Effective field theory of coupled dark energy and dark matter

In this work, I shall figure out the general structure of dark fabric matter, and the direct interactions of the celestial objects, ordinary matter, and ordinary energy with dark fabric matter and energy. Dark Fabric matter and energy is a hidden dimension of the parallel universes, visible Universe, galaxies, Atoms, molecules, ordinary matter, celestial objects, stellar systems, and Planetary systems. The Main Structure of Dark fabric matter consists of the Dark matter particles called Fabriton particles, Dark Matter Strings, and Dark Matter Webs. The dark matter particles are named fabriton particles. Fabriton means Fast actively binding reacting in total objects naturally. Fabriton is a good proposed name for dark matter particles to be recognized among subatomic particles. The mystery of Dark matter and the dark energy could be solved here entirely. Einstein and Newton built clear mathematical equations to describe the nature of gravity, after them many other people worked warmly to resolve the reality of gravity, dark matter, and dark energy. Gravity is the ripples, curvatures, gravitational waves, and tunnels that form rapidly in the structure of dark fabric matter and energy when celestial objects and ordinary matter particles pass through it directly.

We study a modified interacting dark energy (MIDE) model as a candidate to describe possible interaction between dark energy and dark matter as well as that between dark energy and baryonic matter. More specifically, we introduce a new parameter γ b to quantify the extent of interaction between dark energy and baryons. With three classes of cosmological distance observations including CMB measurements from Planck and WMAP9 results, as well as the recent direct measurements of the Hubble parameter as a function of redshift, we study the allowable values of γ c and γ b and other cosmological parameters. The constraint results obtained by using the MCMC method show: (1) The interaction term γ b quantifying the extent of interaction between baryonic matter and dark energy is nearly equal to 0, which strongly support the whole coupled dark energy scenario based on the assumption that baryons should remain uncoupled in order to allow a non-negligible coupling to dark matter. (2) At the 95.4 % confidence level, we see the energy of dark energy is slightly transferring to that of dark matter; (3) Concerning the typical value of the present energy density ratio between baryonic matter and dark matter in the universe, we obtain a positive coupling between dark energy and matter at 2σ, which indicates that dark energy is leaking energy to matter. Finally, concerning the observational density parameter ratio Ω b /Ω m derived from the gas mass fraction data (f g a s ), within the framework of the phenomenological interaction model, we observe a good compatibility between the observational constraints from f g a s and other combined data.

Dark energy and dark matter, two subjects of basic physics, have received a lot of attention in the 21st century. From the observational point of view, the interaction between dark energy and dark matter can significantly affect cosmological distances. This gives rise to the possibility of indirectly detecting such interaction through high-redshift cosmological probes. Theoretically, the introduction of interaction between dark energy and dark matter can assist in alleviating the coincidence problem of the standard cosmological model ($\Lambda$CDM model). Furthermore, this can provide a new method of studying the properties of dark matter particles. In this paper, based on the latest observations of multiple measurements of quasars (X-ray+UV quasars acting as standard candles, compact radio quasars acting as standard rulers) covering the redshift range of $0.04~<~z~<~5.1$ and baryonic acoustic oscillation between ($0.38~<~z~<~2.34$), we investigate the observational constraints on a variety of interacting dark energy models ($\gamma_d~$IDE model, $\gamma_m~$IDE model) and other cosmological models ($\Lambda$CDM model, XCDM model). The results provide us with a quantitative analysis of the possible interaction between dark energy and dark matter, as well as the possible range of the mass of dark matter particles. The joint analysis shows that: (1) Multiple measurements of quasars can provide more stringent constraints on the interacting dark energy models, which can further strengthen the potential of quasars acting as effective cosmological standard probes at higher redshifts; (2) In the framework of both $\gamma_m$IDE model and $\gamma_d$IDE model, the quasar data supports possible conversion of dark energy into dark matter at high redshift, which alleviates the coincidence problem to some extent. We also found that the interaction term is of a small value, which demonstrates the negligible interaction between dark matter and dark energy; (3) In the framework of $\Lambda$CDM model, which has shown the best consistency with quasar data, the density parameter of matter in the Universe is constrained at $\Omega_~m=0.317^{+0.007}_{-0.007}$, with the best-fit Hubble constant $H_0=68.177^{+0.497}_{-0.505}$ at 68.3% confidence level. These findings are consistent with the recent microwave background radiation (CMB) measurements from the Planck satellite; (4) If dark matter in the Universe exists in the form of scalar-field dark matter with $Z_2$ symmetry, we obtain the range of the mass of dark matter particles as $56~{\rm~GeV}\lesssim~m_S\lesssim~63~{\rm~GeV}$ or $m_S\gtrsim450~{\rm~GeV}$, based on the dark energy-dark matter coupling term from multiple measurements of quasars. Such conclusions agree well with the latest experimental results aimed at the direct detection of dark matter particles.

