Related papers: High redshift signatures in the 21 cm forest due t…
Strong intergalactic shocks are a natural consequence of structure formation in the universe. These shocks are expected to deposit large fractions of their energy in relativistic electrons (xi_e~0.05 of the thermal energy according to…
Cosmic superstrings of string theory differ from conventional cosmic strings of field theory. We review how the physical and cosmological properties of the macroscopic string loops influence experimental searches for these relics from the…
If the symmetry breaking inducing the axion occurs after the inflation, the large axion isocurvature perturbations can arise due to a different axion amplitude in each causally disconnected patch. This causes the enhancement of the…
If cosmic strings are formed in the early universe, their associated loops emit gravitational waves during the whole cosmic history and contribute to the stochastic gravitational wave background at all frequencies. We provide a new estimate…
The cosmic string theory for cosmological fluctuations is a good example of healthy scientific progress in cosmology. It is a well defined physically motivated model that has been tested by cosmological observations and has been ruled out…
We present the most detailed computation to date of the 21-cm global signal and fluctuations at $z\gtrsim 500$. Our calculations include a highly precise estimate of the Wouthuysen-Field (WF) effect and the first explicit calculation of the…
When moduli roll in the early universe, all physical scales - including string tensions - simultaneously evolve. The dynamics of cosmic string loops with time-varying tension can produce cosmic string loop trackers in which most of the…
The formation of the first stars is an exciting frontier area in astronomy. Early redshifts z ~ 20 have become observationally promising as a result of a recently recognized effect of a supersonic relative velocity between the dark matter…
Cosmic strings, if they exist, source nonlinear and non-Gaussian perturbations all the way back to the time of equal matter and radiation (and earlier). Here, we compute the mass function of halos seeded by a scaling distribution of cosmic…
A new candidate source of gravitational radiation is described: the nearly-perfect harmonic series from individual loops of cosmic string. It is argued that theories with light cosmic strings give rise to a population of numerous long-lived…
Cosmic strings are topological defects possibly formed in the early Universe, which may be observable due to their gravitational effects on the cosmic microwave background radiation or gravitational wave experiments. To this effect it is…
The upcoming radio interferometer Square Kilometre Array (SKA) is expected to directly detect the redshifted 21-cm signal from the neutral hydrogen present during the Cosmic Dawn. Temperature fluctuations from X-ray heating of the neutral…
The observation of space-time variations in fundamental constants would provide strong evidence for the existence of new light degrees of freedom in the theory of Nature. Robustly constraining such scenarios requires exploiting observations…
The inspirals of supermaissive black hole binaries provide a convinced gravitational wave background in the nHz band, serving as the fiducial model of the recent gravitational wave signal reported by the PTA experiments. The uncertainties…
The redshifted 21-cm emission by neutral hydrogen offers a unique tool for mapping structure formation in the early universe in three dimensions. Here we provide the first detailed calculation of the 21-cm emission signal during and after…
Cosmic strings are potential gravitational wave (GW) sources that can be probed by pulsar timing arrays (PTAs). In this work we develop a detection algorithm for a GW burst from a cusp on a cosmic string, and apply it to Parkes PTA data. We…
Low-frequency observatories are currently being constructed with the goal of detecting redshifted 21cm emission from the epoch of reionization. These observatories will also be able to detect intensity fluctuations in the cumulative 21cm…
Cosmic string networks generate cosmological perturbations actively throughout the history of the universe. Thus, the string sourced anisotropy of the cosmic microwave background is not affected by Silk damping as much as the anisotropy…
Understanding of the signatures of cosmic string networks is limited by a large uncertainty in the sizes at which cosmic string loops form. We review cosmic string network evolution, and the gravitational signatures, with emphasis on this…
We have carried out semianalytic simulations to build redshifted 21-cm maps in the dark ages. An entropy-floor model is adopted for planting protogalaxies in simulated minihaloes. The model allocates gas quantities such as baryonic mass and…