We study the intrinsic $$T\overline{T }$$ deformation of boundary conformal field theories from the viewpoint of boundary Ward identities and holographic realizations. We formulate the deformation through the mixed asymptotic variational principle in AdS , which gives the standard quadratic trace relation for the renormalized stress tensor without taking a finite cutoff surface as the definition of the theory.

China

Feiyu Deng

Boundary constraints and geometric realizations in holographic $$T\overline{T }$$ -deformed BCFT

In this paper, we study the dynamical connection between the surface growth scheme and the conformal field theory with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mover accent="true"><mi>T</mi><mo stretchy="false">¯</mo></mover></math> deformation. By utilizing the extended one-shot entanglement distillation tensor network, we find that the iterative growth, i.e., radial evolution of homogenous and isotropic bulk minimal surfaces in asymptotically anti–de Sitter spacetime can be mapped to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mover accent="true"><mi>T</mi><mo stretchy="false">¯</mo></mover></math> operator flow driven by the deformation parameter. Our results show that the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mover accent="true"><mi>T</mi><mo stretchy="false">¯</mo></mover></math> deformation can provide a dynamical mechanism for the surface growth in asymptotically anti–de Sitter spacetime, which may shed light on reconstructing bulk gravitational dynamics from the surface growth scheme.

Hao-Chun Liang

Jia-Rui Sun

Yuan Sun

Surface growth scheme for bulk reconstruction and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mover accent="true"><mi>T</mi><mo stretchy="false">¯</mo></mover></math> deformation

We use numerical minimization of the lattice action of trace-deformed Yang-Mills theory on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi mathvariant="double-struck">T</mi><mn>4</mn></msup></math> with twisted boundary conditions to find the classical minimum action configurations of fractional topological charge. We vary the twists and ratios of torus periods to interpolate between different <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi mathvariant="double-struck">R</mi><mrow><mn>4</mn><mo>−</mo><mi>k</mi></mrow></msup><mo>×</mo><msup><mi mathvariant="double-struck">T</mi><mi>k</mi></msup></math> geometries. This allows us to see how the corresponding minimum action saddle point configurations—monopole-instantons (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>k</mi><mo>=</mo><mn>1</mn></math>), center vortices (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>k</mi><mo>=</mo><mn>2</mn></math>), and fractional instantons (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>k</mi><mo>=</mo><mn>3</mn></math>, 4)—morph into each other. We also study how the transition between them depends on the presence of a deformation potential. In particular, we argue that the recent analytic picture of chains of monopole-instantons collimating their flux into center-vortex sheets, while technically relying on the deformation potential, also holds in pure Yang-Mills theory, for tori whose shape causes the Abelianization due to the deformation to align with the one due to the twists. Our results also indicate that with nonzero deformation potential, some transitions between different minimal-action fractional charge configurations may be discontinuous and involve level crossing.

Canada

Benjamin Dobozy

Erich Poppitz

Metamorphosis of fractional instantons on a twisted <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi mathvariant="double-struck">T</mi></mrow><mrow><mn>4</mn></mrow></msup></mrow></math> with a double-trace deformation: A numerical study

