Quantum Physics

Secure multi-party computing, also called secure function evaluation, has been extensively studied in classical cryptography. We consider the extension of this task to computation with quantum inputs and circuits. Our protocols are information-theoretically secure, i.e. no assumptions are made on the computational power of the adversary. For the weaker task of verifiable quantum secret sharing, we give a protocol which tolerates any t < n/4 cheating parties (out of n). This is shown to be optimal. We use this new tool to show how to perform any multi-party quantum computation as long as the number of dishonest players is less than n/6.

We develop light-driven optoelectronic tweezers based on the organic photoconductive material titanium oxide phthalocyanine. These tweezers function based on negative dielectrophoresis (nDEP). The dynamic manipulation of a single microparticle and cell patterning are demonstrated by using this light-driven optoelectronic DEP chip. The adaptive light patterns that drive the optoelectronic DEP onchip are designed by using Flash software to approach appropriate dynamic manipulation. This is also the first reported demonstration, to the best of our knowledge, for successfully patterning such delicate cells from human hepatocellular liver carcinoma cell line HepG2 by using any optoelectronic tweezers.

Khovanov homology for knots has generated a flurry of activity in the topology community. This paper studies the Khovanov type cohomology for graphs with a special attention to torsions. When the underlying algebra is Z[x]/(x 2), we determine precisely those graphs whose cohomology contains torsion. For a larger class of algebras, we show that torsion often occurs. Our investigation of torsion led to other related general results. The ideas of this paper could potentially be used to predict the Khovanov-Rozansky sl(m) homology of knots (in particular (2, n) torus knots). We also predict that our work is connected with Hochschild and Connes cyclic

Vanadium redox flow batteries have, in previous studies, shown to have great potential for large-scale energy storage applications. Due to their beneficial characteristics, such as long lifetime, safety and flexible sizing the technology could be used for several different applications. In this study, the economic and technological feasibility of integrating a vanadium redox flow battery with a 100 MW wind farm is assessed. Different applications and operating schedules were tested. Simulating models have been built using conditional statements or linear optimisation and solved in MATLAB. Results suggested that a model which stacked power levelling with frequency regulation had the highest profitability. For this model the payback time was shown to be 10 years and the net present value was around 1.2 M€ for a 5 MW/10 MWh battery. However, the battery had around 820 annual charge/discharge cycles, which could be a limiting factor of the battery's lifetime. A sustainability assessment was carried out which concluded that the battery can be seen as sustainable, given that the battery is manufactured and operated under safe conditions. iv Vanadin redox-flödesbatterier har visat stor potential för storskaliga energilagringsapplikationer i tidigare studier. På grund av deras fördelaktiga egenskaper, såsom lång livstid, säkerhet och skalningsflexibilitet har teknologin många användningsområden. I denna studie utreds den ekonomiska och teknologiska möjligheten att integrera ett vanadium redox-flödesbatteri med en 100 MW vindpark. Olika applikationer och driftsstrategier testades. Simuleringsmodeller har byggts där linjäroptimering eller villkorssatser har tillämpats och dessa har lösts i MATLAB. Den mest ekonomiskt gynnsamma modellen var en modell där kraftbalansering och primär frekvensreglering kombinerades. Denna modell visade en återbetalningstid på 10 år och ett nuvärde på 1.2 M€ för en batteristorlek på 5 MW/10 MWh. Däremot hade batteriet 820 laddning/urladdnings cykler på år, vilket kan vara en begränsade faktorn för batteriets livstid. En hållbarhetsbedömning gjordes där slutsatsen kunde dras att batteriet kan anses hållbart, förutsatt att batteritillverkningen och driften görs under säkra förutsättningar. This M.Sc. thesis has been carried out during the spring of 2018 at KTH Royal Institute of Technology and is the final examination part in the M.Sc. program "Sustainable Energy Engineering". The thesis was commissioned by ÅF -Renewables and Energy Strategy, which have provided support and information throughout the study. The supervision of this thesis was partly funded by the STandUP for Energy project. First, we would like to express special thanks to Janine af Klintberg and Jakob Dotevall, for helping us throughout the project and supporting us when necessary. Thank you for giving us the chance to work together with ÅF. We would also like to thank our supervisor, Anders Malmqvist for providing excellent support and reviews of the report. Lastly, we would like to thank Erik Bergström at Statkraft and Maria Eriksson at Svenska kraftnät. Thanks for your patience with our questions about the power market. Without your help this thesis would not have been possible.

