Do Dark Matter and Dark Energy Cast Doubt On the Big Bang? 225
StartsWithABang (3485481) writes "Back in the 1960s, after the discovery of the Cosmic Microwave Background, the Big Bang reigned supreme as the only game in town. But back then, we also assumed that what we consider as "normal matter" — i.e., protons, neutrons and electrons — was, along with photons and neutrinos, the only stuff that made up the Universe. But the last 50 years have shown us that dark matter and dark energy actually make up 95% of the energy composition of our cosmos. Given that, is there any wiggle room to possibly invalidate the Big Bang?"
Oh good lord. (Score:5, Informative)
There's always the possibility of a theory being falsified but in this case the answer is almost certainly no.
The big bang is not going to be invalidated, so say COBE, WMAP and PLANCK.
Also, it's actually less than 5% baryonic matter it seems, 4.4%
http://map.gsfc.nasa.gov/unive... [nasa.gov]
Be aware that dark matter is just matter we can't directly detect with our current technology (or just haven't /yet/), it's not something magical.
Oh good lord. (Score:5, Informative)
Well, the fact that we can still hear the universe ringing at the exact range and frequency curve predicted by George Gamow nearly twenty years before Wilson and Penzias "discovered" it (see the cosmic background radiation - look it up), I'd say no.
Also, the farther out we look, the faster galaxies are moving away from us. Run that backwards in time and we're all in the same place about 13.7 billion years ago. Again, I'd say no.
Also, the balance of H, He and Li that was predicted...
Also, the evolution and make-up of stars and proportions of heavy elements in near and far galaxies...
Etc. etc.
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Re: "when you make theories to fit your observations, of course they match."
Slashdotters appear to generally not realize that scientists simply decide what anomalies to focus the public's attention on. Notice that this article never mentions any uncertainties associated with these ideas, nor areas where potential mistakes might exist within these conventional theories. Why even broach this subject if you're not at all willing to give the critics some airtime to make their case?
The people who run this site
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I'd say that, if you made theories that didn't fit your observations, they wouldn't be much use. Of course, to be a real scientific theory, it has to make predictions of things we haven't yet observed.
Scientists aren't generally in the business of focusing the public's attention. They focus on anomalies because that's where the interesting stuff is. Science mainlines criticism. The best way to make a big name for yourself is to come up with a theory that attracts a whole lot of criticism and survives
Re:Oh good lord. (Score:4, Informative)
A. What part of Gamow's ABC paper was "make theories to fit your observations"??
He published a paper on April 1st, 1948 with Ralph Alpher and Hans Bethe (Alphar - Bethe - Gamow... get it?) on Big Bang nucleosynthesis that explicitly stated that if there had been a Big Bang, that you still would be able to detect a black body radiation light curve from the first moments that the cosmos expanded (cooled) enough to allow photons to survive. Alpher soon calculated that the peek would be below 5 degrees by now.
Radioastronomers couldn't be bothered to check this out - it wasn't until 1964 that W&P (not radio astronomers) were trying to fix a "noisy" antenna that this was discovered. They got a Noble prize for this, which should have also gone to Alpher and Gamow.
B. That you say "And no, if you run that backwards it doesn't work out that its all in the same place." shows that you're thinking of the Big Bang as an explosion - as if you were observing it from outside. This isn't correct at all - everything you are, and the stars and galaxies are part of the cosmos. Two weeks ago - most galaxies were millions of miles closer - i.e. the cosmos was more dense. A few months ago - a few billion miles closer - more dense still. 13.7 billion years ago all the matter/energy OF the cosmos was so close - so dense and hot that there was a hot particle soup - that locally some galaxies are coming together due to gravity rather than spreading apart is irrelevant.
It's like saying - all the cars on the road couldn't be from a factory - they're all going different directions!
Re:Oh good lord. (Score:4, Insightful)
First of all, aspects of big bang cosmology were predicted before observation, and second of all, WTF? Theories have to fit observation or they are, by definition, wrong.
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"Settled science" is stuff that we're pretty darn sure of. Consider it as proven for now beyond reasonable doubt. That doesn't mean that somebody isn't going to show up next week claiming that this theory satisfies the observations better and predicts such and such, but it does mean that it's going to take some pretty convincing evidence.
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You should probably read up a little more on how hypothesis formation works. You can either base it on experiment, or you can base it on, say, what math says should be there.
But it's just hypothetical until it is shown to conform to reality with a certain degree of certainty.
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Sigh, when you make theories to fit your observations, of course they match.
And how, pray tell me, should we be making our theories, if not to fit our observations (facts and evidence)?
The problem is when people try to distort (or ignore) facts to fit their theories. Or when people aren't willing to revise or discard their theories when presented with new facts.