The paper brings a novel approach to unification of dark matter and dark energy in terms of a cosmic fluid. A model is introduced in which the cosmic fluid speed of sound squared is defined as a function of its equation of state (EoS) parameter. It is shown how logarithmic part of this function results in dynamical regimes previously not observed in cosmic fluid models. It is shown that in a particular dynamical regime the model behaves as a unification of dark matter and phantom dark energy. Further, it is shown that the model may describe dark matter - dark energy unification in which dark energy asymptotically behaves as dark energy with a constant EoS parameter larger than −1. In a specific parameter regime the unified fluid model also reproduces global expansion similar to ΛCDM model with fluid speed of sound vanishing for small scale factor values and being small, or even vanishing, for large scale factor values. Finally, it is shown how the model may be instrumental in describing the cosmic fluid dark matter-dark energy-dark matter unification. Physical constraints on model parameters yielding such transient dark energy behavior are obtained.

Brief review of recent advances in understanding dark matter and dark energy

We investigate the interaction between dark energy and dark matter in the framework of irreversible thermodynamics of open systems with matter creation/annihilation. We consider dark energy and dark matter as an interacting two-component (scalar field and ``ordinary'' dark matter) cosmological fluid in a homogeneous spatially flat and isotropic Friedmann-Robertson-Walker Universe. The thermodynamics of open systems as applied together with the gravitational field equations to the two-component cosmological fluid leads to a generalization of the elementary dark energy-dark matter interaction theory, in which the decay (creation) pressures are explicitly considered as parts of the cosmological fluid stress-energy tensor. Specific models describing coherently oscillating scalar waves, leading to a high particle production at the beginning of the oscillatory period, and models with a constant potential energy scalar field are considered. Furthermore, exact and numerical solutions of the gravitational field equations with dark energy-dark matter interactions are also obtained.

Gravitational lensing emerged as an observational field following the 1979 discovery of a doubly imaged quasar lensed by a foreground galaxy. In the 1980s and '90s dozens of other multiply imaged systems were observed, as well as time delay measurements, weak and strong lensing by galaxies and galaxy clusters, and the discovery of microlensing in our galaxy. The rapid pace of advances has continued into the new century. Lensing is currently one of best techniques for finding and mapping dark matter over a wide range of scales, and also addresses broader cosmological questions such as understanding the nature of dark energy. This focus issue of New Journal of Physics presents a snapshot of current research in some of the exciting areas of lensing. It provides an occasion to look back at the advances of the last decade and ahead to the potential of the coming years.

The dark side of the universe: from Zwicky to accelerated expansion

In Chapter 5 we already noted that it appears that a large fraction of the matter in the universe is dark (i.e. non-luminous) matter. The need to postulate such dark matter was noted as early as the 1930s by Zwicky, who observed that galaxies in the Coma cluster seemed to be moving too rapidly to be held together by the gravitational attraction of the visible matter. Obviously, we can hardly be satisfied with our picture of the universe until the nature and distribution of such vast quantities of matter has been settled. For example, an important question is whether this dark matter is in the form of new types of (stable) elementary particle, which have been roaming around since the earliest stages of the Big Bang: and if so, what are such particles, and why have we not met with them in accelerator experiments? Or, could it be that some of the dark matter is agglomerated in the form of non-luminous stellar objects made out of the same matter as ordinary stars, or as mini black holes or whatever? According to present ideas, the quark and lepton constituents of matter with which we are familiar in experiments at accelerators, produced in the numbers foreseen by the model of nucleosynthesis in the early universe described in Chapter 6, can account for only about 4% of the present energy density of the universe. Dark matter is estimated to account for some 20% of the total energy density, but the bulk of the energy density—that is, some 76%—has to be assigned to ‘dark energy’, which in Chapter 5 was identified with vacuum energy. However, the true source of the dark energy—like that of the dark matter—is unknown at present.

