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The Search for Dark Matter and Dark Energy
mlimber writes "The New York Times Magazine has a lengthy article on dark matter and dark energy, discussing the past, present, and future. 'Astronomers now realize that dark matter probably involves matter that is nonbaryonic ["meaning that it doesn't consist of the protons and neutrons of 'normal' matter"]. And whatever it is that dark energy involves, we know it's not 'normal,' either. In that case, maybe this next round of evidence will have to be not only beyond anything we know but also beyond anything we know how to know.'"
So long as they don't create a black hole somewhere. :)
..."in-transit" energy from 100,000,000,000 stars?
...large amounts of completely non-reflective dust and asteroids?
...a side effect of over-estimating the size of the universe? (i.e. stars like our 5 billions light years away don't exist anymore)
/real questions
//just curious..
+&x
Very large bodies don't behave according to Newton. Very small bodies behave according to the rules of quantum physics, so it's clear that one law doesn't regulate every case. Dark matter/energy are just a fudge factor because we can't explain what happens without them, but that doesn't prove that they exist. All that is proven is that we don't understand what is happening.
From TFA: "Since the invention of the telescope four centuries ago"
I didn't know telecopes were that old. Is this a typo, and didn't they mean decades instead? If not, what did ancient telescopes do?
Please move along.
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And I just got my head around Quantum Physics... Now they are throwing this at me.
I think this might be one of those things I chose not to learn and just leave to someone else.
Curiosity was framed; ignorance killed the cat. -- Author unknown
It's about time someone put some energy into looking at this!
At this point, dark energy is really nothing more than a fudge factor. It's certainly nothing like the normal concept of energy. We don't even know if it's a cosmological constant or if it varies over time and space, let alone whether it's a property of spacetime or some form of particle. So far, I'm still unconvinced that it actually exists: it seems more likely to me that the current theories are simply slightly off in their formulas, and can be resolved without recourse to another of Occam's entities.
ceci n'est pas une
Some questions that spring to mind:
If the grand majority of the 'stuff' in existence around the universe is matter that would be somewhat alien to our range of experiences, could this have an effect on inter-galactic travel? Would what we think it is so far be matter we'd have to worry about hitting and being damaged by at very high speeds?
Is it dangerous? Would it be inert enough that it would be safe for life to come in physical contact with it?
Could it be chemically interesting? Would the interactions with our environemnts' regular organic/metallic molecules theoretically lead to some new reactions or properties difficult to achieve otherwise?
Could it be used in manufacturing or packaging or similar industrial uses if contained? Can it be cheaply collected, once space travel is already assumed as an option?
Ryan Fenton
On the contrary, very large bodies are extremely well-approximated by Newton, as it is the slow-velocity, weak field limit of General Relativity. There is already good photographic evidence for dark matter in the form of colliding galaxies (do your Google work), and current observational evidence points pretty strongly towards dark energy in the form of a cosmological constant. While it's true we don't know what that means, it's not just a fudge factor.
To follow knowledge like a sinking star, / Beyond the utmost bound of human thought. ("Ulysses", Tennyson)
That's an educated opinion, if I've ever heard one.
Karma police, arrest this man. He talks in math. He buzzes like a fridge. He's like a detuned radio.
Ok so i know this is off topic, but why are wild hypotheses like this taken so seriously when things like ESP/human mind altering random probability kind of things laughed at so widely when they actually have many different studies confirming it happens?
There's no money in globally regulating ESP. There's massive amount of taxpayer money to be siphoned off when funding and regulating particle accelerators, nuclear reactors, and telescopic arrays.
The primary driving motive behind 99% of everything which happens in the world: create debt, maintain debt, keep people in debt, work those people until they die from debt.
the NPG electrode was replaced with carbon blac
I'm willing to look like a fool and ask these questions, but I hear about dark matter/energy vs string theory and interesting events like gamma ray bursts and I wonder things but have no one to ask.
- How do they know that the matter is not accounted for?
- Given the absolute vastness of the universe could matter have collapsed into pre-big bang sized chunks very far from each other and things like gamma ray bursts are mini big bangs occuring far away?
