We introduce and study a model designed to simultaneously shed light on the mysteries connected with Baryogenesis, Dark Matter and Dark Energy. The model describes a self-interacting complex axion field whose imaginary part, a pseudo-scalar axion, couples to the instanton density of gauge fields including the hypermagnetic field. This coupling may give rise to baryogenesis in the early universe. After tracing out the gauge and matter degrees of freedom, a non-trivial effective potential for the angular component of the axion field is obtained. It is proposed that oscillations of this component around a minimum of its effective potential can be interpreted as Dark Matter. The absolute value of the axion field rolls slowly towards $0$. At late times, it can give rise to Dark Energy.
String theory generically predicts the coupling between the Affleck-Dine field and axion field through higher-dimensional operators. We thus explore the Affleck-Dine baryogenesis on an axion background. It turns out that the axion oscillation produces an enough amount of baryon asymmetry of the Universe just after the inflation, even without a soft supersymmetry-breaking $A$-term. This baryogenesis scenario is applicable to the string axion inflation.
We propose a new scenario of baryogenesis, in which annihilation of axion domain walls generates a sizable baryon asymmetry. Successful baryogenesis is possible for a wide range of the axion mass and decay constant, $m \simeq 10^8 -10^{13}$ GeV and $f \simeq 10^{13} - 10^{16}$ GeV. Baryonic isocurvature perturbations are significantly suppressed in our model, in contrast to various spontaneous baryogenesis scenarios in the slow-roll regime. In particular, the axion domain wall baryogenesis is consistent with high-scale inflation which generates a large tensor-to-scalar ratio within the reach o…
We present a new scenario for generating the baryon asymmetry of the universe that is induced by a Nambu-Goldstone (NG) boson. The shift symmetry naturally controls the operators in the theory, while allowing the NG boson to couple to the spacetime geometry as well as to the baryons. The cosmological background thus sources a coherent motion of the NG boson, which leads to baryogenesis. Good candidates of the baryon-generating NG boson are the QCD axion and axion-like fields. In these cases the axion induces baryogenesis in the early universe, and can also serve as dark matter in the late univ…
The quantum chromodynamics axion with a decay constant near the Grand Unification (GUT) scale has an ultralight mass near a neV. We show, however, that axion-like particles with masses near the keV - PeV range with GUT-scale decay constants are also well motivated in that they naturally arise from axiverse theories with dark non-abelian gauge groups. We demonstrate that the correct dark matter abundance may be achieved by the heavy axions in these models through the misalignment mechanism in combination with a period of early matter domination from the long-lived dark glueballs of the same gau…
We introduce an axion-inflation model embedded in the Left-Right symmetric extension of the SM in which $W_R$ is coupled to the axion. This model merges three milestones of modern cosmology, i.e., inflation, cold dark matter, and baryon asymmetry. Thus, it can naturally explain the observed coincidences among cosmological parameters, i.e., $η_{B}\approx P_ζ$ and $Ω_{DM} \simeq 5~Ω_{B}$. The source of asymmetry is spontaneous CP violation in the physics of inflation, and the lightest right-handed neutrino is the cold dark matter candidate with mass $m_{N_1}\sim 1~GeV$. The introduced mechanism …
We consider a hidden-valley gauge sector, G, with strong coupling scale Lambda~TeV and CP-violating topological parameter, theta, as well as a new axion degree of freedom which adjusts theta to near zero in the current universe. If the G-sector couples to the Standard Model via weak-scale states charged under both, then in the early universe it is possible for the CP-violation due to theta (which has not yet been adjusted to zero by the hidden axion) to feed in to the SM and drive efficient baryogenesis during the electroweak (EW) phase transition, independent of the effectively small amount o…
A minimal extension of the Standard Model (SM) with a single new mass scale and providing a complete and consistent picture of particle physics and cosmology up to the Planck scale is presented. We add to the SM three right-handed SM-singlet neutrinos, a new vector-like color triplet fermion and a complex SM singlet scalar $σ$ that stabilises the Higgs potential and whose vacuum expectation value at $\sim 10^{11}$ GeV breaks lepton number and a Peccei-Quinn symmetry simultaneously. Primordial inflation is produced by a combination of $σ$ (non-minimally coupled to the scalar curvature) and the …
