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Essay:Rebuttal to Counterexamples to Relativity (view source)
Revision as of 03:48, October 14, 2014
, 03:48, October 14, 2014Number 16.
#:For a particle with mass, this means that momentum of zero gives a speed of zero, and, as the momentum approaches infinity, the speed approaches c.
#:For a particle with mass, this means that momentum of zero gives a speed of zero, and, as the momentum approaches infinity, the speed approaches c.
#:For a massless particle, the speed is always c.
#:For a massless particle, the speed is always c.
#Unrebutted.
#''observations don't match predictions'' and cosmic causality.
#:The fact that "observations don't match predictions" has shown up many times in the history of science. That is, the accepted wisdom of the day was found to be false, leading to improved theories:
#:*There were once assumed, by Aristotle and many others, to be four elements: earth, air, fire, and water. Subsequent experimental investigation, by numerous people, replaced that theory.
#:*The Aristotelian notion of gravity, that objects fall at a speed proportional to their mass, was found to be contrary to experimental evidence, and was replaced by Galilean/Newtonian mechanics.
#:*The geocentrism of Ptolemy lasted a long time until it was found to be contrary to experimental evidence, and was replaced by the Heliocentric theory of Copernicus, Galileo, and Newton.
#:*The "phlogiston theory" of combustion was accepted until it proved to be contrary to experimental evidence, and was replaced by the modern oxidation theory by Antoine Lavoisier.
#:*The "caloric theory" supposed that heat was a material substance called "caloric", and that that substance was conserved. It took a long time for Joule and others to develop the modern "kinetic theory" as a replacement.
#:
#:The current "counterexample" is about the "horizon problem", a problem of cosmology which has been known for a few decades. Under the kind of expansion of the universe that non-quantum-mechanics would require, there are places in the universe that are not causally connected and yet have nearly the same temperature. The classical expansion of the universe would have magnified early nonuniformities by about 50 orders of magnitude, an impossible situation. The currently accepted theory dealing with this problem is "inflation". Not all scientists accept this, but most do; other explanations are more exotic than most scientists are willing to accept.
#:
#:An interesting thing about inflation is that it was formulated to solve a different problem—the dominance of matter over antimatter. It was found to address the flatness problem as well. When a theory explains phenomena other than what it was intended for, that of course lends it additional credence.
#:
#:Whether cosmic inflation is implausible is not for us to say. The existence of subatomic particles was once considered implausible.
#:
#:The cited National Geographic article was in fact not about the problem of temperature uniformity, but about various hypotheses, much less widely accepted than inflation, about alternate universes, and whether black hole singularities might connect them. The issue is not about the existence of black holes, but about the connectedness of their singularities. This is really fascinating stuff. The book ''The Hidden Reality'', by Brian Greene, is a fascinating account of these issues. We highly recommend it.
#''The logical problem of a force which is applied at a right angle to the velocity of a relativistic mass - does this act on the rest mass or the relativistic mass?''
#''The logical problem of a force which is applied at a right angle to the velocity of a relativistic mass - does this act on the rest mass or the relativistic mass?''
#:The simple answer is, unequivocally, that it acts on the 'relativistic' mass. The question seems to relate to a simple misunderstanding of Special Relativity. Einstein's theories lead to the conclusion that observers in different inertial frames of reference (i.e. observers with differing, but constant velocities relative to the thing being observed) will observe different inertial masses in the body being observed. However, there is no variance in the body's mass with regard to the direction of the force. Thus to a given observer, a force in any direction will operate on the same mass. However, to a different observer, this mass may be different, although still the constant with regard to the direction of the force.
#:The simple answer is, unequivocally, that it acts on the 'relativistic' mass. The question seems to relate to a simple misunderstanding of Special Relativity. Einstein's theories lead to the conclusion that observers in different inertial frames of reference (i.e. observers with differing, but constant velocities relative to the thing being observed) will observe different inertial masses in the body being observed. However, there is no variance in the body's mass with regard to the direction of the force. Thus to a given observer, a force in any direction will operate on the same mass. However, to a different observer, this mass may be different, although still the constant with regard to the direction of the force.