Holographic Principle Research Articles

A new parameterized interacting holographic dark energy

We study a cosmological model based on the holographic principle that allows an interaction between dark energy and dark matter with a Hubble infrared cutoff. We adopt an agnostic point of view with respect to the form of the interaction between these dark components by using redshift parameterizations of the dark energy equation of state (DE EoS). Following this approach, we obtain an analytical expression of the Hubble parameter and we test it with four different parameterizations of the DE EoS using currently Pantheon supernovae, Cosmic Chronometers and Galaxy Clustering data sets. Our analyses show that the considered parameterizations on this agnostic proposal allow a late accelerated cosmic expansion in comparison to the results from previous works where specific forms of the interaction are employed but fail to explain this behaviour. Furthermore, we find that our proposal solves the so-called coincidence problem in Cosmology and in this direction shed some light on the problem of the Hubble tension.

A forecast of using fast radio burst observations to constrain holographic dark energy

Recently, about five hundred fast radio bursts (FRBs) detected by CHIME/FRB Project have been reported. The vast amounts of data would make FRBs a promising low-redshift cosmological probe in the forthcoming years, and thus the issue of how many FRBs are needed for precise cosmological parameter estimation in different dark energy models should be detailedly investigated. Different from the usually considered w(z)-parameterized models in the literature, in this work we investigate the holographic dark energy (HDE) model and the Ricci dark energy (RDE) model, which originate from the holographic principle of quantum gravity, using the simulated localized FRB data as a cosmological probe for the first time. We show that the Hubble constant H 0 can be constrained to about 2% precision in the HDE model with the Macquart relation of FRB by using 10000 accurately-localized FRBs combined with the current CMB data, which is similar to the precision of the SH0ES value. Using 10000 localized FRBs combined with the CMB data can achieve about 6% constraint on the dark-energy parameter c in the HDE model, which is tighter than the current BAO data combined with CMB. We also study the combination of the FRB data and another low-redshift cosmological probe, i.e. gravitational wave (GW) standard siren data, with the purpose of measuring cosmological parameters independent of CMB. Although the parameter degeneracies inherent in FRB and in GW are rather different, we find that more than 10000 FRBs are demanded to effectively improve the constraints in the holographic dark energy models.

Halo Properties in Helium Nuclei from the Perspective of Geometrical Thermodynamics (Ann. Phys. 2/2022)

Geometrical Thermodynamics A new approach to physics, as described in article number 2100278, allows Mike Parker and co-workers to correctly calculate the sizes of the 4He, 6He, and 8He nuclei ab initio from thermodynamics, with no quantum mechanics, inputting only the size of the proton. The cover image illustrates the 8He nucleus modelled as an alpha particle with its holomorphic 4-neutron halo. Black holes and the cosmic holographic principle obeying Penrose (hyperbolic) geometry are also represented here and have closely related thermodynamics.

Strongly coupled matrix theory and stochastic quantization: A new approach to holographic dualities

Stochastic quantization provides an alternate approach to the computation of quantum observables, by stochastically sampling phase space in a path integral. Furthermore, the stochastic variational method can provide analytical control over the strong coupling regime of a quantum field theory -- provided one has a decent qualitative guess at the form of certain observables at strong coupling. In the context of the holographic duality, the strong coupling regime of a Yang-Mills theory can capture gravitational dynamics. This can provide enough insight to guide a stochastic variational ansatz. We demonstrate this in the bosonic Banks-Fischler-Shenker-Susskind Matrix theory. We compute a two-point function at all values of coupling using the variational method showing agreement with lattice numerical computations and capturing the confinement-deconfinement phase transition at strong coupling. This opens up a new realm of possibilities for exploring the holographic duality and emergent geometry.

Conformal elasticity of mechanism-based metamaterials

Deformations of conventional solids are described via elasticity, a classical field theory whose form is constrained by translational and rotational symmetries. However, flexible metamaterials often contain an additional approximate symmetry due to the presence of a designer soft strain pathway. Here we show that low energy deformations of designer dilational metamaterials will be governed by a scalar field theory, conformal elasticity, in which the nonuniform, nonlinear deformations observed under generic loads correspond with the well-studied—conformal—maps. We validate this approach using experiments and finite element simulations and further show that such systems obey a holographic bulk-boundary principle, which enables an analytic method to predict and control nonuniform, nonlinear deformations. This work both presents a unique method of precise deformation control and demonstrates a general principle in which mechanisms can generate special classes of soft deformations.

