Direct Photon Production in High-Energy Heavy Ion Collisions within the Integrated Hydrokinetic Model

The results on description of direct photon yields, transverse momentum spectra, and flow harmonics, measured in ultrarelativistic heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) for different collision centrality classes, analyzed within the Integrated Hydrokinetic Model (iHKM) are reviewed. The iHKM simulation results, corresponding to the two opposite approaches to the matter evolution treatment at the final stage of the system’s expansion within the model, namely, the chemically equilibrated and the chemically frozen evolution, are compared. The so-called “direct photon puzzle” is addressed, and its possible solution, suggesting the account for additional photon emission at confinement, is considered.

Analysis of the Internal Structure of Hadrons Using Direct Photon Production

Achieving a precise description of the internal structure of hadrons is crucial for deciphering the hidden properties and symmetries of fundamental particles. It is a hard task since there are several bottlenecks in obtaining theoretical predictions starting from first principles. In order to complement highly accurate experiments, it is necessary to use ingenious strategies to impose constraints from the theory side. In this article, we describe how photons can be used to unveil the internal structure of hadrons. We explore how to describe NLO QCD plus LO QED corrections to hadron plus photon production at colliders and discuss the impact of these effects on the experimental measurements.

A proposal for an electrical connection between the gravitational field and light

Based on well-established equations, we provide evidence of an electrical connection between the gravitational field and light. Each is modeled using the inductance‐capacitance ( <mml:math display="inline"> <mml:mrow> <mml:mi>L</mml:mi> <mml:mi>C</mml:mi> </mml:mrow> </mml:math> ) circuit as the building block. A proposed direct photon force (not a pressure and not by means of a force carrier), the relationship between the speed of light and gravity, the frequency and wavelength of gravitational waves, gravitational redshift, the trajectory of planets around the sun, and equations of plane electromagnetic waves may all be expressed with the assistance of an ideal (no resistance) <mml:math display="inline"> <mml:mrow> <mml:mi>L</mml:mi> <mml:mi>C</mml:mi> </mml:mrow> </mml:math> circuit model of light. Each begins with the Planck‐Einstein relationship. Each suggests that gravity and electromagnetism interact directly through fluctuating electrical and magnetic fields from both sources. With this perspective Einstein's concept of the warping of spacetime may not be needed to explain gravitation.