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Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @10:47AM (#14382602)
Dark matter appears, to a layman with some historical knowledge, as nothing more than modern day epicycles. When we can't explain something with the models we have, and have to invent magic terms to balance the equations, that indicates that we really don't know what the fuck is going on.
Re:A Physicist Who Denies Dark Matter by hwillis on Saturday May 20, 2017 @11:04AM (#14382690)
You have a misunderstanding of the problems and evidence of dark matter: https://www.reddit.com/r/space/comments/6488wb/i_dont_want_t...
Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @11:07AM (#14382706)
I'm not seeing anything there that isn't a handwavey explanation for "reality doesn't match the models, so DARK MATTER!"
Re:A Physicist Who Denies Dark Matter by hwillis on Saturday May 20, 2017 @11:40AM (#14382873)
>One of the recent most convincing things was the bullet cluster as described here.[1] We saw two galaxies collide where the "observed" matter actually underwent a collision but the gravitational lensing kept moving un-impeded which matches the belief that the majority of mass in a galaxy is collisionless dark matter that felt no colliding interaction and passed right on through bringing the bulk of the gravitational lensing with it.

How can you possibly even begin to explain that without dark matter?

[1] http://www.preposterousuniverse.com/blog/2006/08/21/dark-mat...

Re:A Physicist Who Denies Dark Matter by lightlyused on Monday May 22, 2017 @12:08PM (#14394693)
Parallel universes?
Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @11:44AM (#14382894)
We don't understand how matter acrually works on a large scale. Inventing imaginary terms that we can't observe to satisfy the equations in the models to match the observed reality seems a poor practice.
Re:A Physicist Who Denies Dark Matter by hwillis on Saturday May 20, 2017 @11:57AM (#14382960)
We understand that when two galaxies hit each other, the visible mass gets all tangled up and suns and nebula smash into each other. Meanwhile the invisible mass continues onwards, oblivious to everything else. We CAN observe it and we have.

Seriously this is basic object permanence. We can see hidden things moving around by themselves. Dark matter is still there even when there's normal matter on top of it.

Re:A Physicist Who Denies Dark Matter by Avshalom on Saturday May 20, 2017 @12:02PM (#14382996)
No.

When the model is wrong, you build a new model. A bunch of weakly interacting particles is the new model.

Re:A Physicist Who Denies Dark Matter by gaius on Saturday May 20, 2017 @12:35PM (#14383141)
Right it's like when people say, I don't believe in Creation, that stuff is just nonsense. And you say, so what's your alternative theory then? And they reply, well there was a "big bang" and everything just sort of appeared, for no reason. Really, that's the alternative explanation?
Re:A Physicist Who Denies Dark Matter by hwillis on Saturday May 20, 2017 @12:45PM (#14383185)
Well yes, if you ignore all the evidence of something then you can confidently say there is no evidence.

Christian genesis: There was a garden of Eden, and a god.

Evidence: No garden of Eden, no evidence of angels or god, no reason those things would suddenly stop being apparent. Direct contradictory evidence that YHWH[1] was a minor god in the original jewish pantheon rather than an actual creator god.

Big Bang: The universe started for an unknown reason and rapidly expanded outward.

Evidence: The universe is visibly expanding outwards and formed in a way consistent with an explosion.

Did you think that the big bang theory was just something someone thought of, and then they looked for evidence? Evidence came first, then the big bang was proposed.

[1]: https://en.wikipedia.org/wiki/Yahweh

Re:A Physicist Who Denies Dark Matter by shakna on Saturday May 20, 2017 @03:08PM (#14383814)
> Christian genesis: There was a garden of Eden, and a god.

That's a really bad example to go to.

The tale of Eden follows a poem, and if you take both literally, then you end up with contradictions.

For why? Genre.

Neither were intended to be literal. They were designed to convey meaning.

> YHWH[1] was a minor god in the original jewish pantheon rather than an actual creator god.

Origins are highly disputed, but El seems to be the most likely title, who is the head of the Caananite pantheon, and influential enough to be remembered in Babylon. Not a minor deity.

I understand you were responding to a statement which sort of ignores the basic premises of science, but that doesn't mean your narrative should ignore a scholarly approach to documents whose origins predate writing.

Re:A Physicist Who Denies Dark Matter by hwillis on Saturday May 20, 2017 @03:35PM (#14383957)
>Neither were intended to be literal. They were designed to convey meaning.

