We revisit the evolution of cosmic acceleration in a spatially flat $$w_0w_a$$ CDM universe, in which the equation of state of dark energy takes the CPL parametrization, using the latest baryon acoustic oscillation (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI), in combination with Planck cosmic microwave background (CMB) data and several type Ia supernova datasets, including PantheonPlus, Union3, and DESY5. We analyze the deceleration parameter $\textit{q}$($\textit{z}$) and the jerk parameter $\textit{j}$($\textit{z}$) and further validate our results using the $\textit{Om}$($\textit{z}$) diagnostic. Our findings indicate significant deviations from the predictions of the $$\Lambda $$ CDM model. Specifically, DESI BAO, DESI BAO + CMB, DESI BAO + CMB + Union3, and DESI BAO + CMB + DESY5 all provide strong evidence for a slowing down of cosmic acceleration at late times, as indicated by $$j(0) < 0$$ at more than 1 $$\sigma $$ confidence level, within the framework of $$w_0w_a$$ CDM model. These results suggest that in the $$w_0w_a$$ CDM universe cosmic acceleration has already peaked and is now in a phase of decline.

China

Jincheng Wang

Hongwei Yu

Puxun Wu

Revisiting cosmic acceleration with DESI BAO

We investigate the relationship between superselection rules and quantum error correcting codes. We demonstrate that the existence of a superselection rule implies the Knill-Laflamme condition in quantum error correction. As an example, we examine the code built from quantum chromodynamics, where the proton and neutron states in the model are explored as different superselection sectors that protect logical information. Finally we comment on topological quantum error correcting codes and supersymmetric quantum field theory within this framework.

United States

Ning Bao

ChunJun Cao

Aidan Chatwin-Davies

Gong Cheng

Guanyu Zhu

Superselection rules, quantum error correction, and quantum chromodynamics

Recently, DESI has released baryon acoustic oscillation (BAO) data, and DES has also published its 5-year supernova (SN) data. These observations, combined with cosmic microwave background (CMB) data, support a dynamically evolving dark energy at a high confidence level. When using cosmological observations to weigh neutrinos, the results will be significantly affected by the measurement of dark energy due to the degeneracy between neutrino mass and the dark-energy equation of state. Therefore, we need to understand how the dynamical evolution of dark energy in the current situation will affect the measurement of neutrino mass. In this work, we utilize these latest observations and other additional distance measurements to discuss the mutual influence between neutrinos and dark energy, then calculate the Bayes factor to compare models. We consider three neutrino mass hierarchies, namely degenerate hierarchy (DH), normal hierarchy (NH), and inverted hierarchy (IH), as well as three dark energy models including $$\Lambda {\textrm{CDM}},$$ $$w{\textrm{CDM}},$$ and $$w_0w_a {\textrm{CDM}}$$ models. We find that cosmological data combined with the prior of particle physics experiments can provide strong to decisive evidence favoring the $$w_0w_a {{\textrm{CDM}}}+\sum m_\nu $$ model with NH. In the $$w_0w_a {\textrm{CDM}}$$ model, using the CMB+DESI+DESY5 data, we obtain constraints on the total neutrino mass, $$\sum m_\nu <0.171~{\textrm{eV}},\ 0.204~{\textrm{eV}},\ 0.220~{\textrm{eV}},$$ for DH, NH, and IH, respectively. Furthermore, taking into account the neutrino hierarchy or incorporating additional distance measurements results in a more pronounced deviation from the $$\Lambda $$ CDM model for dark energy. The latter, in particular, exhibits a deviation at a confidence level that surpasses $$4\sigma .$$

Guo-Hong Du

Peng-Ju Wu

Tian-Nuo Li

Xin Zhang

Impacts of dark energy on weighing neutrinos after DESI BAO

We propose a deterministic method to find all holographic entropy inequalities that have corresponding contraction maps and argue the completeness of our method. We use a triality between holographic entropy inequalities, contraction maps and partial cubes. More specifically, the validity of a holographic entropy inequality is implied by the existence of a contraction map, which we prove to be equivalent to finding an isometric embedding of a contracted graph. Thus, by virtue of the argued completeness of the contraction map proof method, the problem of finding all holographic entropy inequalities is equivalent to the problem of finding all contraction maps, which we translate to a problem of finding all image graph partial cubes. We give an algorithmic solution to this problem and characterize the complexity of our method. We also demonstrate interesting by-products, most notably, a procedure to generate candidate quantum entropy inequalities.