We here propose a mechanism that predicts, at early times, both baryon asymmetry and dark matter origin and that recovers the spontaneous baryogenesis during the reheating. Working with $U(1)$-invariant quark $Q$ and lepton $L$ effective fields, with an interacting term that couples the evolution of Universe's environment field $ψ$, we require a spontaneous symmetry breaking and get a pseudo Nambu-Goldstone boson $θ$. The pseudo Nambu-Goldstone boson speeds the Universe up during inflation, playing the role of inflaton, enabling baryogenesis to occur. Thus, in a quasi-static approximation over…
A decade ago, the first leptogenesis model based on inflation was proposed, where the complex phase of the inflaton field carries lepton number. If the inflaton field is an axion, it can couple to gravitational waves and gauge fields via. Chern-Simons invariants. Due to these couplings, birefringent gravitational and gauge primordial perturbations are created during inflation to generate a lepton asymmetry, establishing a possible connection between non-vanishing TB-parity violating polarization cross-correlations and leptogenesis. We also discuss the prospect for a subset of these models can …
Mechanisms for the generation of the matter-antimatter asymmetry and dark matter strongly depend on the reheating temperature T_R, the maximal temperature reached in the early universe. Forthcoming results from the LHC, low energy experiments, astrophysical observations and the Planck satellite will significantly constrain baryogenesis and the nature of dark matter, and thereby provide valuable information about the very early hot universe. At present, a wide range of reheating temperatures is still consistent with observations. We illustrate possible origins of matter and dark matter with fou…
We put forward a new proposal for generating the baryon asymmetry of the universe by making use of the dynamics of a $\mathrm{U}(1)$ scalar field coupled to dark matter. High dark matter densities cause the $\mathrm{U}(1)$ symmetry to break spontaneously so that the field acquires a large vacuum expectation value. The symmetry is restored when the density redshifts below a critical value, resulting in the coherent oscillation of the scalar field. A net $B-L$ number can be generated either via baryon number-conserving couplings to the standard model or through small symmetry-violating operators…
We elaborate on a toy-model of matter bounce, in which the matter content is constituted by two fermion species endowed with four fermion interaction term. We describe the curvaton mechanism that is forth generated, and then argue that one of the two fermionic species may realize baryogenesis, while the other (lighter) one is compatible with constrains on extra hot dark matter particles.
In a recent publication \cite{us}, a cosmological scenario featuring a scalar field, $φ$, that is a source for Dark Matter and Dark Energy has been proposed. In this paper, a concrete realization of that scenario is presented. As in many models of scalar-field driven Dark Energy, the effective Lagrangian of the field $φ$ contains a potential proportional to $e^{-φ/f}$. This potential is modulated in such a way that, in the absence of other matter fields, it has a local minimum at a small value of $φ$. Fluctuations of $φ$ around this minimum give rise to a gas of dark-matter particles. The fiel…
We study a scenario in which the baryon asymmetry is created through Hawking radiation from primordial black holes via a dynamically-generated chemical potential. This mechanism can also be used to generate the observed dark matter abundance, regardless of whether or not the black holes fully evaporate. In the case that evaporation ceases, the observed dark matter abundance is generically comprised of both relic black holes and an asymmetric dark matter component. We show that this two-component dark matter scenario can simultaneously account for the observed baryon asymmetry and the cosmologi…
We study the conditions for successful Affleck-Dine baryogenesis and the origin of gravitino dark matter in GMSB models. AD baryogenesis in GMSB models is ruled out by neutron star stability unless Q-balls are unstable and decay before nucleosynthesis. Unstable Q-balls can form if the messenger mass scale is larger than the flat-direction field Phi when the condensate fragments. We provide an example based on AD baryogenesis along a d = 6 flat direction for the case where m_{3/2} \approx 2 GeV, as predicted by gravitino dark matter from Q-ball decay. Using a phenomenological GMSB potential whi…