Even Genesis has direct geographical references to it. It has directions. Calling it a metaphor is moving the goalposts. Ad reductio Abrahamic religion is simply that god made whatever we can't understand.

It's not like I'm saying the world wasn't made in seven days. I'm saying that god said we were kicked out of where we came from and would never be allowed back, and that place doesn't exist. I'm saying god says he talks to us and appears to us, and those things don't happen. The basic, central tenants of the bible aren't real. These are important things, not minutia.

>Origins are highly disputed, but El seems to be the most likely title, who is the head of the Caananite pantheon, and influential enough to be remembered in Babylon. Not a minor deity.

That's not true. The introduction of Yahweh to the Semetic religion was very visibly followed by a shift in personal names referencing El (eg Michael) to names referencing Yahweh. Yahweh was an individual, entirely separate god that aggressively replaced El, and El was relegated to an increasingly minor role. The thing called YHWH in 1200 BC is a 4th tier divine warrior, and the thing called YHWH now is a sole god.

Bare minimum, the Semetic religion was demonstrably polytheistic before it was monotheistic, and that alone massively undermines the bible.

Re:A Physicist Who Denies Dark Matter by shakna on Saturday May 20, 2017 @04:26PM (#14384182)
> Even Genesis has direct geographical references to it. It has directions.

Treating Genesis as a single book is insane. Its a collection of oral traditions. Multiple authours, genres, and hundreds of years separate each tale.

> geographical references to it. It has directions. Calling it a metaphor is moving the goalposts. Ad reductio Abrahamic religion is simply that god made whatever we can't understand.

Eden isn't a metaphor, its an allegory, using as its basis a common Mesopotamian myth, as was common at the time. Its origin lies in the story of Lilitu.

The directions to the Euphrates are in Babylonian and Egyptian myths too. It was an area considered symbolic of the spiritual world. You get similar directions to forests that never existed in Japanese myths.

And as a people, the Caananites, and their descendants, were incredibly symbolic. See Kabbalah's number system, and references to it throughout the Bible.

> The introduction of Yahweh to the Semetic religion was very visibly followed by a shift in personal names referencing El (eg Michael) to names referencing Yahweh.

Firstly, "Yahweh" was a best guess about an unspoken name that wasn't allowed to be written in complete form. We are fairly certain that guess was wrong, and the actual name was "Elohim". They're the same name, and yes, the same spelling. (We transliterate to English using sounds in this case).

El wasn't replaced, nor were his attributes. The Caananites set out to seize their promised land, backed by their warrior god.

> the thing called YHWH is a sole god.

Not to begin with, in Biblical record. Or commands such as:

> I am a jealous god, you will have no gods before me

Wouldn't make sense. Nor would the Caananites hospitality to those of the Ba'al religions.

The Biblical record shows this, and it doesn't undermine the record. The Psalms frequently reference belief in other gods.

The first reference to monotheism comes in the Davidic era, after Israel has been established, but it isn't entirely fixed, and instead is something that slowly took hold over a great deal of time.

Different scholars and theologians have different theories on the why of that.

> that alone massively undermines the bible.

I wasn't arguing for or against it. I was simply explaining a couple of documents in a large collection have different intended meaning than that which you gave it.

We don't simply lift out parts of Herodotus and think that we should take his mentions of Achilles literally.

The Bible is a collection of documents. The meaning ascribed to them doesn't exempt them from treating them as ancient documents.

I'm sure they seem insane to you, but no moreso than our ancient Greek records, or the Roman ones either.

Re:A Physicist Who Denies Dark Matter by hwillis on Saturday May 20, 2017 @05:09PM (#14384365)
There is no evidence that locations such as that were meant as allegories. They grew from real sacred places, as appear in other religions. As cultures grew the religions simply grew with them and was re-interpreted. The metaphor is not the original meaning.

>Firstly, "Yahweh" was a best guess about an unspoken name that wasn't allowed to be written in complete form. We are fairly certain that guess was wrong, and the actual name was "Elohim". They're the same name, and yes, the same spelling. (We transliterate to English using sounds in this case).

I have no idea where you're getting this from. They are quite different. Aleph lamed he yud mem vs. yud he waw he. There was heavy redaction in the 5th century BC in favor of "Elohim" but YHWH definitely existed first. Elohim in ugaritic originally meant "children of god" ie the pantheon under El, which Yahweh was a part of. Later, with the revisionist history, Elohim became "God of gods". What's more, YHWH is forbidden to speak aloud whereas elohim is not.

