Physics 1. What is Physics 2. Nature Science 3. Science 4. Scientific Method 5. Branches of Science 6. Branches of Physics Einstein Newton 7. Branches of Applied Physics Bardeen Feynmann 2016-03-05 What is Physics • Meaning of Physics (from Ancient Greek: φυσική (phusikḗ )) is knowledge of nature (from φύσις phúsis "nature"). • Physics is the natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves. • Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy. Over the last two millennia, physics was a part of natural philosophy along with chemistry, certain branches of mathematics, and biology, but during the scientific revolution in the 17th century, the natural sciences emerged as unique research programs in their own right. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. • New ideas in physics often explain the fundamental mechanisms of other sciences, while opening new avenues of research in areas such as mathematics and philosophy. 2016-03-05 What is Physics • Physics also makes significant contributions through advances in new technologies that arise from theoretical breakthroughs. • For example, advances in the understanding of electromagnetism or nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization, and advances in mechanics inspired the development of calculus. 2016-03-05 Natural Science • Natural science is a branch of science concerned with the description, prediction, and understanding of natural phenomena, based on observational and empirical evidence. Validity, accuracy, and social mechanisms ensuring quality control, such as peer review and repeatability of findings, are amongst the criteria and methods used for this purpose. • Natural science can be broken into two main branches: life science (or biological science) and physical science. Physical science is further broken down into branches, including physics, astronomy, chemistry, and earth science. All of these branches of natural science are divided into many further specialized branches (also known as fields), and each of these is known as a "natural science". 2016-03-05 Natural Science • In Western society's analytic tradition, the empirical and especially natural sciences use tools from formal sciences, such as mathematics and logic, converting information about nature into measurements which can be explained as clear statements about the "laws of nature". The social sciences also use such methods, but rely more on qualitative research, so that they are sometimes called "soft science", whereas natural sciences, insofar as emphasizing quantifiable data produced, tested, and confirmed through the scientific method are sometimes called "hard science". • Modern natural science succeeded more classical approaches to natural philosophy, usually traced to ancient Greece. Galileo, Descartes, Francis Bacon, and Newton debated the benefits of using approaches which were more mathematical and more experimental in a methodical way. Still, philosophical perspectives, conjectures, and presuppositions, often overlooked, remain requisite in natural science. Systematic data collection, including discovery science, succeed natural history, which emerged in the 16th century by describing and classifying plants, animals, minerals, and so on. Yet today, natural history suggests observational descriptions aimed at popular 2016-03-05 audiences. Science • Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe. In an older and closely related meaning, "science" also refers to this body of knowledge itself, of the type that can be rationally explained and reliably applied. Ever since classical antiquity, science as a type of knowledge has been closely linked to philosophy. • In the West during the early modern period the words "science" and "philosophy of nature" were sometimes used interchangeably, and until the 19th century natural philosophy (which is today called "natural science") was considered a branch of philosophy. 2016-03-05 Science • In modern usage "science" most often refers to a way of pursuing knowledge, not only the knowledge itself. In the 17th and 18th centuries scientists increasingly sought to formulate knowledge in terms of laws of nature. Over the course of the 19th century, the word "science" became increasingly associated with the scientific method itself, as a disciplined way to study the natural world, including physics, chemistry, geology and biology. It is in the 19th century also that the term scientist began to be applied to those who sought knowledge and understanding of nature. • Modern science is typically subdivided into the natural sciences which study the material world, the social sciences which study people and societies, and the formal sciences like mathematics. The formal sciences are often excluded as they do not depend on empirical observations. Disciplines which use science like engineering and medicine may also be considered to be applied sciences. 2016-03-05 Scientific Method • The scientific method is a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry is commonly based on empirical or measurable evidence subject to specific principles of reasoning. • The Oxford English Dictionary defines the scientific method as "a method or procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.“ • The purpose of an experiment is to determine whether observations agree with or conflict with the predictions derived from a hypothesis. Experiments can take place in a college lab, on a kitchen table, at CERN, at the bottom of an ocean, on Mars, and so on. There are difficulties in a formulaic statement of method, however. Though the scientific method is often presented as a fixed sequence of steps, it represents rather a set of general principles. Not all steps take place in every scientific inquiry, and are not always in the same order. 2016-03-05 Scientific Method • The scientific method seeks to explain the events of nature in a reproducible way. An explanatory thought experiment or hypothesis is put forward, as explanation, using principles such as "Occam's Razor" (1.필요하지 않은 경우에까지 많은 것을 가정하면 안 된다. 2.보다 적은 수의 논리로 설명이 가능한 경우, 많은 수의 논리를 세 우지 말라.) and are generally expected to seek consilience—fitting well with other accepted facts related to the phenomena. • This new explanation is used to make falsifiable predictions that are testable by experiment or observation. The predictions are to be posted before a confirming experiment or observation is sought, as proof that no tampering has occurred. Disproof of a prediction is evidence of progress. This is done partly through observation of natural phenomena, but also through experimentation, that tries to simulate natural events under controlled conditions, as appropriate to the discipline (in the observational sciences, such as astronomy or geology, a predicted observation might take the place of a controlled experiment). Experimentation is especially important in science to help establish causal relationships (to avoid the correlation fallacy). 2016-03-05 Scientific Method 2016-03-05 Branches of Science • Scientific fields are commonly divided into two major groups: natural sciences, which study natural phenomena (including biological life), and social sciences, which study human behavior and societies. These groupings are empirical sciences, which means the knowledge must be based on observable phenomena and capable of being tested for its validity by other researchers working under the same conditions.[39] There are also related disciplines that are grouped into interdisciplinary applied sciences, such as engineering and medicine. Within these categories are specialized scientific fields that can include parts of other scientific disciplines but often possess their own nomenclature and expertise. 2016-03-05 Branches of Science • Mathematics, which is classified as a formal science, has both similarities and differences with the empirical sciences (the natural and social sciences). It is similar to empirical sciences in that it involves an objective, careful and systematic study of an area of knowledge; it is different because of its method of verifying its knowledge, using a priori rather than empirical methods. The formal sciences, which also include statistics and logic, are vital to the empirical sciences. Major advances in formal science have often led to major advances in the empirical sciences. The formal sciences are essential in the formation of hypotheses, theories, and laws, both in discovering and describing how things work (natural sciences) and how people think and act (social sciences). • Apart from its broad meaning, the word "Science" sometimes may specifically refer to fundamental