Mirror Matter Research Articles

ExplainingΩbaryon≈0.2Ωdarkthrough the synthesis of ordinary matter from mirror matter: A more general analysis

The emerging cosmological picture is of a spatially flat universe composed predominantly of three components: ordinary baryons $({\ensuremath{\Omega}}_{B}\ensuremath{\approx}0.05),$ nonbaryonic dark matter $({\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.22)$ and dark energy $({\ensuremath{\Omega}}_{\ensuremath{\Lambda}}\ensuremath{\approx}0.7).$ We recently proposed that ordinary matter was synthesized from mirror matter, motivated by the argument that the observed similarity of ${\ensuremath{\Omega}}_{B}$ and ${\ensuremath{\Omega}}_{\mathrm{dark}}$ suggests an underlying similarity between the fundamental properties of ordinary and dark matter particles. In this paper we generalize the previous analysis by considering a wider class of effective operators that nongravitationally couple the ordinary and mirror sectors. We find that while all considered operators imply ${\ensuremath{\Omega}}_{\mathrm{dark}}=\mathrm{few}\ifmmode\times\else\texttimes\fi{}{\ensuremath{\Omega}}_{B},$ only a subset quantitatively reproduce the observed ratio ${\ensuremath{\Omega}}_{B}/{\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.20.$ The $\ensuremath{\sim}1\mathrm{eV}$ mass scale induced through these operators hints at a connection with neutrino oscillation physics.

Implications of theDAMAandCRESSTexperiments for mirror matter-type dark matter

Mirror atoms are expected to be a significant component of the galactic dark matter halo if mirror matter is identified with the nonbaryonic dark matter in the Universe. Mirror matter can interact with ordinary matter via gravity and via the photon-mirror photon kinetic mixing interaction---causing mirror charged particles to couple to ordinary photons with an effective electric charge $\ensuremath{\epsilon}e.$ This means that the nuclei of mirror atoms can elastically scatter off the nuclei of ordinary atoms, leading to nuclear recoils, which can be detected in existing dark matter experiments. We show that the dark matter experiments most sensitive to this type of dark matter candidate (via the nuclear recoil signature) are the DAMA/NaI and CRESST/Sapphire experiments. Furthermore, we show that the impressive annual modulation signal obtained by the DAMA/NaI experiment can be explained by mirror matter-type dark matter for $|\ensuremath{\epsilon}|\ensuremath{\sim}5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ and is supported by DAMA's absolute rate measurement as well as the CRESST/Sapphire data. This value of $|\ensuremath{\epsilon}|$ is consistent with the value obtained from various solar system anomalies including the Pioneer spacecraft anomaly, anomalous meteorite events and lack of small craters on the asteroid Eros. It is also consistent with standard big bang nucleosynthesis.

MIRROR MATTER ADMIXTURES AND ISOSPIN BREAKING IN THE |ΔI|=1/2 RULE IN Ω- TWO BODY NONLEPTONIC DECAYS

We discuss a description of Ω- two body nonleptonic decays based on possible, albeit tiny, admixtures of mirror matter in ordinary hadrons. The |ΔI|=1/2 rule enhancement is obtained as a result of isospin symmetry and, more importantly, the rather large observed deviations from this rule result from small isospin breaking. This analysis lends support to the possibility that the enhancement phenomenon observed in low energy weak interactions may be systematically described by mirror matter admixtures in ordinary hadrons.

Have mirror micrometeorites been detected?

Slow-moving ($v \sim 15$ km/s) 'dark matter particles' have allegedly been discovered in a recent experiment. We explore the possibility that these slow moving dark matter particles are small mirror matter dust particles originating from our solar system. Ways of further testing our hypothesis, including the possibility of observing these dust particles in cryogenic detectors such as NAUTILUS, are also discussed.

Charged tensor matter fields and Lorentz symmetry violation via spontaneous symmetry breaking

We consider a model with a charged vector field along with a Cremmer-Scherk-Kalb-Ramond (CSKR) matter field coupled to a U(1) gauge potential. We obtain a natural Lorentz symmetry violation due to the local U(1) spontaneous symmetry breaking mechanism triggered by the imaginary part of the vector matter. The choice of the unitary gauge leads to the decoupling of the gauge-KR sector from the Higgs-KR sector. The excitation spectrum is carefully analyzed and the physical modes are identified. We propose an identification of the neutral massive spin-1 Higgs-like field with the massive Z' boson of the so-called mirror matter models.