There was an outright movement as YHWH became more important and El became less important. It wasn't just a name change. They literally switched, and even after Yahweh became the most important god he still didn't fully absorb El's traits until later.

>Wouldn't make sense. Nor would the Caananites hospitality to those of the Ba'al religions. The Biblical record shows this, and it doesn't undermine the record. The Psalms frequently reference belief in other gods. The first reference to monotheism comes in the Davidic era, after Israel has been established, but it isn't entirely fixed, and instead is something that slowly took hold over a great deal of time. Different scholars and theologians have different theories on the why of that.

I dropped a "now", that was meant to say "the thing now called YHWH is a sole god". But even in Kings, Baal and others are no more than false idols eg Ahab, Jezebel and Elijah.

>The Bible is a collection of documents. The meaning ascribed to them doesn't exempt them from treating them as ancient documents.

I did not mean to imply that. Certainly it is not nothing. However it is not realistic evidence for a god any more than the Greek pantheon. We know that there are no gods on top of Olympus. The hyperbolic and contradicted aspects of the bible are likewise not real.

Re:A Physicist Who Denies Dark Matter by quickben on Saturday May 20, 2017 @07:51PM (#14385013)
>>Christian genesis: There was a garden of Eden, and a god.

We'll, technically, Genesis starts with a universe filled with water, and science stars with a universe filled with hydrogen (that can be detected) and potentially other stuff that can't.

On the outside, both stories are the same and have gaping holes in their logic.

Re:A Physicist Who Denies Dark Matter by alayne on Saturday May 20, 2017 @06:32PM (#14384720)
Creationism is nonsense and has no place in a scientific discussion because it's not a falsifiable scientific theory. Thanks for derailing this discussion.
Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @12:46PM (#14383187)
When you get down to the bedrock, there's very little difference between theistic and atheistic explanations for creation.
Re:A Physicist Who Denies Dark Matter by gaius on Saturday May 20, 2017 @01:44PM (#14383461)
Absolutely. "Big bang" or "let there be light", what's the difference?
Re:A Physicist Who Denies Dark Matter by krapp on Saturday May 20, 2017 @06:37PM (#14384732)
>"Big bang" or "let there be light", what's the difference?

There is evidence supporting the existence of the Big Bang. There is no evidence supporting the existence of the Judeo-Christian God.

Re:A Physicist Who Denies Dark Matter by DanBC on Saturday May 20, 2017 @06:38PM (#14384739)
People are prepared to drop big bang if the evidence changes.
[dead]
Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @01:46PM (#14383468)
A.) God waved his finger, and the universe sprang into existence.

B.) something happened, and the universe sprang into existence.

[dead]
Re:A Physicist Who Denies Dark Matter by manquer on Sunday May 21, 2017 @01:52AM (#14385889)
disingenuous.. we have zero understanding of "something happened" a lot of about everything later, you are conflating the two.

If you have better logical or scientific explanation than God about the actual creation I am very interested

Re:A Physicist Who Denies Dark Matter by laretluval on Saturday May 20, 2017 @11:13AM (#14382731)
It's still a nontrivial observation that the equations can be corrected to account for reality most simply by adding a term for unseen matter (rather than some factor or some other mathematical operation).

Maybe the term doesn't have a straightforward physical explanation but there's a long history of introducing math without any corresponding mechanistic explanation---this is what gravity itself was until general relativity, nothing more than an inexplicable inverse-square attractive force.

Re:A Physicist Who Denies Dark Matter by electrograv on Saturday May 20, 2017 @11:32AM (#14382832)
If a Newtonian model of gravity doesn't "explain" gravity, then neither does general relativity. These are all different models of reality with different levels of model complexity and predictive accuracy, but there's no fundamentally binary difference between them in their power of "explanation" etc.

So new models like "dark matter" or "MOND" are all just different models that model observations better than prior theories but currently have the problem of being difficult to unify with the rest of theoretical physics.

Re:A Physicist Who Denies Dark Matter by olavk on Saturday May 20, 2017 @11:31AM (#14382824)
There was/is nothing magic about epicycles. Epicycles was part of a model which described the movement of the planets. Now we have better and more precise model, but that does not mean epicycles was "magic".

There is nothing magic about the the word "dark matter" either. Yes indeed it describe a phenomen we don't understand, this does not mean it is magic.