This fall I'm going to be taking a physics course and an astronomy course and a decade after dropping out of college I'm actually motivated to learn this time.
If dark matter makes up most of the mass in the universe, wouldn't the kind of matter we're familiar with be the abnormal kind?
Ceci n'est pas une signature.
dark matter = stuff at the bottom of my laundry sucking up available light
...
dark energy = abundant local olfactory distortions generated by the stuff at the bottom of my laundry
mystery solved, case closed
but the science geek side of me wants to see them prove the existence of (not) "normal" dark matter or dark energy because it's just plain cool. and i want my personal teleportation device that skirts the fringes of the space-time continuum!
when it rains, it gets real soggy. when it pours, i'm under the tap just _waiting_ for the joy
... maybe this next round of evidence will have to be not only beyond anything we know but also beyond anything we know how to know. What does that even mean? As if it is so complex we would not be able to understand it if we were given all the details. This sounds like an explanation for God. "God is so beyond our understanding there is no way we will ever understand him. So we might as well just accept and believe in him."hrmmm...
A unique way to learn a language: http://languageloom.com
Or perhaps altic?
Oh, "non-baryonic", I read it as "non-barytonic". Sorry!
-L
...what color dark matter is? God, I hope its not beige.
Cloned foods give the statement "We had that last week!" a whole new meaning.
Because "knowing how to know" is what the word Scientology means. :)
And on that note, no, I'm not a Cult of Scientology member
FTA: "If so, such a development would presumably not be without philosophical consequences of the civilization-altering variety."
Yeah, like my mocha java is going to go up in price, or maybe the prime lending rate?
Good to see that Rumsfeld has found a new job that lets him exercise his poetic skills.
The grass is always greener on the other side of the light cone.
But he was using it in the opposite direction. The parent asked,"How do we know that dark matter isn't just blah blah blah", and the AC replied,"Because we can calculate blah blah blah", and I pointed out that perhaps the calculations were wrong.
I'm not saying that dark matter is or isn't blah blah blah. I'm just saying that relying on calculations to assert that dark matter is or isn't blah blah blah is the wrong approach.
Nobody is saying you can't own a gun, nobody is saying you can't carry a gun... We're just saying you can't carry a gun in town.
the NPG electrode was replaced with carbon blac
God...
* is not "a him".
* is not even "an it".
* doesn't even have a definition that makes sense.
So...
* how can you "believe" in something you cannot accurately describe?
* how can you "believe" in an idea that doesn't make sense?
* Does believing that blue is red make it true?
Does anybody know what they are talking about when they say the word "God"? Because I certainly don't understand what people are talking about when they utter that cobbled word.
Math is our attempt to describe nature. Too many engineering students (and sadly even graduates) are only too happy to plug a bunch of variables into an equation and think they've covered the situation. Basically, interpolation is usually safe and extrapolation is pretty dodgy. At the frontiers of scientific knowledge, applying math is almost always extrapolating.
;-)
The situation with dark matter reminds me of where physics was at the end of the ninteenth century. If you'd asked scientists in 1880 what the frontiers of physics were, they would have told you that things were pretty much wrapped up except for one or two niggling problems. On the other hand, dark matter seems positively reasonable if you compare it with string theory.
BTW. Try calculating the deBrogle wavelength of a galaxy. Hmm. What else do we know that is that small?
Hey, there is still time for you to find out who God is and time to seek.
"I know nothing except the fact of my ignorance."
We will never know everything, and the more we run after knowledge, the farther it will gets from us.
Once (If we ever do) conjure up a decent theory that explains what this Dark Energy and Matter fuss is all about, we will realize that there is even more we don't know than we thought.
This is the curse of knowledge, I for one blame Eve for eating that damn apple.