Doesn't make them any more correct
Of course it does. More than that, that is the exact definition of a theory being correct: matching the facts.
It is the the theory doesn't match the observations (facts and evidence) that it is incorrect, and needs to be rev
Invalid hypothesis (Score:2)
Re:Oh good lord. (Score:5, Interesting)
And maybe dark matter isn't at all, but just a matter (bad pun, I know) of our misunderstanding of something.
Take the planet Vulcan [wikipedia.org]. No, not THAT Vulcan. But also a fictional one. Astronomers noticed Mercury isn't circling the Sun as it should, so something had to account for this. In their understanding back then, there had to be another planet that causes that. But then uncle Albert came along and explained it with relativity and now we know that gravity is the culprit, not some planet we can't see.
What if this is a similar case? Like, say, (normal) matter having gravity properties that only become noticeable on a cosmic scale? Like, say, relativistic effects that take a DAMN LOT of gravity to become noticeable?
I'm not saying it is so, I just wonder if we're dead set on Dark Matter or whether we're actually still looking in other directions? Or rather, whether serious scientists actually look into different options aside of Dark Matter to explain the discrepancies, not just crackpots and snakeoil peddlers.
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Dark matter is probably just civilizations that have built (advanced forms of) Dyson spheres around their stars.
This also explains the Fermi paradox.
Re:Oh good lord. (Score:5, Insightful)
Dark matter is probably just civilizations that have built (advanced forms of) Dyson spheres around their stars.
This also explains the Fermi paradox.
Dyson spheres would glow in the infrared and therefore be pretty obvious. This is because they still have to radiate the heat produced by the star they enclose - otherwise their internal temperature would perpetually increase.
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Isn't that purely supposition?
Because, by the time a civilization has the technology to build a Dyson sphere ... we really have no of what else they would be able to do.
Building a Dyson sphere sounds like it involves engineering challenges well beyond anything we can even imagine.
So, I
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Why would they specifically glow in the infrared?
I know that the infrared spectrum glow for dyson spheres is popular in science fiction literature, but I never understood the fixation on that particular part of the em spectrum. Why not something colder, like microwave radiation?
That's an interesting theory. At the moment, we don't really have means to extract additional energy from waste heat, so it ultimately radiates off as infrared. But if we're seriously considering building a Dyson sphere, one supposes we've already exhausted every possible efficiency we can come up with, including reducing infrared wavelength all the way down to microwave wavelength, squeezing every last possible watt out of it.
It doesn't seem likely. Black body radiation at room temperature and cooler is
microwave bright [Re:Oh good lord.] (Score:4, Insightful)
well, if Dyson spheres are anywhere near the size of the solar system, they would radiate in the infrared. Longer infrared the larger they are.
You could imagine a Dyson sphere that is vastly larger than a solar system -- like, a hundred AU across, or so--that would radiate waste heat in millimeter wave, or even something vastly larger than that that would radiate in microwave.
But, of course, that doesn't solve the problem-- they would be shine like beacons to radio telescopes.
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Except that according to Wikipedia the cosmic microwave background [wikipedia.org] peaks at around a millimeter, so the super-sized Dyson sphere would absorb more than it radiates. Also, we need to remember that a diameter 50 AU Dyson sphere won't get any more energy than a 2 AU one, it'll
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Well, I didn't say it was a good idea.
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2nd law [Re:microwave bright [Re:Oh good lord.]] (Score:2)
If a civilisation could create a Dyson sphere, don't you think they'd have some use for all the wasted energy "radiating in infrared"?
If they can get usable energy out of waste heat, they have a means of getting around the second law of thermodynamics. It's hard to guess what a technology with that much sophistication can do, but if they can do that, they don't need to surround a star with a shell to harvest energy.
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If a civilisation could create a Dyson sphere, don't you think they'd have some use for all the wasted energy "radiating in infrared"?
If they can get usable energy out of waste heat, they have a means of getting around the second law of thermodynamics. It's hard to guess what a technology with that much sophistication can do, but if they can do that, they don't need to surround a star with a shell to harvest energy.
In one of Stross's novels, it's computonium, a material that absorbs energy and uses it as computational power. The sun is surrounded by successive layers of Dyson spheres with each outer layer absorbing the waste heat of the layer inside of it and radiates off increasing wavelengths of radiation. Subsequently, each outer layer runs at a slower rate than those father towards the interior and are the slums of the virtual society that exists inside all those layers of computonium.
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Heat is a waste product, efficient energy use doesn't necessitate heat.
Not sure if I'm feeding a troll now, but, yes it does. "Using" energy specifically means transforming it such that the entropy increases. The energy doesn't disappear, you can only change its form. And the form where it has the highest entropy (i.e. where you have extracted all useful work), is heat.
