| General Physics |
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| An Introduction to Physics. Let's start with a bit of background information on the field of Physics as a whole. Physics is known as one of the natural sciences and is made up of a range of sub-fields, including Theoretical Physics, Experimental Physics, Applied Physics, Astrophysics (encompassing Cosmology), Biophysics, Geophysics and so on. In fact there are very few Scientific fields that cannot be associated with Physics fundamentally. The language of physics is generally Mathematics, which forms the basis of all physical analysis. Due to the "true or false" nature of Mathematics, that is where a given mathematical statement can only be true or false, the use of mathematics to describe Physical Phenomena forms a strong foundation for the proof or disproof of physical concepts, and thus a strong foundation for Physics in general. Very complex areas of Mathematics are very often used to describe Physical concepts and to prove or disprove theories formed by Physicists, in the area of Theoretical Physics. Progressively, these theories have to withstand rigorous experimental tests and analysis before they are accepted as "Valid" theories. Any new concept that does not withstand these tests is known as conjecture, and is generally discarded by professionals of the field. Exploitation of Physical theories and experiments forms the basis of technological developments through Applied Physics. It is then through the application of fundamental Physical Theories that the other scientific fields such as Geology, Biology and Astronomy can be further understood and/or developed. In the area of Theoretical Physics, there are now generally two fundamental Physical works, known as Classical Physics and Quantum Physics. Seperately, these two can be used to describe the Physical Universe as we understand it thus far in our existence as [possibly] intelligent anthropods. The foundations of Classical Physics were developed and published by one of the greatest scientists of all time, Isaac Newton, in his very astute paper "Principia Mathematica". In this paper [sir] Isaac Newton described the laws of physical mechanics of motion on a macroscopic scale [the observable universe]. He introduced three new laws to the Physics community, and in fact to the world community. What are the three laws? The first law can be described as "An object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an external force". His second law is described as "A force is a push or pull upon an object resulting from the objects interaction with another object. Forces only exist as a result of interaction between objects". The third law can be described by the statement "For every action, there is an equal and opposite reaction". Of course these are generalistic descriptions and the mathematics involved can be simple or very complex depending on the system involved. He also developed the area of Mathematics known as Calculus, which is a very powerful mathematical tool, albeit complicated in nature. Anyone who has studied to a mediocre level of mathematics will have came across Calculus at some point in their studies, but it is by no means an easy branch of Mathematics to master. As a graduate of Applied Physics I can say I have studied and used Calculus on uncountable occasions during my studies and I still have not mastered it and must often recap on even some of the basic rules! However, without this piece of genius, presented to us by a genius himself, I feel that a lot of Science and Engineering as we know it now would not exist. Quantum Physics is the complete opposite to Classical Physics firstly for its incompleteness and for other reasons, such that this area concerns the microscopic and sub-microscopic universe. The initial theoriy of Quantum Physics came about during the time of Albert Einstein, quite recently in fact, during the 1920's and 1930's and even now it is considered by many Physicists to be incompletely understood. More definedly, Quantum Physics is the branch of Physics that deals with discrete, invisible packets of energy called Quanta. The main ideas of Quantum Theory can be described as in the following five ideas: 1. Energy has no continuity, but comes instead in small, discrete units or packets; 2. Particles of the elements behave both as particles and waves; 3. The motion of these particles is random or chaotic; 4. It is physically impossible to know precisely both a particles position and velocity at the same time; 5. There are profoundly fundamental differences between the macroscopic world [that we live in and observe] and the Quantum Physcial world. Apart from being the most important scientific discovery in history, Quantum Physics is also probably the biggest intelligible breakthrough in human history and it is by far one of the most complex concepts that humankind has ever worked on and is still working on, right now! Its very existence as a piece of human intellect has profound Philisophical implications, and in fact was disregarded as nonsense in its initial introduction to society. Even a great Physicist like Richard Feynman (who worked on the developement of Quantum Electro-Dynamics, QED for short) did not fully understand Quantum theory. Albert Einstein himself is famous for his quote [amonst other things, such as his great work on General and Special Relativity and his award of the Nobel prize for Physics for his work on The Photoelectric Effect) which stated "God, does not play dice!" implying, I feel, that the great Architecht of the Universe would not construct the Universe using such theories of randomness or chance. But nevertheless, the Quantum Theory has withstood all these tests and is still used, as far as it is currently understood, in further Technological development. But the story does not finish there... |
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