We analyze radiative corrections to the predictions of Starobinsky-like models of inflation arising from self-interactions of the inflaton, and from its Yukawa couplings, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>y</mi></math>, to matter fermions, and dimensionful trilinear couplings, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>κ</mi></math>, to scalar fields, which could be responsible for reheating the Universe after inflation. The inflaton self-interactions are found to be of higher order in the Hubble expansion rate during inflation, and hence unimportant for CMB observations. In contrast, Einstein-frame matter couplings to an inflaton generating Starobinsky-like inflation can have significant effects on the spectral index of scalar CMB perturbations, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>n</mi><mi>s</mi></msub></math>, and on the tensor-to-scalar ratio, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>r</mi></math>. Using a renormalization-group improved analysis of the effective inflationary potential, we find that the Planck measurement of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>n</mi><mi>s</mi></msub></math> constrains the inflaton coupling to light fermions in the Einstein frame; <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>y</mi><mo>&lt;</mo><mn>4.5</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math>, corresponding to an upper limit on the reheating temperature <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>T</mi><mrow><mi>RH</mi></mrow></msub><mo>&lt;</mo><mn>2</mn><mo>×</mo><msup><mn>10</mn><mn>11</mn></msup><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>, whereas the ACT DR6 measurement of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>n</mi><mi>s</mi></msub></math> corresponds to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3.8</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup><mo>&lt;</mo><mi>y</mi><mo>&lt;</mo><mn>5.6</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1.7</mn><mo>×</mo><msup><mn>10</mn><mn>11</mn></msup><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>&lt;</mo><msub><mi>T</mi><mrow><mi>RH</mi></mrow></msub><mo>&lt;</mo><mn>2.8</mn><mo>×</mo><msup><mn>10</mn><mn>11</mn></msup><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>, while the upper limits on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>r</mi></math> provide weaker constraints. Planck data also imply a constraint on a trilinear inflaton coupling to light scalars in the Einstein frame: <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>κ</mi><mo>≤</mo><mn>4</mn><mo>×</mo><msup><mn>10</mn><mn>12</mn></msup><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>, corresponding to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>T</mi><mrow><mi>RH</mi></mrow></msub><mo>≤</mo><mn>4.2</mn><mo>×</mo><msup><mn>10</mn><mn>13</mn></msup><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>. We further present constraints on inflaton couplings to massive fermions and scalars, and analyze constraints on couplings in the Jordan frame.

CERN

United Kingdom

John Ellis

United States

Tony Gherghetta

Japan

Kunio Kaneta

Wenqi Ke

Keith A. Olive

Effects of radiative corrections on Starobinsky inflation

In this paper, we study Proca stars in asymptotically anti-de Sitter (AdS) Ellis wormholes. This study distinguishes itself from the analysis of the Proca stars in asymptotically flat spacetimes. In the AdS Ellis wormhole background, the mass of the wormhole solutions vanishes. Consequently, we employ numerical techniques to investigate in detail the impact of the cosmological constant on both the matter field and the wormhole geometry, while categorizing the solutions in accordance with the symmetries of the Proca field. The results show that when the cosmological constant decreases, not only does the characteristic spiral behavior of the Proca star solutions, namely the charge-frequency relation $\textit{Q}$– $$\omega ,$$ gradually disappear, but the throat or both sides of the wormhole may also develop a “horizon”, presenting a “black bounce” characteristic.

China

Gen Li

Chen-Hao Hao

Xin Su

Yong-Qiang Wang

Proca stars in AdS Ellis wormholes

In this paper, we present a spherically symmetric wormhole in Einstein gravity coupled with the phantom scalar field and the nonlinear electromagnetic field. Numerical results show that this solution violates the Null Energy Condition (NEC), and as the parameters change, the ADM mass of the entire spacetime changes from positive to negative. In addition, we analyze the light ring (LR) of the solution and demonstrate the astronomical observation properties. Especially when negative mass appears, the general LR will not appear, only a “special unstable LR” exists at the throat, which is caused by the repulsive effect of the negative mass on both sides of the wormhole. Finally, we draw the embedding diagram to reflect the geometric characteristics of the wormhole.

