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Cassini Experiment Confirms General Relativity
MikeZilla writes "An experiment by Italian scientists using data from NASA's Cassini spacecraft, currently en route to Saturn, confirms Einstein's theory of general relativity with a precision that is 50 times greater than previous measurements."
Scientists know that there is always more. Once you find an answer to a question, you will open to the door to 3 more questions about something else. It is the way advances are made. You create a theory, which you test, and from those results you come up with more theories.
With this particular test, they wanted to rerun test that have been run before to see if the results from the Viking Mission hold up with the more accurate equipment available now.
Truth is only as good as the information you have. At first there was earth wind fire and water (no jokes please). Then there were atoms. Then the atoms where broke down to electrons proton and neutrons. Then those particles where broke down into quarks. Then quarks where broke down into mueons. Each time, they add to the new truth.
The fundamental philosophy of that truth doesn't change, just the details showing it is.
Fear Is the Only God
That's not really true. "Law" is something of a layman's term. In mathematics and science, there are no absolute facts, just postulates and theorems. General relativity is basically identical to Newton's theory of gravity in basic situations, but it differs when you're working with high speeds and large scales. In fact, Newtonian physics is proven wrong for many planetary-scale gravitational effects.
It's a "law" because it seems immovable to us.
> You create a theory, which you test, and from those results you come up with more theories.
You left off the first bit! You *first* observe. Theory did not come first! It came from observations, and wondering how the universe works.
e.g.
1. Observe (natural, or man-made expirements)
2. Theorize
3. Test
repeat
> Truth is only as good as the information you have.
Physical truth, yes. Meta-physical truth, I disagree. But that is a discussion for another time.
Truth doesn't change, but your perception and knowledge of it does.
Cheers
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"I want to move to theory, everything works in theory." - John Cash
What a lot of people don't seem to know is that the fact that it is still called the 'theory' of relativity means that it hasn't been accepted as gospel by scientists yet.
:)
That's not a very good description of the situation.
Contrast this with the 'law' of gravity, which has.
Actually the 'law' of gravity have been proven incorrect. It has been superceded by relativity. The common usage of 'theory' and 'law' don't quite match up with the scientific usage
According to the "law of gravity" the results from this measurement should have been zero. Relativity says the value isn't zero, and the value given by relativity is at least a 99.998% match for the measured value. The remaining 0.002% doesn't indicate a problem with relativity, it is just the limit of the accuracy of devices they used to make the measurement.
Relativity has been challenged with the most stringent scientific testing ever devised in countless ways. Actually part of the "problem" is that relativity is "too good". Absolutely everything it describes it does so with unbelievable accuracy. The irony is that you can't learn anything new when every single measurements exactly matches your predictions. It leaves them without anything to grab on to to try to explore the things that relativity doesn't explain.
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It's misleading to say that this experiment "confirms" General Relativity. What it does is fail to falsify GR. That's nothing to sneeze at. But it tests such a small part of GR that one really can't say that it "confirms" GR. These kinds of delays are part of many alternative theories as well. If you say that this experiment "confirms" GR, then it also "confirms" many theories that otherwise wildly disagree with GR.