All a Dyson sphere does is exploiting the energy difference between its interior and its exterior. All the energy passes through it; the sphere just maximises the entropy as it passes through, in order to perfor
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Wow, the self-important, self-certain ignorance is really rank.
You seem to be conflating a bunch of different things, then waving your hands and shouting "impossible." Impossible is the idiot's way of saying, "I don't know the answer."
If you have heat, you have useful energy. Period.
Entropy goes up in an isolated system that contains irreversible processes. But no process is irreversible, given the precondition of an intelligent race with advanced technology. The only reason entropy "has to" go up in the st
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That accounts for the second (well, not really, but let's not go there yet), but what about the first law of thermodynamics? You have a star in the middle of the system, constantly converting H to He and releasing the binding energy thereof, hence increasing the energy level of the system. How do you keep an equilibrium if you don't radiate?
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Where is this magical free energy coming from? Energy is conserved. If you're not radiating, it means you reused everything already, so of course nothing increases.
You're probably confusing the thought experiment, and forgetting that that conversion can be reversed, as can they all.
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Dark matter is probably just civilizations that have built (advanced forms of) Dyson spheres around their stars.
Are the Dyson spheres so they can suck up all the cosmic dust?
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Well, dyson spheres seems a bit implausible unless there are a TON of them, and they're not actually invisible as they would radiate waste heat - they'd appear as IR black bodies.
However, if they were invisible I'd think they'd be consistent with the bullet cluster image. That image showed that intergalactic gas interacted during the collision, but dark matter did not. I wouldn't expect large objects like stars to interact the way that gas would. If you point a fan into a room full of air, you'll feel a
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Hate to self-reply, but by TON of them, I mean that 95% of the stars in the universe are actually inhabited by intelligent life who have built dyson spheres, and everything we see are just the remnants that they haven't bothered to settle, which seems rather unlikely to me.
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To be honest I'm not sure about the mass of a Dyson sphere. However, I'd assume that estimates of the amount of baryonic matter already take into account the non-steller mass associated with a typical solar system, so if the estimate is that we need N stars to account for it, we'd need N Dyson spheres since those spheres could only be constructed from the matter around the star. That is, unless they disassemble a few stars to provide matter to produce a sphere around a different star.
In any case, they wou
Re:Oh good lady, and lord. (Score:5, Insightful)
we'd like to have non-baryonic fairly massive (so relatively cold) particles. Dark matter is anything that doesn't interact with regular matter via the strong or gravitational interactions. Neutrinos don't.
More and more I'm getting a feeling that science has been down this road before. That our understanding of subatomic particles and the distant edges of the Universe is similar to the pre-Copernican use of epicycles to understand astronomy. That the search for dark matter (and probably string theory too) is a search for that final missing epicycle that will make the model work just right.
I think we need to look for a Galileo or Copernicus who has some whacky, undeveloped alternate concept that if only we could change our point of view, we would see that it makes everything so much more clear.
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On the other hand, perhaps it's like the neutrino. fusion (or fission, I forget) equations didn't work out so as a fudge the neutrino was invented, a super small particle that didn't interact with normal matter.
I'm sure it was met with derision by a certain group, an imaginary particle that could travel through the Earth, how ridiculous and obviously the idea of fusion was wrong in some fundamental way.
Well eventually the neutrino was observed, mostly matching up with theory (it was actually more complex, c
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More and more I'm getting a feeling that science has been down this road before. That our understanding of subatomic particles and the distant edges of the Universe is similar to the pre-Copernican use of epicycles to understand astronomy.
It's certainly possible that we're merely stumbling about to find a better theory, but I think the epicycles analogy is generally a bad one -- it was good science back in the day, based on what was "known" about the universe at the time. Now we know better, because we've figured out that some of the fundamental assumptions of the old model were wrong, but good scientists of the day had no way of knowing some of those things were wrong (and in fact had some good evidence that those things were right -- like
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There was no final epicycle that made the predictions right. On the other hand, if there's lots of matter that doesn't interact with anything electromagnetically, that would explain a lot of things nicely. It would explain galactic rotation curves. It would explain places where we have gravitational lensing without visible matter (consider the Bullet Cluster in particular). It would explain certain predictions of the Big Bang theory.
I have no idea why people have so much trouble with the idea. Basic
Re:Oh good lord. (Score:4, Interesting)
Dark matter was there in todays proportions in the hot early universe, so no. All the MACHO theories went by the wayside with the CMBR data, it's WIMPs now for sure.
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Analogy: you are in a dark room full of people with sparklers, but you know there are some without them because somebody without one just stood on your foot.
Re:Oh good lord. (Score:4, Funny)
That wasn't a person without a sparkler, that was a grue.
