Do We Manipulate Photons or Diffractive EM Waves to Generate Structured Light?

In the domain of light emissions, quantum mechanics has been an immensely successful guiding tool for us. In the propagation of light and optical instrument design, Huygens-Fresnel diffraction integral (HFDI) (or its advanced versions) and Maxwell’s wave equation are continuing to be the essential guiding tools for optical scientists and engineers. In fact, most branches of optical science and engineering, like optical instrument design, image processing, Fourier optics, Holography, etc., cannot exist without using the foundational postulates behind the Huygens-Fresnel diffraction integral. Further, the field of structured light is also growing where phases and the state of polarizations are manipulated usually with suitable classical macro-devices to create wave fronts that restructured through light-matter interactions through these devices. Mathematical modeling of generating such complex wave fronts generally follows classical concepts and classical macro tools of physical optics. Some of these complex light beams can impart mechanical angular momentum and spin-like properties to material particles inserted inside these structured beams because of their electromagnetic dipolar properties and/or structural anisotropy. Does that mean these newly structured beams have acquired new quantum properties without being generated through quantum devices and quantum transitions? In this chapter, we bridge the classical and quantum formalism by defining a hybrid photon (HP). HP is a quantum of energy, hν, at the initial moment of emission. It then immediately evolves into a classical time-finite wave packet, still transporting the original energy, hν, with a classical carrier frequency ν (oscillation of the E-vector). This chapter will raise enquiring questions whether all these observed “quantum-like” behaviors are manifestations of the joint properties of interacting material particles with classical EM waves or are causal implications of the existence of propagation of “indivisible light quanta” with exotic properties like spin, angular momentum, etc

Differentiating the Superposition Principle from the Measurable Superposition Effects in Interferometry

The physical interaction processes behind the emergence of dark and bright fringes registered by the detectors at the output of optical interferometers is explained. This knowledge should be helpful to interferometrists to make better physical interpretations of their data. The belief in mysterious “interference of single indivisible photon” will disappear once we recognize that the spatial or temporal energy re-distributions are generated by the physical transformation experienced by the detecting molecules drawing energy from all the light beams. The molecules could be photodetectors at the interferometer output, or the beam combining dielectric boundary. The superposition principle (SP), represented by the linear mathematical sum of two or more wave amplitudes, does not represent an observable phenomenon. The superposition effect (SE), represented by the non-linear square modulus of the joint dipolar stimulation of the detectors by all the superposed waves, is observable. We present two laboratory experiments to clarify these points. Both classical beam combiners and quantum detectors are capable of generating superposition fringes of intensity variations. The logic of “quantumness” of light is narrowly relevant only when a quantum detector deciphers the fringes; it is not valid for classical beam combiners. We will also discuss “entanglement” based on these experiments

Time-Gating Processes in Intra-Cavity Mode-Locking Devices Like Saturable Absorbers and Kerr Cells

Photons are non-interacting entities. Light beams do not interfere by themselves. Light beams constituting different laser modes (frequencies) are not capable of re-arranging their energies from extended time-domain to ultra-short time-domain by themselves without the aid of light-matter interactions with suitable intra-cavity devices. In this paper we will discuss the time-gating properties of intra-cavity "mode-locking" devices that actually help generate a regular train of high energy wave packets

Exploring Divisibility and Summability of 'Photon' Wave Packets in Nonlinear Optical Phenomena

Formulations for second and higher harmonic frequency up and down conversions, as well as multi photon processes directly assume summability and divisibility of photons. Quantum mechanical (QM) interpretations are completely congruent with these assumptions. However, for linear optical phenomena (interference, diffraction, refraction, material dispersion, spectral dispersion, etc.), we have a profound dichotomy. Most optical engineers innovate and analyze all optical instruments by propagating pure classical electromagnetic (EM) fields using Maxwell s equations and gives only lip-service to the concept "indivisible light quanta". Further, irrespective of linearity or nonlinearity of the phenomena, the final results are always registered through some photo-electric or photo-chemical effects. This is mathematically well modeled by a quadratic action (energy absorption) relation. Since QM does not preclude divisibility or summability of photons in nonlinear & multi-photon effects, it cannot have any foundational reason against these same possibilities in linear optical phenomena. It implies that we must carefully revisit the fundamental roots behind all light-matter interaction processes and understand the common origin of "graininess" and "discreteness" of light energy

A Deeper Look at the Fundamentals of Heterodyne Detection Requirements

We generally accept the experimentally observed criteria for heterodyne detections that the two waves that are mixed must (i) be collinear, (ii) have matched wave fronts and (iii) cannot be orthogonally polarized. We have not found in the literature adequate physical explanations for these requirements. The purpose of this paper is to find deeper physical understanding of the coherent heterodyne detection processes that could lead to better coherent laser radar system designs1. We find that there are a number of unresolved paradoxes in classical and quantum optics regarding the definitions and understanding of the "interference" and "coherence" properties of light, which are attributed as essentially due to inherent properties of the EM waves. A deeper exploration indicates that it is the various quantum mechanical properties of the detecting material dipoles that make light detectable (visible, or measurable) to us. Accordingly, all the properties that we generally attribute to only light, are in reality manifestations of collective properties of dipole-light interactions. "Interference" and "coherence" can be better understood in terms of this mutual interaction, followed by energy absorption by the dipoles from EM wave fields, manifesting in some measurable transformation of the detecting dipoles. Light beams do not interfere by themselves. The superposition effects due to light beams become manifest through the response characteristics of the detecting dipoles. In this paper, we will show some preliminary expe rimental results that clearly demonstrate that the heterodyning wave fronts have quantitative degradation in signal generation as the angle between them deviates from perfect collinearity. Subsequently, we will propose a hypothesis for this behavior. We will present experimental data establishing that the so called incoherent light can be detected through heterodyne mixing as long as the pulse length contained in the "incoherent" light is longer than the response time of the detector. We will also present a correspondingly better interpretation of two distinguishable coherence properties, temporal coherence and spectral coherence. Our investigation provides a deeper insight into how to rela x various system requirements for heterodyne detection and accordingly develop systems that are simpler, more reliable and lower in cost. Also, we believe that engineering of detector architecture by appropriately modifying dipole behavior using emerging nanotechnology to optimize heterodyne efficiency will be advantageous

Can the Hypothesis 'Photon Interferes only with Itself' be Reconciled with Superposition of Light from Multiple Beams or Sources?