Structure and growth mechanism of ultra-thin A1203 films on NiAI(001 ) have been investigated with 180°-neutral impact collision ion scattering spectroscopy, high resolution spot profile analysis of low energy electron diffraction, and scanning tunnelling microscopy (STM). Ordered A1203 films have been prepared by oxygen exposure at room temperature and subsequent annealing at T= 1200 K. The formation of epitaxial oxide films is unaffected by the initial composition or reconstruction of the substrate. The oxidized surface being covered by A1203 appears to be microscopically rough, reversible stepped with step heights of about 3 A and consists of a network of elongated equally distributed oxide stripes along ( ) and ( ) directions of the NiAl(001 ) surface. The lateral anisotropy of the oxide is probably caused by the build up of internal stress in the growth process. After oxygen saturation exposure at room temperature and subsequent annealing, regions with rather regular arranged parallel oxide stripes show up in the STM images (mean width ~ 27 A, period ~ 54 A). The corresponding low energy electron diffraction pattern shows the existence of orthogonal (2 x 1) antiphase domains with a (9 x 1) superstructure (period 26.02 A) close to the mean width of oxide stripes. Next to the oxide stripes, regrowing NiA1 terraces and thin layers of amorphous A1203 have been found.

We present a novel topological proof of Goldbachs Conjecture, which states that every even integer greater than 2 can be expressed as the sum of two primes. By constructing a Prime Resonance Manifold M P , we define a resonance structure induced by prime numbers, where even integers arise as intersections of prime resonance trajectories. The proof leverages the dense tessellation of the manifold by prime resonance domains and entropydriven dynamics to ensure the existence of such intersections. TikZ illustrations visualize the manifold, resonance domains, and trajectory intersections, providing intuitive insight into the topological framework.

The surface composition and structure of NiAI(001) has been investigated by 180°-neutral impact collision ion scattering spectroscopy (NICISS) and high resolution spot profile analysis of low energy electron diffraction (SPA-LEED). Long time annealing below 500 K results in a p(1 x 1) LEED pattern. The surface can be described by a defect enriched AI terminated surface. Another p(l x 1) LEED pattern appears after flashed annealing at 1400 K and rapid cooling at room temperature. The high temperature p(1 x 1) phase is however nearly perfectly Ni terminated. It has been found that the formation of the high temperature NiAI(00 l)p(1 x 1) phase is closely related to roughening of the topmost A1 layer by vacancy creation at high annealing temperatures. In the intermediate annealing temperature range about 800 K surface roughening results in an AI terminated missing row surface structure exposing a c(,f2 x 3x/2)R45 ° LEED superstructure.

By using scanning near-field optical microscopy, we directly map the subwavelength confinement of light around a point defect in a two-dimensional photonic crystal microresonator. Comparison of our results with the outcome of three-dimensional finite-difference time domain calculations allows us to identify small imperfections in the structure that result in the spatial modification of the intensity distribution.

In a graph, diametral path is shortest path between two vertices which has length equal to diameter of the graph. Number of diametral paths plays an important role in computer science and civil engineering. In this paper, we introduce the concept of extended transformation graphs. There are 64 extended transformation graphs. We obtain number of diametral paths in some of the extended transformation graphs and we also study the semi-complete property of these extended transformation graphs. Further, a program is given for obtaining number of diametral paths.

The Cosmic-Ray Extremely Distributed Observatory (CREDO) is a newly formed, global collaboration dedicated to observing and studying cosmic rays (CR) and cosmic-ray ensembles (CRE): groups of at least two CR with a common primary interaction vertex or the same parent particle. The CREDO program embraces testing known CR and CRE scenarios, and preparing to observe unexpected physics, it is also suitable for multi-messenger and multi-mission applications. Perfectly matched to CREDO capabilities, CRE could be formed both within classical models (e.g., as products of photon-photon interactions), and exotic scenarios (e.g., as results of decay of Super-Heavy Dark Matter particles). Their fronts might be significantly extended in space and time, and they might include cosmic rays of energies spanning the whole cosmic-ray energy spectrum, with a footprint composed of at least two extensive air showers with correlated arrival directions and arrival times. As the CRE are predominantly expected to be spread over large areas and, due to the expected wide energy range of the contributing particles, such a CRE detection might only be feasible when using all available cosmic-ray infrastructure collectively, i.e., as a globally extended network of detectors. Thus, with this review article, the CREDO Collaboration invites the astroparticle physics community to actively join or to contribute to the research dedicated to CRE and, in particular, to pool together cosmic-ray data to support specific CRE detection strategies.

