High Energy Density Physics

This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies √ s N N = 5.5 TeV, will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction -Quantum Chromodynamics (QCD) -in extreme conditions of temperature, density and parton momentum fraction (low-x). This report covers in detail the potential of CMS to carry out a series of representative Pb-Pb measurements. These include "bulk" observables, (charged hadron multiplicity, low p T inclusive hadron identified spectra and elliptic flow) which provide information on the collective properties of the system, as well as perturbative probes such as quarkonia, heavy-quarks, jets and high p T hadrons which yield "tomographic" information of the hottest and densest phases of the reaction.

We present the analysis of between 50 and 100 h of coincident interferometric strain data used to search for and establish an upper limit on a stochastic background of gravitational radiation. These data come from the first LIGO science run, during which all three LIGO interferometers were operated over a 2-week period spanning August and September of 2002. The method of cross correlating the outputs of two interferometers is used for analysis. We describe in detail practical signal processing issues that arise when working with real data, and we establish an observational upper limit on a f Ϫ3 power spectrum of gravitational waves. Our 90% confidence limit is ⍀ 0 h 100 2 р23Ϯ4.6 in the frequency band 40-314 Hz, where h 100 is the Hubble constant in units of 100 km/sec/Mpc and ⍀ 0 is the gravitational wave energy density per logarithmic frequency interval in units of the closure density. This limit is approximately 10 4 times better than the previous, broadband direct limit using interferometric detectors, and nearly 3 times better than the best narrow-band bar detector limit. As LIGO and other worldwide detectors improve in sensitivity and attain their design goals, the analysis procedures described here should lead to stochastic background sensitivity levels of astrophysical interest.

A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution wit...

Proton radiography is the unique experimental technique for obtaining direct information about important material characteristics of real solid objects under dynamic conditions. The aim of the present work is the application of this method to the investigation of evolution of density in ...

A recurring objection to our theory is that it cannot explain spherical light bending (gravitational lensing) around galaxies. Critics claim that our model only explains the flat rotation curve, but not why light is bent in all directions -not only in the galactic plane. This is a misunderstanding. We show here that the standard model has a much larger problem, and that our theory provides a unified, physical explanation for both phenomena.

A recurring objection to our theory is that it cannot explain spherical light bending (gravitational lensing) around galaxies. Critics claim that our model only explains the flat rotation curve, but not why light is bent in all directions -not only in the galactic plane. This is a misunderstanding. We show here that the standard model has a much larger problem, and that our theory provides a unified, physical explanation for both phenomena.

We propose a generalized metric, denoted G, applicable to the universe as a whole, considered in the first instance to be homogeneous, without any particular perspective on it, and filled with matter at its average density. The low density of this matter allows for the weak-field approximation and the summation of terms involving individual masses M/r (where r is the distance from the observer), described by the Schwarzschild metric, extended to a continuous cosmological medium. This leads to a global gravitational potential proportional to ρuRu 2 , where ρu is the average density and Ru is a cosmological scale of the universe (its Hubble radius). The resulting metric can be interpreted in terms of the effective refractive index of vacuum on the cosmological scale: the coefficients of the metric and the index are functions of quantities associated with the universe as a whole (summarized in the gravitational potential Φ and the deviation Ω from flatness). The calculation of the index value is performed in two steps. In the first step, we consider a critical universe such as our own (homogeneous approximation). The index is exactly equal to 2. In the second step, an increase in the index, up to a value possibly equal to 2.4, results from the effect of deviations from the homogeneity of the universe, and from the nonlinear relationship between the index and density. As shown in our previous works, the propagation of light on a cosmological scale at a speed 2.4 times slower than its value c0 in the "local" vacuum (our laboratories, our solar system) provides a single solution to the dozen problems on the dark side of astrophysics, which authors currently address separately. The incorporation into a metric of the gravitational potential created by the mass of the universe offers a fresh perspective on Mach's principle and Newton's first law: the law of inertia is the response to the influence of the total mass of the universe. The equality of inertial mass and gravitational mass is also understood for a critical universe (the gravitational potential is of the order of c0 2). Conversely, the criticality of the universe is not the result of a chance encounter between two unrelated quantities (the speed of light on one hand, the mass of the universe on the other) but the expression of their natural connection within a physical regularity that can be expressed only in relational terms (they cannot be described separately). Flatness is an expression of Mach's principle revisited and extended, and does not require inflation. The text proposes a preliminary explanatory framework and orders of magnitude for the physical parameters, as a basis for future, more comprehensive revisions of existing models (expansion models without dark matter or dark energy).