Heh. Well, then, just send them to the Randi foundation which still has a 1 million dollar prize for anyone who can prove anything like that. The requirements so far have been reasonable too, usually along the lines of having a scientific double-blind test. Nothing you wouldn't expect in normal science. Altering probabilities is even more straightforward, since then you just have to take a large enough sample and do some elementary statistics. So you'd think that if ESP or mind-over-matter or whatever floats your fantasy boat was that proven and working, someone would claim the prize already. But, nah, suspiciously so far what we've had were:
- bullshitters arguing about how unsound scientific testing is, and why they won't take part in it (sorry, if something is only perceived when the test subjects are told and persuaded what they should perceive, then it's probably just make-belief.)
- lame stage magician tricks
- various versions of some global conspiracy to suppress them (funny how noone suppressed them before, then. You'd think the conspiracy would then stop them from publishing books and making faked movies about it too, not just stop them from taking part in a controlled experiment.)
Etc.
Plus, Randi isn't the only one who came up empty so far. What fraudsters are quick to tell you, as if it were some proof of ESP existing, is that both the USA and the USSR were interested in it during the cold war. That much is true. Unsurprisingly, since for example transmitting a message to a submarine by a mean that's (A) not blocked by water or rock, hence receivable from any depth or hole, and (B) impossible to intercept, is any army's or navy's wet dream. What they conveniently ommit there is that both the USA and the USSR, and a few others for that matter, failed to get any results with it.
By contrast, the people with these physics hypotheses tend to actually have some verifiable/falsifiable data, and they give it to you up front. If they did just bullshitting and handwaving like the ESP gang, we wouldn't take them seriously either.
A polar bear is a cartesian bear after a coordinate transform.
Nibbler knows what it is and from where it comes...
It must have been something you assimilated. . . .
Here is an excellent article by Sean Carroll of the California institute of Technology that explains why all the suggestions of the parent post may not be correct.
Basically, what it says is that if two large clusters of galaxies went right through each other, and dark matter was really like the normal matter in the way the parent post suggests, we would get a different result from what would happen if dark matter was for real. Astronomers have discovered one such system and this provides conclusive evidence for the existence of dark matter.
Fuck you, asshole.
To (inaccurately) quote some lines from "Yes, Minister":
Jim: Why do you need to know?
Secretary: I need to know to know whether I need to know.
Jim: Well, okay, what do you need to know?
Secratary: I need to know E V E R Y T H I N G!
Jim: Oh..
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
god is a who? Well which is it? I feel like I'm playing charades.
And who pray tell figured out that a god is a who?
Is he from "who'ville"?
And what's time got to do with anything?
Does anybody really know what time it is?
Does anybody really care?
If so I can't imagine why.
He may mean our interpretation is cartoonish, but it doesn't parse that way.
Lurking at the bottom of the gravity well, getting old
it's a fudge factor that the layman can understand (e.g. it's the opposite of matter).
With only 4% matter from TFA, could lead to the idea there must be a billion species & ecosystems we just can't detect, hence the thought...
man, we are truly stupid.
2.) If their deflection off course was caused by a misunderstanding of gravity, the periods of the planets would have been determined to be incorrect - and if that were the case, then New Horizons would have either missed Jupiter completely or gotten a tad too close...
Have you been touched by his noodly appendage?
Can someone please think of the poor helpless penguins on Pluto? And make sure those future dark matter tankers have 6001 hull layers.
Life is hilariously cruel.
\
I cant but help feeling like we applying classical science to something that is far more complex but let alone obvious at the same time. We now know black holes are at the centre all galaxies and I have oft wondered if the side effect of a black hole between the different planes of space and the matter contained within are in some way interacting as an effect on our plane of space. If this is true we will never find dark matter because we are looking at a side effect not some weird form of matter. Think of it as two spacetial planes and a black hole pulls these plains close together thus causing a wide spread interactive effect between the matter in each. So what we are seeing is a side effect not some goofy bit of matter.
and how would any of this be more preposterous than Dr. Mills theory?l
http://www.blacklightpower.com/theory/theory.shtm
Hmmm, dark energy - a Mars Bar made from dark chocolate... Yummm...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
IF such a particle is ever found, it would validate Supersymmetry. Most string theory models depend on Supersymmetry to be true, so a failure to find this particle (or ones in similar energy level) a whole generation of physics will need to be re-thought. As for dark energy, clear "blinking" sign WE ARE MISSING A BIG PIECE OF THE PUZZLE...
