B Local gravity vs dark matter

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although I can think of instances where physicists have been wrong. It was only around 100 years ago that most physicists believed that an ether permeated the whole of space.
The bases for claims "ather permeats space" and "we know how gravity works" were and are different and the base for latter is way more scientific and empirically justified than for the former. So sorry, but you should learn how scientific method works now, not what some people thought long time ago, when scientific methods were not so strict.

Also, physics needs a healthy degree of scepticism to function properly.
Yes, but from people who know the subject in all its details (namely - other physicists), not from layman.
 
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The bases for claims "ather permeats space" and "we know how gravity works" were and are different and the base for latter is way more scientific and empirically justified than for the former. So sorry, but you should learn how scientific method works now, not what some people thought long time ago, when scientific methods were not so strict.



Yes, but from people who know the subject in all its details (namely - other physicists), not from layman.
Are methods "way more scientific and empirically justified". Where is the empirical evidence four string theory?
 
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Where is the empirical evidence four string theory?
Is anyone saying that string theory is empirically verified? No. So what's your point? Besides, this thread is about plain old classical gravity. Physicists may be wrong when it comes to untested models like string "theories", but gravity - Newtionian and Einsteinian - has been tested and observationally verified on so many levels that putting it's validity in doubt is very unreasonable, to say the least.
 
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sophiecentaur

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Yes, I can see it would be a better representation but more difficult to calculate.
But, if you want to emerge with a justification of your idea, your calculation has to be so accurate that your idea is needed to explain the discrepancy. The error, using your approximation would be vast, compared with any effect that you could attribute to dark matter.

Where is the empirical evidence four string theory?
That's not the string story at all. String theory is a possible explanation for the way things work at a very low level. Last time I read about it, it was a fairly coherent story and that makes it attractive. The claims for string theory are only based on that but the ideas of string theory are not just in isolation; they are not disproved by observation, which is different from saying they are proved.

You seem to be falling into a common trap for 'non-Scientists' and that is to underestimate the validity of Science. If you want a revolutionary model for Science then it has to include the present model in every detail. The frequent statement that "Science was Wrong" is not fair and it is not accurate about the (proper) Science that emerged, once Politics and Religion lost their influence on it.
 

Ibix

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The gravitation formula is simple but it's amazing how complicated things can become when there are hundreds of billions of gravitational bodies in a system.
If our maths was incorrect we wouldn't be able to predict the motions of planets and spaceships correctly. Yet we can do that precisely enough that we need to take into account the non-spherical shapes of the planets. Non-trivial mass distributions are well understood.

Your approach isn't vastly different from asking if physicists are sure they know how to add up. Yes, we are pretty sure we do. But the answers don't match reality. We might be doing the wrong sums (our theory of gravity may need work), or there might be things we haven't put into the sums (dark matter), but if we were not correctly processing the numbers we have we'd find errors in other things.

On a more philosophical note, the general problem with advancing science isn't coming up with new ideas. It's coming up with new ideas that aren't obviously wrong to anyone who knows anything about the topic. That's why we're hunting new types of nearly-undetectable matter or somewhat implausible tweaks to the long range behaviour of gravity - because anything more mundane would show up in other things where we don't see anything odd.
 
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Is anyone saying that string theory is empirically verified? No. So what's your point? Besides, this thread is about plain old classical gravity. Physicists may be wrong when it comes to untested models like string "theories", but gravity - Newtionian and Einsteinian - has been tested and observationally verified on so many levels that putting it's validity in doubt is very unreasonable, to say the least.
OK. More to the point what empirical evidence is there for "dark matter"?
 
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This has nothing to do with this thread, so start your own with this question. Or search for other threads about this issue, because it has been discussed here multiple times.
 
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This has nothing to do with this thread, so start your own with this question. Or search for threads for other threads about this issue, because it has been discussed here multiple times.
 

DaveC426913

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...the general problem with advancing science isn't coming up with new ideas. It's coming up with new ideas that aren't obviously wrong to anyone who knows anything about the topic.
:oldbiggrin:
 

DaveC426913

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OK. More to the point what empirical evidence is there for "dark matter"?
It's a pity you're banned, and that this is off-topic. Else I would have you look up the Bullet Cluster.
 
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The thread topic has been sufficiently discussed. Thread closed.
 

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