Primordial perturbations and inflation in a holography inspired Gauss-Bonnet cosmology

We consider an action for gravity that, in addition to the Einstein-Hilbert term, contains a function of the Ricci scalar and the Gauss-Bonnet invariant. The specific form of the function considered is motivated by holographic cosmology. At background level the field equations imply modified Friedmann equations of the same form as those in the holographic cosmology. We calculate the cosmological perturbations and derive the corresponding power spectra assuming a general $k$-inflation. We find that the resulting power spectra differ substantially from those obtained in both holographic and standard cosmology. The estimated spectral index and tensor-to-scalar ratio are confronted with the Planck results.

Phase space holography with no strings attached

Keywords: phase space, holographic correspondence, hydrodynamics, effective metric We discuss the Wigner function representation from the novel standpoint of establishing a natural holographylike correspondence between the descriptions of a generic quantum system in the phase space (‘bulk’) picture versus its spacetime (‘boundary’) counterpart. In certain cases, the former may reduce to the gravity-like dynamics of a local metric-type variable while the latter takes on the form of some bosonized collective field hydrodynamics. This generic pseudo-holographic duality neither relies on any particular symmetry of the system in question, nor does it require any relation to some underlying ‘string theory’, thus providing a systematic way of constructing practical – as opposed to the previous ‘ad hoc’ – examples of genuine holographic duality.

Comparing Quantum Gravity Models: String Theory, Loop Quantum Gravity, and Entanglement Gravity versus SU(∞)-QGR

In a previous article we proposed a new model for quantum gravity (QGR) and cosmology, dubbed SU(∞)-QGR. One of the axioms of this model is that Hilbert spaces of the Universe and its subsystems represent the SU(∞) symmetry group. In this framework, the classical spacetime is interpreted as being the parameter space characterizing states of the SU(∞) representing Hilbert spaces. Using quantum uncertainty relations, it is shown that the parameter space—the spacetime—has a 3+1 dimensional Lorentzian geometry. Here, after a review of SU(∞)-QGR, including a demonstration that its classical limit is Einstein gravity, we compare it with several QGR proposals, including: string and M-theories, loop quantum gravity and related models, and QGR proposals inspired by the holographic principle and quantum entanglement. The purpose is to find their common and analogous features, even if they apparently seem to have different roles and interpretations. The hope is that this exercise provides a better understanding of gravity as a universal quantum force and clarifies the physical nature of the spacetime. We identify several common features among the studied models: the importance of 2D structures; the algebraic decomposition to tensor products; the special role of the SU(2) group in their formulation; the necessity of a quantum time as a relational observable. We discuss how these features can be considered as analogous in different models. We also show that they arise in SU(∞)-QGR without fine-tuning, additional assumptions, or restrictions.

Is it possible to implement a holographic equivalence principle?

In this work we study the implementation of the holographic equivalence principle which states that it is equivalent to have a central mass affecting a test particle than an event horizon. The conclusion is that the holographic equivalence principle cannot be implemented based only in the imbalance of the quantum fluctuations, in a similar way to the Casimir effect, and the constituents of the particle must be taken into account. Hence the gravitation cannot have an explanation only in terms of the spontaneous quantum fluctuations around a particle without taking into account the interactions of the constituents of the particle with their surroundings.

