Classical and Quantum mechanics are the two main fields of mechanics in physics. Classical mechanics came a few hundred years before Quantum mechanics. Subsequently it is less accurate and less reliable then the more recent mechanic field of Quantum mechanics. Despite being outdated, Classical mechanics can still be used for many everyday problems with bigger and slower moving objects. However, when dealing with extremely fast moving or small subatomic particles a Classical approach will not produce sufficiently accurate results as was the case around the 19th century.
Difficulties with the Classical mechanics theory came right around the 19th century. First was the Ultraviolet Catastrophe. Experimental data when testing blackbody radiation was found to be inconsistent with Classical mechanics. The data showed that as the wavelength of the incoming radiation approaches zero, the amount of energy being radiated also approaches zero, whereas Classical mechanics says the emitted energy is infinite. The second difficulty with the theory was its inability to correctly describe the photoelectric effect. The photoelectric effect says that photons from a surface are released when light hits it. Classical mechanics says that electrons will be emitted from a metal by light waves with any frequency as long as the intensity of the light is strong enough, and even if it is weak over a long enough period of time electrons will eventually be emitted. The theory was proved incorrect after experiments showed that light under certain frequencies did not produce the photoelectric effect on the metal, which meant that the emitting of electrons is related not to intensity but the waves frequency.
A new string of mechanics, Quantum mechanics, was created in order to resolve the incompatibilities of Classical Mechanics. A main difference between the two fields of mechanics is the make up of the atom. In Quantum mechanics electrons in an atom are outside of the nucleus in specific orbitals around the nucleus that they can jump from one to another only when a specific energy level is reached, and can never be in-between the specific orbitals. Also Quantum mechanics says that a photon is released only when an electron jumps from a higher energy level to a lower energy level, or a higher energy orbital to a lower energy orbital. Classical mechanics, contradicting this, says that an atom is constantly emitting radiation.
Quantum mechanics describes light as both a wave and a particle, depending on the situation.
light to exist in a world devoid of color. While both allow the existence of a
The novel, Alice and Quantum Land, by Robert Gilmore is an adventure in the Quantum universe. Alice, a normal teenage girl, goes through quantum land and understands what quantum is and how it works. The quantum world is a difficult one to understand, as its nature is one of complex states of being, natures, principles, notions, and the like. When these principles or concepts are compared with the macro world, one can find great similarities and even greater dissimilarities between the world wherein electrons rule, and the world wherein human beings live. In Alice in Quantumland, author Robert Gilmore converts the original tale of Alice in Wonderland from a world of anthropomorphic creatures into the minute world of quantum mechanics, and attempts to ease the reader into this confusing world through a series of analogies (which comprise an allegory) about the principles of quantum mechanics. Through Alice’s adventure she comes across some ideas or features that contradict real world ideas. These ideas are the following: Electrons have no distinguishing spin, the Pauli Exclusion Principle, Superposition, Heisenberg Uncertainty Principle, and Interference and Wave Particle Duality.
Quantum Mechanics This chapter compares the theory of general relativity and quantum mechanics. It shows that relativity mainly concerns that microscopic world, while quantum mechanics deals with the microscopic world.
In 1905 Einstein published the Annus Mirabilis papers. These papers explained each of his four main theories; the photoelectric effect, Brownian motion, Special Relativity and Matter energy-equivalence. These four works created the foundation for modern day physics and brought a new view to space, time and matter. Brownian motion is the random movement of small particles in either a gas or a liquid caused by collisions with the particles around them. Albert Einstein came up with mathematical equations that allowed him to determine the exact size of atoms. With these equations Einstein essentially provided the first substantial evidence that atoms actually do exist. Einstein’s second paper was on the photoelectric effect. Until Einstein, the photoelectric effect went unsolved. Einstein concluded that when a photon hits a metal surface, the photoelectrons on the metals surface are emitted as certain light frequencies. Thus proving that light has quanta meaning it has packets of energy. This has brought huge technological advancements and has a lot to do with many things that surround us today. Old television used video camera tubes that required the photoelectric effect to charge the screen and transform the image...
Nature of wave: It is an electromagnetic wave as it does not necessarily require a medium for p...
