Observational Constraints On Theories
Choosing among these rival scenarios is done by 'weighing' the universe, for example, measuring the relative contributions of matter, radiation, dark matter and dark energy to the critical density. More concretely, competing scenarios are evaluated against data on galaxy clustering and distant supernovae, and on the anisotropies in the Cosmic Microwave Background.
Read more about this topic: Ultimate Fate Of The Universe
Famous quotes containing the words constraints and/or theories:
“The analogy between the mind and a computer fails for many reasons. The brain is constructed by principles that assure diversity and degeneracy. Unlike a computer, it has no replicative memory. It is historical and value driven. It forms categories by internal criteria and by constraints acting at many scales, not by means of a syntactically constructed program. The world with which the brain interacts is not unequivocally made up of classical categories.”
—Gerald M. Edelman (b. 1928)
“The real trouble about women is that they must always go on trying to adapt themselves to men’s theories of women, as they always have done. When a woman is thoroughly herself, she is being what her type of man wants her to be. When a woman is hysterical it’s because she doesn’t quite know what to be, which pattern to follow, which man’s picture of woman to live up to.”
—D.H. (David Herbert)