Re:A Physicist Who Denies Dark Matter by TillE on Saturday May 20, 2017 @11:34AM (#14382839)
Epicycles were wrong. They were an incorrect theory attempting to fit the math.
Re:A Physicist Who Denies Dark Matter by yorwba on Saturday May 20, 2017 @12:09PM (#14383027)
Using epicycles just means to decompose the motion into its Fourier series. It may not be the most elegant description, but its not wrong per se, either.
Re:A Physicist Who Denies Dark Matter by JadeNB on Saturday May 20, 2017 @07:56PM (#14385027)
> Using epicycles just means to decompose the motion into its Fourier series. It may not be the most elegant description, but its not wrong per se, either.

One issue here is that (as I understand the history) epicycles were not originally proposed in the context of "just add them until you've got something that looks right"; it was proposed that, occasionally, one needed to add one epicycle. After a while it was found that even this didn't work, and we needed sometimes to add another. I forget whether the theory collapsed before instances were found where we'd need a third.

This, I think, is 'wrong' in the sense of physics: if your model is constantly scrambling to catch up with newly acquired data, then it has no predictive, and hence little scientific, value. Further, the very ability of epicycles constantly to scramble to catch up—the ability of trigonometric polynomials to approximate continuous functions arbitrarily well over arbitrary bounded intervals, as you mention—is also a mark against them: a scientific theory that is so general that it could be tuned to predict anything can, in fact, for that reason actually predict nothing.

Re:A Physicist Who Denies Dark Matter by olavk on Monday May 22, 2017 @02:41AM (#14391463)
Epicycles were added to make the model better fit the observations. There is nothing wrong or unscientific about this. It is just like new planets are added to the model of the solar system when new planets are observed.
Re:A Physicist Who Denies Dark Matter by JadeNB on Monday May 22, 2017 @03:03AM (#14391546)
> There is nothing wrong or unscientific about this.

To be sure, there is nothing wrong with changing your model in response to data—what would be wrong would be the opposite. What I was calling 'wrong' was two things: (1) a model that can only be tuned post hoc to observations (that is, it's always being changed to fit them, and never predicting new ones); and (2) a model that is so flexible that it can be tuned to fit any observations (again, because it will never have the ability to predict future observations).

Re:A Physicist Who Denies Dark Matter by olavk on Monday May 22, 2017 @07:44AM (#14392720)
The predictions by the system is the movements of the planets in the sky. The Ptolemaic system with epicycles actually did this pretty well, considering the available data. It is just that as better observations and better calculations became available, the model have to be more precise which required more epicycles.

I don't really get the thing about "too flexible". According to Wikipedia there is apparently some myths floating around regarding the science history of epicycles, but I assure there is nothing magical about them - at least they are not any more magical than Newtonian mechanics.

Re:A Physicist Who Denies Dark Matter by JadeNB on Monday May 22, 2017 @08:24AM (#14392943)
> I don't really get the thing about "too flexible". According to Wikipedia there is apparently some myths floating around regarding the science history of epicycles, but I assure there is nothing magical about them - at least they are not any more magical than Newtonian mechanics.

I think we may be talking at cross purposes here, but I wanted to give it another shot. I do not think that there is anything magical about epicycles, and my objection to them is scientific; it has nothing to do with their history. My claim is that a scientific tool is valid science only to the extent that it has predictive power. If your model has so many parameters that, by setting them to appropriate values, you can fit any outcome, then (absent some other data telling you which values of the parameters to use) you'll never actually predict anything, only scramble setting them to 'post-dict' existing observations—which is, effectively, useless.

(For example, any finite collection of observations can be 'post-dicted' by a high-degree polynomial, and we can accommodate more observations simply by increasing the degree of the interpolating polynomial. This is not magical, and mathematically totally sound; but its very flexibility means that it is scientifically useless, because there's no reason to believe that our perfect fit to the `n` values we've seen so far says anything about the (`n + 1`)st value we'll see next.)

Re:A Physicist Who Denies Dark Matter by olavk on Monday May 22, 2017 @01:31PM (#14395425)
OK how is it you think epicycles differ in this respect from say the keplerian model of the solar system? I struggle to understand what you think is "special" about epicycles. No model of the solar system will allow you to predict the movement of the planets if you don't enter the correct parameters, which you have to find through observation. Given the correct initial parameters, the ptolmaic system with epicycles will yield predictions about the movements of the planet, predictions you can verify or falsify through observation.
Re:A Physicist Who Denies Dark Matter by JadeNB on Monday May 22, 2017 @08:59PM (#14398045)
> OK how is it you think epicycles differ in this respect from say the keplerian model of the solar system?

