CERN experiment to test for mirror world

Seven wonders of the mirror world

Nearly 50 years ago it was discovered that the fundamental particles,
such as the electron and proton, have 'left-handed' interactions -- they
do not respect mirror symmetry. This experimental fact motivates the idea
that a set of 'mirror particles' exist. The left-handedness of the ordinary
particles can then be balanced by the right-handedness of the mirror particles.
In this way mirror reflection symmetry can exist but requires something
profoundly new. It requires the existence of a completely new form of matter
called 'mirror matter'.

The mirror symmetry requires that the masses of the mirror particles
should be the same as their ordinary counterparts. However, ordinary and
mirror particles do not interact with each other by any of the known
fundamental forces except via gravity. Einstein's theory suggests that
anything with mass should couple to gravity, however the other fundamental
forces can act completely separately on the ordinary and mirror sectors.
Mirror matter should not be confused with anti-matter which has quite
different properties (in fact, some people have the unfortunate habit of
using the term 'mirror matter' when they really mean anti-matter). In anycase,
mirror matter is still hypothetical although there is a large range of astrophysical
and experimental evidence for its existence.

The evidence ranges from observations suggesting that most of the matter
in the Universe is invisible to unexpected properties of ghostly particles
called 'neutrinos'.

  • It predicts mirror matter stars which are invisible -- and there is a large
    body of evidence for such invisible
    dark matter. There is also some specific
    evidence that mirror stars have been observed from their gravitational effects
    on the bending of light (
    MACHO observations).

  • If mirror matter exists then mirror planets should also exist. In fact,
    there is remarkable evidence that these planets have actually been detected
    orbiting around nearby ordinary stars.

  • The opposite type of system, with an ordinary planet orbiting a mirror
    star, also apparently exits, but has been misidentified as an
    'isolated' planet!

  • Perhaps most remarkable of all, is the evidence that mirror matter
    not only exists in our solar system, but mirror matter asteroid or comet sized
    objects are frequently colliding with our planet. There may even be fragments
    of mirror matter at various impact sites around the world (such as the one
    Jordan), which could potentially be found. Nobody has looked!
On the microscopic level two types of forces or interactions can connect ordinary
and mirror matter. That is, by small transition forces connecting photons with
mirror photons and by small mass mixing terms between neutrinos and mirror
neutrinos. The observational consequences of these effects are actually observed:
  • The photon-mirror photon transition force implies a shorter effective lifetime
    for orthopositronium (a type of atom made from an electron and a positron)
    in vacuum experiments. A shorter lifetime is seen!

  • Neutrino-mirror neutrino mass mixing implies that each ordinary neutrino
    transforms (oscillates) into its mirror neutrino partner. Remarkably, solar,
    atmospheric and other neutrino experiments actually require the existence of
    new types of neutrinos, oscillating with the ordinary neutrinos in a way
    which is
    consistent with the mirror matter theory.

  • Any mirror matter hydrogen gas left over in our solar system would not have
    been swept out by the solar wind. Remnant mirror matter particles striking
    spacecraft would lead to a drag force slowing them down. In fact,
    precise measurements of the velocities of the
    Pioneer spacecraft indicate
    that they are indeed slowing down faster than expected due to known forces!

Too fantastic to be true?

At first, the idea seemed too fantastic to really be true, yet,
over the last few years it appears that almost every astrophysical and
experimental prediction of the theory has actually been observed by
observations and experiments: There is fascinating evidence for
mirror matter in the Universe from astronomical observations suggesting
that most of our galaxy is composed of exotic dark material called
`dark matter'. Recent particle physics experiments have revealed unexpected
properties of ghostly particles called `neutrinos' and weird matter
anti-matter atoms (orthopositronium). This unexpected behaviour is expected
if mirror matter exists. Most remarkable of all, is the evidence that our
planet is frequently bombarded by mirror matter asteroid sized objects,
causing puzzling events such as the 1908 Siberian explosion (
the Tunguska event)
which felled more than two thousand square kilometers of native forests
without leaving a single meteorite fragment behind! On a smaller scale
there are frequent puzzling impact events, with one such event
occurring recently (April 2001) in

A picture of one of the Jordan impact sites.

Further information

If mirror matter does exist, and we can dig it out of the ground then what can we use it for?
Perhaps something more profound than frictionless bearings...

Recent developments

  • Do comets go `poof': New evidence for disappearing comets
    In the book, Shadowlands-quest for mirror matter in the Universe, it was suggested
    that many comets might be made of mirror matter with a small component of ordinary
    matter. This is to explain their rapid reduction in luminosity after approaching
    the sun for the first time -- the ordinary matter evaporates leaving a dark mirror matter
    core. Very recent observations (above link) seem to provide evidence for this
    amazing (but admittedly very speculative) possibility.

  • New evidence that `isolated' planets extend deep into the planetary mass region.
    Are they really isolated or do they orbit invisible mirror stars?
    Can someone please do some Doppler shift measurements of these planets!

  • Falling ice blocks -- what is the cause/causes?
    A mirror matter comet striking the Earth would cause rapid cooling of the
    atmosphere. This is because mirror matter would absorb heat from the surrounding
    ordinary atmospheric atoms (this happens because of the photon-mirror photon interaction).
    This heat would be radiated away as mirror photons, thereby rapidly cooling the atmosphere.
    It might lead to the formation of clouds and maybe even ice blocks... (see the above
    link). Maybe it could also explain the observations suggesting the frequent impact of
    small comets
    which was suggested by Stephen Heyer.

Of course, more work needs to be done exploring these very recent ideas.
Perhaps they are a product of an over-active imagination!

Useful links

This page is maintained by Robert Foot, E-mail:

Last modified July 15, 2002