Now the description of light is harder concept to grasp. We describe light by using wavelength and frequency. Wavelength would be the distance between two corresponding points on a wave. Frequency would be the number of waves that passes a point per second. For example the wavelengths of visible light such as red would be visible at seven hundred nanometers. Another example on how we describe light is to take the color green, for it to be visible it would have a wavelength of five hundred nanometers and a frequency of 6 x 10 14/s. Light can also be described on our scale as both waves and particles or packets of light called photons. The energy of a photon is proportional to the frequency. The last way we can describe light is to use the Atomic Spectra. The atomic spectra give only specific colors in a line spectrum, where each line is a specific wavelength of light. For example colored light, such as light from a neon sign would work perfectly with the atomic spectra.
Of the many counter intuitive quirks of quantum mechanics, the strangest quirk is perhaps the notion of quantum entanglement. Very roughly, quantum entanglement a phenomenon where the state of a large system cannot be described by the state of the smaller systems that compose it. On the standard metaphysical interpretation of quantum entanglement, this is taken to show that there exists emergent properties1. If this standard interpretation is correct, it seems that physics paints a far different picture of the world then commonsense leads one to believe.
This is not the intention of the use of the word in quantum physics. Quantum particles are, instead, representations of the actions and reactions of forces at the sub-atomic level. In fact, physicists are less concerned with the search for a material particle underlying all physical objects and more interested in explaining how nature works. Quantum theory is the means that enables the physicist to express those explanations in a scientific way. Modern science is based on material, experimental evidence, but if matter is non-material as the physicist's fundamental forces suggest, then it will not be able to explain what matter is.
According to the de Broglie relation and Bragg's law, a beam of 54 eV had a wavelength of 0.167 nm. The experimental outcome was 0.165 nm via the grating equation, which closely matched the predictions. Davisson and Germer's accidental discovery of the diffraction of electrons was the first direct evidence confirming de Broglie's hypothesis that particles can have wave properties as well.
Stemming from the first years of the 20th century, quantum mechanics has had a monumental influence on modern science. First explored by Max Planck in the 1900s, Einstein modified and applied much of the research in this field. This begs the question, “how did Einstein contribute to the development and research of quantum mechanics?” Before studying how Einstein’s research contributed to the development of quantum mechanics, it is important to examine the origins of the science itself. Einstein took much of Planck’s experimental “quantum theory” research and applied it in usable ways to existing science. He also greatly contributed to the establishment of the base for quantum mechanics research today. Along with establishing base research in the field, Einstein’s discoveries have been modified and updated to apply to our more advanced understanding of this science today. Einstein greatly contributed to the foundation of quantum mechanics through his research, and his theories and discoveries remain relevant to science even today.
At the atomic scale of quantum mechanics, however, measurement becomes a very delicate process. Let's say you want to find out where an electron is and where it is going (that trooper has a feeling that any electron he catches will be going faster than the local speed limit). How would you do it? Get a super high powered magnifier and look for it? The very act of looking depends upon light, which is made of photons, and these photons could have enough momentum that once they hit the electron they would change its course! It's like rolling the cue ball across a billiard table and trying to discover where it is going by bouncing the 8-ball off of it; by making the measurement with the 8-ball you have certainly altered the course of the cue ball. You may have discovered where the cue ball was, but now have no idea of where it is going (because you were measuring with the 8-ball instead of actually looking at the table).
Some physical entities such as light can display some characteristics of both particles and waves. Before the early 20th century, scientists believed that light was in the form of an electromagnetic wave. It wasn’t until the 20th century onwards that scientists found that light has properties of waves and particles. Scientists discovered different properties of light through experimentation and allowed them to determine that light actually has a wave-particle duality.
There are still limitations in classical cryptography, it is purely mathematical and information cannot be separated from its physical representation. In Classical physics, we use binary form to store and process the data. In the 1980s, C.Bennet, P.Benioff, R.Feynman and others observed that new and very powerful ways of information processing are possible with quantum mechanical systems. This gave birth to the concept of quantum computing.
Furthermore, my Physics class that introduced classical mechanics has prepared me for my major in science in mathematics. This class helped me because the professor focused on the general solution to a problem by using a
During the seventeenth century, the modern science of physics started to emerge and become a widespread tool used around the world. Many prominent people contributed to the build up of this fascinating field and managed to generally define it as the science of matter and energy and their interactions. However, as we know, physics is much more than that. It explains the world around us in every form imaginable. The study of physics is a fundamental science that helps the advancing knowledge of the natural world, technology and aids in the other sciences and in our economy. Without the field of physics, the world today would be a complete mystery, everything would be different because of the significance physics has on our life as individuals and as a society.