Tie-Feng Fang

Generalized Bronnikov–Ellis wormhole with nonlinear electromagnetic field

The world of particle physics was revolutionised in November 1974 by the discovery of the J/ <italic>&#968;</italic> particle, the first particle to be identified as a quarkonium state composed of charm quarks and antiquarks. The charmonium interpretation of the J/ <italic>&#968;</italic> was cemented by the subsequent observations of a spectrum of related <math altimg='si1.svg'><mover accent='true'><mrow><mi>c</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover><mi>c</mi></math> states, and finally by the discovery of charmed particles in 1976. The discovery of charmonium was followed in 1977 by the discovery of bottomonium mesons and particles containing bottom quarks. Toponium bound states of top quark and antiquarks were predicted to exist in principle but, following the discovery of the top quark in 1995, most physicists thought that its observation would have to wait for a next-generation <math altimg='si2.svg'><msup><mrow><mi>e</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>&#8722;</mo></mrow></msup></math> collider. However, in the second half of 2024 the CMS Collaboration reported an excess of events near the threshold for <math altimg='si3.svg'><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover><mi>t</mi></math> production at the LHC that is most plausibly interpreted as the lowest-lying toponium state. These are the personal recollections of an eyewitness who followed closely these 50 years of quarkonium discoveries.

Switzerland

Personal memories of 50 years of quarkonia

In this paper, we explore the properties of the Ellis-Jaffe Sum Rule (EJSR) by employing the Principle of Maximum Conformality (PMC) approach to address its perturbative part up to next-to-next-to-next-to-leading order ( <math altimg='si1.svg'><msup><mrow><mi mathvariant='normal'>N</mi></mrow><mrow><mn mathvariant='normal'>3</mn></mrow></msup><mi mathvariant='normal'>LO</mi></math>) QCD contributions. By applying the PMC, we achieve a precise perturbative QCD prediction for the EJSR, free from conventional ambiguities associated with the renormalization scale choices. Considering the presence of the <math altimg='si2.svg'><msub><mrow><mi>&#945;</mi></mrow><mrow><mi>s</mi></mrow></msub></math> Landau pole near the asymptotic scale, we incorporate the low-energy <math altimg='si2.svg'><msub><mrow><mi>&#945;</mi></mrow><mrow><mi>s</mi></mrow></msub></math> model based on analytic perturbation theory (APT) to refine the EJSR behavior in the infrared region. By combining the PMC approach with the low-energy APT model, the agreement between theoretical calculations and experimental measurements of EJSR is significantly improved, as evidenced by the reduced discrepancy from <math altimg='si3.svg'><msup><mrow><mi>&#967;</mi></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='false'>/</mo><mi>d</mi><mo>.</mo><mi>o</mi><mo>.</mo><mi>f</mi><msub><mrow><mo stretchy='false'>|</mo></mrow><mrow><mi mathvariant='normal'>Conv</mi><mo>.</mo></mrow></msub><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>1.86</mn></math> to <math altimg='si4.svg'><msup><mrow><mi>&#967;</mi></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='false'>/</mo><mi>d</mi><mo>.</mo><mi>o</mi><mo>.</mo><mi>f</mi><msub><mrow><mo stretchy='false'>|</mo></mrow><mrow><mi mathvariant='normal'>PMC</mi></mrow></msub><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>1.19</mn></math>, thereby validating the effectiveness of our approach.