The derivation of a theoretical model for the decaying convective turbulence in a shearbuoyancy planetary boundary layer is considered. The model is based on the dynamical equation for the energy density spectrum in which the buoyancy, mechanical and inertial transfer terms are retained. The parameterization for the buoyancy and mechanical terms is provided by the flux Richardson number. Regarding the inertial term an approach employing Heisenberg's spectral transfer theory is used to describe the turbulence friction, caused by small eddies, responsible for the energy dissipation of the large eddies. Therefore, a novelty in this study is to utilize the Adomian decomposition method to solve directly without linearization the energy density spectrum equation, with this the nonlinear nature of the problem is preserved. Therefore, the errors found are only due to the parameterization used. Comparison of the theoretical model is performed against largeeddy simulation data for a decaying convective turbulence in a shear-buoyancy planetary boundary layer. The results show that the existence of a mechanical turbulent driving mechanism reduces in an accentuated way the energy density spectrum and turbulent kinetic energy decay generated by the decaying convective production in a shear-buoyancy planetary boundary layer.

The choice of copper/low-k interconnect architectures is instrumental in achieving high device performances. Today, the implementation of porous low-k materials becomes mandatory in order to compensate metal resistance increase upon RC product. However, their introduction, which was initially planned for the 65nm technological node, was delayed to 45nm node due to integration issues. Using an integration strategy which combines porous SiOCH materials and metal hard masks, the difficulties and possible solutions are presented in this paper with emphasis on plasma etching.

This paper presents a complete, zero-parameter derivation of the weak mixing angle sin2θW from the Chrono Singularity Unification (ΨI ) framework.

We demonstrate that the weak mixing angle is not an arbitrary free parameter of the Standard Model, but rather emerges as a rigid topological invariant determined by the
golden ratio ϕ = (1 + √5)/2.

Beginning from the exact topological baseline sin2θW = 1/(1 + ϕ2) ≈ 0.27639 in the unbroken symmetric bulk, we derive the discrete condensation at the Electroweak symmetry breaking scale (v = 246.22 GeV), yielding sin2
θW (v) = 1/ϕ3 ≈ 0.23607.

We then execute standard
one-loop Standard Model renormalization group running from the vacuum expectation value to the Z-boson mass scale (MZ = 91.1876 GeV), arriving at sin2θW (MZ) = 0.23108.

Finally, we derive the top quark threshold correction of +0.00014 from the ΨI framework principles. Our final theoretical prediction is: sin2θW (MZ) = 0.23122

(1) The Particle Data Group experimental world average is: sin2θ exp W (MZ) = 0.23122 ± 0.00003
(2) This represents perfect agreement to four decimal places with zero free parameters— a smoking gun prediction that distinguishes the CSU framework from all other theoretical approaches.

Using the efficient absorption of laser energy by clustered gases allows the study of high energy density systems at low average density with table-top scale lasers. Thus generation of radiative shocks at moderate drive energies in high Z materials can be achieved for the purpose of ...

Temporal Continuum Branching Theory (TCBT) proposes that time is discrete at intervals of the Planck time t_P, with quantum events corresponding to branchings of the universal wavefunction. This paper reformulates the framework on four fronts. First, the branching probability is derived from the Born rule applied to one-step unitary evolution, replacing an earlier heuristic and recovering standard quantum mechanics in the continuum limit. Second, a falsifiable prediction is developed: a log-periodic modulation of the scalar power spectrum with fractional amplitude α ~ H_inf · t_P ≈ 10⁻⁵ and period N_TCBT ≈ 11.5 inflaton e-folds, testable by templated searches on CMB-S4 and LiteBIRD data. Third, the black hole information argument is reframed within the quantum extremal surface / islands programme. Fourth, the foliation problem is resolved by making branching a local proper-time phenomenon, restoring Lorentz invariance at macroscopic scales.

[1] present a set of equations governing the evolution of two-dimensional MHD flows using current-vortex sheets. In the resulting model the vorticity ω and current density j are zero except on the current-vortex sheets. We show that this is not true in general and that the term ∆(B × u) in the evolution equation for j does not vanish, leading to the generation of j and ω in the bulk. This means that the evolution of the system is not governed solely by the dynamics of quantities on the current-vortex sheets. A perturbative solution is derived that shows this explicitly.

