5 ms·

> Our understanding of gravity might be completely wrong. Why do you think this hypothesis is simpler than the existence of matter we haven’t detected yet? >

> Our understanding of gravity might be completely wrong. Why do you think this hypothesis is simpler than the existence of matter we haven’t detected yet? > If 85% of the gravity is unexplainable that seems like a pretty safe bet. It’s not unexplainable. There are plenty of candidates for dark matter, such as WIMPs, MACHOs, and axions. See here for a discussion: http://www.preposterousuniverse.com/blog/2012/05/09/dark-matter-vs-modified-gravity-a-trialogue/ http://www.preposterousuniverse.com/blog/2012/05/09/dark-mat...

roenxi 8y ago
> Why do you think this hypothesis is simpler than the existence of matter we haven’t detected yet? Scientifically speaking, if you can't detect 85% of something that you think is there, then you have to admit to the possibility that it does not exist. For example, the original article has this poorly-phrased sentence - "Not finding dark matter in an experiment is not evidence that dark matter doesn’t exist". Clearly the writer does not literally mean what they wrote, because not finding something in an experiment _is_ evidence it does not exist. It is pretty obvious something is going on, we have lots of highly suggestive data. As you point out there are lots of extremely plausible explanations. But until we have some direct evidence, then we are in a situation where there is no direct evidence that it exists. Therefore, it might not. That remains a very simple explanation. As I was alluding to when comparing this situation to the aether, and as other commenters have pointed out, working on the question of what light was turned out to break time. Same thing might happen with gravity.
- antidesitter 8y ago
  > you have to admit to the possibility that it does not exist > we are in a situation where there is no direct evidence that it exists. Therefore, it might not. You are moving the goalposts. No one denies it is possible that none of these dark matter candidates exist. > not finding something in an experiment _is_ evidence it does not exist Which "experiment" are you referring to? This is only true if you would expect the experiment to detect such a thing.

roenxi 8y ago

> Why do you think this hypothesis is simpler than the existence of matter we haven’t detected yet? Scientifically speaking, if you can't detect 85% of something that you think is there, then you have to admit to the possibility that it does not exist. For example, the original article has this poorly-phrased sentence - "Not finding dark matter in an experiment is not evidence that dark matter doesn’t exist". Clearly the writer does not literally mean what they wrote, because not finding something in an experiment _is_ evidence it does not exist. It is pretty obvious something is going on, we have lots of highly suggestive data. As you point out there are lots of extremely plausible explanations. But until we have some direct evidence, then we are in a situation where there is no direct evidence that it exists. Therefore, it might not. That remains a very simple explanation. As I was alluding to when comparing this situation to the aether, and as other commenters have pointed out, working on the question of what light was turned out to break time. Same thing might happen with gravity.

antidesitter 8y ago
> you have to admit to the possibility that it does not exist > we are in a situation where there is no direct evidence that it exists. Therefore, it might not. You are moving the goalposts. No one denies it is possible that none of these dark matter candidates exist. > not finding something in an experiment _is_ evidence it does not exist Which "experiment" are you referring to? This is only true if you would expect the experiment to detect such a thing.