We have considered a cosmological model of holographic dark energy interacting with dark matter and another unknown component of dark energy of the universe. We have assumed two interaction terms Q and Q′ in order to include the scenario in which the mutual interaction between the two principal components (i.e., holographic dark energy and dark matter) of the universe leads to some loss in other forms of cosmic constituents. Our model is valid for any sign of Q and Q′. If Q<Q′, then part of the dark energy density decays into dark matter and the rest in the other unknown energy density component. But if Q>Q′, then dark matter energy receives from dark energy and from the unknown component of dark energy. Observation suggests that dark energy decays into dark matter. Here we have presented a general prescription of a cosmological model of dark energy which imposes mutual interaction between holographic dark energy, dark matter and another fluid. We have obtained the equation of state for the holographic dark energy density which is interacting with dark matter and other unknown component of dark energy. Using first law of thermodynamics, we have obtained the entropies for holographic dark energy, dark matter and other component of dark energy, when holographic dark energy interacting with two fluids (i.e., dark matter and other component of dark energy). Also we have found the entropy at the horizon when the radius (L) of the event horizon measured on the sphere of the horizon. We have investigated the GSL of thermodynamics at the present time for the universe enveloped by this horizon. Finally, it has been obtained validity of GSL which implies some bounds on deceleration parameter q.

The nature and properties of dark matter and dark energy in the universe are among the outstanding open issues of modern cosmology. Despite extensive theoretical and empirical efforts, the question “what is dark matter made of?” has not been answered satisfactorily. Candidates proposed to identify particle dark matter span over ninety orders of magnitude in mass, from ultra-light bosons, to massive black holes. Dark energy is a greater enigma. It is believed to be some kind of negative vacuum energy, responsible for driving galaxies apart in accelerated motion. In this article we take a relativistic approach in theorizing about dark matter and dark energy. Our approach is based on our recently proposed Information Relativity theory. Rather than theorizing about the identities of particle dark matter candidates, we investigate the relativistic effects on large scale celestial structures at their recession from an observer on Earth. We analyze a simplified model of the universe, in which large scale celestial bodies, like galaxies and galaxy clusters, are non-charged compact bodies that recede rectilinearly along the line-of-sight of an observer on Earth. We neglect contributions to dark matter caused by the rotation of celestial structures (e.g., the rotation of galaxies) and of their constituents (e.g., rotations of stars inside galaxies). We define the mass of dark matter as the complimentary portion of the derived relativistic mass, such that at any given recession velocity the sum of the two is equal to the Newtonian mass. The emerging picture from our analysis could be summarized as follows: 1) At any given redshift, the dark matter of a receding body exists in duality to its observable matter. 2) The dynamical interaction between the dark and the observed matter is determined by the body’s recession velocity (or redshift). 3) The observable matter mass density decreases with its recession velocity, with matter transforming to dark matter. 4) For redshifts z 0.5 the universe is dominated by dark matter. 5) Consistent with observational data, at redshift z = 0.5, the densities of matter and dark matter in the universe are predicted to be equal. 6) At redshift equaling the Golden Ratio (z ≈ 1.618), baryonic matter undergoes a quantum phase transition. The universe at higher redshifts is comprised of a dominant dark matter alongside with quantum matter. 7) Contrary to the current conjecture that dark energy is a negative vacuum energy that might interact with dark matter, comparisons of our theoretical results with observational results of ΛCDM cosmologies, and with observations of the relative densities of matter and dark energy at redshift z ≈ 0.55, allow us to conclude that dark energy is the energy carried by dark matter. 8) Application of the model to the case of rotating bodies, which will be discussed in detail in a subsequent paper, raises the intriguing possibility that the gravitational force between two bodies of mass is mediated by the entanglement of their dark matter components.