We develop the fifth continuum element connecting closure transport to relativistic stress-energy structure within the Mo framework: closure anisotropic stress. Previous stages identified closure flux, closure energy density, closure momentum density, and closure pressure through the hierarchy C → J^µ C → ρC → p^(C) µ → PC. These elements account for conserved transport, local source concentration, directed momentum flow, and isotropic compression response. The remaining major continuum sector is anisotropic stress, denoted Π^(C) µν , which encodes directional distortion and shear-like organization of closure transport. We construct the minimal anisotropic closure stress sector using the spatial projector orthogonal to the transport flow and the shear tensor associated with the closure congruence. The resulting effective closure tensor takes the form T^(C) µν = ρC uµuν + PC hµν + Π^(C) µν. We emphasize that this fifth element is the most structurally demanding because scalar closure alone cannot generate anisotropy. Anisotropic closure stress requires organized deformation of transport, shear, projection geometry, or a constitutive relation connecting closure distortion to tensorial stress.

This paper is the sixteenth in the Rodrik series. We refute Erik Lentz's 2021 claim to have found a warp drive solution requiring no exotic matter-a proposal published in Classical and Quantum Gravity that attracted significant attention as the first warp metric apparently consistent with positive local energy conditions. We demonstrate that the claim is false on three independent grounds. The Primary Refutation-the Local-Global Fallacy and Global ANEC Violation-identifies the central error in Lentz's proposal: while his soliton metric uses only positive local energy density in the stress-energy tensor, the Averaged Null Energy Condition is not a local condition. It is an integral condition along complete null geodesics. When null geodesics threading Lentz's soliton are integrated across the full spacetime trajectory-including the regions ahead of and behind the soliton where the metric returns to flat Minkowski space-the ANEC integral is negative. The soliton violates the ANEC globally even though every local measurement of energy density is positive. This error-confusing local positivity with global ANEC compliance-is the Local-Global Fallacy, proposed as an eleventh element of the Rodrik Framework. The Secondary Refutation-FTL Implies BTT-shows that Lentz's soliton, traveling at superluminal effective speed, implies backward time travel in boosted reference frames regardless of its energy conditions. The FTL-implies-BTT argument of Paper 7 applies without modification. The Tertiary Refutation-the Peer Review Gap-notes that Lentz's global ANEC compliance claim has not been independently verified and that multiple subsequent analyses have identified the global ANEC violation. The proposal's claimed breakthrough-exotic-matter-free warp drive-rests on a calculation that conflates a local condition with a global one.

We construct a 16-dimensional Lorentzian manifold with a Dimensional Tension Limit (DTL) regulator that enforces a hard upper bound on the Kretschmann scalar. Dimensional reduction on an explicit quintic Calabi-Yau threefold with a 4-line monad bundle yields a realistic 4D MSSM with exactly three chiral generations. Every core mechanism has been subjected to exhaustive numerical validation through 30+ independent high-precision simulations. These tests confirm dynamical singularity resolution in black holes () and cosmology (smooth bounce), ghost-free perturbations, Planckcompatible cosmology, realistic fermion masses, viable bino-like neutralino dark matter with exact Planck relic density , and HL-LHC-testable signatures. The DTL regulator reproduces the bounded-curvature bounce dynamics of Loop Quantum Gravity effective models while adding explicit heterotic unification. It resolves the black-hole information paradox through higher-dimensional NVW bleed and entanglement preservation, explains wavefunction collapse and the double-slit paradox as deterministic dimensional truncation, and accounts for Heisenberg's uncertainty principle as a byproduct of analog node digitization under finite observational bandwidth. Dark energy arises dynamically from DTL relaxation pressure after moduli stabilization. Sharp predictions include measurable ringdown frequency shifts (+5.2%), clustered MET patterns at the LHC, and a narrow proton decay lifetime window. All 30+ simulations remain 100% consistent after multiple robust reruns .

The particle dark matter paradigm has dominated cosmology and particle physics for four decades. It posits that 85% of the universe's matter consists of weakly interacting massive particles (WIMPs), axions, sterile neutrinos, or other exotic fermions. After 15 years of LHC operation at multi-TeV energies, two decades of direct detection experiments (XENON, LUX, PandaX, DAMA/LIBRA), and extensive indirect detection searches (Fermi-LAT, AMS-02, IceCube), no dark matter particle has ever been observed. The null results are not ambiguous. They are consistent, persistent, and cover nearly the entire theoretically motivated parameter space for WIMPs. The recent gravitational wave freeze-in proposal by Maleknejad and Kopp (2026) correctly identifies early universe vacuum dynamics as relevant to dark matter generation. However, their framework remains trapped within the particle paradigm, treating dark matter as a fermion or boson produced by vacuum fluctuations. The ontological error is the same: assuming that dark matter is a "thing" rather than a "state." We present the KUTE framework (Kaundinya's Unified Theory of Everything), derived from first principles beginning with the Collatz parity-block map. The framework yields the primordial invariant ∆ = 4 ln 99 ≈ 18.3804794005 and the quadratic regulator:

The two-force mechanical cosmology presented here models the universe as a substrate-driven system governed by two fundamental interactions: a flux-deficit attractive force generated by matter's absorption of substrate momentum, and an inelastic repulsive-floor force that activates at the Planck-scale compression limit. In this framework, curvature is not a primitive geometric property but an emergent macroscopic description of underlying mechanical flux gradients. Gravitational behavior, structure formation, and inertial response arise from the interaction between matter and the substrate's directional momentum field, while the repulsive floor prevents singularities and establishes a finite-density boundary condition for all high-compression states. Cosmic evolution proceeds through a cyclic engine in which contraction increases substrate loading until the repulsive floor triggers a bounce, initiating expansion. Sequestered antimatter forms neutral gravitational fuel cells that generate smooth flux-deficit wells, providing the dark-matter analogue without particulate dark matter. Late-time acceleration emerges mechanically from the thermodynamic expansion of the cosmic sink rather than from vacuum energy or a cosmological constant. Quantum behavior reflects the discrete, script-level interaction rules of the substrate rather than intrinsic probabilistic indeterminacy. This model replaces singularities, inflation, dark energy, and non-mechanical quantum postulates with a unified substrate-mechanical architecture. It yields testable predictions for compact-object density limits, gravitational-wave signatures, lensing profiles, and large-scale structure coherence. The result is a coherent, deterministic cosmology in which gravity, quantum behavior, and cosmic evolution emerge from a single mechanical substrate governed by two forces.

Among the uncommon features of graphene monolayer we find the presence of zero energy states localized at zigzag edges, leading to the self-doping phenomenon and inducing edge magnetization. Here we report the existence of zero energy surface states localized at zigzag edges of bilayer graphene and stacks with any number of layers. Working within the tight-binding approximation we derive an analytic solution for the wavefunctions of these peculiar surface states. It is shown that zero energy edge states in bilayer graphene can be divided into two families: (i ) states living only on a single plane, equivalent to surface states in monolayer graphene; (ii ) states with finite amplitude over the two layers, with an enhanced penetration into the bulk. The effect of edge states on the electronic structure and magnetic order of bilayer graphene nanoribbons is also studied. We show that edge states measured through scanning tunneling microscopy and spectroscopy of graphite step edges belong to family (i ) or (ii ) mentioned above, depending on the way the top layer is cut.

The lithium molybdenum disulfide system as demonstrated in a C size cell, offers performance characteristics for applications where light weight and low volume are important. A gravimetric energy density of 90 watt hours per kilogram can be achieved in a C size cell package. The combination of charge retention capabilities, high energy density and a state of charge indicator in

We derive quantum gravity from the stochastic copying dynamics of simplicial defects in the Information-Copying Cosmology framework. The emergent metric field g µν (x) arises from fluctuations in the local copying rate H(x, t), with the Einstein-Hilbert action generated by the Martin-Siggia-Rose (MSR) path integral.

This paper develops the dynamical layer of the Knot Universe series, building on the structural definitions of Paper #62 and the observational predictions of Paper #63.
The central proposal is that cosmic evolution can be understood as a single phase trajectory: from a hyper-condensed regime (Hyper-JAM) through a global phase-unfolding transition (interpreted as the Big Bang), into a CRGZ coherence window that enables structure formation, and finally into branching outcomes determined by local knot density and throat-passage timing.
Key contributions of this paper include:
(1) Reinterpreting the Big Bang not as a kinematic explosion, but as a global amplitude expansion from a structurally closed phase state — a release of accumulated topological constraints.
(2) Introducing a Cosmic Hourglass Phase Map that unifies filaments, voids, and black holes as different branches of a single underlying phase evolution.
(3) Modeling black holes as JAM-limit regimes of extreme local phase condensation, and interpreting JWST "Little Red Dots" as candidates for Phase Acceleration Zones — regions of accelerated pre-JAM condensation.
(4) Identifying the emergence of internal time as a structural consequence of phase differentiation under non-degenerate geometry (δ₃ > 0), providing a topological basis for the arrow of time.