Mirror dark matter and large scale structure

Mirror matter is a dark matter candidate. In this paper, we reexamine the linear regime of density perturbation growth in a universe containing mirror dark matter. Taking adiabatic scale-invariant perturbations as the input, we confirm that the resulting processed power spectrum is richer than for the more familiar cases of cold, warm and hot dark matter. The new features include a maximum at a certain scale ${\ensuremath{\lambda}}_{\mathrm{max}},$ collisional damping below a smaller characteristic scale ${\ensuremath{\lambda}}_{S}^{\ensuremath{'}},$ with oscillatory perturbations between the two. These scales are functions of the fundamental parameters of the theory. In particular, they decrease for decreasing x, the ratio of the mirror plasma temperature to that of the ordinary. For $x\ensuremath{\sim}0.2,$ the scale ${\ensuremath{\lambda}}_{\mathrm{max}}$ becomes galactic. Mirror dark matter therefore leads to bottom-up large scale structure formation, similar to conventional cold dark matter, for $x\ensuremath{\lesssim}0.2.$ Indeed, the smaller the value of x, the closer mirror dark matter resembles standard cold dark matter during the linear regime. The differences pertain to scales smaller than ${\ensuremath{\lambda}}_{S}^{\ensuremath{'}}$ in the linear regime, and generally in the nonlinear regime because mirror dark matter is chemically complex and to some extent dissipative. Lyman-\ensuremath{\alpha} forest data and the early reionization epoch established by WMAP may hold the key to distinguishing mirror dark matter from WIMP-style cold dark matter.

Was ordinary matter synthesized from mirror matter? An attempt to explain whyΩB≈0.2Ωdark

The cosmological dust has begun to settle. A likely picture is a universe comprised (predominantly) of three components: ordinary baryons $({\ensuremath{\Omega}}_{B}\ensuremath{\approx}0.05),$ nonbaryonic dark matter $({\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.22)$ and dark energy $({\ensuremath{\Omega}}_{\ensuremath{\Lambda}}\ensuremath{\approx}0.7).$ We suggest that the observed similarity of the abundances of ordinary baryons and nonbaryonic dark matter $({\ensuremath{\Omega}}_{B}/{\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.20)$ hints at an underlying similarity between the fundamental properties of ordinary and dark matter particles. This is necessarily the case if dark matter is identified with mirror matter. We examine a specific mirror matter scenario where ${\ensuremath{\Omega}}_{B}/{\ensuremath{\Omega}}_{\mathrm{dark}}\ensuremath{\approx}0.20$ is naturally obtained.

Detecting mirror matter on Earth via its thermal imprint on ordinary matter

Mirror matter type dark matter can exist on the Earth's surface, potentially in enhanced concentrations at various anomalous impact sites. Mirror matter fragments can draw in heat from the ordinary matter environment, radiate mirror photons and thereby cool the surrounding ordinary matter. We quantify this effect and suggest that it could be used to help locate mirror matter deposits. This method, together with the centrifuge technique, seems to provide the most promising means to experimentally detect mirror matter type dark matter in the Earth.

Detecting dark matter using centrifuging techniques

A new and inexpensive technique for detecting self interacting dark matter in the form of small grains in bulk matter is proposed. Depending on the interactions with ordinary matter, dark matter grains in bulk matter may be isolated by using a centrifuge and using ordinary matter as a filter. The case of mirror matter interacting with ordinary matter via photon–mirror photon kinetic mixing provides a concrete example of this type of dark matter candidate.

