For purchase of this item, please read the instructions.

Volume 15: Pages 457-461, 2002

Compositeness of the Photon, the Effective Photon Hypothesis, and Its Application to Quantum Electrodynamics

Probhas Raychaudhuri

Department of Applied Mathematics, Calcutta University, Calcutta‐700009 India

To explain the anomalous photoelectric emission and gas photoionization by a high‐intensity laser beam, a single photon model was advanced by Panarella and Raychaudhuri—the effective photon hypothesis—in which energy enhancement is proposed for a photon in a high‐intensity laser beam by E = hħω/[1 − (3.9 × 10³N_γ)/(m_ν(eV)(ω² − ω₀²))], where N_γ is the number density of the photon in the laser beam, m_ngr; is the neutrino mass, ω is the average frequency, and ω₀ is the characteristic frequency of the medium. Bernard et al. [Eur. Phys. J. D10, 141 (2002)] have initiated the search for possible quantum electrodynamics (QED) new physics in low‐energy stimulated photon‐photon scattering in vacuum. They pointed out that their work was based on Raychaudhuri's effective photon model. Bula et al. [Phys. Rev. Lett. 76, 3116 (1996)] reported the observation of nonlinear effects in Compton scattering for laser intensities around 1 × 10¹⁸ W/cm² in which up to four laser photons interact with an electron (i.e., nω₁ + e⁻ → e⁻ + ω). Again, Burke et al. [Phys. Rev. Lett. 79, 1626 (1997)] reported the evidence for a light by laser light scattering process involving only real photons (i.e., ω + nω₁ → e⁺ + e⁻). The above two experiments reported photon‐photon scattering in vacuum. But both experiments involve real electrons and positrons and they could not provide any quantitative measurement of the vacuum nonlinearity due to QED. In this paper we will show that the effective photon model can explain the above observations and predict the cross section for low‐energy (hħω « m_ec²) stimulated photon‐photon scattering in vacuum, which will be around 10⁻⁴⁸ to 10⁻⁴⁰ cm² depending on the energy of the photon (i.e., 1 eV to 100 eV), with a high‐intensity laser beam (10¹⁶ to 10¹⁹ W/cm²).

Keywords: compositeness of photon, laser beams, effective photons and their application to QED

Received: January 30, 2003; Published online: December 15, 2008