Hua Zhou

Qing Yu

Xing-Gang Wu

Updated determination of Ellis-Jaffe sum rules up to N 3LO QCD corrections

We discuss the phenomenology at hadron colliders of a pseudoscalar Higgs boson <italic>A</italic>, as predicted in many extensions of the Standard Model. In particular, we highlight the aspects that makes it different from the case of a quasi-bound toponium state. We apply the discussion to the excess of <math altimg='si1.svg'><mi>t</mi><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover></math> threshold events recently observed at the LHC by the CMS collaboration <cross-ref refid='br0010' id='crf0090'>[1]</cross-ref>, which could in principle be due to either or both possibilities, although Occam's razor favours the toponium scenario. Working in an effective theory in which only an additional pseudoscalar <italic>A</italic> boson is present in the spectrum, with a mass above the <math altimg='si2.svg'><mn>2</mn><msub><mrow><mi>m</mi></mrow><mrow><mi>t</mi></mrow></msub></math> threshold and a significant coupling to top quarks, we discuss the interference between <italic>A</italic> production in the dominant gluon-fusion process <math altimg='si3.svg'><mi>g</mi><mi>g</mi><mo stretchy='false'>&#8594;</mo><mi>A</mi></math> with subsequent <math altimg='si4.svg'><mi>A</mi><mo stretchy='false'>&#8594;</mo><mi>t</mi><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover></math> decays, and the QCD continuum background, <math altimg='si5.svg'><mi>g</mi><mi>g</mi><mo stretchy='false'>&#8594;</mo><mi>t</mi><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover></math>. While this interference is absent in the case of toponium, it is essential for evaluating <italic>A</italic> production. It is difficult to resolve the peak/dip structure that it generates because of the experimental smearing of the <math altimg='si1.svg'><mi>t</mi><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover></math> invariant mass spectrum. However, by comparing the total <italic>A</italic> production rates for different integration domains of the <math altimg='si1.svg'><mi>t</mi><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover></math> invariant mass or, eventually, at different center-of-mass energies, one may be able to observe its effects. We then discuss additional mechanisms for <italic>A</italic> production in <italic>pp</italic> collisions, including loop-induced production in association with the lighter <italic>h</italic> boson, <math altimg='si6.svg'><mi>g</mi><mi>g</mi><mo stretchy='false'>&#8594;</mo><mi>h</mi><mi>A</mi></math>, and production in association with top-quark pairs, <math altimg='si7.svg'><mi>g</mi><mi>g</mi><mo stretchy='false'>/</mo><mi>q</mi><mover accent='true'><mrow><mi>q</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover><mo stretchy='false'>&#8594;</mo><mi>t</mi><mover accent='true'><mrow><mi>t</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover><mi>A</mi></math>. These mechanisms have small cross sections at the LHC, and their observation will necessitate higher luminosities or collider energies.

France

Spain

Abdelhak Djouadi

Jérémie Quevillon

Contrasting pseudoscalar Higgs and toponium states at the LHC and beyond

In this paper, we theoretically investigate gravitational lensing within the space-time framework of traversable wormholes, focusing on the combined effects of a global monopole and a cosmic string. Specifically, we examine the Ellis-Bronnikov-Morris-Thorne wormhole metric and analyze how these topological defects influence photon trajectories. By considering the weak-field limit, we derive analytical expressions for the photon deflection angle, highlighting how factors such as the wormhole throat radius, the global monopole charge, and the cosmic string influence the gravitational lensing phenomenon. We also examine the weak-field limit of lensing phenomena for a zero wormhole throat radius and derive an analytical expression for the deflection angle of photon light in this scenario.

India

Faizuddin Ahmed

Türkiye

İzzet Sakallı

Jordan

Ahmad Al-Badawi

Gravitational lensing phenomena of Ellis-Bronnikov-Morris-Thorne wormhole with global monopole and cosmic string

In this paper, we study the spherically symmetric traversable wormholes supported by a phantom field in the anti-de Sitter (AdS) asymptotic spacetime. We couple an additional complex scalar field into this wormhole spacetime and study the physical properties of this model. Despite coupling the scalar matter field, these wormholes remain massless and symmetric for reflection of the radial coordinate $$r \rightarrow -r.$$ The solution possesses a finite Noether charge , which varies as a function of frequency $$\omega $$ with changes in the cosmological constant $$\Lambda $$ and the throat size $$r_0.$$ Under specific conditions, an approximate “event horizon” will appear at the throat.

AdS Ellis wormholes with scalar field

Neutral triple gauge couplings (nTGCs) are a manifestation of new physics beyond the Standard Model (SM), as they are absent in the SM and are first generated by dimension-8 operators in the SM effective field theory (SMEFT). We study the UV completion of nTGCs in a renormalizable model with vectorlike heavy fermions. We compute the one-loop heavy fermion contributions to nTGC vertices by matching them to dimension-8 operators in the low energy limit. Such fermion loops contain either heavy fermions only or mixture of heavy fermions with light SM fermions. We find that their contributions can induce dimension-8 nTGC effective operators containing two SM Higgs-doublet fields, which are formulated with a complete set of 7 dimension-8 operators generating off-shell <math><mi>C</mi><mi>P</mi></math>-even nTGCs. We present the results in terms of SMEFT coefficients and in terms of nTGC vertices (form factors) with two on-shell gauge bosons. In the heavy-light mixing case there appear terms that cannot be accommodated by conventional parametrizations of form factors due to extra logarithmic corrections. We further discuss the implications for probing such UV dynamics via nTGCs at high-energy colliders.

