Religious folk: Did you know that Gravity is still a theory?
There are the laws of gravity that some of you might know about from high school, but there are enough anomalies and inconsistencies to relegate what we call gravity to the status of “theory”. Earlier this week, some scientists found direct evidence of something called Dark Matter, which partially explains a major inconsistency in gravity, that being the movement of galaxies. You see, we couldn't measure enough mass in any of the visible galaxies to account for their gravitational effects. But now with the discovery of dark matter, we’re closer to understanding why galaxies behave the way they do. But dark matter still doesn’t account for everything, so we think there might be something called dark energy as well. But we have no proof. Hence, gravity is still a theory.
Remember that the next time you say something is “Just a theory”
Asked By: l00kiehereu - 8/25/2006
You wrote: "There are the laws of gravity that some of you might know about from high school, but there are enough anomalies and inconsistencies to relegate what we call gravity to the status of 'theory'."
You obviously do not understand. In science, a 'Law' is expressed where scientists notice a mathematically consistent relationships of parameters within a dynamic system wherein, given knowledge of one or more parameters and known standard equations, future states of the system can be calculated or, alternatively, past states of the system can be revealed. Such is Newton's 'Universal Law of Gravitation'... it allows us to calculate how objects will behave under the influence of gravity, but it tells us nothing at all about gravity itself... i.e., what gravity is or how it works.
Your statement about "...there are enough anomalies and inconsistencies to relegate what we call gravity to the status of 'theory'" is just flat wrong... more on that below.
You wrote: "Earlier this week, some scientists found direct evidence of something called Dark Matter, which partially explains a major inconsistency in gravity, that being the movement of galaxies."
That has nothing to do with an "inconsistency in gravity"... it has to do only with a unexpected (or better, unexplained) observations in the movements of stars and galaxies.
I get really sick of all these scientifically ignorant nut-jobs screeching "... it's only a 'theory'... not a fact." In science, 'theories' occupy a higher tier of importance than mere 'facts'... theories EXPLAIN facts.
Newton's 'Theory of Gravitation' postulated that gravity's effects were caused by an unseen gravitational 'force'. This theory was meant to EXPLAIN the CAUSE behind the OBSERVED FACTS of the effects of gravity that are described in the equations set forth in the Law of Gravitation. This 'theory' (explanatory framework for the facts) is now defunct, since we now know (or, THINK we know) that gravity is explained by Einstein's 'Theory of General Relativity', and that the FACTS of gravity are explained as being a consequence of the curvature of space-time, rather than an invisible force. Same facts... different theory.
Einstein's theory also revealed to us that the 'Law of Gravitation' was wrong, as well... at relativistic velocities, and in the presence of very large masses, Newton's equations do not work. Also, at the quantum level, neither Newton's nor Einstein's equations work. HOWEVER, we still use Newton's equations, and refer to Newton's 'Law of Gravitation' in a LOCAL environment... 'local' meaning non-relativistic. Why? Because, in a 'local' environment, the answers to the calculations come out the same (within a certain number of decimal places), whether Einstein's or Newton's equations are used... and Newton's math is EASIER. So, we still refer to Newton's Law of Gravitation, and still use it for building skyscrapers and bridges, and for sending satellites into orbit, or to visit the Moon or Mars, or to calculate the ballistic curve of an artillery projectile for reasons of PRACTICALITY.
Now... the 'Theory of Evolution. Evolution is not a matter of 'belief. I keep reading in here that "... evolution is just a theory... not a fact." That, as it turns out, is true... although the word 'just' is inappropriate, and misleading... and it indicates that people just don't understand what a scientific theory is; they seem to think that it is just an idea. Nothing could be further from the truth.
Again... in science, a theory occupies a higher stratum of importance than a mere 'fact'. Theories EXPLAIN facts. The theory of evolution provides an explanatory framework for the OBSERVED FACT that the genetic makeup of populations of organisms changes, over time (in some cases, over distance)... and that over an extended period of time (hundreds, thousands, tens of thousands of generations), the accumulation of those changes can result in speciation. It explains the OBSERVED FACT of transitional species found in the fossil record.
Theories live or die on the basis of their explanatory power and falsifiability. Theories, as an explanatory framework, allow one to make predictions which can be subsequently validated by way of experiments or future observations. That means that in order to be valid, a theory must be falsifiable... and all that it takes for a theory to be falsified is ONE INSTANCE where an experiment or future observation achieves a result that is CONTRARY to what the theory has predicted.
Evolution, as it turns out, has NEVER been falsified... in nearly 150 years. Further, all findings and observations to date... in molecular biology... in genetics... in paleontology... have SOLIDIFIED the explanatory power of evolution... NEVER detracted from it.
For those that say that evolution does not account for new species... h*******t. Examples abound, both in the 'world' and in the laboratory. One of the most interesting examples, and the most enlightening, has to do with a kind of bird (plovers, if my memory is correct) that occupies adjacent habitats all the way from Siberia to Britain. Because of environmental differences in these adjacent habitats, natural selection has produced genetic differences between the populations in these adjacent habitats. However, birds in adjacent habitats can still mate with each other... the genetic differences are small. However, the birds from the Eastern-most reaches of Siberia CAN NOT mate with those from Britain. Over the reach of MANY habitats, the accumulation of genetic differences essentially differentiates them as a species.
Answered By: DuckPhup - 8/25/2006