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This guy has a very good video showing why we don't need the big bang or dark matter/energy to explain the state of "known" universe.
https://www.youtube.com/watch?v=oy47OQxUBvw
The Bullet Cluster Makes it Unlikely (Score:5, Informative)
What if this is a similar case? Like, say, (normal) matter having gravity properties that only become noticeable on a cosmic scale?
Models like this have been considered such as MOND (MOdified Newtonian Dynamics). These models were largely shot down by the aptly named Bullet Cluster [wikipedia.org]. This is a system of two galaxies colliding at a high relative speed. The gas from the smaller "bullet" cluster collides with the gas in the larger cluster causing it to slow down, heat up and emit X-rays so we can see it.
So far so go. However you can also look at the mass distribution by seeing how it distorts the light from galaxies behind the cluster (this is called gravitational lensing). This shows that most of the mass of the smaller cluster has not slowed down and is now separated from where all the gas in the cluster is located. Effectively the collision has separated the matter from the dark matter because, unlike normal matter, dark matter has a tiny cross-section for interacting with itself or other matter. This is exceedingly hard to explain by modifying the behaviour of normal matter since you are observing a gravitational field where there is no normal matter.
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MOND can't explain the CMBR data at all, while dark matter, WIMPs specifically, predicted the observed proportions accurately.
So we know now: dark matter is there, it's ~80% of matter, and it's WIMPs not MACHOs. String theory predicts a family of 1-plank-mass-ish particles - just one more untestable string theory claim, but it would fit dark matter pretty well. If we ever actually build a dark matter detector that works, the worst might happen: we might have to start taking string theory seriously too! E
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Re: "Models like this have been considered such as MOND (MOdified Newtonian Dynamics). These models were largely shot down by the aptly named Bullet Cluster"
Have you considered that there is more than one possible interpretation for the Bullet Cluster?
At this point, while there might be some sort of MOND out there to describe what is going on, currently it would be such a bizarre and complicated theory that nobody can come up with a theoretical set of equations that fits current observational data, let alone could be otherwise tested. And trust me, there are plenty of grad students and other people working on the issue, that would love to find such and get their Nobel if not just playing with it as a mental exercise.
Oh good lord. (Score:4, Interesting)
We're finding it quite easy to directly detect its affects with our current technology - it's called a telescope. We just have no clue as to what it is or how it works.
I'd like to point out that gravity is in the same category. Also time.
We do know a lot more about light and electricity. Please check out "QED" by Richard Feynman. Well we actually don't know how that works ether, but we've figured out the math to make very precise predictions that usually match reality so we must be on the right track.
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Please check out "QED" by Richard Feynman. Well we actually don't know how that works ether, but we've figured out the math to make very precise predictions that usually match reality so we must be on the right track.
Indeed, QED is the most successful theory that man has ever formulated, and Feynman was IMHO far greater than Einstein or Hawking.
When the first shuttle blew up, NASA picked up the phone and called Feynman, someone that never did anything for NASA before and was not involved in any way with the shuttles, rockets, or even anything astronomy. Feynman figured out what happened quite quickly, went before congress and both explained and demonstrated the problem.
Einstein has a brilliant idea. Hawking had a b
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Indeed, QED is the most successful theory that man has ever formulated
No, actually that would be special relativity which has been tested to around 20+ orders of magnitude by cosmic rays [arxiv.org] as well as (arguably) tests of CPT symmetry [wikipedia.org] which last time I checked (quite a while ago) was at about 18 orders of magnitude.
QED is 'only' at about 12-14 order of magnitude of accuracy (which is extremely impressive!). Indeed since QED incorporates Special Relativity it would be hard for it to be tested more accurately that SR since any test of QED is, by definition, a test of SR as well
QED relies on Special Relativity! (Score:2)
Irrelevant to weather it is a success or not. You seem to think that success means 'measured to within a certain accuracy'
Yes actually that is precisely what it means for a scientific theory. The aim of a scientific theory is to model the behaviour of the universe therefore the most successful theory is the one that most accurately describes the universe's behaviour.
Relativity doesnt hold a handle to that. Not even close. Aside from GPS satellites, how has our understanding of relatively improved your life?
Leaving aside that you appear to be confusing Special Relativity with General Relativity, QED requires and relies on special relativity. Hence anything which QED gives us would not be possible without special relativity. You also seem to be confusing QED with qua
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Indeed, QED is the most successful theory that man has ever formulated, and Feynman was IMHO far greater than Einstein or Hawking.
Please. Annus Mirabilis papers [wikipedia.org]
That's four groundbreaking papers in one year (1905), any one of which would have made Einstein of historical significance. To follow that up with the only major advance on gravity since Newton 10 years later puts him well past Feynman.
When the first shuttle blew up, NASA picked up the phone and called Feynman, someone that never did anything for NASA before and was not involved in any way with the shuttles, rockets, or even anything astronomy. Feynman figured out what happened quite quickly, went before congress and both explained and demonstrated the problem.