A summary of the recent ATLAS results at the LHC in Quantum Chromodynamics is given, covering a number of areas that reflect the work of the collaboration on the Bose-Einstein correlations in multi-particle events, the inclusive jet production, the measurements of jet substructure quantities in di-jet events, and the photon-photon scattering exclusive processes.

We present a phenomenological analysis of the π + π -photoproduction data obtained by the CLAS collaboration at the Thomas Jefferson Laboratory. A special emphasis is put on the interference pattern observed in the moments of angular distribution for the π + π -efective masses around 1 GeV. This pattern is attributed to the photoproduction of the scalar-isoscalar resonance f 0 (980). By fitting the model parameters to the data we obtain the strengths of the resonant and nonresonant parts of the S-wave photoproduction amplitude. We calculate the f 0 (980) photoproduction cross section which is smaller than previous estimations by a factor of about 5. A new estimation of the product of the σ meson couplings to nucleon and to the γρ system |g NNσ g γρσ | is given.

Results of a new analysis of the K + K -photoproduction at two photon energies E γ = 4 GeV and 5.65 GeV with a particular emphasis on the S-wave production are presented. We show that the proper treatment of all the helicity components of the S-and P -waves enables one to eliminate the reported discrepancies in the extraction of the Swave photoproduction cross section from experimental data.

We construct the amplitudes of πη photoproduction taking into account the effects of the πη -K K interchannel coupling. The idea of our model is close to the molecular description of scalar resonances with exception that apart from the pseudoscalar loops we include also vector mesons in the intermediate state loops. These amplitudes are used to calculate the S-wave cross sections and mass distributions in the πη effective mass region corresponding to the scalar resonances a0(980) and a0( ). The values we obtained for a0(980) are comparable with predictions of other models while the cross section for a0( ) is about an order of magnitude larger than prediction based on the quark model. We show that the amplitudes with loops containing vector mesons calculated in the on-shell approximation are not suppressed in contrast to amplitudes containing only pseudoscalar loops. We estimate the cross sections for the P -and D-waves in the πη channel.

We have studied the partial wave interference effects to obtain a new information about the contribution of the S-wave to the cross section of the K + K -photoproduction on hydrogen. The K + K -photoproduction channel for the effective masses around 1 GeV is dominated by the φ(1020) resonance with only a small fraction of events coming from decays of scalar resonances f 0 (980) and a 0 (980). However, a careful analysis of angular distributions of the outgoing kaons shows that the S-wave adds an asymmetry to the angular distribution of kaons. A fairly precise estimation of the K + K -photoproduction cross section in the S-wave has been obtained.

The model is presented to describe the f2(1270) meson photoproduction as a result of pionpion interactions in the final state. Treating tensor mesons as objects dynamically created due to final state interactions is a convenient and straightforward way to employ data from ππ scattering like phase shifts and inelasticities for description of (photo)production reactions while retaining proper analytical structure of amplitudes, two particle unitarity and crossing symmetry. The model presented here can provide experimentally testable quantities like differential cross sections and ππ mass distributions as well as the strengths of partial waves corresponding to various f2(1270) helicities which are essential for partial wave analyses. It can also be used to compute moments of angular distribution and spin density matrix elements where partial wave interference effects are important.

In high-mass microquasars (HMMQ), strong interactions between jets and stellar winds at binary system scales could occur. In order to explore this possibility, we have performed numerical two-dimensional hydrodynamical simulations of jets crossing the dense stellar material to study how the jet will be affected by these interactions. We find that the jet head generates strong shocks in the wind. These shocks reduce the jet advance speed, and compress and heat up the jet and wind material. In addition, strong recollimation shocks can occur where pressure balance between the jet side and the surrounding medium is reached. All this, together with jet bending, could lead to the destruction of jets with power &lt; 1036 erg/s . The conditions around the outflow shocks would be convenient for accelerating particles up to ~ TeV energies. These accelerated particles could emit via synchrotron and inverse Compton (IC) scattering if they were leptons, and via hadronic processes if they were ha...