A central difficulty in the physics of traversable wormholes is the requirement of exotic matter, which arises from the violation of the null energy condition within classical general relativity. This motivates the study of modified gravitational frameworks and quantum-gravitational corrections that collectively reshape the effective stress-energy sector. In this work, we develop a unified construction combining three physically well-motivated ingredients: noncommutative geometry (NCG), the generalized uncertainty principle (GUP), and <italic>f</italic>( <italic>R, T</italic>) modified gravity with <math altimg='si15.svg'><mrow><mi>f</mi><mo>(</mo><mi>R</mi><mo>,</mo><mi>T</mi><mo>)</mo><mo>=</mo><mi>R</mi><mo linebreak='goodbreak'>+</mo><mn>2</mn><mi>&#955;</mi><mi>T</mi></mrow></math>. We adopt the matter Lagrangian <math altimg='si16.svg'><mrow><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo linebreak='goodbreak'>=</mo><mo>&#8722;</mo><mi>&#961;</mi></mrow></math> and derive the corresponding modified field equations carefully, specifying the explicit form of the effective stress-energy tensor. The NCG Gaussian matter distribution regularises the source profile over a minimal length scale <math altimg='si17.svg'><msqrt><mi>&#952;</mi></msqrt></math> and may reduce the amount of exotic matter required near the throat, while the GUP introduces quantum-gravitational corrections to the energy density and pressure at sub-Planckian scales. We perform a complete derivation of the wormhole shape function, writing it as <math altimg='si18.svg'><mrow><mi>b</mi><mrow><mo>(</mo><mi>r</mi><mo>)</mo></mrow><mo linebreak='goodbreak'>=</mo><msub><mi>b</mi><mrow><mrow><mi mathvariant='normal'>N</mi></mrow><mi>C</mi><mi>G</mi></mrow></msub><mrow><mo>(</mo><mi>r</mi><mo>)</mo></mrow><mo linebreak='goodbreak'>+</mo><msub><mi>b</mi><mrow><mrow><mi mathvariant='normal'>G</mi></mrow><mi>U</mi><mi>P</mi></mrow></msub><mrow><mo>(</mo><mi>r</mi><mo>)</mo></mrow></mrow></math>, where each contribution is obtained through an explicit integration of the corresponding source term. The throat conditions, flare-out criterion, and asymptotic flatness are verified analytically, and the key limiting cases <italic>&#946;</italic>&#8239;&#8594;&#8239;0, <italic>&#955;</italic>&#8239;&#8594;&#8239;0, and <italic>&#952;</italic>&#8239;&#8594;&#8239;0 are checked for consistency. An analysis of the null energy condition shows that the NEC violation is spatially localised near the throat owing to the Gaussian suppression provided by the NCG matter distribution, and the volume integral quantifier is evaluated with the <italic>f</italic>( <italic>R, T</italic>) coupling included explicitly. The effective potential for axial perturbations is derived and used to compute the gravitational wave echo time delay, which provides potential phenomenological signatures relevant for future gravitational-wave echo searches.

Azerbaijan

Pakistan

Allah Ditta

Noncommutative wormholes with generalized uncertainty principle in <italic>f</italic>( <italic>R, T</italic>) gravity: Energy conditions and gravitational wave echo time delay

We employ the massive gravity approach to stress-tensor deformations in a variety of scenarios, obtaining novel results and establishing new connections. Starting with perturbation theory, we show that the addition of tr$\textit{T}$ + Λ to $$ T\overline{T} $$ can be recovered and we construct the deformed action of an interacting non-abelian spin-1 along with spin-1/2 seed model, extending previous findings. As a result, a set of algebraic properties for certain hypergeometric functions is derived, allowing us to initiate the algebraic study of special functions directly via stress-tensor deformations and massive gravity. Moreover, we sharpen the connection between the trace-flow equation and the local renormalization group in any dimension. In $\textit{d}$ > 2, the usual initial condition for the coupling leads to a potential known as ghost-free, minimal massive gravity. Upon expansion around the reference background, we retrieve Fierz-Pauli at leading order, matching the random geometry and holographic approaches. At the same time, we demonstrate that a change of coordinates interpretation is possible for the corresponding operator, which we verify with a simple example. Finally, we study the family of (tr$\textit{T}$) deformations advancing earlier work, and illustrate how the massive gravity description of non-linear electrodynamics can be incorporated in our framework.

Iceland

Alexia Nix

Evangelos Tsolakidis

Massive gravity applications for $$ T\overline{T} $$ deformations

A search is presented for a light charged Higgs boson H in top quark pair production ( $$ \mathrm{t}\overline{\mathrm{t}} $$ ), where one of the top quarks decays to an H and a bottom quark, while the other decays to a W boson and a bottom quark. The H is assumed to decay into a charm and a strange quark, whereas the W boson decays into a charged lepton (electron or muon) and a neutrino. Results are reported based on proton-proton collision data at $$ \sqrt{s}=13 $$ TeV, corresponding to an integrated luminosity of 138 fb . The analysis probes H masses in the range 40 to 160 GeV using the invariant mass spectrum of the two light jets, where light jets are defined as jets that do not satisfy the bottom quark tagging requirement. The observed yield is found to be consistent with standard model predictions. Upper limits are set on the branching fraction ℬ(t → H b), with values in the range of 0.07–1.12% (0.12–1.20% expected) at 95% confidence level, under the assumption that ℬ(H → cs) = 100%. These are the first direct limits on charged Higgs bosons produced in top quark decays for masses between 40 and 50 GeV, and the most stringent limits to date in the 70–110 GeV range.