I remember reading a while back that scientists had done lab experiments in which they had particles of normal matter and dark matter in a vacuum. When the particles came in contact with each other they completely obliterated one another. That would surely say that dark matter in itself is quite real, and that it definitely has some form of energy to it. I suppose the question people would be seeking to answer then is just what kind of energy it contains, what effects it has, or what opportunities might arise from such a thing. As anyone can figure out, all energy could be harnessed in some way or another, so long as you could figure out how it would be done. As with every other theory out there, the 'dark energy' idea is a fantasy someone is coming up with to explain events they've seen. Not to say fantasies of this sort are automatically untrue, quite the contrary, people should keep in mind that many of these sorts of fantasies which people choose to adamantly deny get proven true later on. So who knows... maybe they'll be right, and 'dark energy' ideas will be proven, at which point someone will start coming up with ideas for possible uses and setting up tests and dark energy collectors and generators and blah blah blah, and then we'll all implode. :)
As far as the lab stuff I mentioned. I can't find a link to it right this second. I don't expect anyone to take my word on it, I'm just throwing it out there. I know I could very well be wrong because I haven't studied up on this stuff and I certainly don't know much about it. It just irks me that lately a lot of stuff I see people arguing against, as if they know for sure, is being proven true.
Well, that's exactly what our neighbors made of normal matter think about it. They have a mayority of the mass of the universe after all.
However, they can't see us either. The universe is a little like the silent hill movie.
We are Turing O-Machines. The Oracle is out there.
The colliding galaxies you are talking about is not really colliding galaxies, but colliding clusters of galaxies, this one is called the Bullet Cluster. A cluster of galaxies is a huge body of matter, which is not adequately explained by the only other competing postulate MOND. MOND requires some dark matter to exist for it to fit the cluster of galaxies, but it can do so currently by using hot and massive neutrinos, instead of unobserved weird dark matter particles.
But the real problem with using dark matter in either GR or MOND is that the dark matter should have a much smaller velocity than what is being observed, in the Bullet Cluster. Now the Dark Matter proponents are positing a new interaction that works only between dark matter. While MOND people are just scratching their heads not able to fit that aspect of the problem. You see that GR people have grown so accustomed to fudging factors by postulating new objects that they don't even stop to think that they are going in circles, just like the scientists in the age of Plato.
I do believe that there is light at the end of tunnel. Loop Quantum Gravity people are going in somewhat the right direction. The only failing being that they are trying to fit Relativity, which I don't believe is the correct one, it only arises in a small section of the universe where the curvature of the universe is not observable, eg our solar system. An offshoot of LQG is Doubly Special Relativity (ie there are two universal constants the Planck's constant and speed of light), which tries to include Planck's constant in Special Relativity, by deforming it. Now another guy has made a new theory by using Conformal symmetry to deform Special Relativity, this effort leads to CDSR which gives a natural explanation for the MOND phenomenology.
The interest in Conformal field theory of gravity is because the other three forces are a form of Quantized Conformal Field Theories. I am hoping that CDSR will make a connection with Conformal Gravity, at some level, and provide some insight into getting a sane Quantum Gravity Theory, which will incorporate both Quantum theory and Relativity.
The problem is that the Dark Matter seems to be moving at a much faster rate than expected. So now the Relativists are posing a new interaction that only works between Dark Matter ;-). They don't concede defeat easily, those Relativists.
In that case, maybe this next round of evidence will have to be not only beyond anything we know but also beyond anything we know how to know. "The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents." we're not even made of the same stuff as most of the rest of everything. "We're just a bit of pollution," (...)
"If you got rid of us, and all the stars and all the galaxies and all the planets and all the aliens and everybody, then the universe would be largely the same. We're completely irrelevant." "We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the deadly light into the peace and safety of a new dark age."
I lost my sig.
Dude, it's not Dr. Seuss.