He did good work on the panel, but it was hardly a big mystery as to why the launch failed. There was actually a conference call the night before the launch between NASA and the manufacturers of the O-ring. The latter wanted to scrub the launch b
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Allow me to paraphrase your comment.
"My subjective assessment is different than yours, but I'm so insecure about not being able to prove subjectives that I'm going to call your viewpoint names."
Was Feynman a better showman than the other people who also came up with working math for QED? Yes.
Einstein was also a great showman, who is widely believed to have stolen some of his theories from his first wife. Einstein is legendary as a showman, if you actually are interested in these sorts of non-science details
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Allow me to paraphrase your comment.
Allow me to paraphrase your comment: I'm a jackass who thinks nothing substantial can be said when opinion counts, even when the accomplishments are well-documented and acknowledged by the larger scientific community. I also entertain spurious allegations about Eisenstein having plagiarized his wife, which has no credible evidence.
Re:Oh good lord. (Score:5, Interesting)
We just have no clue as to what it is or how it works.
I'd like to point out that gravity is in the same category. Also time.
This.
When Newton was first discussing his theories of universal gravitation, the scientific community was rather skeptical, because it invoked spooky "unseen forces" acting at a distance (i.e., gravity). The previous Aristotelean model of physics asserted that "normal" terrestrial matter came to a nature place of rest (earth sinks down to equilibrium, air rises to equilibrium, etc.), since Newton's first law hadn't been realized yet. Instead, real-world friction, etc. tends to bring things to a state of rest, which accords with everyday experience. All motion had to be explained by a "cause," something that propelled it into motion, and ultimately the matter would stop moving once it came to its natural state of rest.
The motion of the planets could not be explained using this physics, so the celestial bodies were assumed to be of a different type of aetherial matter (or something) which was set in motion at the beginning of time or something.
That was the proper scientific theory of the day, and it accorded with empirical observation and common sense -- terrestrial bodies stopped, celestial ones seemed to go in continuous motion forever.
But Newton came along and equated the two -- and he developed a mathematics that described the motion. Unfortunately it depended on a "spooky" occult idea of forces acting at a distance. (Newton, of course, was really into the occult, alchemy, etc.)
So, scientists of the day were skeptical. Newton eventually even published an appendix with future editions of the Principia explaining that his model didn't depend on "real" unseen forces acting -- instead, he basically came up with the modern scientific ideal that says: if the math works and predicts the phenomena, that's enough for science. A scientific model need not be concerned with philosophical questions or ultimate causes of phenomena as long as it can actually make good predictions.
THAT, probably more than anything else, was the foundation of modern "science" laid down by Newton during the Scientific Revolution. People had been doing experiments and empirical investigations for millennia, but they always had to worry about ultimate "causes," which inevitably depended on somebody's pet theory of reality. After Newton, though, what matters is that the math works. Maybe the dark matter/dark energy model is hinting at some deeper aspect of reality and a more elegant theory that we will come up with many years from now... or not. But regardless, these ideas are exactly like Newton's "gravity" -- something which we observe, something we can have an accurate mathematical model of, but also something "spooky" that we don't understand completely yet.
That's what the modern scientific process is all about.
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Certainly yes (Score:3)
Part of the issue here is that the question is ambiguous. "Big Bang" has morphed and changed into may forms in the last century+ when it was first envisioned. So, which big bang are you and TFA referring to? The original that said all the mass was a few hundred thousand miles across and blew up? The one taught in the 1970s that all mass was compressed into a ball about 270,000 light years across and blew up? The one that still requires all of the mass to exist already and compressed down to a compact s
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From a logical perspective we have been able to study quite a bit of our solar system hands on, and we have never been able to detect either dark matter or dark energy
So all things that exist, exist within our solar system and are detectable with existing technology? The Higgs boson didn't exist 2 years ago, but exists now? I'm struggling to follow your reasoning.
There were many theories to explain galactic rotation rates: MOND, WIMPs, MACHOs, many more I've forgotten. But out of the whole pack, WIMPs predicted the recent CMBR data accurately. When the math works, and accurately predicts unrelated measurements unknown when the hypothesis was made, well, science means
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So all things that exist, exist within our solar system and are detectable with existing technology?
Not at all, and nowhere do I state any such thing. I do state that logically it's improbable, but not impossible.
If you want to claim that up to 95% of the Universe is made up of dark matter and energy, fine. We can watch geysers on a gas giant's moon, but we can't detect 95% of the space between our Earth and the probe watching? Come now, something is wrong with that claim. Oh I know, someone decided that "dark matter and energy don't exist in our Solar system". Then why is it absent in our solar sy
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If you want to claim that up to 95% of the Universe is made up of dark matter and energy, fine. We can watch geysers on a gas giant's moon, but we can't detect 95% of the space between our Earth and the probe watching? Come now, something is wrong with that claim. Oh I know, someone decided that "dark matter and energy don't exist in our Solar system". Then why is it absent in our solar system?
