Monopoles

Monopole
Image from Steve Bowers
Magnetic Monopoles (note that the lines of force extend in three dimensions in a 'hedgehog'-like configuration

Magnetic Monopoles

Magnetic monopoles are elementary particles that carry units of magnetic charge. Monopoles are their own antiparticles: a North monopole will mutually annihilate a South monopole. Related to monopoles are dyons, which carry electric charge in addition to magnetic charge. First theorized by the pre-Information Age physicist P.A.M. Dirac, the existence of a single monopole with 68.5n*e charge (n=1,2,3,...) served to fix the value of e, the fundamental unit of electric charge, in the Universe. Monopoles have a direct connection to the topology of the cosmos. Unlike instantons, monopoles are inherently stable.

First, the Dirac string of the classical Dirac monopole is connected to topological properties of fermions (spin 1/2 particles). In particular, a fermion connected to its background by strings is entangled by a 360 degree rotation, but unentangled by a 720 degree rotation*. Next, once the Higgs boson and symmetry breaking mechanisms in classical cosmology were discovered, monopoles were found to be a 0-dimensional, or point defect in the scalar Higgs field -- the so-called "hedgehog potential". (See references below for details.) Finally, massless monopoles arise naturally in non-Abelian string theories and SU(2) supersymmetric theories.

Due to their topological nature, monopoles are naturally produced in great numbers at the beginning of the Universe via the Kibble mechanism.** Because of their unique properties, as will be seen later, monopole production rate must be constrained significantly by other factors, such as inflation of the Universe.

Properties

Monopoles are easily accelerated by strong magnetic fields. Dyons are possible (electrically and magnetically charged monopoles), but "colored" dyons (SU(3) color charge from the strong nuclear force) are not. Massive monopoles weigh up to 10E16 GeV, equivalent to an amoeba.

At strong nuclear force energy scales (e.g. fusion), the monopole core restores the symmetry of the unified gauge group, which catalyzes nucleon decay proportional to the area of the core. This is a very small number, 10E-56 cm2, and would normally be negligible; however, the s-wave (angular quantum number l=0, e.g. spherical orbital) of a fermion interacts with the monopole core to produce "s-wave sucking". S-wave sucking magnifies the ground state orbital size of the monopole, producing a cross section of unity: for example, using an SU(5) theory*** two first-order, approximate reactions are:

Monopole + neutron ---> Monopole + negative pion + positron
Monopole + proton ---> Monopole + neutral pion + positron

Natural occurrence

Phase transitions in the early universe produce topological defects corresponding to "false vacuum states" that differ from the natural vacuum expectation value of the universe. Once energy levels drop to a level below the symmetry breaking scale, these defects "freeze" in as permanent features. The defect rate is correlated with the particle horizon; this Kibble mechanism results in a constant ratio of monopoles to entropy:

n/s ~ 10^2(T/m)^3

where n = number of monopoles, s = entropy, T = phase transition temperature, m is Planck mass, and the particle horizon is assumed to be t^-1 where t is the time when the Universe was at temperature T.

For T=1014GeV, monopole mass = 1016GeV, n/s ~ 10-13.

This large ratio would produce a closed Universe ~ 1011 more massive than the currently observed one, if not for inflation.

Relic monopoles will be accelerated by galactic and intergalactic magnetic fields. The Milky Way's galactic field, for example, is 3E-6 Gauss, with a coherence length of about 300 parsecs. This will accelerate a relic monopole to a velocity of:

v~3E-3 c (10E16GeV/m)^(1/2)

where c = speed of light and m is the monopole mass in GeV

The ability of monopoles to catalyze energy release sets limits upon the primordial monopole flux, F. For example, only 10E28 monopoles in the center of the sun are required to produce the entire solar luminosity of 4E33 ergs/second.

Planets, stars, and neutron stars theoretically accumulate monopoles as follows:

A main sequence star of .6 to 30 solar masses captures monopoles of m < 10E18 GeV with velocities < 10E-3c with good efficiency. During its lifetime, a main sequence star will accumulate 10E40 * F monopoles.

Neutron stars collect monopoles most efficiently; monopoles of mass < 10E20 GeV and v < 10E-3c are captured with unit efficiency; 10E37*F monopoles in 10E10 years.

Jupiter planets stop monopoles less massive than 10E16GeV and v <10E-3. Rocky core planets such as the Earth can only stop light or slowly moving monopoles; a monopole of 10E16 GeV mass would have to be moving at v < 3E-5 c.

Civilizations looking for relic monopoles typically begin searching within the cores of gas giants. More advanced civilizations look within neutron stars.

Technology

Once a civilization builds a world-sized particle accelerator capable of probing energies in the weak symmetry-breaking regime (300GeV +), massless monopole production can begin. Massless monopoles are first used in giga-scale power plants to generate energy via monopole-catalyzed fusion. Because massless monopoles are inherently instable below the 300GeV energy scale, they must be created and used on-site.

