Wave Dark Matter (WaveDM) has recently gained attention as a viable candidate to account for the dark matter content of the Universe. In this paper we explore the extent to which dark matter halos in this model, and under what conditions, are able to
reproduce strong lensing systems. First, we analytically explore the lensing properties of the model -- finding that a pure WaveDM density profile, a soliton profile, produces a weaker lensing effect than other similar cored profiles. Then we analyze models with a soliton embedded in an NFW profile, as has been found in numerical simulations of structure formation. We use a benchmark model with a boson mass of $m_a=10^{-22}{rm eV}$, for which we see that there is a bi-modality in the contribution of the external NFW part of the profile, and actually some of the free parameters associated with it are not well constrained. We find that for configurations with boson masses $10^{-23}$ -- $10^{-22}{rm eV}$, a range of masses preferred by dwarf galaxy kinematics, the soliton profile alone can fit the data but its size is incompatible with the luminous extent of the lens galaxies. Likewise, boson masses of the order of $10^{-21}{rm eV}$, which would be consistent with Lyman-$alpha$ constraints and consist of more compact soliton configurations, necessarily require the NFW part in order to reproduce the observed Einstein radii. We then conclude that lens systems impose a conservative lower bound $m_a > 10^{-24}$ and that the NFW envelope around the soliton must be present to satisfy the observational requirements.
We demonstrate a scheme to generate noncoherent and coherent correlations, i.e., a tunable degree of entanglement, between degrees of freedom of a single photon. Its nature is analogous to the tuning of the purity (first-order coherence) of a single
photon forming part of a two-photon state by tailoring the correlations between the paired photons. Therefore, well-known tools such as the Clauser-Horne-Shimony-Holt (CHSH) Bell-like inequality can also be used to characterize entanglement between degrees of freedom. More specifically, CHSH inequality tests are performed, making use of the polarization and the spatial shape of a single photon. The four modes required are two polarization modes and two spatial modes with different orbital angular momentum.
An overwhelming majority of experiments in classical and quantum physics make a priori assumptions about the dimension of the system under consideration. However, would it be possible to assess the dimension of a completely unknown system only from t
he results of measurements performed on it, without any extra assumption? The concept of a dimension witness answers this question, as it allows one to bound the dimension of an unknown classical or quantum system in a device-independent manner, that is, only from the statistics of measurements performed on it. Here, we report on the experimental demonstration of dimension witnesses in a prepare and measure scenario. We use pairs of photons entangled in both polarization and orbital angular momentum to generate ensembles of classical and quantum states of dimensions up to 4. We then use a dimension witness to certify their dimensionality as well as their quantum nature. Our results open new avenues for the device-independent estimation of unknown quantum systems and for applications in quantum information science.
Gravitational waves (GWs) are expected to play a crucial role in the development of multimessenger astrophysics. The combination of GW observations with other astrophysical triggers, such as from gamma-ray and X-ray satellites, optical/radio telescop
es, and neutrino detectors allows us to decipher science that would otherwise be inaccessible. In this paper, we provide a broad review from the multimessenger perspective of the science reach offered by the third generation interferometric GW detectors and by the Einstein Telescope (ET) in particular. We focus on cosmic transients, and base our estimates on the results obtained by ETs predecessors GEO, LIGO, and Virgo.
We present a new method for dealing with geometrical selection effects in galaxy surveys while using a multifractal framework. The power of multifractal analysis lies in its connection to higher order moments, in that it not only probes clustering on
different scales but also different densities. Therefore any incompleteness issues must be correctly addressed before blindly applying this technique to real survey data.