Mirror matter in the solar system: new evidence for mirror matter from Eros

Mirror matter is an entirely new form of matter predicted to exist if mirror symmetry is a fundamental symmetry of nature. Mirror matter has the right broad properties to explain the inferred dark matter of the Universe and might also be responsible for a variety of other puzzles in particle physics, astrophysics, meteoritics and planetary science. It is known that mirror matter can interact with ordinary matter non-gravitationally via photon-mirror photon kinetic mixing. The strength of this possibly fundamental interaction depends on the (theoretically) free parameter ϵ. We consider various proposed manifestations of mirror matter in our solar system examining in particular how the physics changes for different possible values of ϵ. We find new evidence for mirror matter in the solar system coming from the observed sharp reduction in crater rates (for craters less than about 100 m in diameter) on the asteroid 433 Eros. We also re-examine various existing ideas including the mirror matter explanation for the anomalous meteorite events, anomalous slow-down of Pioneer spacecraft etc.

C306 大気風観測のためのドップラーライダー

The multi-channel incoherent doppler lidar is currently developed under Communications Research Laboratory (CRL). This system is designed for the visualization of the stratospheric winds in clear nights. It consists of a stabilized Nd:YAG(SHG) laser, a 75cm collection mirror, Fabry-Perot interferometer and multi-ring photon detector. The preliminary observation was held at Koganei, Tokyo, and the result was compatible with the radiosonde data at Tateno/Hamamatsu between altitude 12km and 24km.

Ordinary atom–mirror-atom bound states: A new window on the mirror world

Mirror symmetry is a plausible candidate for a fundamental symmetry of particle interactions which can be exactly conserved if a set of mirror particles exist. The properties of the mirror particles seem to provide an excellent candidate to explain the inferred dark matter of the Universe and might also be responsible for a variety of other puzzles in particle physics, astrophysics, meteoritics and planetary science. One such puzzle---the orthopositronium lifetime problem---can be explained if there is a small kinetic mixing of ordinary and mirror photons. We show that this kinetic mixing implies the existence of ordinary atom--mirror-atom bound states with interesting terrestrial and astrophysical implications. We suggest that sensitive mass spectroscopic studies of ordinary samples containing heavy elements such as lead might reveal the presence of these bound states, as they would appear as anomalously heavy elements. In addition to the effects of single mirror atoms, collective effects from embedded fragments of mirror matter (such as mirror iron microparticles) are also possible. We speculate that such mirror matter fragments might explain a mysterious UV photon burst observed coming from a laser irradiated lead target in a recent experiment.

Mirror matter as self-interacting dark matter

It has been argued that the observed core density profile of galaxies is inconsistent with having a dark matter particle that is collisionless and alternative dark matter candidates which are self interacting may explain observations better. One new class of self interacting dark matter that has been proposed in the context mirror universe models of particle physics is the mirror hydrogen atom whose stability is guaranteed by the conservation of mirror baryon number. We show that the effective transport cross section for mirror hydrogen atoms, has the right order of magnitude for solving the ``cuspy'' halo problem. Furthermore, the suppression of dissipation effects for mirror atoms due to higher mirror mass scale prevents the mirror halo matter from collapsing into a disk strengthening the argument for mirror matter as galactic dark matter.

Do “isolated” planetary mass objects orbit mirror stars?

We propose that the “isolated” planetary mass objects observed by Zapatero Osorio et al. in the σ Orionis cluster might actually be in orbit around invisible stellar mass companions such as mirror stars. Mirror matter is expected to exist if parity is an unbroken symmetry of nature. Future observations can test this idea by looking for a periodic Doppler shift in the radiation emitted by the planets. The fact that the observations show an inverse dependence between the abundance of the these objects and their mass may argue in favour of the mirror matter hypothesis.

Are mirror worlds opaque?

Over the last few years, many close orbiting (∼0.05 A.U.) large mass planets (∼ M J ) of nearby stars have been discovered. Their existence has been inferred from tiny Doppler shifts in the light from the star and in one case a transit has been observed. Because ordinary planets are not expected to be able to form this close to ordinary stars due to the high temperatures, it has been speculated that the close-in large planets are in fact exotic heavenly bodies made of mirror matter. We show that the accretion of ordinary matter onto the mirror planet (from, e.g., the solar wind from the host star) should make the mirror planet opaque to ordinary radiation with an effective radius ( R p ) large enough to explain the measured size of the transiting close-in extrasolar planet, HD209458b. Furthermore, we obtain the rough prediction that R p∝ T s/M p (where T s , is the surface temperature of the ordinary matter in the mirror planet and M p is the mass of the mirror planet) which will be tested in the near future as more transiting planets are found. We also show that the mirror world interpretation of the close-in extra solar planets explains the low albedo of τ Boo b because the large estimated mass of τ Boo b (∼7 M J ) implies a small effective radius of R p ≈0.5 R J for τ Boo.

