be in you lab. juz say'n

If that's too hard, anything else is simply stupid.
optical
Sep 25, 2016
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optical
Sep 25, 2016
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optical
Sep 25, 2016
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TheGhostofOtto1923
5 / 5 (1) Sep 25, 2016
tesla observed them during his experimentings
Tesla also invented teleportation did you know it? I saw it in a movie.
https://en.wikipe...e_(film)

-Do you get your ideas from movies as well zephyr? Movies about waves perhaps?
https://youtu.be/4NyDcm8VxgQ
optical
Sep 25, 2016
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GoodElf
1.8 / 5 (5) Sep 25, 2016
Magnetic Monopoles do not exist. That is an experimental fact. "Point charges" do not exist either. All point sources are a mathematical idealization which introduce infinity into problems where integration must "cut around" to work. It is difficult to refute while there are so many aspects of current theory that rely on both such as the "cracked" Standard Model.. and "because it says so.. it must be true". Circular argument. Maxwell Theory is "happy" with the non-existence of both magnetic and electric monopoles using soliton vortices and there are source free solutions.

A sourceless photon can be considered as the source of electric and magnetic fields for example if it varies in time confined to a "circular" standing wave. See: Is the electron a photon with toroidal topology - 1997: www.cybsoc.org/electron.pdf

No such thing as a true "isolated quantum charge". Electrons and other "particles" can be separated into "parts", but like quarks.. only by so much. A bag model applies.
TheGhostofOtto1923
5 / 5 (1) Sep 26, 2016
The secret to creativity is knowing how to hide your sources -- Albert Einstein..;-) Actually most of ideas and findings required for technological singularity were invented before decades already
"Id rather be good than original." Mies van der Rohe
Magnetic Monopoles do not exist. That is an experimental fact
Please cite your source for the last experiment ever conducted.
Hyperfuzzy
not rated yet Sep 26, 2016
Where are the real scientist? Everyone seeking a proof of BS or creation of some mystery due to lack of wisdom. It won't work, magnetism is a manifestation of charge in a continuous loop. Provable theoretically and empirically. To assume differently should be allocated to fringe science, call it "nonsense!"
GoodElf
3 / 5 (4) Sep 26, 2016
@TheGhostofOtto1923:
Please cite your source for the last experiment ever conducted.
Please point to any truly successful experiment that has found a magnetic monopole. Science needs confirming experiments... there are none (so far). Therefore your counter statement is not science. Religion and superstition "work" without confirming experiments. If I said that there were fairies at the bottom of my garden, in science the onus of proof is on me to do the experiment. In your case the onus of proof is on you to show your conjecture is true since you have not stated what this "last" experiment is or it's "results". I am "pretty sure" that if any magnetic monopoles had truly been found we would all know about it.

@Hyperfuzzy:
magnetism is a manifestation of charge in a continuous loop
Not always. Heard of the Dynamic Casimir Effect? Photons are manifestations of electric and magnetic field without any charge source. The other point is photons alone can create particles.
TheGhostofOtto1923
5 / 5 (1) Sep 27, 2016
Please point to any truly successful experiment that has found a magnetic monopole. Science needs confirming experiments... there are none (so far). Therefore your counter statement is not science
So 1) you say that they havent been found so far, 2) science needs confirming experiments, and 3) continuing to look for them is not science.

You dont think very well do you? Ive often noticed this with people who use "quote" thingies a lot.
Hyperfuzzy
1 / 5 (2) Sep 27, 2016


@Hyperfuzzy: magnetism is a manifestation of charge in a continuous loop: Not always. Heard of the Dynamic Casimir Effect? Photons are manifestations of electric and magnetic field without any charge source. The other point is photons alone can create particle


OK, particles are a manifestation of the mind. They don't exist as elemental constituents of light of an EM field, it is only the continuous field. Magnetism only exist as a dynamic response to charge motion. But keep trying to capture a particle of light. When you do define its surface area, nothing more..
GoodElf
3 / 5 (2) Sep 27, 2016
@TheGhostofOtto1923: It is customary to "quote" authoritative sources because they are the ones doing the experiments. Please note the title of this "source" here is "Many theories predict existence of magnetic monopoles, but experiments have yet to see them". That inability to find Magnetic Monopoles is not for want of trying. Absence of evidence in Science is "preliminary" evidence of absence. And Science is always "preliminary". I am content to allow those who do the "hard yards" in experimental physics to have the final say about all of our flights of fancy initiated by mathematical studies or imagination. Knowledge is earned in Physics, not handed down by a G*d.

@Hyperfuzzy: There is really only "one field" from which all particles of each kind arise according to QFT, but nobody has been able to show that we can discover and measure all aspects of this Universal Field. Light can be "captured" in a Bose-Einstein Condensate and "poured" like a liquid into a container.
optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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optical
Sep 28, 2016
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Hyperfuzzy
not rated yet Sep 28, 2016
[q@optical
You are delusional, a quote without empirical evidence, or an acceptable axiomatic structure is repeating bull$hit!

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