Just to be clear, I'm not in any way insulting the intelligence of those who proposed them. It was a clever mechanism for dealing with what seemed at the time to be a blemish on an otherwise beautiful theory, and the fact that it turned out to be (factually) wrong does not mean that it was wrong to propose and test it.

With that said, here's my stab at what I see as the difference. The Keplerian model predicts elliptical orbits. To be sure, one must do some tuning of parameters to find the semimajor and semiminor axes of these ellipses; there is no way for someone sitting in a windowless room, with access only to Kepler's laws, to predict exactly, say, the length of a Jovian year, or even the existence of Jupiter.

However, what is crucial is that that person sitting in a windowless room can say, definitively, that, if Jupiter has been observed in these five positions at these five times, then it will be in this position at this sixth time. If it's not there, then the Keplerian model is wrong; it has been falsified.

Now suppose instead that another person in another windowless room knows about, not just Kepler's laws, but also epicycles. Given the same five measurements, he or she can make a prediction (which won't require epicycles). This prediction might or might not agree with the sixth measurement, but, if it doesn't, then that's no problem; just add on an epicycle to account for that measurement. If the result of that correction doesn't agree with the seventh measurement, then just add another epicycle.

To me, these two systems are meaningfully different. It is not the reliance on parameters to which I object, but the extreme flexibility; a model that can literally never be falsified, because it can always be adjusted to match new observations, is worthless as a scientific model.

Re:A Physicist Who Denies Dark Matter by olavk on Tuesday May 23, 2017 @02:04AM (#14399140)
That would be a valid criticism if epicycles were added to the model post-hoc to explain previous observations, and adding those epicycles to the model did not improve future predictions.

Is that really how you think epicycles were used?

Re:A Physicist Who Denies Dark Matter by JadeNB on Tuesday May 23, 2017 @03:11AM (#14399421)
> Is that really how you think epicycles were used?

Yes. So, if that's not true, then you've been right all along, and my objection was mostly founded on a misunderstanding of the history. Do you have a reference I could read?

(I should say that, even if it's not actually how they were used, it's still how they could have been used, and I think that the spirit of my objection applies; but the actual practicalities of it would certainly be undermined by my historical misunderstanding.)

Re:A Physicist Who Denies Dark Matter by olavk on Tuesday May 23, 2017 @05:28AM (#14399959)
In short: Before the Ptolemaic system, it was assumed the planets moved in circular orbits around the earth. The problem is, this did not explain the phenomenon of "retrograde motion", which is when a planet apparently slows down and moves backwards in its path over the sky, as observed from the earth. Ptolemaus added the epicycles which describes the planets as additionally moving in smaller orbits along the path - just as the moon moves in a smaller circle around the earth, which would result in retrograde motion if observed from the sun. In other words, the epicycles explained a phenomenon and allowed the model to better predict the future movements of the planets.

The thing is, this model is not wrong and makes reasonable correct predictions about the motion of the planets as observed from the earth. The Copernican model is just simpler because by describing the planets as orbiting the sun rather than the earth, you don't need as many epicycles in the model. The Tychonian model, by the way, solves the same issue by having the planets orbit the sun, but the sun oribiting the earth, thereby additionally solving the parallax problem which the Copernican model could not explain given the knowledge at the time. All three models needed additional epicycles, which Kepler simplified by describing the orbit as a elliptical.

You will note these models are actually equivalent in modern understanding, where neither the sun or the earth is at the center of the universe.

The current model of the solar system still have epicycles (eg. for moons), so if the presence of epicycles somehow turns a model into pseudoscience, then what?

Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @07:51PM (#14385014)
This should not be downvoted
Re:A Physicist Who Denies Dark Matter by wayn3 on Saturday May 20, 2017 @10:58AM (#14382660)
And that's exactly what dark matter is.

Journalism misleads people very hard about physics research. Physicists dont run around claiming they've observed dark matter. That's the wrong direction. Physics has a problem with gravity because some things don't behave in such a way that makes theory agree with observation. Since we are talking about gravity here, we call the thing we are observing "matter". Simply because things that interact with gravity have historically been called matter. Because its "dark" in the sense that we can't see (observe) it, its called dark matter. As a placeholder for something that has not yet been explained.

Then journalists come around and spin this tale about how physicists have found this super magical stuff called "dark" "matter" and its so exotic if you dropped it onto des moines it'd turn the place into honolulu.

Dark Matter is just the placeholder name for an observation that disagrees with conventional theory.