We show that both the baryon asymmetry of the Universe and the dark matter abundance can be explained within a single framework that makes use of maximally helical hypermagnetic fields produced during pseudoscalar inflation and the chiral anomaly in the Standard Model. We consider a minimal asymmetric dark matter model free from anomalies and constraints. We find that the observed baryon and the dark matter abundances are achieved for a wide range of inflationary parameters, and the dark matter mass ranges between 7-15 GeV. The novelty of our mechanism stems from the fact that the same source …
It is quite possible that the reheat temperature of the universe is extremely low close to the scale of Big Bang nucleosynthesis, i.e. $T_{R}\sim 1-10$ MeV. At such low reheat temperatures generating matter anti-matter asymmetry and synthesizing dark matter particles are challenging issues which need to be addressed within a framework of beyond the Standard Model physics. In this paper we point out that a successful cosmology can emerge naturally provided the R-parity violating interactions are responsible for the excess in baryons over anti-baryons and at the same time they can explain the lo…
We study the impact on electroweak baryogenesis from a swifter cosmological expansion induced by dark matter. We detail the experimental bounds that one can place on models that realize it, and we investigate the modifications of these bounds that result from a non-standard cosmological history. The modifications can be sizeable if the expansion rate of the Universe increases by several orders of magnitude. We illustrate the impact through the example of scalar field dark matter, which can alter the cosmological history enough to enable a strong-enough first-order phase transition in the Stand…
We consider the production of asymmetric dark matter during hidden sector baryogenesis. We consider a particular supersymmetric model where the dark matter candidate has a number density approximately equal to the baryon number density, with a mass of the same scale as the $b$, $c$ and $τ$. Both baryon asymmetry and dark matter are created at the same time in this model. We describe collider and direct detection signatures of this model.
In this brief report we consider couplings of the dark energy scalar, such as Quintessence to the neutrinos and discuss its implications in studies on the neutrino mass limits from Baryogenesis. During the evolution of the dark energy scalar, the neutrino masses vary, consequently the bounds on the neutrino masses we have here differ from those obtained before.
Affleck-Dine (AD) baryogenesis along a d=6 flat direction in gauge-mediated supersymmetry-breaking (GMSB) models can produce unstable Q-balls which naturally have field strength similar to the messenger scale. In this case a new kind of Q-ball is formed, intermediate between gravity-mediated and gauge-mediated type. We study in detail these new Q-ball solutions, showing how their properties interpolate between standard gravity-mediated and gauge-mediated Q-balls as the AD field becomes larger than the messenger scale. It is shown that E/Q for the Q-balls can be greater than the nucleon mass bu…
Low-scale supersymmetry breaking in string motivated theories implies the presence of O(100) TeV scale moduli, which generically lead to a significant modification of the history of the universe prior to Big Bang Nucleosynthesis. Such an approach implies a non-thermal origin for dark matter resulting from scalar decay, where the lightest supersymmetric particle can account for the observed dark matter relic density. We study the further effect of the decay on the baryon asymmetry of the universe, and find that this can satisfactorily address the problem of the over-production of the baryon asy…
Axions seem ubiquitous in string theories and some of them may be produced non-thermally by heavy scalar decays, contributing to dark radiation. We study various cosmological effects of photons produced from the axionic dark radiation through axion-photon conversion in the presence of primordial magnetic fields, and derive tight constraints on the combination of the axion-photon coupling and the primordial magnetic field.
We present a new mechanism for baryogenesis, which links the baryon asymmetry of the universe to the dark matter density. The mechanism arises naturally in the Pentagon model of TeV scale physics. In that context, it forces a re-evaluation of some of the assumptions of the model, and we detail the changes that are required in order to fit observations.