Hong-Jian He

Rui-Qing Xiao

Shi-Ping Zeng

Jiaming Zheng

UV completion of neutral triple gauge couplings

We study the anomalous magnetic moment of the muon, $$g_\mu - 2 \equiv 2 a_\mu $$ <math> <mrow> <msub> <mi>g</mi> <mi>μ</mi> </msub> <mo>-</mo> <mn>2</mn> <mo>≡</mo> <mn>2</mn> <msub> <mi>a</mi> <mi>μ</mi> </msub> </mrow> </math> , in the context of supersymmetric models beyond the CMSSM, where the unification of either the gaugino masses $$M_{1,2,3}$$ <math> <msub> <mi>M</mi> <mrow> <mn>1</mn> <mo>,</mo> <mn>2</mn> <mo>,</mo> <mn>3</mn> </mrow> </msub> </math> or sfermion and Higgs masses is relaxed, taking into account the measured mass of the Higgs boson, $$m_H$$ <math> <msub> <mi>m</mi> <mi>H</mi> </msub> </math> , the cosmological dark matter density and the direct detection rate. We find that the model with non-unified gaugino masses can make a contribution $$\Delta a_\mu \sim 20 \times 10^{-10}$$ <math> <mrow> <mi>Δ</mi> <msub> <mi>a</mi> <mi>μ</mi> </msub> <mo>∼</mo> <mn>20</mn> <mo>×</mo> <msup> <mn>10</mn> <mrow> <mo>-</mo> <mn>10</mn> </mrow> </msup> </mrow> </math> to the anomalous magnetic moment of the muon, for example if $$M_{1,2} \sim 600\; \textrm{GeV}$$ <math> <mrow> <msub> <mi>M</mi> <mrow> <mn>1</mn> <mo>,</mo> <mn>2</mn> </mrow> </msub> <mo>∼</mo> <mn>600</mn> <mspace width="0.277778em"></mspace> <mtext>GeV</mtext> </mrow> </math> and $$M_3\sim 8 \; \textrm{TeV}$$ <math> <mrow> <msub> <mi>M</mi> <mn>3</mn> </msub> <mo>∼</mo> <mn>8</mn> <mspace width="0.277778em"></mspace> <mtext>TeV</mtext> </mrow> </math> . The model with non-universal sfermion and Higgs masses can provide even larger $$\Delta a_\mu \sim 24 \times 10^{-10}$$ <math> <mrow> <mi>Δ</mi> <msub> <mi>a</mi> <mi>μ</mi> </msub> <mo>∼</mo> <mn>24</mn> <mo>×</mo> <msup> <mn>10</mn> <mrow> <mo>-</mo> <mn>10</mn> </mrow> </msup> </mrow> </math> if the sfermion masses for the first and the second generations are $$ \sim 400 \; \textrm{GeV}$$ <math> <mrow> <mo>∼</mo> <mn>400</mn> <mspace width="0.277778em"></mspace> <mtext>GeV</mtext> </mrow> </math> and that of the third is $$ \sim 8 \; \textrm{TeV}$$ <math> <mrow> <mo>∼</mo> <mn>8</mn> <mspace width="0.277778em"></mspace> <mtext>TeV</mtext> </mrow> </math> . We discuss the prospects for collider searches for supersymmetric particles in specific benchmark scenarios illustrating these possibilities, focusing in particular on the prospects for detecting the lighter smuon and the lightest neutralino.

Keith Olive

Greece

Vassilis Spanos

Non-universal SUSY models, $$g_\mu -2$$ <math> <mrow> <msub> <mi>g</mi> <mi>μ</mi> </msub> <mo>-</mo> <mn>2</mn> </mrow> </math> , $$m_H$$ <math> <msub> <mi>m</mi> <mi>H</mi> </msub> </math> and dark matter