The current cosmological paradigm, the cold dark matter model with a cosmological constant, requires that the mass-energy of the Universe be dominated by invisible components: dark matter and dark energy. An alternative to these dark components is that the law of gravity be modified on the relevant scales. A test of these ideas is provided by the baryonic Tully-Fisher relation (BTFR), an empirical relation between the observed mass of a galaxy and its rotation velocity. Here, I report a test using gas rich galaxies for which both axes of the BTFR can be measured independently of the theories being tested and without the systematic uncertainty in stellar mass that affects the same test with star dominated spirals. The data fall precisely where predicted a priori by the modified Newtonian dynamics.
Stacy McGaughRelated topics
alternative ax cold constant current dark datum dynamics energy fall galaxy gas gravity invisible law mass matter model modified newtonian paradigm relation report rich rotation star test uncertainty universe using velocity scales mass-energyRelated quotes
As conceived in this book, economics is the science of rational choice in a world─our world─in which resources are limited in relation to human wants. The task of economics, so defined, is to explore the implications of assuming that man is a rational maximizer of his ends in life, his satisfactions─what we shall call his "self-interest.” Rational maximization should not be confused with conscious calculation. Economics is not a thoery about consciousness. Behavior is rational when it conforms to the model of rational choice, whatever the state of mind of the chooser.(...) Nor is perfect rationality assumed; rational-choice thoery allows us to assume that rationality is "bounded” because of human cognitive limitations, although another way to think of those limitations is as costs of absorbing and using information.
Richard Posner
No former age was ever in such a favorable position with regard to the sources of our knowledge of human nature. Psychology, ethnology, anthropology, and history have amassed an astonishingly rich and constantly increasing body of facts. Our technical instruments for observation and experimentation have been immensely improved, and our analyses have become sharper and more penetrating. We appear, nevertheless, not yet to have found a method for the mastery and organization of this material.... Unless we succeed in finding a clue of Ariadne to lead us out of this labyrinth, we can have no real insight into the general character of human culture; we shall remain lost in a mass of disconnected and disintegrated data which seem to lack all conceptual unity.
Ernst Cassirer
Other qualities of bodies are connected with simple energy of motion and energy of position. Such is heat, which we find by experiment can be turned into work. Finding it convertible with energy, we call it a form of energy. ...But as to heat, it is further established by experiment that in this case the energy of motion does really persist as such. Thus a gas consists of molecules flying about with velocity, rotating and vibrating, and so having energy motion. All this energy of motion is what we call heat, and thus heat is a repetition of a known meaning of energy. Again, heat exists between a radiating body and the thing it warms; now the intermediate space is filled by the luminiferous ether, which, being elastic, has in its ultimate parts both energy of motion energy of position. In these forms the heat exists in the space in question.
William Kingdon Clifford
At present, I am particularly excited by 'bad taste'. I have the deep feeling that there exists in the very essence of bad taste a power capable of creating those things situated far beyond what is traditionally termed 'The Work of Art'. I wish to play with human feeling, with its 'morbidity' in a cold and ferocious manner. Only very recently I have become a sort of gravedigger of art (oddly enough, I am using the very terms of my enemies). Some of my latest works have been coffins and tombs. During the same time I succeeded in painting with fire, using particularly powerful and searing gas flames, some of them measuring three to four meters high. I use these to bathe the surface of the painting in such a way that it registered the spontaneous trace of fire.
Yves Klein
It was early 1932, when Einstein and I both were at the California Institute of Technology in Pasedena, and we just decided to look for a simple relativistic model that agreed reasonably well with the known observational data, namely, the Hubble recession rate and the mean density of matter in the universe. So we took the space curvature to be zero and also the cosmological constant and the pressure term to be zero, and then it follows straightforwardly that the density is proportional to the square of the Hubble constant. It gives a value for the density that is high, but not impossibly high. That's about all there was to it. It was not an important paper, although Einstein apparently thought that it was. He was pleased to have a simple model with no cosmological constant. That's it.
Willem de Sitter
