Echoes of the Universe: Simulating Cosmic Expansion with Bose-Einstein Condensates
![The study of an expanding universe analog reveals a distinct partitioning of phonon production based on a scale defined by [latex] k_l = 1/2 [/latex], where, below this threshold, phonon numbers ([latex] N_k [/latex]) scale symmetrically with time, while above it, they oscillate with a log-periodic function of time, demonstrating a fundamental shift in behavior at the sub-horizon and super-horizon regimes.](https://arxiv.org/html/2603.16095v1/x2.png)
Researchers have created an analog universe within a supercooled gas to observe the production of particles mimicking the behavior of an expanding cosmos.
Science
Relativity Meets the Quantum: The Enduring Legacy of Dirac
A new review traces the origins and modern interpretations of the Dirac equation, a cornerstone of relativistic quantum mechanics.
Beyond Optimization: AI-Powered Microscopy Hunts for the Unexpected
A new framework uses artificial intelligence to actively explore sample responses in microscopy, prioritizing discovery of novel behaviors over simply maximizing known signals.
Twisted Physics: Unlocking New States in 2D Materials
This review explores how confining electrons in layered, two-dimensional crystals creates exotic quantum phenomena with the potential to reshape materials science.
Decoding Quantum Matter with Machine Learning
![The study correlates the crystal structure of [latex]Nd_{1-x}Sr_xNiO_3[/latex]-and its resulting nickel electronic configuration-with the architecture of a five-layer SIREN model designed to predict spectral intensity, demonstrating a machine learning approach capable of reproducing Fermi surface characteristics previously calculated through tight-binding methods.](https://arxiv.org/html/2603.16725v1/x1.png)
A new framework leverages artificial intelligence to map the electronic structure of materials from experimental data, accelerating the discovery of next-generation quantum materials.
Mapping the Extreme: Exploring QCD Matter Under Pressure
![Lattice QCD calculations, when confronted with experimental data from STAR BES-II and ALICE, reveal correlations between strangeness and [latex]\mu_{S}/\mu_{B}[/latex], alongside a generalized isothermal compressibility [latex]\kappa_{T,\sigma_{Q}^{2}}[/latex], ultimately illustrating the onset of quark-like charm degrees of freedom as the system crosses over to the quark-gluon plasma phase.](https://arxiv.org/html/2603.16230v1/figures/P_charmquark.png)
This review details recent advancements in understanding the behavior of quark-gluon plasma and dense hadronic matter using state-of-the-art lattice QCD simulations.
Shining Light on Dark Matter: New Axion Search Sets Stringent Limits
![The experiment established improved bounds on the [latex]a_\gamma\gamma[/latex] coupling by excluding a broad mass region-specifically, for [latex]m_{a\gamma\gamma} < 22[/latex] eV and within the range [latex](3462, 3482)[/latex] eV-reaching down to the QCD coupling as defined in Eq. (2), with the precision of these bounds determined by the effective rocking curve of the germanium crystals used, and representing a significant advancement over previous measurements from EuXFEL, NOMAD, BaBar, SAPPHIRES, ALPS, and PVLAS.](https://arxiv.org/html/2603.15808v1/x4.png)
Researchers have employed a powerful X-ray laser and a ‘light-shining-through-walls’ technique to push the boundaries of axion-like particle (ALP) detection.
Beyond Bosons and Fermions: How Anyons Rewrite the Rules of Quantum Motion
![In a one-dimensional interacting anyonic system, a quantum quench induces a transition in dynamical scaling where particle-number fluctuations shift from ballistic to superdiffusive behavior as the statistical angle increases, while the von Neumann entanglement entropy remains consistently ballistic-a phenomenon arising from density-dependent tunneling and interactions within the lattice, described by [latex]J_{ei}\theta_n[/latex] and [latex]U[/latex], respectively.](https://arxiv.org/html/2603.15972v1/x1.png)
New research reveals that interacting anyons in one-dimensional systems exhibit unusual dynamic behavior, deviating from standard particle diffusion and entanglement patterns.
Sensing with Layers: A New Quantum Filter
Engineered van der Waals heterostructures offer a pathway to create quantum sensors that selectively detect particles based on their energy and momentum.
Spacetime from Quantum Fluctuations
![The evolving abundance of dark matter halos exceeding [latex]10^8\,M_{\odot}[/latex] demonstrates a redshift-dependent density, calculated via the Sheth-Tormen mass function and a standard transfer function, and subject to modulation by a power boost parameter-a relationship sensitive to underlying cosmological parameters and the scale-dependent behavior of that boost.](https://arxiv.org/html/2603.14533v1/fig_hmf_boost.png)
A new framework links the fabric of spacetime to the fundamental quantum properties of operators, potentially offering insights into the universe’s earliest moments.