Physics of mirror photons

The physics of kinetic mixing between ordinary and mirror photons is discussed. An important role is played by four linear combinations we dub the physical photon, the sterile photon, the physical mirror photon, and the sterile mirror photon. Because of the mass degeneracy between the two gauge bosons, quantum coherence effects are important. The physical photon becomes a certain coherent superposition of the bare ordinary photon and the bare mirror photon. Similarly, the physical mirror photon is another, but not orthogonal, coherent superposition. We discuss the physics of the interaction between physical mirror photons and ordinary matter. Observational signatures for some hybrid ordinary/mirror binary astrophysical systems are qualitatively discussed. We show that a small amount of ordinary matter at the center of a mirror star may make the mirror star observable. We speculate that the recently reported halo white dwarfs might actually be mirror halo stars.

Maximal νμ– ντ oscillations, the see-saw mechanism and the Exact Parity Model

We examine one simple mechanism which leads to approximate maximal ν μ – ν τ oscillations in the standard see-saw model. In particular, we show that this scheme could be implemented in the Exact Parity Model (also known as the mirror matter model). Within this framework the solar neutrino problem is solved by maximal ν e → ν′ e oscillations (with ν′ e is the essentially sterile mirror partner of ν e ) and the LSND evidence for ν e → ν μ oscillations can also be explained.

Ultrahigh energy neutrinos from hidden-sector topological defects

We study Topological Defects (TD) in hidden (mirror) matter as possible sources of ultra-high energy neutrinos. The hidden/mirror and ordinary matter are assumed to interact very weakly through gravity or superheavy particles. An inflationary scenario is outlined in which superheavy defects are formed in hidden/mirror matter (and not in ordinary matter), and at the same time the density of mirror matter produced at the end of inflation is much smaller than that of ordinary matter. Superheavy particles produced by hidden-sector TD and the products of their decays are all sterile in our world. Only mirror neutrinos oscillate into ordinary neutrinos. We show that oscillations with maximal mixing of neutrinos from both worlds are possible and that values of $\Delta m^2$, needed for for solution of solar-neutrino and atmospheric-neutrino problems, allow the oscillation of ultra-high energy neutrinos on a timescale of the age of the Universe. A model of mass-degenerate visible and mirror neutrinos with maximal mixing is constructed. Constraints on UHE neutrino fluxes are obtained. The estimated fluxes can be 3 orders of magnitude higher than those from ordinary matter. Detection of these fluxes is briefly discussed.

Mirror dark matter and galaxy core densities

We present a particle physics realization of a recent suggestion by Spergel and Steinhardt that collisional but dissipationless dark matter may resolve the core density problem in dark-matter-dominated galaxies such as the dwarf galaxies. The realization is the asymmetric mirror universe model introduced to explain the neutrino puzzles and the microlensing anomaly. The mirror baryons are the dark matter particles with the desired properties. The time scales are right for the resolution of the core density problem and the formation of mirror stars (MACHOs observed in microlensing experiments). The mass of the region homogenized by Silk damping is between a dwarf and a large galaxy.

TeV scale quantum gravity and mirror supernovae as sources of gamma-ray bursts

Mirror matter models have been suggested recently as an explanation of neutrino puzzles and microlensing anomalies. We show that mirror supernovae can be a copious source of energetic gamma rays if one assumes that the quantum gravity scale is in the TeV range. We show that under certain assumptions plausible in the mirror models, the gamma energies could be degraded to the 10 MeV range (and perhaps even further) so as to provide an explanation of observed gamma-ray bursts. This mechanism for the origin of the gamma-ray bursts has the advantage that it neatly avoids the “baryon load problem”.