Dark Energy is everywhere, but the name is terrible. I prefer the old "cosmological constant", even if it may not be constant. All we know about it is that the expansion of the universe is accelerating over time. No idea why or how (or at least stuff that's been explained at my limited level of understanding is just guesswork), but the measurements aren't controversial. And the energy that would be required to cause this expansion, overcoming gravity and all, would be the dominant thing in the universe
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Not only can we not find the dark matter or dark energy...
Look. We just recently mapped the Earth's radiation belts. Oops, they did not match prediction. At all. Not even the right number of belts.
Voyager is out exploring the Solar System's heliopause. Ooops, not as predicted.
That is the recent actual experimental work that has come out of cosmology lately. The rest of it is a lot of hand-waving using edge data points, at scales where nothing can be verified.
Compare that to the work that actual physicists d
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Gravitational lensing does not require either dark matter or dark energy. I find it odd that the NASA link discusses Einstein as the person that came up with the theory, yet fails to mention that Einstein did not theorize these two "dark" things. Gravitational lensing is a result of having curved space and obviously gravity. Dark * is not required nor expected..
Einsteins theory doesn't use gravity at all. It works with mass and energy which cause curved spacetime which then causes gravitational lensing. The dark matter is predicted by this effect because we can't detect enough normal matter to justify the level of light-bending we can observe. Dark matter is also predicted by several other observable phenomena like the speed galaxies rotate around each other or cosmic microwave background.
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Einsteins theory doesn't use gravity at all. It works with mass and energy which cause curved spacetime which then causes gravitational lensing.
The model Einstein had includes gravity, you are skewing how he viewed gravity as a property of mass.
The dark matter is predicted by this effect because we can't detect enough normal matter to justify the level of light-bending we can observe.
Einstein never predicted dark matter or dark energy, so that statement is a complete fabrication. Dark matter and dark energy were "predicted" when models of the "Big Bang" did not work. Stop and think about that for a while.
Dark matter is also predicted by several other observable phenomena like the speed galaxies rotate around each other or cosmic microwave background.
As with above the "prediction" is because our mathematical models of the "Big Bang" and gravity are not working, which means that they are not "predicted" but needed for someone's theo
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And that is what is so sad about science...nothing is magical.
http://xkcd.com/877/ [xkcd.com]
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Not magical? Matter that I can't see and can't interact with? Can you imagine if someone made a drone out of that? A perfect spy device. Nobody can see it, hear it, or knock it down. In fact, I may have one hovering over you right now...
Not so, if you can't see or interact with it, then it can't see or interact with you.
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Just like "Climate Change" , it is "settled" and no further investigation is to be done.
You couldn't be more wrong: it is "settled" and billions of dollars of public research funding are required, or the Earth will die in a fire! Of course, none of that research will be allowed to contradict existing claims, or even question them, but if you think that matters you miss the whole point.
Don't ask me (Score:5, Insightful)
Do Dark Matter and Dark Energy Cast Doubt On the Big Bang?
I have no idea! You should probably ask a physicist.
Re:Don't ask me (Score:5, Funny)
The physicists are the ones asking. We better take this one to the Big Guy Himself.
"So, uh, we were wondering if you could explain why our orbital and rotational predictions for galaxies are not matching our astronomical measurements?"
"They aren't? Are you sure? Let me check the source code. Oh, that's not good. Should have caught that a few billion years ago. This is going to be a real pain to patch. Unless. . . ."
"Unless, what?"
*lightning bolt strikes questioner*
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Given that physicists are seriously studying whether the universe is a computer simulation, that joke might not be too far from the truth. You have been warned.
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If by physicists you mean to include some fringe folk like Tegmark, then sure.
Re:Don't ask me (Score:5, Interesting)
This morning, I was reading about quantum phenomena and how some string theories posit that the length of a string is approximately the Planck length. Strings being the basic quantum unit, nothing can be measured to be smaller than 1 Planck length or measured with more precision than 1 Planck length. What you end up with then, is a universe where the spatial dimensions are a grid, that cannot be traversed continuously, but only in Planck-length increments. In other words - it is essentially digital. Like pixels on a display, where the pixels are much smaller than an atom. My understanding of string and quantum theory (admittedly far from complete) is that all aspects of the universe could be quantized, and thus simulated digitally in a computer.
If anyone can clarify/elaborate/refute, please do.
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I have no idea! You should probably ask a physicist.