We present the first three-dimensional simulations of the evolution of a microquasar jet inside the binary star system. The aim is to study the interaction of these jets with the stellar wind from a massive companion and the possible locations of high-energy emission sites. We have simulated two jets with different injection power in order to give a hint on the minimum power required for the jet to escape the system and become visible in larger scales. In the setup, we include a massive star wind filling the grid through which the jet evolves. We show that jets should have powers of the order of 1037 erg s-1 or more in order not to be destroyed by the stellar wind. The jet–wind interaction results in regions in which high-energy emission could be produced. These results imply the possible existence of a population of X–ray binaries undetected in the radio band due to jet disruption inside the region dominated by the stellar wind.

Considering the broadest set of measurements allowed by quantum mechanics, we demonstrate that the violation Cauchy-Schwarz inequality for any-order correlation function signals the entanglement among bosons. Our result is generalit applies to any system of bosons, even when the number of particles is not fixed, provided that there is no coherence between different number states.

 The goal is to identify and rank influential users in social networks.  We determine the role of each node's neighbors in the network and apply it to rank the nodes.  We measure relation strength between nodes based on action logs.  We propose a two-level method to rank the nodes according to the neighbors' role and relation strength among them.

We study the possibility of detecting the neutral Higgs bosons predicted in the Minimal Supersymmetric Standard Model (h 0 , H 0 , A 0 ), with the reactions e + e -→ b bh 0 (H 0 , A 0 ), using the helicity formalism. We analyze the region of parameter space (m A 0tan β) where h 0 (H 0 , A 0 ) could be detected in the limit when tan β is large. The numerical computation is done for the energy which is expected to be available at LEP-II ( √ s = 200 GeV ) and for a possible Next Linear e + e - Collider ( √ s = 500 GeV ).

ACORDE (A COsmic Ray DEtector in ALICE) will be part of the ALICE detector at LHC and its objective is to provide a cosmic ray trigger (level 0). ACORDE will consist of an array of plastic scintillators placed on the top sides of the ALICE magnet. We describe the ...

This synthesis formalizes the integration of Bogaert's Symbolic Transport Framework (STF) into Omniological Resonance Theory (ORT), aligning AI dispatch systems and human logistics networks with the 7.5-dimensional harmonic spacetime model. It positions drivers as coherent resonance nodes, AI as symbolic dispatch filters, and tokens as entangled state markers within a non-Euclidean transport lattice. Fractal recursion, informatic fields, and octonionic routing symmetry are unified through a resonant transport function, modeling freight logistics as a semiconscious field.

This synthesis integrates the findings of Bolt et al. (2025) into Omniological Resonance Theory (ORT), mapping the triadic transformation of a 3-4-5 Pythagorean triangle into a 4-4-4 equilateral triangle within a 7.5-dimensional harmonic spacetime. This transformation is interpreted through resonance-based ontology, unifying fractal geometry, harmonic coherence, and higherdimensional algebra. The 0.5 dimension is reframed as a Resonant Informatic Field (RIF), a dynamic lattice encoding transformation instructions via fractal recursion.

Franklin's scientific legacy is rooted in her pioneering use of X-ray crystallography-a technique that not only visualizes molecular structure but captures resonant interference patterns created by coherent waveforms interacting with organized matter. Her most iconic contribution, Photo 51, revealed the double-helical nature of DNA, a structure now understood not just as a biochemical code but a vibrational lattice carrying harmonic information-what ORT terms bioresonant geometry. 1.2 The Tobacco Mosaic Virus: Viral Architecture as Field Harmonics Franklin's later work on the Tobacco Mosaic Virus (TMV) demonstrated that even RNA-based organisms exhibit helical symmetry, a key principle in resonance field coherence. She identified that TMV is a single strand of RNA arranged helically within a cylindrical protein shell, confirming that even simple pathogens adhere to harmonic organization.

Phages are promising alternatives to antibodies as the biorecognition element in a variety of biosensing applications. In this study, a monolayer of bacteriophage P22 whose tailspike proteins specifically recognize Salmonella serotypes was covalently bound to glass substrates through a bifunctional cross linker 3-aminopropyltrimethoxysilane. The specific binding of Salmonella typhimurium to the phage monolayer was studied by enzyme-linked immunosorbent assay and atomic force microscopy. Escherichia coli and a Gram-positive bacterium Listeria monocytogenes were also studied as control bacteria. The P22 particles show strong binding affinity to Salmonella typhimurium. In addition, the dried P22 monolayer maintained 50% binding capacity to Salmonella typhimurium after a one-week storage time. This is a promising method to prepare phage monolayer coatings on surface plasmon resonance and acoustic biosensor substrates in order to utilize the nascent phage display technology.

