Physics

The Uncertainty Principle



Tweet
Lydia Epstein's image for:
"The Uncertainty Principle"
Caption: 
Location: 
Image by: 
©  

Classic physics in the 18th Century was revolutionized by Isaac Newton's laws of motion  where the mass, position, and the motion of celestial bodies were elements of a mechanistic worldview from which all outcomes could be determined. Furthermore, cause and effect defined a scientific reasoning external to, and independent of, the dynamics between object and observer. When Max Planck received the Nobel Prize in physics in 1918 for his quantum theory, the physical quantum of action initiated a new paradigm for relative rather than absolute standards of measurement.  

Quantum science identifies the uncertainty inherent in nature, as it is impossible to precisely determine both the position and momentum of an elementary particle at any given time. In principle, "relational quantum mechanics discards the notion of absolutes when defining the state of a system, absolute value of its physical quantities, or absolute event". In other words, sub-atomic particles do not occupy a fixed, measurable position, as quantum theory describes only the way systems affect each other in the course of physical interactions. With quantum science, the observer becomes part of the observed system, where "in the drama of existence, we are ourselves both actors and spectators".  

Physicist Werner Heisenberg explained that quantum science cannot offer a subtle modification to classical notions of space and time, as "quantum theory derives from the attempt to break with those customary concepts of kinematics and mechanics, and replace them with relations between concrete, experimentally derived values". In addition, the observer is no longer external and neutral, but through the act of measurement becomes himself a part of observed reality. At the subatomic level, it is revealed that "the more accurately the position of a particle is measured, the less accurately its momentum can be measured, and vice versa".  Heisenberg's uncertainty principle does not arise from any disturbance introduced by the measurement. Actually, it is a fact of nature that there is a limit on the accuracy with which we can simultaneously measure conjugate attributes.

Professeur de classe exceptionnelle Carlo Rovelli also confirmed that quantum mechanics is relative to an observer's frame of reference, and reminds us of the subjective, observer-dependent character of all physical phenomena. When referring to the values of observables independent of measurement, Rovelli suggested that "the appearance of determinate observations from pure quantum superpositions happens only relative to the interaction of the system and observer". It is proposed to interpret quantum mechanics as "a theory of relations between variables, rather than the theory of the evolution of variables in time". Rovelli's philosophy is that "actuality is relative to the functional frame of reference of each individual observer", which is a conceptual extension of the principle underlying Albert Einstein's special relativity, where absolute time does not exist. 

Einstein's theory of special relativity lies in the conclusion that the flow of time in the universe does indeed differ depending on the observer's frame of reference. Professor Stephen Hawking explained Einstein's innovative insight, where "each observer has his own measure of time. The time for someone on a star will be different from that for someone at a distance, because of the gravitational field of the star". We learn that "relativity teaches us the connection between the different descriptions of the same reality".

It can be inferred from the fundamental mathematics of quantum mechanics that there is no objectivity or observer neutrality in quantum theory. After all, we really cannot know more than the uncertainty principle allows us to know, because "there simply exists nothing more that can be known beyond its limit". That is, meaning cannot be added to the dynamic attributes of a particle beyond the uncertainty principle. It can also be said that "measurement has an essential influence on the conditions on which the very definition of the physical quantities in question rests". Heisenberg concluded that "what we observe is not nature, but nature exposed to our method of questioning." 

Whether we consider what is seen by different observers or the same observer in different frames, Physicist Hugh Everett III advised that "we are seldom interested in the absolute information of a distribution, but only in differences." When measuring indeterminate  wave-particle duality, atoms and photons can behave as either waves or particles, and the behavior observed depends upon the instruments used to measure it. A relational approach to this wave-particle duality confirms that our knowledge of a physical object is based on, at least in principle, by the experimentally detected relationships between object and observer. With respect to this measurement uncertainty, Heisenberg theorized that "the only task in physics is to describe the relation between observations." 

True, mathematical predictions seem to coincide with observations we rely on to determine the positions of stellar objects and planets. When they move relative to one another in a regular fashion, we assume that the angular momentum of planetary motions is a constant, and that the numerical value of this constant differs for each planet, relative to the distance to the Sun. However, a sphere spinning at a constant rate is stationary because it looks identical at any given instant. At the subatomic level, however, we observe an ensemble of events which happen only relative to a given observer. For example, elementary particles are electromagnetic waves of different amplitudes, phases, and frequencies, which when superimposed, result in large wave packets which gives the impression of particles moving through space and time. As stated explicitly by Everett, "it is meaningless to ask the absolute state of a subsystem - one can only ask the state relative to a given state of the remainder of the system."

