Is General Relativity Incomplete Without Dark Matter and Dark Energy?

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mustang19
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Dark matter and dark energy are fudge factors to solve problems in general relativity such as unexplained mass and drag. Is this correct or am I missing something?
 
on Phys.org
The evolution of physics is that we develop theories that explain the things we can measure and then we continue to explore new areas and continue to apply the theory. When a given theory doesn't seem to work we check if our understanding is correct or that there is some hidden cause for the discrepancy before we decide to sack the theory and look for a new one.

In the case,of General Relativity every measureable experiment has confirmed that is still a valid and useful theory to explore the cosmos. It is because of its predictive accuracy that we have discovered the effects that we now say are due to dark matter and dark energy. It's natural then that scientists seek something to explain the discrepancies in measurements rather than scrap General Relativity.

If someone were to come along with a new theory that explained all of General Relativity's results, together with dark energy and dark matter anomalies then it could be a contender but we've not seen such a theory yet.
 
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In the case,of General Relativity every measureable experiment has confirmed that is still a valid and useful theory to explore the cosmos.

Besides the cases I mentioned
 
mustang19 said:
Is this correct or am I missing something?

You're missing something. What you're missing is that there are no other models currently known that account for all the data and do not have dark matter and dark energy in them. There are speculative models that do not include dark matter and dark energy, but they only account for some of the data, not all of it.

mustang19 said:
Besides the cases I mentioned

The cases you mention don't disconfirm GR, since we have a valid GR model that accounts for that data. So your claim here is false.
 
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mustang19 said:
Dark matter and dark energy are fudge factors to solve problems in general relativity such as unexplained mass and drag. Is this correct or am I missing something?
How would you characterize the discovery of the neutrino, or the planet Neptune? Both were predicted because it was more plausible that they existed and explained the discrepancy between theory and observation than that the theory was wrong.
 
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mustang19 said:
Dark matter and dark energy are fudge factors to solve problems in general relativity such as unexplained mass and drag. Is this correct or am I missing something?
Mass density of the universe is a parameter of our GR models. The "cosmological constant" is a parameter of the same models. Neither is known a priori, so both need to be established by experiment. That called is doing science, not fudging.
 
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Vanadium 50 said:
I'm sorry - where in the Einstein Field Equations does it say "all matter must be luminous"? I'm having a hard time finding it.
Exactly what I told the judge after running over the dog:cry:
 
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