Armenia

A. Hayrapetyan

V. Makarenko

A. Tumasyan

Austria

W. Adam

L. Benato

T. Bergauer

M. Dragicevic

P. Hussain

M. Jeitler

N. Krammer

A. Li

D. Liko

M. Matthewman

J. Schieck

R. Schöfbeck

M. Shooshtari

M. Sonawane

N. Van Den Bossche

W. Waltenberger

C.E. Wulz

Belgium

T. Janssen

H. Kwon

D. Ocampo Henao

T. Van Laer

P. Van Mechelen

D. Ahmadi

J. Bierkens

N. Breugelmans

J. D’Hondt

S. Dansana

A. De Moor

M. Delcourt

C. Gupta

F. Heyen

Y. Hong

P. Kashko

S. Lowette

I. Makarenko

S. Nandakumar

S. Tavernier

M. Tytgat

G. Van Onsem

S. Van Putte

D. Vannerom

T. Wybouw

A. Beshr

B. Bilin

F. Caviglia Roman

B. Clerbaux

A. Das

I. De Bruyn

G. De Lentdecker

E. Ducarme

H. Evard

L. Favart

A. Khalilzadeh

A. Malara

M. Shahzad

A. Sharma

L. Thomas

M. Vanden Bemden

C. Vander Velde

P. Vanlaer

F. Zhang

A. Cauwels

M. De Coen

D. Dobur

C. Giordano

G. Gokbulut

K. Kaspar

D. Kavtaradze

D. Marckx

K. Skovpen

A. Tomaru

J. Linden

J. Vandenbroeck

H. Aarup Petersen

S. Bein

A. Benecke

A. Bethani

G. Bruno

A. Cappati

J. De Favereau De Jeneret

C. Delaere

F. Gameiro Casalinho

A. Giammanco

A. Guzel

V. Lemaitre

J. Lidrych

P. Malek

S. Turkcapar

Brazil

G. Alves

M. Barroso Ferreira Filho

E. Coelho

M. Gonçalves Sales

C. Hensel

D. Matos Figueiredo

T. Menezes De Oliveira

C. Mora Herrera

P. Rebello Teles

Search for light charged Higgs bosons decaying to charm and strange quarks in $$ t\overline{t} $$ events in proton-proton collisions at $$ \sqrt{s}=13 $$ TeV

The production of exotic hadrons <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>T</mi><mrow><mi>c</mi><mi>c</mi></mrow></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math> in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mi>p</mi></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>7</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> is compared using the parton and hadron cascade model together with the dynamically constrained phase-space coalescence model. In the simulation, the compact tetraquark state and the loose molecular state are formed in the partonic and hadronic levels, respectively. Our analysis of the transverse momentum spectra reveals a significant discrepancy between the compact state and the molecular states. Furthermore, the production asymmetry between <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>T</mi><mrow><mi>c</mi><mi>c</mi></mrow><mo>+</mo></msubsup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>T</mi><mrow><mi>c</mi><mi>c</mi></mrow><mo>−</mo></msubsup></math> is investigated. Finally, the coalescence parameters are extracted from the calculated spectra to further characterize the emission source properties. These distributions are proposed as valuable criteria for distinguishing between these states and investigating their internal structures in experimental measurements.

Hongge Xu

Tianqi Luo

Yi-Long Xie

Zhi-Lei She

Ning Yu

Zuman Zhang

Comparative study of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>T</mi><mrow><mi>c</mi><mi>c</mi></mrow></msub></math> versus <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math> production in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>p</mi><mi>p</mi></mrow></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>7</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>

M-theory geometric engineering on manifolds of special holonomy yields a rich class of novel field theories. In this paper, we construct new 3d 𝒩 = 2 and 𝒩 = 4 gauge theories, realized as mass-deformations of theories with 16 supercharges, within this framework. These arise from non-compact 8d geometries given by fibrations of ℝ /Γ over Bieberbach 4-manifolds. The existence of consistent Spin(7)-structures on the 8d spaces requires the rotational holonomy of the Bieberbach spaces to act on the Sp(1)-structure of the fibers. Furthermore, we analyze Higgsing the 7d 𝒩 = 1 ADE gauge theories induced by the action of a permutation group on the centres of the corresponding ℝ /Γ spaces. We show that this operation admits a natural interpretation in terms of nilpotent, upper-triangular, Higgsing, although it breaks supersymmetry. Supersymmetry is restored by fibering the singular geometry over a compact internal space, whose structure group is chosen to coincide with the permutation group to implement the nilpotent Higgsing. We refer to such backgrounds as T-geometries, where “T” denotes the triangular nature of the nilpotent Higgsing. Within this framework, we investigate the nilpotent Higgsing of the 3d 𝒩 = 2 and 4d 𝒩 = 1 theories, where the rotational holonomy groups of the Bieberbach spaces realize the permutation groups. We demonstrate that the Higgs branch moduli are encoded by specific elements of the Slodowy slices associated with nilpotent elements. Moreover, we demonstrate that additional elements of the same slice give rise to non-chiral charged matter under the unbroken gauge algebra. We establish that both the Higgs branch moduli and the charged matter are massless and admit a natural interpretation as localized matter.