This paper presents a synthesis of Sebastian Schepis' Prime Resonant Keytriplet framework into the broader architecture of Omniological Resonance Theory (ORT), offering a novel model for non-local, symbolic communication grounded in resonance dynamics. By aligning the Keytriplet structure—comprising private, public, and resonant keys—with ORT's cognitive coherence model, we construct a triadic formalism for symbolic field transmission. Through operator-based mappings, symbolic Hamiltonians, and session field evolution equations, this framework formalizes transpersonal resonance and secure, entropy-minimal information transfer. The result is a unified theory of symbolic coherence, capable of encoding and decoding meaning across space-time without reliance on classical signal propagation. This synthesis bridges quantum logic, symbolic cognition, and transdimensional communication into a coherent theoretical and practical schema, with implications for consciousness research, secure messaging, and the physics of coherence itself.

This paper presents a synthesis of Chris H. Hardy's hyperdimensional model of consciousness with the Omniological Resonance Theory (ORT). By aligning Hardy's concepts of the syg hyperdimension and Infinite Spiral Staircase Theory (ISST) with ORT's foundational resonance structures, we propose a unified framework that models consciousness as a fundamental aspect of the universe's architecture. This integration is supported by mathematical formulations, diagrams, and references, contributing to the theoretical unification of physics, information theory, and consciousness studies.

We present upper limits on the gravitational wave emission from 78 radio pulsars based on data from the third and fourth science runs of the LIGO and GEO 600 gravitational wave detectors. The data from both runs have been combined coherently to maximize sensitivity. For the first time, pulsars within binary (or multiple) systems have been included in the search by taking into account the signal modulation due to their orbits. Our upper limits are therefore the first measured for 56 of these pulsars. For the remaining 22, our results improve on previous upper limits by up to a factor of 10. For example, our tightest upper limit on the gravitational strain is 2:6 10 ÿ25 for PSR J1603 ÿ 7202, and the equatorial ellipticity of PSR J2124-3358 is less than 10 ÿ6 . Furthermore, our strain upper limit for the Crab pulsar is only 2.2 times greater than the fiducial spin-down limit.

We report a search for gravitational waves from the inspiral, merger and ringdown of binary black holes (BBH) with total mass between 25 and 100 solar masses, in data taken at the LIGO and Virgo observatories between July 7, 2009 and October 20, 2010. The maximum sensitive distance of the detectors over this period for a (20,20)M coalescence was 300 Mpc. No gravitational wave signals were found. We thus report upper limits on the astrophysical coalescence rates of BBH as a function of the component masses for non-spinning components, and also evaluate the dependence of the search sensitivity on component spins aligned with the orbital angular momentum. We find an upper limit at 90% confidence on the coalescence rate of BBH with non-spinning components of mass between 19 and 28 M of 3.3 × 10 -7 mergers Mpc -3 yr -1 .

Compact binary systems with neutron stars or black holes are one of the most promising sources for ground-based gravitational-wave detectors. Gravitational radiation encodes rich information about source physics; thus parameter estimation and model selection are crucial analysis steps for any detection candidate events. Detailed models of the anticipated waveforms enable inference on several parameters, such as component masses, spins, sky location and distance, that are essential for new astrophysical studies of these sources. However, accurate measurements of these parameters and discrimination of models describing the underlying physics are complicated by artifacts in the data, uncertainties in the waveform models and in the calibration of the detectors. Here we report such measurements on a selection of simulated signals added either in hardware or software to the data collected by the two LIGO instruments and the Virgo detector during their most recent joint science run, including a ''blind injection'' where the signal was not initially revealed to the collaboration. We exemplify the ability to extract information about the source physics on signals that cover the neutron-star and black-hole binary parameter space over the component mass range 1 M -25 M and the full range of spin parameters. The cases reported in this study provide a snapshot of the status of parameter estimation in preparation for the operation of advanced detectors.

