Astrophysics
Astrophysics is a branch of astronomy that applies the principles of physics and chemistry to understand the properties and behavior of celestial objects and the universe as a whole. It encompasses the study of stars, galaxies, black holes, and the cosmic microwave background, among other phenomena. Astrophysicists use mathematical models and observational data to explore the fundamental processes governing the cosmos.
3 Key excerpts on "Astrophysics"
eBook - ePubAn Illustrated History of Science
From Agriculture to Artificial Intelligence
- Mary Cruse(Author)
- 2019(Publication Date)
- Arcturus(Publisher)
...Chapter 13 Physics ‘One cannot help but be in awe when he contemplates the mysteries of eternity, of life, of the marvellous structure of reality.’ – ALBERT EINSTEIN (1879–1955), THEORETICAL PHYSICIST I t is sometimes said that physics is the purest form of science, focused as it is on the fundamental laws of nature. The study of energy, matter and the interaction between the two, physics is all about asking the big questions, such as: ‘what is matter made of?’ and ‘what causes matter to behave in the way that it does?’. While the study of physics has a history that spans millennia, there’s still a lot left to learn. The classical physics established by scientific giants such as Galileo Galilei and Isaac Newton looks very different from the modern physics of Albert Einstein, Max Planck and their contemporaries, but both are united by the same desire to understand the basic properties of nature. This is the story of how scientists have worked to unpick the mysteries of the universe, and how we’ve discovered that the physical world is more intricate than we ever imagined. Over 2,000 years ago, Democritus proposed that the world was composed of atoms. Galileo’s famous thought experiment involved dropping objects from the Leaning Tower of Pisa. The Roots of Physics The early history of physics is intimately connected with the development of other scientific fields, such as philosophy, mathematics and astronomy. A recognisable form of the discipline began in Ancient Greece, where scholars were fascinated by the big questions that characterise physics, and worked to create theories of the universe and matter. But the story really got going in late 16th-century Italy. Here, polymath Galileo Galilei set the foundations for classical mechanics – the physics of the motion of bodies – with his famous thought experiment...
eBook - ePub- Mel Thompson(Author)
- 2012(Publication Date)
- Teach Yourself(Publisher)
...9 Cosmology In this chapter you will: • consider the ability of science to describe the origins and nature of the universe • examine the attempt to achieve a single explanatory theory • explore the human perspective on the universe. Understanding the nature of the universe as a whole has always been a central quest for both science and philosophy. As we saw in Chapter 2, the rise of modern science, with its emphasis on observation and experiment and its use of mathematics, promoted a new approach to astronomy. As we look at the work of Copernicus, Galileo, Kepler, Newton and others, we see both the quest to understand the structure of the universe, but more specifically to discover the laws of physics which would account for the movement of bodies, both heavenly and terrestrial. In cosmology, there are two interrelated sets of questions: 1 The first question What is the structure of the universe? How did it originate? What is its future? How did it develop its present form? By what physical laws can we understand its workings? Questions of this sort have led us from the Ptolemaic Earth-centred universe, through Copernicus to Newton, and on to the modern image of the world expanding outwards for the last 15 billion years from a spacetime singularity. They are concerned with order, structure and the process of development. 2 The second question What is the simplest, most basic and most general thing we can say about reality? What lies beneath the multiplicity of what we see? Questions of this kind started when Thales speculated that the world was essentially composed of water, and the atomists tried to find the basic building blocks of physical reality. They were implied within the world of Newtonian physics by the quest for ever more general and comprehensive laws of nature...
eBook - ePubThe Sense of Self
Perspectives from Science and Zen Buddhism
- Richard W. Sears(Author)
- 2016(Publication Date)
- Palgrave Macmillan(Publisher)
...On average, 60 tons of meteoritic dust falls to Earth every day, and about two trillion tons of material has fallen over the last billion years (Kelly 2016). Astronomy teaches us that we are truly all interconnected, not only with each other, but with everything else in the universe. Just as we consider people who share our genes family, we share the same atoms and molecules with everything that exists. As Carl Sagan (1980) said, we are stardust. We rely on astronomical phenomena for our very existence. We ride on a spaceship known as the Earth through a cold dark emptiness we call space. We rely on the sun for our daily existence, on its warmth, on its energy, on its light. We could no more survive without the sun than we could survive without a heart. In that sense, we could literally say that the sun is as much a part of us as our own heartbeats. We are the universe observing itself from the point we call “I” (Sagan 1980 ; Watts 1966). Physics Originally, astronomy was intertwined with astrology. Physics came along as a way to study matter, motion, energy, and other phenomena in a scientific manner, in order to distinguish beliefs and tradition from what could be empirically known and predicted (Knight 2017 ; Morrison 2015). Ancient peoples knew that the stars and planets moved with regularity, but many ideas were put forth as to why that happened, most of them based on beliefs in divine interventions. After early scientists like Galileo Galilei, Johannes Kepler, and Isaac Newton came along in the sixteenth and seventeenth centuries, motion was studied scientifically, and mathematical formulas were created that could perfectly predict the motions of falling apples, the moon falling around the Earth, and the orbits of the planets (Galilei and Seeger 1966 ; Kepler and Baumgardt 1951 ; Newton 1995). Before Newton’s time, motion was thought to be different on Earth than in the heavens...