Marwan Najjar

M-theory and T-geometry: Higgs branch moduli and charged matter

<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>p</mi><mi>t</mi></msub></math>-differential quantity <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>v</mi><mn>2</mn></msub><mrow><mo>(</mo><msub><mi>p</mi><mi>t</mi></msub><mo>)</mo></mrow></mrow></math> is meant to measure elliptic flow manifested by a dense QCD medium formed in high-energy nucleus-nucleus collisions. Elliptic flow may be referred to more neutrally as a cylindrical quadrupole component of the transverse motion of particle sources within a collision. As defined, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>v</mi><mn>2</mn></msub><mrow><mo>(</mo><msub><mi>p</mi><mi>t</mi></msub><mo>)</mo></mrow></mrow></math> relies on an implicit assumption that almost all produced particles emerge from a single source. This article describes a detailed study of the algebraic structure of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>v</mi><mn>2</mn></msub><mrow><mo>(</mo><msub><mi>p</mi><mi>t</mi></msub><mo>)</mo></mrow></mrow></math>. A procedure is developed to derive a common monopole boost (“radial flow”) value and quadrupole <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>p</mi><mi>t</mi></msub></math> spectra for several hadron species. The method is applied to <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>v</mi><mn>2</mn></msub><mrow><mo>(</mo><msub><mi>p</mi><mi>t</mi></msub><mo>)</mo></mrow></mrow></math> data for four hadron species from 2.76-TeV Pb-Pb collisions. According to available <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>v</mi><mn>2</mn></msub><mrow><mo>(</mo><msub><mi>p</mi><mi>t</mi></msub><mo>)</mo></mrow></mrow></math> data the assumption of a single dominant particle source within <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>A</mi></mrow><mtext>−</mtext><mrow><mi>A</mi></mrow></math> collisions is unjustified. Combined with a previous study of quadrupole amplitude variation for 200-GeV <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>p</mi><mtext>−</mtext><mi>p</mi></mrow></math> collisions these results demonstrate that quadrupole structure is related to a novel QCD process separate from projectile-nucleon dissociation and jet production. Given quadrupole evolution it is unlikely that a hydrodynamic description is relevant to that process.

United States

Thomas A. Trainor

Quadrupole spectra derived from 2.76-TeV Pb-Pb identified-hadron <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>v</mi><mn>2</mn></msub><mrow><mo>(</mo><msub><mi>p</mi><mi>t</mi></msub><mo>)</mo></mrow></mrow></math> data

The $$ f(T, T_G) $$ gravity theory is an extension of general relativity that incorporates the torsion scalar $$ T $$ as well as the teleparallel equivalent to the Gauss-Bonnet term $$ T_G $$ , to explore early and late time universe cosmology beyond the standard model. In this work, we obtain exact solutions of the field equations in the framework of $$ f(T, T_G) $$ gravity in the context of cosmological bouncing scenarios. For this, we explore the non-singular evolution of the universe by considering various bouncing cosmological models characterized by different scale factors such as the symmetric bounce, oscillatory bounce, superbounce, matter bounce, and singular bounce scenarios. For each scale factor model, we obtained the functional form of $$ f(T, T_G) $$ defining different ansatz like $$g(T)+h(T_G),~T_G~g(T)$$ and $$T+T_G ~g(T)$$ that satisfy the modified field equations and yields viable cosmological solutions. The analytical behaviors of the scale factor, Hubble parameter, energy density and pressure are examined to discuss the nature of the bounce and the avoidance of initial singularities. Our results demonstrate that the $$ f(T, T_G) $$ framework provides consistent and physically acceptable bouncing cosmologies capable of describing a smooth transition from contraction to expansion, thereby offering a viable alternative to inflationary models for the early universe.

Abdul Sultan

Ali Sabir

Malta

Jackson Said

Exact cosmological bouncing solutions in $$f(T,T_G)$$ gravity