By deep understanding and manipulation of supersymmetry at the 10E13GeV scale (i.e., temperatures of 10E27 K, nearly impossible except to archailects), or prospecting, or trade, stable massive monopoles in the 10E3 to 10E4 GeV range can be stored. This immediately opens more related technologies:

1) Portable power plants using monopole-catalyzed fusion
2) Production of magmatter
3) Advanced manipulation of electromagnetic force
4) Production of more monopoles

Technology 1) follows from the ability to store monopoles in concentrated form and use as a catalyst for power production. The term monopole-catalyzed fusion is somewhat of a misnomer: Fusion reactions are used to jump-start the plasma containing the monopoles into an energy state where monopole catalysis generates direct conversion of nuclei into mesons and photons; thereafter, the process is self-sustaining. As a second note, monopole-catalyzed fusion is more akin to fission power plants, in that runaway reactions and criticality are both features that must be controlled and guarded against.

Powerful military forces can use this technology to create compact and powerful monopole-catalysis "total conversion" bombs, which is essentially a fusion-total conversion explosive device with more controllability, lethality, and shelf-life than similar antimatter weapons. (Increased lethality comes from much lower production of muons than antimatter devices; which concentrates the energy density of the monopole bomb compared to the "fizzle" of an antimatter device. Controllability comes from doping the fusing plasma with other exotic particles to generate reactions with other side effects, such as axion or Higgs production.)

Production of magmatter initially allows materials science to dope materials with monopoles to increase its density, eventually working towards pure monopolium. In magmatter various different species of monopole known as magtrons and magnuclei form analogues of normal bayronic matter, but much smaller and much denser.Magmatter production is the key to advanced engineering using the terrific strength of these materials, and the manipulation of gravity via massive, collapsed objects.

As a source of magnetic current, monopoles can be employed to produce extremely powerful magnetic fields. These have a wide variety of technological uses. For example, magnetic monopole technology makes the Bussard ramscoop spaceflight concept practical, and greatly enhances the efficiency and compactness of fusion reactor technology. Fine-grained manipulation of strong magnetic fields finds a number of military uses, as well.

Massive monopoles can be efficiently used to produce more monopoles, without the expense and trouble of a high-energy particle accelerator. At this stage, monopoles shift from being an expensive, precious commodity to being a commonly used technology for all matter of things (computation, material science, weaponry, communication).

It is rumored that higher mass monopoles than Forward monopoles (so-called obscurely named Moravec monopoles) have been created or discovered. Although cosmic relic monopoles have yet to be discovered, and cannot be created with the current energy density of the universe, it is rumored that certain archailects are searching for them for more exotic uses.

History

Pre-Singularity Earth researchers found two candidate monopole detections, implying a much higher flux than subsequent theories provided. Some S~1 Terragens societies have managed to build massless monopole factories, by scavenging resources from derelict systems.

It is rumored that trade with the Mutual Progress Alliance caused a particular provolved clade to experiment with monopole-catalyzed fusion. To avert potential catastrophe, the clade's god gifted er Children with stable, massive monopoles. The Children were contented and used this new technology for peaceful uses for generations, until contact with one of the Caretaker Gods. Once the Children began to build self-defense weapons, eir archailect revoked er grant of monopoles. Somehow, mysteriously, every single monopole granted, and every monopole created from a granted monopole, evaporated in a burst of Hawking radiation. To this day, monopole technology remains verboten, and it is rumored that monopole weaponry is forbidden by the Compact of Eden.

Footnotes
  • A real-life example can be performed by rotating a glass of water held in the palm of the hand by 720 degrees without spilling -- the Philippine wine glass trick.
  • * The Kibble mechanism is essentially a consequence of causality -- topological defects form at the boundary between causally disconnected patches of the Universe in early cosmology. The surface of last scattering which generated the Cosmic Microwave Background consists of about 10E5 causally disconnected regions (e.g., each degree of night sky seen corresponds to a causally independent region).
  • ** SU(5) was the minimal theory coupling SU(3) strong nuclear force to the SU(2)xU(1) electroweak forces. Unfortunately, it predicted the decay of the proton in 10E31 years, and so was ruled out by observation.
 
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Development Notes
Text by Adam Getchell

Initially published on 03 October 2005.

References
Highly recommended reading; this paper is aimed at the intellectually curious, and doesn't assume a background in theoretical physics:
http://hcs.harvard.edu/~jus/0302/song.pdf

Chapter 7 used extensively in the discussion of monopole cosmology:
"The Early Universe", Kolb & Turner, ISBN 0-201-62674-8

Discusses topological defects and the Kibble mechanism:
http://www.damtp.cam.ac.uk/user/gr/public/cs_top.html

Discusses massless non-Abelian monopoles:
http://arxiv.org/PS_cache/hep-th/pdf/0407/0407272.pdf
http://arxiv.org/PS_cache/hep-th/pdf/0207/0207161.pdf

Discusses gravity waves from monopole-string systems:
http://arxiv.org/PS_cache/astro-ph/pdf/0411/0411794.pdf

Discusses monopole and domain wall formation in a "braneworld"
scenario:
http://arxiv.org/PS_cache/hep-ph/pdf/0406/0406064.pdf