We have searched for gravitational waves from coalescing low mass compact binary systems with a total mass between 2M and 35M and a minimum component mass of 1M using data from the first year of the fifth science run of the three LIGO detectors, operating at design sensitivity. Depending on the mass, we are sensitive to coalescences as far as 150 Mpc from the Earth. No gravitational-wave signals were observed above the expected background. Assuming a population of compact binary objects with a Gaussian mass distribution representing binary neutron star systems, black hole-neutron star binary systems, and binary black hole systems, we calculate the 90% confidence upper limit on the rate of coalescences to be 3:9 Â 10 À2 yr À1 L À1 10 , 1:1 Â 10 À2 yr À1 L À1 10 , and 2:5 Â 10 À3 yr À1 L À1 10 , respectively, where L 10 is 10 10 times the blue solar luminosity. We also set improved upper limits on the rate of compact binary coalescences per unit blue-light luminosity, as a function of mass.

Long gamma-ray bursts (GRBs) have been linked to extreme core-collapse supernovae from massive stars. Gravitational waves (GW) offer a probe of the physics behind long GRBs. We investigate models of long-lived (∼ 10-1000 s) GW emission associated with the accretion disk of a collapsed star or with its protoneutron star remnant. Using data from LIGO's fifth science run, and GRB triggers from the Swift experiment, we perform a search for unmodeled long-lived GW transients. Finding no evidence of GW emission, we place 90% confidence level upper limits on the GW fluence at Earth from long GRBs for three waveforms inspired by a model of GWs from accretion disk instabilities. These limits range from F < 3.5 ergs cm -2 to F < 1200 ergs cm -2 , depending on the GRB and on the model, allowing us to probe optimistic scenarios of GW production out to distances as far as ≈ 33 Mpc. Advanced detectors are expected to achieve strain sensitivities 10× better than initial LIGO, potentially allowing us to probe the engines of the nearest long GRBs.

We present the results of a weakly modeled burst search for gravitational waves from mergers of non-spinning intermediate mass black holes (IMBH) in the total mass range 100-450 M and with the component mass ratios between 1:1 and 4:1. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the IMBH mergers as a function of the component masses. In the most efficiently detected bin centered on 88 + 88 M , for non-spinning sources, the rate density upper limit is 0.13 per Mpc 3 per Myr at the 90% confidence level.

We present a rigorous formal framework for Prime-Resonant Universal Translation and Non-Local Communication (PR-UTC). Central to the system is the Keytriplet structure (K priv u , K pub u , K res u), a prime-resonant symbolic fingerprint enabling secure, entropy-conserving communication across symbolic fields. We define the Resonance Field Initialization Operator R, the Symbolic Projection Operator P, the Key Evolution Operator U (∆t), and formalize Session Field Evolution Equations governing dynamic symbolic collapse and message decoding. The framework models communication as symbolic field resonance rather than classical message passing, offering a fundamentally new paradigm for secure, non-local semantic interaction.

Static and time resolved Fourier transform infrared spectroscopic studies were combined with threshold temperature programmed desorption studies to examine the effects of adsorbed sulfur on the kinetics of CO desorption from Ni(100). The appearance of new desorption states upon the addition of sulfur to Ni(100) can be attributed to the occupation of four-fold hollow and modified bridge-bonded species produced by the presence of sulfur. The observed kinetics of desorption from these surfaces is very sensitive to the initial binding site distribution of the adsorbed CO. Adsorbing at 100 K without anneal leads to a reduction in the measured desorption energy, except at the highest sulfur coverages studied. Apparently, relaxation of the adsorbed phase from a nonequilibrium distribution among sites on the surface during temperature programmed desorption is incomplete, leading to stronger repulsive interactions on the average and reduced desorption energies following adsorption at low temperature.

The goal of the present work is to obtain a reliable estimate of the masses of the ground and radially excited states of fully-heavy tetraquark systems. In order to do this, we use a nonrelativistic model of tetraquarks which are assumed to be compact and consist of diquark-antidiquark pairs. This nonrelativistic model is composed of Hulthen potential, a linear confining potential and spin-spin interaction. We computed ground, first, and second radially excited cc c c and bb b b tetraquark masses. It was found that predicted masses of ground states of cc c c and bb b b tetraquarks are significantly higher than the thresholds of the fall-apart decays to the lowest allowed two-meson states. These states should be broad and are thus difficult to observe experimentally. First radially excited states are considerably lower than their corresponding (2S-2S) two-meson thresholds. We hope that our study may be helpful to the experimental search for ground and excited cc c c and bb b b tetraquark states.