The holographic contributions to the sphere free energy

We study which bulk couplings contribute to the S3 free energy F( mathfrak{m} ) of three-dimensional mathcal{N} = 2 superconformal field theories with holographic duals, potentially deformed by boundary real-mass parameters m. In particular, we show that F( mathfrak{m} ) is independent of a large class of bulk couplings that include non-chiral F-terms and all D-terms. On the other hand, in general, F( mathfrak{m} ) does depend non-trivially on bulk chiral F-terms, such as prepotential interactions, and on bulk real-mass terms. These conclusions can be reached solely from properties of the AdS super-algebra, mathfrak{osp} (2|4). We also consider massive vector multiplets in AdS, which in the dual field theory correspond to long single-trace superconformal multiplets of spin zero. We provide evidence that F( mathfrak{m} ) is insensitive to the vector multiplet mass and to the interaction couplings between the massive vector multiplet and massless ones. In particular, this implies that F( mathfrak{m} ) does not contain information about scaling dimensions or OPE coefficients of single-trace long scalar mathcal{N} = 2 superconformal multiplets.

Information transfer with a twist

Holographic duals for CFTs compactified on a Riemann surface Σ with a twist are cast in the language of wedge holography. Σ starts as part of the field theory geometry in the UV and becomes part of the internal space in the IR. This allows to associate entanglement entropies with splits of the internal space in the IR geometry. Decomposing the internal space in the IR and geometrizing the corresponding subsystems separately leads to two interacting gravitational systems, similar to the intermediate holographic description in braneworld models. For Σ = T2 the setups are used to model information transfer from a black hole to a gravitating bath. This leads to Page curves with a phase structure which precisely mirrors that in braneworld models. The transition from geometric to non-geometric entropies is also discussed for Σ = S2 as a model for more general internal spaces in AdS/CFT.

Beyond Biological Aging: Table Analysis

Keeping in mind the relationship between the basal metabolic rate and the change in weight in the aging process, we propose to verify the holographic description of the same. For this we set ourselves the following objectives: Verify the correlation between total energy dissipation and energy dissipation per unit body mass, and verify the correlation between the total energy dissipation and the body mass. As a result of the data analysis, we obtained a coherent representation of our proposal. A high degree of correlation between the total energy dissipation in an organism and the basal metabolic rate/dry kg was found. Such a condition implies that the stated biological system satisfies the Holographic Principle.

55 Years of Holographic Non-Destructive Testing and Experimental Stress Analysis: Is there still Progress to be expected?

Holographic methods for non-destructive testing, shape measurement, and experimental stress analysis have shown to be versatile tools for the solution of many inspection problems. Their main advantages are the non-contact nature, the non-destructive and areal working principle, the fast response, high sensitivity, resolution and precision. In contrast to conventional optical techniques such as classical interferometry, the holographic principle of wavefront storage and reconstruction makes it possible to investigate objects with rough surfaces. Consequently, the response of various classes of products on operational or artificial load can be examined very elegantly. The paper looks back to the history of holographic metrology, honors the inventors of the main principles, discusses criteria for the selection of a proper inspection method, and shows exemplary applications. However, the main focus is on modern developments that are inspired by the rapid technological process in sensing technology and digitization, on current applications and future challenges.

Bianchi-I anisotropic universe with Barrow holographic dark energy

In this paper, we study Bianchi type-I universe in the presence of Barrow holographic dark energy and matter. Anisotropic cosmological model is explored here using the recently proposed holographic principle by Barrow where the standard Bekenstein–Hawking entropy is a special case. The holographic dark energy is employed to investigate the evolution of matter density and the dark energy density in an anisotropic Bianchi-I universe. The equation of state parameter of the dark energy is found to lie in the quintessence or in the phantom regime at the present epoch depending on the value of the new exponent and anisotropy in the universe. We found that an anisotropic universe with higher anisotropy transits to a late accelerating phase before a universe with lower anisotropy. It is also observed that the new exponent plays an important role to identify the nature of the universe.

Applications of X-Ray Holography

X-ray holography is widely used in material, biology, and industry fields due to its potential to measure the microstructure and dynamic change of objects. In this review, the principle of X-ray holography and the development of this technology in different application fields are systematically summarized and discussed. Through analyzing the advancement of X-ray sources and recording medium, the research and development direction of X-ray holography are prospected and the overview on current strategies of novel X-ray holography is presented. It is proved that X-ray holography, as a powerful nondestructive measurement method, can be applied to a wide range of objects.