It is accepted in modern cosmology that the scalar field responsible for the inflationary stage of the early Universe is completely transformed into matter. It is assumed that the accelerated expansion is currently driven by dark energy (DE), which is likely determined by Einstein’s cosmological constant, unrelated to the scalar field responsible for inflation. We consider a cosmological model in which DE can currently have two components, one of which is Einstein’s constant ( $$\Lambda $$ ) and the other, smaller dark energy variable component DEV ( $${{\Lambda }_{V}}$$ ), is associated with the remnant of the scalar field that caused inflation after the main part of the scalar field has turned into matter. We consider only the stages of evolution of the Universe after recombination ( $$z \lesssim 1100$$ ), where dark matter (DM) is the predominant component of matter. It is assumed that the transformation of the scalar field into matter continues at the present time and is accompanied by the reverse process of the transformation of DM into a scalar field. The interconnection between DM and DEV, which leads to a linear relationship between the energy densities of these components after recombination $${{\rho }_{{{\text{DM}}}}} = \alpha {\kern 1pt} {{\rho }_{{{\text{DEV}}}}}$$ , is considered. Variants with a dependence of the coefficient $$\alpha (z)$$ on the redshift $$z$$ are also considered. One of the problems that have arisen in modern cosmology, called Hubble Tension (HT), is the discrepancy between the present values of the Hubble constant ( $${{H}_{0}}$$ ) measured from observations of the Universe at small redshifts ( $$z \lesssim 1$$ ) and the values found from fluctuations of the cosmic microwave background in the Universe at large redshifts ( $$z \approx 1100$$ ). In the model under consideration, this discrepancy can be explained by the deviation of the existing cosmological model from the conventional $$\Lambda $$ cold dark matter (CDM) model of the flat Universe by the action of the additional dark energy component DEV at the stages after recombination. Within this extended model, we consider various $$\alpha {\kern 1pt} (z)$$ functions that can eliminate the HT. To maintain the ratio of DEV and DM energy densities close to constant over the interval $$0 \leqslant z \lesssim 1100$$ , it is necessary to assume the existence of a wide spectrum of dark matter particle masses.

Determination of the nature of Dark Matter (DM) is one of the most fundamental problems of particle physics and cosmology. If DM is light enough and interacts with Standard Model particles directly or via some mediators with a strength beyond the gravitational one, it can be probed at particle accelerators or in complementary direct and indirect DM searches in non-collider experiments. In the absence of such signals at present we can prepare ourselves for its discovery and identification. Generic signature from DM produced in particles collisions is missing transverse energy, MET, originating from DM particles escaping detector. Using effective field theory approach one can show that, depending on the structure and DM spin, effective operators have different MET distributions. This provides potential to distinguish certain classes of effective field theory (EFT) operators and related spin of DM at the LHC. This observation can be directly applied to theories beyond EFT paradigm as we demonstrate for Supersymmetry and inert two Higgs doublet model (i2HDM) as two examples. At the same time direct and indirect DM searches strongly complement collider searches for DM with large masses and pointing that collider and non-collider DM searches have unique power to probe the nature of Dark Matter. We also highlight prospects of new collider signature from DM such as disappearing charge tracks which are characteristic for wide class of DM theories. Finally, we advocate the importance of the joint framework which would join efforts of HEP community and allow to effectively identify the underlying theory of DM.

In this paper, we examine dynamical friction at galactic scales within the framework of coupled dark energy (CDE). This model posits dark energy as coupled quintessence, which maintains a minimal coupling to gravity but interacts nonminimally with both dark matter and baryonic matter. Since our focus is primarily on the Newtonian regime within galaxies, we begin by deriving the Newtonian limit of the model. Subsequently, we calculate the dynamical friction force using three different approaches. We demonstrate that, in the absence of interaction between dark energy and matter, standard quintessence does not generate any dynamical friction at the galactic scale. However, the presence of interaction does cause dynamical friction. By applying the resulting analytic expressions to a real self-gravitating system, namely the Fornax galaxy, and by implementing the constraints on the free parameter of the model obtained from galactic observations, we demonstrate that the CDE model leads to significant deviations from the standard cold dark matter model at galactic scales. On the other hand, if the cosmological constraints are assumed for the free parameter, the effects of the model are expected to be negligible at the galactic level, at least in dynamical friction.

The Generalization of the Periodic Table: The 'Periodic Table' of 'Dark Matter'