Re:A Physicist Who Denies Dark Matter by roywiggins on Saturday May 20, 2017 @11:12AM (#14382725)
But dark matter is theorized to he a particle that we haven't observed yet, which sounds like "matter" to me. The specific idea to fix up the discrepancies is, there are huge clouds of invisible particles. There are competing theories on what sort of particle they might be, but dark matter theories predict that these particles are out there.
Re:A Physicist Who Denies Dark Matter by wayn3 on Saturday May 20, 2017 @11:22AM (#14382766)
again, thats what theoretical physicists do. Someone makes a weird observation and your theory is left with a hole. You try to plug it.

They don't preach these things. Physicists don't run around preaching unprovable holy grail theories. They just make something up. Out of nothing. Because its their job. They need to come up with falsifiable theories that can be verified in lab experiments.

In order to do so, they HAVE TO hypothesize something. They can't just say "err dark matter right?". They have to say "there could be a particle with these properties, a mass of roughly X, producing a cross-section of Y when bombarded with tau-leptons etc.". That's just the scientific method.

Any physicist who postulates particles does that from a position of "it probably doesn't exist". The same way when you measure something to be faster than the speed of light, you assume that a cable is broken.

Then some journalist comes around saying "lol paper says weird particle exists, scientists are whack". That's annoying. But it happens.

If journalists wrote about CS the way they write about physics, the next time someone loses 2 BTC from their wallet, they'd claim that thats hard evidence of quantum computers being invented by north korea. Hypothetically plausible but as outlandish as permissible by reality.

Re:A Physicist Who Denies Dark Matter by pharrington on Saturday May 20, 2017 @12:51PM (#14383209)
Dark matter isn't theorized to necessassrilly be a particle either (finding new symmetries in the standard model would be extremely surprising)- it's literally just a placeholder name for a massive (as in, exhibits mass) unknown.
Re:A Physicist Who Denies Dark Matter by roywiggins on Sunday May 21, 2017 @12:12AM (#14385663)
Dark matter theories absolutely do theorize invisible mass-bearing particles.

https://en.wikipedia.org/wiki/Dark_matter#Composition_of_dar...

It might be ordinary matter hidden from us somehow (maybe inside black holes) or something new like sterile neutrinos or WIMPs.

Re:A Physicist Who Denies Dark Matter by pharrington on Sunday May 21, 2017 @12:40AM (#14385722)
Yes, one way to restate my post is that dark matter could or could not be a new particle. The important part is that dark matter proponents assert there is something(s) whose mass we can detect, but whose other properties we can't measure as it doesn't fit into our current physical models.
Re:A Physicist Who Denies Dark Matter by jrvidal on Saturday May 20, 2017 @12:40PM (#14383157)
Re:A Physicist Who Denies Dark Matter by laretluval on Saturday May 20, 2017 @11:06AM (#14382699)
Re:A Physicist Who Denies Dark Matter by douche on Saturday May 20, 2017 @12:18PM (#14383067)
Whoo, boy, the astrophysics fanboys that come out of the woodwork to suppress the notion that the emperor has no clothes
Re:A Physicist Who Denies Dark Matter by jcranmer on Saturday May 20, 2017 @02:05PM (#14383532)
Even as someone who would rather MOND be true than dark matter, I have to admit that dark matter is internally consistent in ways that MOND is not.

By comparison to the theories of planetary movement (since you seem to love comparing dark matter to them so much), MOND is rather like the Copernican model and dark matter rather like Kepler's model. It's well-known that the traditional equations are off. MOND provides a fix that starts off looking better, but the more precise you do the measurements, the more you need to add the fudge factors in to make the numbers come out right, and it ends up being just as bad as the original--which is a reasonable description of the evolution of the Copernican model. By contrast, both Kepler's model and dark matter provide a much more accurate picture with a somewhat more complex addendum to the original non-fudged equations. But they also both lack mechanistic explanations for their origin: Kepler's model ruined the traditional explanation of how planets moved and inherited the stellar parallax death-knell from Copernicus's theory.

In the case of planetary motion, it took the development of Newton's Law of Gravitation and the derivation of Kepler's laws of planetary motion from said theory to provide a sound mechanistic basis. We lack that mechanistic basis for dark matter, but that doesn't really mean that dark matter is inherently wrong.

Re:A Physicist Who Denies Dark Matter by nilson on Saturday May 20, 2017 @03:01PM (#14383780)
Why do physicists believe that formulas should be elegant, beautiful etc.? Maybe that is not how universe works.