 SOURCES:

 Theory of Special Relativity at http://www.spaceandmotion.com/albert-einstein-theory-of-special-relativity.htm

 Isaac Newton at http://scienceworld.wolfram.com/biography/Newton.html

 Theory of Special Relativity at http://www.thebigview.com/spacetime/relativity.html

 Wave-Particle Duality at http://physics.about.com/od/lightoptics/a/waveparticle.htm

 Relational Quantum Mechanics at http://www.illc.uva.nl/~seop/entries/qm-relational/

Hugh Everett, III, " The Many-Worlds Interpretation of Quantum Mechanics: The Theory of The Universal Wavefunction", available online at http://www.pbs.org/wgbh/nova/manyworlds/pdf/dissertation.pdf

Max Planck, "The Origin and Development of the Quantum Theory".  English translation  published by Methuen & Co. in 1925, available online at http://www-history.mcs.st-andrews.ac.uk/Extras/Planck_quantum_theory.html

Werner Heisenberg, "The Actual Content of Quantum Theoretical Kinematics and Mechanics" Translation of "Uber den anschaulichen Inhalt der quantentheoretischen Kinematik und Mechanik", Zeitschrift fur Physik, v. 43, no. 3-4, pp. 172-198, 1927. National Aeronautics and Space Administration, Washington, D.C, 20546, December 1983 

Carlo Rovelli, "The Ontological Import of Relational Quantum Mechanics", November 1, 2007, available online at http://www.cpt.univ-mrs.fr/~rovelli/ 

Stephen Hawking, "A Brief History of Time" available online at http://www.nt.ntnu.no/users/lale/e_book/stephenHawking-ABriefHistoryOfTime.pdf

H. M. Wiseman, "From Einstein’s Theorem to Bell’s Theorem: A History of Quantum Nonlocality", Centre for Quantum Dynamics, School of Science, Griffith University, Brisbane,  Queensland 4111 Australia, arxiv:quant-ph/0509061 v2 24 Sep 2005 

Louis Rougier, "Philosophy And The New Physics", An Essay on the Relativity Theory and the Theory of Quanta" Authorized Translation From the Author's Corrected Text of 'La Materialisation de I'finergie" by Morton Masius, M.A. Ph.D., published by P. Blakiston's Son & Co., copyright, 1921. 

See: arXiv:0903.3832v3 [gr-qc]       

See: arXiv:0911.1147v3 [quant-ph]  

See: arXiv:physics/0010064v1 [physics.data-an]


Tweet
More about this author: Lydia Epstein

From Around the Web




ARTICLE SOURCES AND CITATIONS
  • InfoBoxCallToAction ActionArrowhttp://www.newton.ac.uk/newton.html
  • InfoBoxCallToAction ActionArrowhttp://www-history.mcs.st-and.ac.uk/Mathematicians/Planck.html
  • InfoBoxCallToAction ActionArrowhttp://quantumscience.com/
  • InfoBoxCallToAction ActionArrowhttp://www.aip.org/history/heisenberg
  • InfoBoxCallToAction ActionArrowhttp://plato.stanford.edu/entries/qt-uncertainty
  • InfoBoxCallToAction ActionArrowhttp://www.cpt.univ-mrs.fr/~rovelli
  • InfoBoxCallToAction ActionArrowhttp://www.alberteinstein.info/
  • InfoBoxCallToAction ActionArrowhttp://www.hawking.org.uk/
  • InfoBoxCallToAction ActionArrowhttp://space.mit.edu/home/tegmark/everett
  • InfoBoxCallToAction ActionArrowhttp://physics.about.com/od/lightoptics/a/waveparticle.htm
  • InfoBoxCallToAction ActionArrowhttp://www-history.mcs.st-andrews.ac.uk/Extras/Planck_quantum_theory.html
  • InfoBoxCallToAction ActionArrowhttp://www.cpt.univ-mrs.fr/~rovelli/
  • InfoBoxCallToAction ActionArrowhttp://www.nt.ntnu.no/users/lale/e_book/stephenHawking-ABriefHistoryOfTime.pdf
  • InfoBoxCallToAction ActionArrowhttp://fr.arxiv.org/abs/0903.3832v3
  • InfoBoxCallToAction ActionArrowhttp://arxiv.org/abs/0911.1147v3
  • InfoBoxCallToAction ActionArrowhttp://arxiv.org/abs/physics/0010064v1