PRODUCTION OF HOLOGRAMS THROUGH LASER- PLASMA INTERACTION WITH APPLICATIONS

This review paper covers extensive research on the production of holograms through laser plasma interaction. The concept involves production of plasma trails through femtosecond laser pulse and capturing them through charged coupled device. This particular paper also revolves around the procedure and principle of Touchable holography. It lays emphasis on tactile display that is the primary requirement for touchable holography and also throws light on hand tracking and applications of the same.

Programmable interactions and emergent geometry in an arrayof atom clouds.

Interactions govern the flow of information and the formation of correlations between constituents of many-body quantum systems, dictating phases of matter found in nature and forms of entanglement generated in the laboratory. Typical interactions decay with distance and thus produce a network of connectivity governed by geometry-such as the crystalline structure of a material or the trapping sites of atoms in a quantum simulator1,2. However, many envisioned applications in quantum simulation and computation require more complex coupling graphs including non-local interactions, which feature in models of information scrambling in black holes3-6 and mappings of hard optimization problems onto frustrated classical magnets7-11. Here we describe the realization of programmable non-local interactions in an array of atomic ensembles within an optical cavity, in which photons carry information between atomic spins12-19. By programming the distance dependence of the interactions, we access effective geometries for which the dimensionality, topology and metric are entirely distinct from the physical geometry of the array. As examples, we engineer an antiferromagnetic triangular ladder, a Möbius strip with sign-changing interactions and a treelike geometry inspired by concepts of quantum gravity5,20-22. The tree graph constitutes a toy model of holographic duality21,22, in which the quantum system lies on the boundary of a higher-dimensional geometry that emerges from measured correlations23. Our work provides broader prospects for simulating frustrated magnets and topological phases24, investigating quantum optimization paradigms10,11,25,26 and engineering entangled resource states for sensing and computation27,28.

Baryon asymmetry from the generalized uncertainty principle

The unexplained observed baryon asymmetry in the Universe is a long-standing problem in physics, with no satisfactory resolution so far. To explain this asymmetry, three Sakharov conditions must be met. An interaction term which couples space-time and the baryon current is considered, which satisfies the first two Sakharov conditions. Furthermore, it is shown that the Generalized Uncertainty Principle (GUP) from quantum gravity induces corrections to the Friedmann equations in cosmology, via the holographic principle. GUP also induces variations of energy and pressure density in the radiation dominated era, which satisfies the third Sakharov condition. Therefore, this construction provides a viable explanation for the observed baryon asymmetry. This also fixes the GUP parameters to α0≈104 and β0≈−108.

Nonuniqueness of scattering amplitudes at special points

We point out little discussed phenomenon in elementary quantum mechanics. In one-dimensional potential scattering problems, the scattering amplitudes are not uniquely determined at special points in parameter space. We examine a few explicit examples. We also discuss the relation with the pole-skipping phenomena recently found in holographic duality. In the holographic pole-skipping, the retarded Green's functions are not uniquely determined at imaginary Matsubara frequencies. It turns out that this universality comes from the fact that the corresponding potential scattering problem has the angular momentum potential.

The spectrum of marginally-deformed mathcal{N} = 2 CFTs with AdS4 S-fold duals of type IIB

A holographic duality was recently established between an mathcal{N} = 4 non-geometric AdS4 solution of type IIB supergravity in the so-called S-fold class, and a three- dimensional conformal field theory (CFT) defined as a limit of mathcal{N} = 4 super-Yang-Mills at an interface. Using gauged supergravity, the mathcal{N} = 2 conformal manifold (CM) of this CFT has been assessed to be two-dimensional. Here, we holographically characterise the large-N operator spectrum of the marginally-deformed CFT. We do this by, firstly, providing the algebraic structure of the complete Kaluza-Klein (KK) spectrum on the associated two-parameter family of AdS4 solutions. And, secondly, by computing the mathcal{N} = 2 super-multiplet dimensions at the first few KK levels on a lattice in the CM, using new exceptional field theory techniques. Our KK analysis also allows us to establish that, at least at large N, this mathcal{N} = 2 CM is topologically a non-compact cylindrical Riemann surface bounded on only one side.