Keiichiro Furuya

Joydeep Naskar

Towards a complete classification of holographic entropy inequalities

We establish an equivalence between non-isometry of quantum codes and state dependence of operator reconstruction, and discuss implications of this equivalence for holographic duality. Specifically, we define quantitative measures of non-isometry and state dependence and describe bounds relating these quantities. In the context of holography we show that, assuming known gravitational path integral results for overlaps between semiclassical states, non-isometric bulk-to-boundary maps with a trivial kernel are approximately isometric and bulk reconstruction approximately state-independent. In contrast, non-isometric maps with a non-empty kernel always lead to state-dependent reconstruction. We also show that if a global bulk-to-boundary map is non-isometric, then there exists a region in the bulk which is causally disconnected from the boundary. Finally, we conjecture that, under certain physical assumptions for the definition of the Hilbert space of effective field theory in AdS space, the presence of a global horizon implies a non-isometric global bulk-to-boundary map.

Stefano Antonini

United Kingdom

Belgium

Vijay Balasubramanian

Wissam Chemissany

Non-isometry, state dependence and holography

In this work, we propose to utilize the observed ratio of spherically-averaged distance to the sound horizon scale from Baryon Acoustic Oscillation (BAO) data to test the cosmic distance duality relation (CDDR) by comparing the luminosity distances (LDs) obtained from Type Ia supernovae (SNIa) observations with angular diameter distances (ADDs) derived from these ratio measurements, using a cosmological-model-independent method. To match the LDs with the ADDs at the identical redshifts, we employ two methods: a compressed form of the Pantheon sample and a hybrid approach that combines the binning method with an artificial neural network (ANN). The Hubble parameter ( ) at any redshift is reconstructed from the observed Hubble parameter data with the ANN to derive the ADD. To avoid potential biases resulted from the specific prior values of the absolute magnitude $$M_{\textrm{B}}$$ of SNIa and the sound horizon scale $$r_{\textrm{d}}$$ from BAO measurements, we introduce the fiducial parameter $$\kappa \equiv 10^{M_{\textrm{B}} \over 5}\, r_{\textrm{d}}^{3 \over 2} $$ and marginalize their impacts by treating them as nuisance parameters with flat prior distributions in our statistical analysis. Subsequently, we update the measurements of ratio of the transverse comoving distance to the sound horizon scale from the latest BAO data released by the Dark Energy Spectroscopic Instrument (DESI) collaboration for CDDR testing. Our results indicate that BAO observation provides a powerful tool for testing the CDDR, independent of both the absolute magnitude $$M_{\textrm{B}}$$ and sound horizon scale $$r_{\textrm{d}}$$ , as well as any cosmological model.

Fan Yang

Xiangyun Fu

Bing Xu

Kaituo Zhang

Yang Huang

Ying Yang

Testing the cosmic distance duality relation using Type Ia supernovae and BAO observations

We study various notions of ‘subregion duality’ in the context of AdS/CFT. We highlight the differences between the ‘background wedge’ and the ‘operator reconstruction wedges,’ providing a resolution to the paradox raised in [1]. Additionally, we elucidate the distinctions between four different ‘operator reconstruction wedges’ and demonstrate how to enhance the proof for the absence of global symmetries in geometrical states in AdS/CFT [2, 3] as an example of these distinctions.

Yikun Jiang

Subregion duality, wedge classification and no global symmetries in AdS/CFT

We conjecture a multi-parameter generalization of the toric inequalities of [1]. We then extend their proof methods for the generalized toric inequalities in two ways. The first extension constructs the graph corresponding to the toric inequalities and the generalized toric conjectures by tiling the Euclidean space. An entanglement wedge nesting relation then determines the geometric structure of the tiles. In the second extension, we exploit the cyclic nature of the inequalities and conjectures to construct cycle graphs. Then, the graph can be obtained using graph Cartesian products of cycle graphs. In addition, we define a set of knots on the graph by following [1]. These graphs with knots then imply the validity of their associated inequality. We study the case where the graph can be decomposed into disjoint unions of torii. Under the specific case, we explore and prove the conjectures for some ranges of parameters. We also discuss ways to explore the conjectured inequalities whose corresponding geometries are d-dimensional torii (d &gt; 2).