You called? The answer is no and we were not really asking this question ourselves since the one of the major pieces of evidence for Dark Matter (PLANCK CMB measurement) relies on Big Bang models!
Low Quality Article, Uses Question Mark. (Score:5, Insightful)
If a headline ends in a question mark the answer is always no. If the answer was yes they wouldn't ask, they'd tell.. The question mark is how shitty opinion pieces trying to push a view point try to masquerade as news.
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If a headline ends in a question mark the answer is always no. If the answer was yes they wouldn't ask, they'd tell.. The question mark is how shitty opinion pieces trying to push a view point try to masquerade as news.
Everything from medium.com is of low quality. They take some nice pictures, put them inline with some artsy text and then say absolutely nothing for several paragraphs. Every article I've read on there has been some made up controversy. "Does dark mater invalidate the big bang?" then 10 paragraphs later "No, not at all" So why exactly did you write this article?
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IS 2+2 REALLY 4?
Well, the concept of "two", or "twoness" is imaginary. It has no physical, chemical, astronomical, or any other scientific qualities. So it is outside the set of things that are "real". "Twoness" only exists in your head; it is at best an artifact of your perception of reality. But such artifacts are not real in themselves.
There is no reason to believe that doubling something that is not real will make it real. That would not be logical. (Invoking the Spock argument.)
Thus "2+2" does not "REALLY" equal "4"
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Betteridge's Law applies to actual headlines, not to sentences which people write up trying to sound like headlines that no article is really using.
Isn't it the other way around? (Score:3, Interesting)
I thought Dark Matter was conceived to account for missing matter that the Big Bang theory predicts needs to exist.
Isn't it the other way around? (Score:2, Informative)
I thought Dark Matter was conceived to account for missing matter that the Big Bang theory predicts needs to exist.
No, it (mostly) came about when it was noticed that galaxies required a lot more mass than was visiible to keep from flying apart. The speeds of stars 'orbiting' was too high, and the things should have flown off. There were other oddities observed as well. All the behaviors observed could be explained if there was a lot more gravitational mass than what could be seen. Some of things seen wer
Re:Isn't it the other way around? (Score:5, Informative)
I thought Dark Matter was conceived to account for missing matter that the Big Bang theory predicts needs to exist.
No, it (mostly) came about when it was noticed that galaxies required a lot more mass than was visiible
It's both, and other observations as well. That's why dark matter is a good theory for the observations we have at this time - several phenomena all point to the same explanation.
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The big bang theory is the part we're confident about. There are observations that imply there are other phenomena happening, and dark matter and dark energy are, so far, the best theories to account for them, but they don't "cast doubt" on big bang cosmology - at best they're likely to lead to minor adjustments.
Now, if something totally new comes along, then we could have a revolution in our thinking and need to come up with a new theory, such as when Aristotle's thinking was replaced with the Galileo/New
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It's not necessarily a new form of energy.
It's possible that there is a 5th force that we don't know about, different from the 4 forces that we already know about (gravity, magnetism, strong force and weak force.)
It could be a very weak force with an extremely long range that only manifests when the other 4 forces are beyond their effective ranges.
On the contrary (Score:2)
It's quite the opposite. You need dark matter and dark energy in order to explain the CMB and the distribution of matter in the Universe. Dark matter and dark energy fit perfectly in the theory, that's the main reason why the alternatives to dark energy/matter that have been proposed were rejected: they fail to explain the CMB and the distribution of matter, while the dark matter and energy explain it perfectly.
Dark matter and dark energy (Score:4, Interesting)
These theories have their own problems. As noted on Slashdot previously, neither exist around dwarf globular clusters or in the local region of the Milky Way. It is not altogether impossible that our models of gravity are flawed at supermassive scales at relativistic velocities, that there's corrections needed that would produce the same effect as currently theorized for this new kind of matter and energy.
Remembering that one should never multiply entities unnecessarily, one correction factor seems preferable to two exotic phenomena that cannot be directly observed by definition.
But only if such a correction factor is theoretically justified AND explains all related observations AND is actually simpler.
There is just as much evidence these criteria are true as there is for dark stuff - currently none.
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It is not altogether impossible that our models of gravity are flawed at supermassive scales at relativistic velocities, that there's corrections needed that would produce the same effect as currently theorized for this new kind of matter and energy.
Sure it is. And very smart physicists have considered this option, among many others.
Remembering that one should never multiply entities unnecessarily, one correction factor seems preferable to two exotic phenomena that cannot be directly observed by definition.
Of course it does. Something to remember is that "dark matter" and "dark energy" are perhaps bad names. They don't necessarily imply that there is something like "normal matter" or "normal energy" out there but is just "dark" (whatever that means). They're just convenient terms to refer to the mathematical "fudge factors" that need to be invoked to explain how things in the universe are actually moving. Whether they ar
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There is just as much evidence these criteria are true as there is for dark stuff - currently none.
