Related papers: Mirror World versus large extra dimensions
Mirror matter has been proposed as a dark matter candidate. It has several very attractive features, including automatic stability and darkness, the ability to mimic the broad features of cold dark matter while in the linear density…
A series of dynamical anomalies in the orbits of distant trans-Neptunian objects points to a new celestial body (usually named Planet Nine) in the solar system. In this draft, we point out that a mirror planet captured from the outer solar…
Quantum gravity is known to be mostly a kind of metaphysical speculation. In this brief essay, we try to argue that, although still extremely difficult to reach, observational signatures can in fact be expected. The early universe is an…
The braneworld description of our universe entails a large extra dimension and a fundamental scale of gravity that might be lower by several orders of magnitude compared to the Planck scale. An interesting consequence of the braneworld…
The cosmological relaxation mechanism proposed in [1] allows for a dynamically generated large separation between the weak scale and a theory cutoff, using a sharp change of theory behaviour upon crossing the limit between unbroken and…
The dominance of string theory in the research landscape of quantum gravity physics (despite any direct experimental evidence) can, I think, be justified in a variety of ways. Here I focus on an argument from mathematical fertility, broadly…
Quantum-gravity effects in black holes are generally expected to be unobservable if they set in at transplanckian curvature scales. Here, we challenge this expectation. A near-critical spin parameter can serve as a lever arm that translates…
In case a mirror world with a copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, the mirror neutron ${\rm n'}$, could potentially mix and undergo ${\rm nn'}$ oscillations. The interaction of an…
Copious production of microscopic black holes is one of the least model-dependent predictions of TeV-scale gravity scenarios. We review the arguments behind this assertion and discuss opportunities to track the striking associated…
We suggest that recent neutrino puzzles that are the solar and atmospheric neutrino deficits as well as the possible neutrino oscillations reported by the LSND experiment and the possibility of massive neutrinos providing the hot component…
We consider mirrors of the spherical shape, that can expand or contract. Due to the excitation of the vacuum around, some spherical waves radiated from vibrating mirrors are encountered. Using experience from well-known literature on…
We explore a simple solution to the cosmological challenges of the original Mirror Twin Higgs (MTH) model that leads to interesting implications for experiment. We consider theories in which both the standard model and mirror neutrinos…
In the mirror world hypothesis the mirror baryonic component emerges as a possible dark matter candidate. An immediate question arises: how the mirror baryons behave and what are the differences from the more familiar dark matter candidates…
The Twin Higgs scenario stabilizes the Higgs mass through an approximate global symmetry and has remained natural in the face of increasingly stringent LHC bounds on colored top partners. Two basic structural questions in this framework…
A simple way to accommodate dark matter is to postulate the existence of a hidden sector. That is, a set of new particles and forces interacting with the known particles predominantly via gravity. In general this leads to a large set of…
We report on the possibility of detecting a submillimetre-sized extra dimension by observing gravitational waves (GWs) emitted by pointlike objects orbiting a braneworld black hole. Matter in the `visible' universe can generate a discrete…
We consider an SU(3)'_c\times SU(2)'_L\times U(1)'_Y mirror sector where the field content and dimensionless couplings are a copy of the SU(3)_c\times SU(2)_L\times U(1)_Y ordinary sector. Our model also contains three gauge-singlet…
Recently the CDMS collaboration has reported an excess of events in the signal region of a search for dark matter scattering with Silicon nuclei. Three events on an expected background of 0.4 have a significance of about 2 sigma, and it is…
There has been some speculation about the possible existence of a second photon which only couples to ordinary matter through mixing of the gauge kinetic terms. If the exotic photon is massless, then the principle phenomenological effect of…
We postulate an exact permutation symmetry acting on 10^32 Standard Model copies as the largest possible symmetry extension of the Standard Model. This setup automatically lowers the fundamental gravity cutoff down to TeV, and thus,…