A framework for generalizing toric inequalities for holographic entanglement entropy

Several studies in the literature have found a disagreement between compressed data on Baryon Acoustic Oscillations (BAO) derived using two distinct methodologies: the two-dimensional (2D, transverse or angular) BAO, which extracts the BAO signal from the analysis of the angular two-point correlation function; and the three-dimensional (3D or anisotropic) BAO, which also exploits the radial clustering signal imprinted on the large-scale structure of the universe. This discrepancy is worrisome, since many of the points contained in these data sets are obtained from the same parent catalogs of tracers and, therefore, we would expect them to be consistent. Since BAO measurements play a pivotal role in the building of the inverse distance ladder, this mismatch impacts the discourse on the Hubble tension and the study of theoretical solutions to the latter. So far, the discrepancy between 2D and 3D BAO has been only pointed out in the context of fitting analyses of cosmological models or parametrizations that, in practice, involve the choice of a concrete calibration of the comoving sound horizon at the baryon-drag epoch. In this Letter, for the first time, we quantify the tension in a much cleaner way, with the aid of apparent magnitudes of supernovae of Type Ia (SNIa) and excluding the radial component of the 3D BAO. We avoid the use of any calibration and cosmological model in the process. At this point we assume that the Etherington (a.k.a distance duality) relation holds. We use state-of-the-art measurements in our analysis, and study how the results change when the angular components of the 3D BAO data from BOSS/eBOSS are substituted by the recent data from DESI Y1. We find the tension to exist at the level of <math><mo>∼</mo><mn>2</mn><mi>σ</mi></math> and <math><mo>∼</mo><mn>2.5</mn><mi>σ</mi></math>, respectively, when the SNIa of the Pantheon+ compilation are used, and at <math><mo>∼</mo><mn>4.6</mn><mi>σ</mi></math> when the latter are replaced with those of DES Y5. In view of these results, we then apply a calibrator-independent method to investigate the robustness of the distance duality relation when analyzed not only with 3D BAO measurements, but also with 2D BAO. This is a test of fundamental physics, which covers, among other aspects, variations of the speed of light with the cosmic expansion or possible interactions between the dark and electromagnetic sectors. We do not find any significant hint for a violation of the cosmic distance duality relation in any of the considered data sets.

Italy

Spain

Arianna Favale

Adrià Gómez-Valent

Marina Migliaccio

Quantification of 2D vs 3D BAO tension using SNIa as a redshift interpolator and test of the Etherington relation

In this work, we test the cosmic distance duality relation (CDDR) by comparing the angular diameter distance (ADD) derived from the transverse Baryon Acoustic Oscillations (BAO) data with the luminosity distance (LD) from the Pantheon type Ia supernova (SNIa) sample. The binning method and Gaussian process are employed to match ADD data with LD data at the same redshift. First, we use nonparametric and parametric methods to investigate the impact of the specific prior values of the absolute magnitude  $$M_\textrm{B}$$  <math> <msub> <mi>M</mi> <mtext>B</mtext> </msub> </math>   from SNIa observations and the sound horizon scale  $$r_\textrm{s}$$  <math> <msub> <mi>r</mi> <mtext>s</mtext> </msub> </math>   from transverse BAO measurements on the CDDR tests. The results obtained from the parametric and non-parametric methods indicate that specific prior values of  $$M_\textrm{B}$$  <math> <msub> <mi>M</mi> <mtext>B</mtext> </msub> </math>   and  $$r_\textrm{s}$$  <math> <msub> <mi>r</mi> <mtext>s</mtext> </msub> </math>   lead to significant biases on the CDDR test. Then, to avoid these biases, we propose a method independent of  $$M_\textrm{B}$$  <math> <msub> <mi>M</mi> <mtext>B</mtext> </msub> </math>   and  $$r_\textrm{s}$$  <math> <msub> <mi>r</mi> <mtext>s</mtext> </msub> </math>   to test CDDR by considering the fiducial value of  $$\kappa \equiv 10^{M_\textrm{B} \over 5}r_\textrm{s}$$  <math> <mrow> <mi>κ</mi> <mo>≡</mo> <msup> <mn>10</mn> <mfrac> <msub> <mi>M</mi> <mtext>B</mtext> </msub> <mn>5</mn> </mfrac> </msup> <msub> <mi>r</mi> <mtext>s</mtext> </msub> </mrow> </math>   as a nuisance parameter and then marginalizing its influence with a flat prior in the analysis. No violation of the CDDR is found, and the transverse BAO measurement can be used as a powerful tool to verify the validity of CDDR in the cosmological-model-independent method.

Min Wang

Zhenyan Lu

Testing the cosmic distance duality relation with Type Ia supernova and transverse BAO measurements