Thesis Abstract

Abstract
Electromagnetic radiation is a form of energy that emanates from various sources, both natural and man-made, and has been a subject of growing concern due to its potential effects on Earth's environment. This research project aims to investigate the effects of electromagnetic radiation on Earth, focusing on both the natural sources such as cosmic rays and solar radiation, as well as the anthropogenic sources including power lines, electronic devices, and wireless communication systems. The study will explore the interaction of electromagnetic radiation with the Earth's atmosphere, biosphere, and geosphere, considering the impact on living organisms, ecosystems, and the overall environmental balance. Special attention will be given to the potential health effects on humans and wildlife, as exposure to electromagnetic fields has been linked to various biological responses and health risks. Furthermore, the research will investigate the role of electromagnetic radiation in climate change, considering its influence on atmospheric processes such as ionization, cloud formation, and temperature regulation. By analyzing existing data and conducting field experiments, the project aims to provide a comprehensive understanding of how electromagnetic radiation affects Earth's climate and ecological systems. The methodology will involve a combination of theoretical modeling, laboratory experiments, and field observations to assess the levels of electromagnetic radiation in different environments and their corresponding effects on biotic and abiotic components. Specialized equipment such as electromagnetic field meters, radiation detectors, and biological sensors will be used to measure and monitor the exposure levels in various settings. The findings of this research project are expected to contribute to the existing knowledge on the impacts of electromagnetic radiation on Earth and provide valuable insights for policymakers, environmental agencies, and the scientific community. By identifying the potential risks and benefits associated with different sources of electromagnetic radiation, this study aims to facilitate informed decision-making and the development of mitigation strategies to protect the environment and public health. Overall, this research project seeks to address the complex relationship between electromagnetic radiation and Earth's ecosystems, highlighting the importance of understanding and managing this form of energy to ensure a sustainable and healthy environment for current and future generations.

Thesis Overview

Electromagnetic radiation (EM radiation or EMR) is a fundamental phenomenon of electromagnetism, behaving as waves and also as particles called photons which travel through space carrying radiant energy. In a vacuum, it propagates at the speed of light, normally in straight lines. EMR is emitted and absorbed by charged particles. As an electromagnetic wave, it has both electric and magnetic field components, which synchronously oscillate perpendicular to each other and perpendicular to the direction of energy and wave propagation.

In classical physics, EMR is produced when charged particles are accelerated by forces acting on them. Electrons are responsible for emission of most EMR because they have low mass, and therefore are easily accelerated by a variety of mechanisms. Quantum processes can also produce EMR, such as when atomic nuclei undergo gamma decay, and processes such as neutral pion decay.
EMR carries energy—sometimes called radiant energy—through space continuously away from the source (this is not true of the near-field part of the EM field). EMR also carries both momentum and angular momentum. These properties may all be imparted to matter with which it interacts. When created, EMR is produced from other types of energy and it is converted to other types of energy when it is destroyed.

The electromagnetic spectrum, in order of increasing frequency and decreasing wavelength, can be divided, for practical engineering purposes, into radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays. The eyes of various organisms sense a relatively small range of frequencies of EMR near and including the visible spectrum or light. Visible light is that part of the spectrum to which human eyes respond. Higher frequencies (shorter wavelengths) have more energy in the photons, according to the well-known law E=hν, where E is the energy per photon, ν is the frequency carried by the photon, and h is Planck's constant. A single gamma ray photon carries far more energy than a single photon of visible light.

The photon is the quantum of the electromagnetic interaction, and is the basic constituent of all forms of EMR. The quantum nature of light becomes more apparent at high frequencies (thus high photon energy). Such photons behave more like particles than lower-frequency photons do.

Electromagnetic waves in free space must be solutions of Maxwell's electromagnetic wave equation. Two main classes of solutions are known, namely plane waves and spherical waves. The plane waves may be viewed as the limiting case of spherical waves at a very large (ideally infinite) distance from the source. Both types of waves can have a waveform which is an arbitrary time function (so long as it is sufficiently differentiable to conform to the wave equation). As with any time function, this can be decomposed by means of Fourier analysis into its frequency spectrum, or individual sinusoidal components, each of which contains a single frequency, amplitude, and phase. Such a component wave is said to be monochromatic. A monochromatic electromagnetic wave can be characterized by its frequency or wavelength, its peak amplitude, its phase relative to some reference phase, its direction of propagation, and its polarization.

Electromagnetic radiation is associated with EM fields that are free to propagate themselves without the continuing influence of the moving charges that produced them, because they have achieved sufficient distance from those charges. Thus, EMR is sometimes referred to as the far field. In this language, the near field refers to EM fields near the charges and current that directly produced them, as for example with simple magnets and static electricity phenomena. In EMR, the magnetic and electric fields are each induced by changes in the other type of field, thus propagating itself as a wave. This close relationship assures that both types of fields in EMR stand in phase and in a fixed ratio of intensity to each other, with maxima and nodes in each found at the same places in space.

The effects of EMR upon biological systems (and also to many other chemical systems, under standard conditions) depend both upon the radiation's power and frequency. For lower frequencies of EMR up to those of visible light (i.e., radio, microwave, infrared), the damage done to cells and also to many ordinary materials under such conditions is determined mainly by heating effects, and thus by the radiation power. By contrast, for higher frequency radiations at ultraviolet frequencies and above (i.e., X-rays and gamma rays) the damage to chemical materials and living cells by EMR is far larger than that done by simple heating, due to the ability of single photons in such high frequency EMR to damage individual molecules chemically.

OCCURRENCE AND IMPORTANCE OF ELECTROMAGNETIC RADIATION
Close to 0.01 percent of the mass/energy of the entire universe occurs in the form of electromagnetic radiation. All human life is immersed in it and modern communications technology and medical services are particularly dependent on one or another of its forms. In fact, all living things on Earth depend on the electromagnetic radiation received from the Sun and on the transformation of solar energy by photosynthesis into plant life or by biosynthesis into zooplankton, the basic step in the food chain in oceans. The eyes of many animals, including those of humans, are adapted to be sensitive to and hence to see the most abundant part of the Sun’s electromagnetic radiation—namely, light, which comprises the visible portion of its wide range of frequencies. Green plants also have high sensitivity to the maximum intensity of solar electromagnetic radiation, which is absorbed by a substance called chlorophyll that is essential for plant growth via photosynthesis.
Practically all the fuels that modern society uses—gas, oil, and coal—are stored forms of energy received from the Sun as electromagnetic radiation millions of years ago. Only the energy from nuclear reactors does not originate from the Sun.
Everyday life is pervaded by man-made electromagnetic radiation: food is heated in microwave ovens, airplanes are guided by radar waves, television sets receive electromagnetic waves transmitted by broadcasting stations, and infrared waves from heaters provide warmth. Infrared waves also are given off and received by automatic self-focusing cameras that electronically measure and set the correct distance to the object to be photographed. As soon as the Sun sets, incandescent or fluorescent lights are turned on to provide artificial illumination, and cities glow brightly with the colourful fluorescent and neon lamps of advertisement signs. Familiar too is ultraviolet radiation, which the eyes cannot see but whose effect is felt as pain from sunburn. Ultraviolet light represents a kind of electromagnetic radiation that can be harmful to life. Such is also true of X rays, which are important in medicine as they allow physicians to observe the inner parts of the body but exposure to which should be kept to a minimum. Less familiar are gamma rays, which come from nuclear reactions and radioactive decay and are part of the harmful high-energy radiation of radioactive materials and nuclear weapons.