We study the S-wave mass spectra of flavor exotic triply-heavy tetraquark states $$cc\bar{c}\bar{q}$$ c c c ¯ q ¯ , $$cc\bar{b}\bar{q}$$ c c b ¯ q ¯ , $$bb\bar{c}\bar{q}$$ b b c ¯ q ¯ and $$bb\bar{b}\bar{q}$$ b b b ¯ q ¯ . We adopt a diquark–antidiquark scheme to solve Schrödinger equation. The calculations are carried out in a nonrelativistic quark model with a color interaction described by a potential computed in AdS/QCD. The AdS/QCD potential model consists of a central potential which reflects short distance and large distance behaviour of QCD, spin dependent term for hyperfine splitting and a constant term. We find stable state candidates in the $$cc\bar{c}\bar{q}$$ c c c ¯ q ¯ sector whereas in the $$cc\bar{b}\bar{q}$$ c c b ¯ q ¯ , $$bb\bar{c}\bar{q}$$ b b c ¯ q ¯ and $$bb\bar{b}\bar{q}$$ b b b ¯ q ¯ sectors all the states lie above corresponding S-wave meson-meson thresholds.

presents many surprises after its discovery more than ten years ago. Understanding its properties is crucial to understand the spectrum of possible exotic mesons. In this work, X (3872) meson and its heavy quark spin symmetry (HQSS) partners (including the mesons in the bottom sector) are studied within the QCD Sum Rules approach using a current motivated by the molecular picture of X (3872). We predict four heavy partners to X (3872) and bottomonium with the masses and J PC quantum numbers. Obtained results are in good agreement with the previous studies and available experimental data within errors.

We present an example of a realistic Higgsless model that makes use of alternative SU (2) R assignments for the top and bottom quarks recently proposed by Agashe et al. which results in an enhanced custodial symmetry. Using these new representations reduces the deviations in the Zb b coupling to ∼ 4% for a wide range of parameters, while this remaining correction can also be eliminated by varying the localization parameter (bulk mass) for b r .

We consider fermions on an extra dimensional interval. We find the boundary conditions at the ends of the interval that are consistent with the variational principle, and explain which ones arise in various physical circumstances. We apply these results to higgsless models of electroweak symmetry breaking, where electroweak symmetry is not broken by a scalar vacuum expectation value, but rather by the boundary conditions of the gauge fields. We show that it is possible to find a set of boundary conditions for bulk fermions that would give a realistic fermion mass spectrum without the presence of a Higgs scalar, and present some sample fermion mass spectra for the standard model quarks and leptons as well as their resonances. * For other possibilities of utilizing extra dimensions for electroweak symmetry breaking see .

We examine new classes of GUT models where the GUT gauge group is broken by a 4D analogue of the Scherk-Schwarz mechanism. These models are inspired by "deconstructed" 5D Scherk-Schwarz orbifold models. However, no fine tuning of parameters or assumption of higher dimensional Lorentz invariance is necessary, and the number of lattice sites can be as low as just two. These models provide simple ways to solve the doublet-triplet splitting problem, changes proton decay predictions, and may provide insight into the structure of the CKM matrix. Since the number of fields in these models is finite, the corrections to the unification of gauge couplings can be reliably calculated, and as expected result only in threshold corrections to the differential running of the couplings. Our analysis also suggests new 4D models which can enjoy the benefits of orbifold models but cannot be obtained by deconstruction of a 5D model. * J. Robert Oppenheimer Fellow. * This is the analog of being a bulk field in a large N continuum limit (extra dimensional) model. † For an early example of this idea in a string setting see ref. .

We consider various constraints on Higgsless models of electroweak symmetry breaking based on a bulk SU(2) L ×SU(2) R ×U(1) B-L gauge group in warped space. First we show that the S parameter which is positive if fermions are localized on the Planck brane can be lowered (or made vanishing) by changing the localization of the light fermions. If the wave function of the light fermions is almost flat their coupling to the gauge boson KK modes will be close to vanishing, and therefore contributions to the S parameter will be suppressed. At the same time the experimental bounds on such Z ′ and W ′ gauge bosons become very weak, and their masses can be lowered to make sure that perturbative unitarity is not violated in this theory before reaching energies of several TeV. The biggest difficulty of these models is to incorporate a heavy top quark mass without violating any of the experimental bounds on bottom quark gauge couplings. In the simplest models of fermion masses a sufficiently heavy top quark also implies an unacceptably large correction to the Zb b vertex and a large splitting between the KK modes of the top and bottom quarks, yielding large loop corrections to the T -parameter. We present possible directions for model building where perhaps these constraints could be obeyed as well.