Electroweak/GUT Domain Wall by Hawking Radiation: Baryogenesis and Dark Matter from Several Hundred kg Black Holes

We examine the extent to which primordial black holes (PBHs) can constitute the observed dark matter while also giving rise to the measured matter-antimatter asymmetry and account for the observed baryon abundance through asymmetric Hawking radiation generated by a derivative coupling of curvature to the baryon-lepton current. We consider both broad and monochromatic mass spectra for this purpose. For the monochromatic spectrum we find that the correct dark matter and baryon ...

We propose to search for a new type of gravitational wave signature relevant for particle physics models with symmetries broken at vastly different energy scales. The spectrum contains a characteristic double-peak structure consisting of a sharp peak from domain walls and a smooth bump from a first order phase transition in the early Universe. We demonstrate how such a gravitational wave signal arises in a new theory unifying baryon number and color into an SU(4) gauge group ...

It is well known that the spontaneous breaking of discrete symmetries may lead to conflict with big-bang cosmology. This is due to formation of domain walls which give unacceptable contribution to the energy density of the universe. On the other hand it is expected that gravity breaks global symmetries explicitly. In this work we propose that this could provide a natural solution to the domain-wall problem.

We propose a novel mechanism of electroweak baryogenesis based on the standard model only and explaining the coincidence between the baryon and dark matter densities in the Universe, as well as the observed value of the baryon-to-photon ratio. In our scenario, large curvature fluctuations slightly below the threshold for Primordial Black Hole (PBH) formation locally reheat the plasma above the sphaleron barrier when they collapse gravitationally but without forming a black ho...

In the present article we put up for discussion the idea of there existing several versions, phases, of the vacuum, in the spirit in which we have long worked on this idea, namely the Multiple Point Criticality Principle, which also says that these different vacuum phases have the same energy density. We mention that we indeed predicted the Higgs mass to be 135 plus minus 10 GeV, which when measured turned out to be 125 GeV, using the assumption of this Multiple Point Critica...

Primordial black holes are under intense scrutiny since the detection of gravitational waves from mergers of solar-mass black holes in 2015. More recently, the development of numerical tools and the precision observational data have rekindled the effort to constrain the black hole abundance in the lower mass range, that is $M < 10^{23}$g. In particular, primordial black holes of asteroid mass $M \sim 10^{17}-10^{23}\,$g may represent 100\% of dark matter. While the microlensi...

We propose noncanonical domain walls as a new dark energy model inspired by grand unified theories (GUTs). We investigate the cosmic dynamics and discover that the domain walls act as either dark energy or dark matter at different times, depending on the velocity v in the observer's comoving frame. We find a single stable solution to the dynamics, i.e., only freezing (v = 0) noncanonical domain walls can enter the phantom zone without having to experience ghost field instabil...

In this Letter, we propose a new possible connection between dark matter relic density and baryon asymmetry of the universe. The portal between standard model sector and dark matter not only controls the relic density and detections of dark matter, but also allows the dark matter to trigger the first order electroweak phase transition. We discuss systematically possible scalar dark matter candidates, starting from a real singlet to arbitrary high representations. We show that...

In the simple Higgs-portal dark matter model with a conserved dark matter number, we show that there exists a non-topological soliton state of dark matter. This state has smaller energy per dark matter number than a free particle state and has its interior in the electroweak symmetric vacuum. It could be produced in the early universe from first-order electroweak phase transition and contribute most of dark matter. This electroweak symmetric dark matter ball is a novel macros...

From the point of view of elementary particle physics the gravitational constant $G$ is extraordinarily small. This has led to ask whether it could have decayed to its present value from an initial one commensurate with microscopical units. A mechanism that leads to such a decay is proposed herein. It is based on assuming that $G$ may take different values within regions of the universe separated by a novel kind of domain wall, a "G-wall". The idea is implemented by introduci...