Any superposition effect as measured (SEM) by us is the summation of simultaneous stimulations experienced by a detector due to the presence of multiple copies of a detectee each carrying different values of the same parameter. We discus the cases with light beams carrying same frequency for both diffraction and multiple beam Fabry-Perot interferometer and also a case where the two superposed light beams carry different frequencies. Our key argument is that if light really consists of indivisible elementary particle, photon, then it cannot by itself create superposition effect since the state vector of an elementary particle cannot carry more than one values of any parameter at the same time. Fortunately, semiclassical model explains all light induced interactions using quantized atoms and classical EM wave packet. Classical physics, with its deeper commitment to Reality Ontology, was better prepared to nurture the emergence of Quantum Mechanics and still can provide guidance to explore nature deeper if we pay careful attention to successful classical formulations like Huygens-Fresnel diffraction integral

Are Electrons Oscillating Photons, Oscillating “Vacuum," or Something Else? The 2015 Panel Discussion: An Unprecedented Engineering Opportunity: A Dynamical Linear Theory of Energy as Light and Matter

Platform: What physical attributes separate EM waves, of the enormous band of radio to visible to x-ray, from the high energy narrow band of gamma-ray? From radio to visible to x-ray, telescopes are designed based upon the optical imaging theory; which is an extension of the Huygens-Fresnel diffraction integral. Do we understand the physical properties of gamma rays that defy us to manipulate them similarly? One demonstrated unique property of gamma rays is that they can be converted to elementary particles (electron and positron pair); or a particle-antiparticle pair can be converted into gamma rays. Thus, EM waves and elementary particles, being inter-convertible; we cannot expect to understand the deeper nature of light without succeeding to find structural inter-relationship between photons and particles. This topic is directly relevant to develop a deeper understanding of the nature of light; which will, in turn, help our engineers to invent better optical instruments

Causal physics: photons by non-interactions of waves

A Causal Photon Model for Optical Scientists & Engineers Causal Physics: Photons by Non Interactions of Waves redefines the mathematical Superposition Principle as an operational Superposition Effect; which is the measurable physical transformation experienced by a detector due to stimulations induced by multiple waves simultaneously acting on the detecting dipoles. This light-matter interaction process driven model emerges naturally by incorporating the observed properties, Non-Interaction of Waves (NIW) and quantized photo detectors needing to fill up their "quantum-cups" with the required quantity of energy from all the stimulating waves around it. By not incorporating this NIW-property explicitly, quantum mechanics failed to extract various embedded realities in the theory while incorporated unnecessary hypotheses like wave-particle duality. The book utilizes this NIW-property to explain all the major optical phenomena (diffraction, spectrometry, coherence.) without using any self-contradictory hypotheses that are prevalent now. An Unconventional Book for All Physicists The book redefines the old ether (constituting the space) as a stationary Complex Tension Field (CTF), holding all the energy of the universe (no need for Dark Energy of Dark Matter). CTF sustains perpetually propagating EM waves as its linear excitations and the particles as self-looped localized resonant non-linear excitations. Tensions are identified by Maxwell, then the velocities of emitting and detecting atoms through the CTF contribute to the Doppler shifts separately. This calls for re-visiting physical processes behind Hubble Redshift and hence Expanding Universe. Novel Strategy for All Critical Thinkers: Visualize the Invisibles The success of the book derives from a novel thinking strategy of visualizing the invisible interaction processes, named as Interaction Process Mapping Epistemology (IPM-E). This is over and above the prevailing strategy of Measurable Data Modeling Epistemology (MDM-E). The approach inspires the next generation of physicists to recognizing that the "foundation of the edifice of physics" has not yet been finalized. IPM-E will stimulate more of us to become technology innovators by learning to emulate the ontologically real physical processes in nature and become more evolution congruent. Critical thinkers without expertise in optical science and engineering, will appreciate the value of the content by reading the book backward, starting from Ch.12; which explains the critical thinking methodology besides giving a very brief summary of the contents in the previous chapters. Establishes that abandoning the wave-particle-duality actually allows us to extract more realities out of quantum mechanics. Illustrates how the discovery of the NIW-property profoundly impacts several branches of fundamental physics, including Doppler effect and hence the cosmological red shift Summarizes that many ad hoc hypotheses from physics can be removed, a la Occam’s razor, while improving the reality and comprehension of some of the current working theories Demonstrates that our persistent attempts to restore causality in physical theories will be guided by our capability to visualize the invisible light matter interaction processes that are behind the emergence of all measurable data Draws close attention to the invisible but ontological interaction processes behind various optical phenomena so we can emulate them more efficiently and knowledgably in spite of limitations of our theories Designed as a reference book for general physics and philosophy, this optical science and engineering book is an ideal resource for optical engineers, physicists, and those working with modern optical equipment and high precision instrumentation