The appearance of scalar/moduli fields in the early universe, as motivated by string theory, naturally leads to non-thermal "moduli cosmology". Such cosmology provides a consistent framework where the generation of radiation, baryons, and dark matter can occur while maintaining successful Big Bang Nucleosynthesis and avoiding the cosmological moduli problem. We present a relatively economical construction with moduli cosmology, building on a variety of string-inspired components (e.g. supersymmetry, discrete symmetries, Green-Schwarz anomaly cancellation). We address a range of outstanding pro…
We study a mechanism through which the cosmic dark matter density can be explained simultaneously with the observed baryon asymmetry of the Universe. At the core of our proposal lie the out-of-equilibrium scattering processes of bath particles which are responsible for the production of feebly-interacting dark matter. The same processes violate $CP$, which further leads to an asymmetry between matter and antimatter being generated in the visible sector. We focus on the possibility that these interactions are described through non-renormalizable operators, which leads to both dark matter and th…
Hidden axions may be coupled to the standard model particles through a kinetic or mass mixing with QCD axion. We study a scenario in which a hidden axion constitutes a part of or the whole of dark matter and decays into photons through the mixing, explaining the 3.5 keV X-ray line signal. Interestingly, the required long lifetime of the hidden axion dark matter can be realized for the QCD axion decay constant at an intermediate scale, if the mixing is sufficiently small. In such a two component dark matter scenario, the primordial density perturbations of the hidden axion can be highly non-Gau…
We discuss the electroweak quintessence axion as a candidate for dark energy, taking into account observational as well as quantum-gravity constraints.
We study the electroweak baryogenesis in a fermionic dark matter scenario with a (pseudo)scalar being the mediator in the Higgs portal. It is discussed that the electroweak phase transition turns to be first-order after taking into account the role of the (pseudo)scalar in the thermal effective potential in our extended standard model. Imposing the relic density constraint from the WMAP/Planck and the bounds from the direct detection experiments XENON100/LUX, we show that the dark matter scenario with a scalar mediator is hardly capable of explaining the baryogenesis while the same model with …
It was recently proposed that weakly interacting massive particles (WIMP) may provide new ways of generating the observed baryon asymmetry in the early universe, as well as addressing the cosmic coincidence between dark matter and baryon abundances. This suggests a new possible connection between weak scale new particle physics and modern cosmology. This review summarizes the general ideas and simple model examples of the two recently proposed WIMP baryogenesis mechanisms: baryogenesis from WIMP dark matter annihilation during thermal freezeout, and baryogenesis from metastable WIMP decay afte…
Under general circumstances full thermal equilibrium may not be established for a long period after perturbative or non-perturbative decay of the inflaton has completed. One can instead have a distribution of particles which is in kinetic equilibrium and evolves adiabatically during this period. Number-violating reactions which are required to establish chemical equilibrium can become efficient only at much later times. We highlight some of the striking consequences of such a quasi-thermal Universe. In particular, thermal gravitino production yields {\it no bound} on the maximum temperature of…
We discuss a possible principle for detecting dark matter axions in galactic halos. If axions constitute a condensate in the Milky Way, stimulated emissions of the axions from a type of excitation in condensed matter can be detectable. We provide general mechanism for the dark matter emission, and, as a concrete example, an emission of dark matter axions from magnetic vortex strings in a type II superconductor are investigated along with possible experimental signatures.
Dark gauge sectors and axions are well-motivated in string theory. We demonstrate that if a confining gauge sector gives rise to dark glueballs that are a fraction of the dark matter, and the associated axion has a decay constant near the string scale, then this axion is ultralight and naturally realizes the fuzzy dark matter scenario with a modest tuning of a temperature ratio. Astrophysical observations constrain the size of the glueball component relative to the axionic component, while electric dipole moments constrain mixing with the QCD axion.
We show that in the presence of a chemical potential, black hole evaporation generates baryon number. If the inflaton or Ricci scalar is derivatively coupled to the B-L current, the expansion of the universe acts as a chemical potential and splits the energy levels of particles and their anti-particles. The asymmetric Hawking radiation of primordial black holes can thus be used to generate a B-L asymmetry. If dark matter is produced by the same mechanism, the coincidence between the mass density of visible and dark matter can be naturally explained.
This letter reviews the exact evolution equation for the axion effective potential with the axion scale factor f and phenomenological consequences of the flat effective potential solution are discussed. It is shown that the corresponding vacuum energy can be consistent with Dark Energy, and we compare this result to other studies relating the axion and Dark Energy.
