Quote: (03-16-2013 01:02 PM)Samseau Wrote:
Gravity wasn't even understood as a concept until Newton came around. Galileo was the first to accurately make observations on it. After general relativity the concept of gravity changed again.
Yes, because Newton's theory could not explain the orbit of Mercury. Lesson to be learned: Newton's theory fails when the gravitational field is too strong. However, when NASA launches a space probe, they use Newton's theory, and then make some corrections using GR when necessary (e.g., to sync the clocks of GPS satellites).
Was Newton wrong and Einstein right? I would say they were both "right", but their theories had different domains of applicability. GR is more broad, more general, but it's also overkill if all you want is to compute the orbit of a satellite.
Quote: (03-16-2013 01:02 PM)Samseau Wrote:
The fact that gravity was slowly discovered and whose understanding has changed multiple times is all the proof you need to know that someday the concept of gravity will be replaced.
I disagree. You don't update a theory because it was updated in the past. You update it because it fails to explain experimental phenomena. And the concept of gravity won't be "replaced", it will be refined. Let's wait till the LIGO thing detects some gravitational waves...
Quote: (03-16-2013 01:02 PM)Samseau Wrote:
But that's why science can't prove anything - we don't have total knowledge, and the quest for answers will always continue.
Science can prove things... via experimentation. If you come up with an hypothesis, and experiment fails to validate such hypothesis, then your hypothesis is wrong. If the hypothesis is validated, you cannot conclude it's correct. Science can prove that hypotheses are incorrect, but it can't prove they are correct.
In other words, natural scientists (e.g., physicists, chemists, biologists) don't spend their days trying to prove things right, they try to prove things wrong.