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Comment by ajkjk | Hacker News Reader

Are you a physicist? What possibly makes you think you have enough background to disregard the (tremendous) evidence for it?

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I admit that I haven't been reading about dark matter lately. Last I checked, it had not been verified via experimental evidence. Is that still the case?

There is a difference between observations and _experimental_ evidence, which I think the GP was referring to.

It is heavily verified by experimental evidence, and has been since it was first proposed. That's why people have spent so much time studying it. It's not like it was just a random hair-brained idea someone had.

The only thing we haven't done is figured out what it is in terms of other concepts we know, such as elementary particles.

Sure, the anomolous observations are verified, but there is no experiment that has been conducted to directly detect it as far as I know. What you said about what we don't know is precisely my point. Given that this article mentions the discrepancy between models and observations, I'd say we know hardly much at all about it--whatever it may be given that we can't directly detect it and we can't even make a good model to predict its behavior

Sure, keep down voting me, but read this https://en.wikipedia.org/wiki/Dark_matter#Detection_of_dark_...

Healthy skepticism is a good thing for science. Until DM is proven, it is worth exploring other avenues--may the best experiment win. If you don't understand this, you are a zealot rather than a scientist.

Everyone here agrees that healthy skepticism is good for science. The GP's post was not healthy skepticism:

> Honestly, I'm a little tired of the whole dark matter thing. There's no evidence for it, and physicists keep coming up with more and more complex models to fit the data when they don't actually understand what's going on there.

Reads as:

"I know nothing, but I assume that there's no evidence for this because I haven't done any research, and I assume that physicists are foolishly sticking to the theory because they're desperate".

This couldn't be further from the truth, and it could be dispelled with 5 minutes of googling.

You're being downvoted for the same dismissive cluelessness:

> Last I checked, it had not been verified via experimental evidence. Is that still the case?

In reality, there has been mountains of experimental evidence ever since the theory was first proposed, which is why it has been taken seriously for decades. That's why the "Observational evidence" section on Wikipedia has 11 sections in it, reflecting thousands of papers. We still don't know what it is at an _atomic_ level but we know where it is, what it weighs, how it moves, and what it interacts with.

To be fair, there is a lot of evidence for the phenomena described as "dark matter", but as yet zero detection of actual matter that fits it's properties.

Perhaps that is the complaint here - and asking for academic background is an argument from authority...

So the name of dark matter might be misleading, but there is some mass/pressure/something that's causing gravitational lensing but itself doesn't interact with light.

> as yet zero detection of actual matter that fits it's properties.

Except for all the ways we have to detect actual matter (i.e. gravitation) that fits its properties.

You are assuming this thing exists because it has properties to fit your observations, and then using that as evidence that said thing exists. I'm not saying DM doesn't exist..it probably does, but your logic is flawed

I am just another armchair physicist but saying there is no detection of dark matter sounds a bit like circular reasoning. You detect matter like your phone in your hand through electromagnetic interaction. We have detected that there is something in space that completely disregards electromagnetic force, but exerts gravitational force. Hence the idea that we have not detected it is simultaneously false in 2 ways:

- it cannot be detected the way you detect your phone in your hand or see light so your definition of detection seems to escape the basic premise of dark matter: its ability to avoid electromagnetic force, and also,

- we have detected it through gravitational anomalies

But to be fair, you can detect the phone in your hands many many many ways.

With the DM effect, we ONLY see gravitational anomalies as you said. Though DM may very well be the reason, it does not automatically mean it MUST be some matter we cannot see

and asking for academic background is an argument from authority...

No it isn't. It isn't even an argument of any sort. I think most reasonable people would interpret that as an attempt to gather evidence to support applying a heuristic filter to the question of "is it worth my time to continue engaging with this person or not?"

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