24 JAN 2015 by ideonexus

 The Mistake of Not Taking Theories Seriously Enough

This is often the way it is in physics. Our mistake is not that we take our theories too seriously, but that we do not take them seriously enough. It is always hard to realize that these numbers and equations we play with at our desks have something to do with the real world. Even worse, there often seems to be a general agreement that certain phenomena are just not fit subjects for respectable theoretical and experimental effort. . . . The most important thing accomplished by the discovery o...
Folksonomies: hypotheses theories
Folksonomies: hypotheses theories
  1  notes
 
13 DEC 2011 by ideonexus

 The Precarious Laws of Nature

By examining the model universes we generate when the theories of physics are altered in certain ways, one can study the effect of changes to physical law in a methodical manner. It turns out that it is not only the strengths of the strong nuclear force and the electromagnetic force that are made to order for our existence. Most of the fundamental constants in our theories appear fine tuned in the sense that if they were altered by only modest amounts, the universe would be qualitatively diff...
  2  notes

If the laws of nature were different by a very small amount, the Universe would not work in such a way as to produce life.

12 DEC 2011 by ideonexus

 The Four Forces of Nature

1. Gravity. This is the weakest of the four, but it is a long-range force and acts on everything in the universe as an attraction. This means that for large bodies the gravitational forces all add up and can dominate over all other forces. 2. Electromagnetism. This is also long-range and is much stronger than gravity, but it acts only on particles with an electric charge. being repulsive between charges of the same sign and attractive between charges of the opposite sign. This means the ele...
Folksonomies: physics laws laws of nature
Folksonomies: physics laws laws of nature
  1  notes

Gravity, Electromagnetism, the Strong and Weak Nuclear Forces with brief descriptions.