Not actually correct. The bullet cluster (see Wikipedia) is extremely hard to explain without Dark Matter. This collision between two galaxies has effectively separated he normal matter from the dark matter so we observe a gravitational field bending light where there is no normal matter. Without Dark Matter you are left with the extremely hard task of trying to explain how a gravitational field can exist where there is no matter.
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Also dark (Score:3, Informative)
The Dark Side of the Moon
No (Score:2)
The answer is no.
TFA says this in about 10 pages, with all the gory details.
Can we try no to have clickbait headlines? TFA is a blog called "Ask Ethan" so it makes sense for the title to be a question. A more appropriate headline here would have been "Dark Matter and Dark Energy don't Impact the Big Bang."
Dark Bang (Score:2)
I bet in a few years, a new theory called "Dark Bang" will replace it.
complete and utter rubbish (Score:5, Informative)
I'm probably a bit biased here, but also an expert, since I am a physicist who studies dark matter for a living.
The title's question doesn't even make sense! Big bang theory, and in particular studying the exact power spectrum of the cosmic microwave background, is by far the strongest evidence we have for the existence of dark matter and dark energy. All those pie charts you've seen showing the divisions of baryonic matter, dark matter, and dark energy? If they're properly cited, I guarantee every single one of them comes from data from WMAP or PLANCK: CMB experiments! You can't say that dark matter gives you room to invalidate the big bang, because without that we don't have really any strong evidence for non-baryonic dark matter in the first place...
Electric Universe (Score:2, Informative)
I would say quite the opposite - that the existence of dark mater and dark energy suggests a possible mechanism for the initial rapid expansion (inflation) without resorting to "magic" forces we have not yet observed.
The electric universe or ionized plasma theory looks great on paper, but the cosmic scale currents and magnetic fields it describes would create easily detectable phenomena which are not actually observed.
I've personally observed a number of Christian astronomers cite "The Big Bang Never Happen
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Dark energy is needed to explain the rapid inflation of the universe. Dark matter is matter we know is out there but can't yet identify because it so weakly interacts with normal matter. One is extremely important to explaining big bang cosmology as we currently understand it. The other in certainly is part of the big bang story, but is as much an interest to particle physicist as cosmologists because it represents the possibility of physics beyond the Standard Model.
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I believe that there is some wiggle room, looking at the electric universe theory.
Actually, Electro-Temporal Unification Theory shows that "electric universe" and "timecube cosmology" make the same predictions at the critical energy density point in 8-space, and is in good accord with all available evidence.
Unfortunately the paper was publised by a certain Jack N. Withya, so most cosmologists haven't bothered to read it.
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Unless it's curvature or a cosmological constant and not energy at all. Then it can manifest quite easily at our scales and observed dimensions. "Dark energy" is one of the more terrible scientific labels out there IMHO because it encourages us to think about this phenomenon in a way that may be totally misleading.
At the moment it's more likely that advancements in AI and understanding of theory of mind will be able to deliver such solution, thru the code and not just pen and paper. It could be that it actually already happened it will just take many years to understand it.
The problem with this is that stuff which is intractable to pen and paper (which is a vast amount of stuff) tends to b
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could we solve current computational problems 200 years ago?
Yes, for small problem sets.
We could say, OK, we could use pen and paper and discover these algorithms out of blue.
And yes, in practice we did use pen and paper (or blackboards, etc) to do just that. Most of the algorithms are easily within the grasp of mathematicians of the past 3000 years (once you get them to accept basic math concepts like real numbers and set theory.
Note that computers didn't make these algorithms possible, they merely created the need for them.
believing that being isolated in the jungle with pen and paper, and no internet, one could formulate dark energy...
Where am I going to find pens and paper in a jungle? The existence of both, particularly of pens with extruded plastics, chem
Re:Dark matter (Score:5, Informative)
As stated below by others, just because it's "dark" doesn't mean it's not just ordinary matter. It's just that we can't actually see it.
Repeating the ignorant doesn't make it true, that "dark matter" is simply ordinary matter we couldn't detect was a good first guess. Very strong evidence indicate it's not [wikipedia.org] because that would create other interactions as well that aren't there. There's some small fraction that is regular matter [wikipedia.org] and some is neutrinos, but without some other form of particles it just doesn't add up.
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We measure and effect and we call that dark matter because it exhibits gravitational effects but we really have no idea what it is or what's causing it. It could be super strings or worm holes or even singularities far from other matter.
This is the problem I have with the entire speculation about Dark Matter, we have no idea what it is. People spend a lot of time talking about it like we know what it is and what it means and all that and it could be nothing more than isolated gravitational anomalies like su
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On weekends?