This is a huge oversimplification that errs in favor of traditional cosmologies. The temperature, 2.7 Kelvin, was not "precisely" predicted. There were in fact numerous predictions. The accepted Big Bang prediction at the time was around 50 Kelvin and the steady state predictions were in fact far closer. If we modify history to our liking, then we impede our own ability to solve the problems we're working on.
This is a problematic assumption. We've discovered several supernova remnants that are bipolar symmetric (like 1987A). This was by no means expected to be left behind from a stellar explosion. Just using common sense, I would guess that the brightness of the supernova might even depend upon your perspective -- where you are located relative to the bipolar structure. To continue to hold onto your assumptions about supernovae behavior in spite of the fact that we've observed unexpected morphologies for supernova remnants is sloppy work. It wouldn't pass as science if we were talking about any domain other than astrophysics. In fact, this sort of reasoning seems to lend more credence to our stellar evolution theories than to our *observations*.
...
... people that are constantly attending conferences for domains foreign to
My take
One would get the sense from reading an article like this that all of the reasonable research options have been exhausted. But mainstream cosmologists do not consider it to be their burden to research alternative cosmologies. There are numerous excuses to avoid researching more down-to-Earth, physical explanations for dark matter and dark energy. Are they valid excuses? One can easily make a case that the existence of dark matter and dark energy infer a problem with our overall analysis. In fact, for every Slashdot article I see on the subject, I always see at least one reasonable person in this forum confident that these must be error terms.
And this is the *real* problem with astrophysics today: the unwillingness to question the assumptions that got us to this point. For instance, it's oftentimes argued that the CMB proves the Big Bang (etc etc etc). But it's rarely mentioned that we chose to believe that based upon some evidence, and that other evidence can be generated, if we desire, that supports alternative explanations for the CMB. If you ignore alternative explanations for the CMB, claim that it's existence proves the Big Bang, and then express wonder at the existence of dark matter and dark energy, then shouldn't you go back and take a look at those alternative explanations for the CMB? Shouldn't the anomalous data involving dark energy and dark matter cast doubt upon the conventional wisdom that got us to this point? If, like this article suggests, we're at the point of believing that dark energy may never be solved, then isn't it time to try to prove alternative cosmologies to the extent that we've funded this one?
The universe happens in all sciences at once. This is what makes it so complicated. Through the lens of any one particular science, we can formulate theories that explain it. But none of these theories will be correct because they all inevitably ignore our knowledge in all of the other domains. The only *real* way to understand the universe would at least theoretically be to understand and apply *all* sciences simultaneously. By this reasoning, one would somewhat expect that mainstream astrophysicists today are eager listeners
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
GR does not work at Galactic Levels, so there is no question of it working at the Cosmic levels.
r g%3Aastro-ph%2F0610298 (A New Force in the Dark Sector?)r g%3Aastro-ph%2F0609125 (Fits the Bullet Cluster with TeVeS, the MOND relativistic theory)
The real problem is MOND. If it did not exist then Dark Matter would be free to exist wherever it wanted. But with MOND the picture becomes more complex, now DM must fit MOND. It is quite easily provable that DM cannot fit MOND, just apply it to small cluster of stars at the outer edge of Milky Way which show Dark Matter. The problem is that for DM to fit Milky Way, it cannot be present in the Clusters. But some clusters do require DM. Now MOND fits both reasonably.
If you talk about Bullet Cluster, then don't because it proves that DM should have a new type of interaction because the DM itself is experiencing higher gravity than relativity predicts. Now this can be due to MOND. MOND can be fit to the Cluster by using hot and massive neutrinos. See the following papers.
http://www.citebase.org/abstract?id=oai%3AarXiv.o
http://www.citebase.org/abstract?id=oai%3AarXiv.o
The additional benefit is that MOND supplies the higher than gravity force required to fit the velocity of DM in Bullet Cluster.
Actually MOND makes it more easy for Dark Galaxies made up of hot and massive neutrinos to exist, because it makes gravity stronger. So yes, entire galaxies of hot and massive neutrinos are possible, and probably are present in most Clusters of galaxies. MOND shows that there is some matter missing from these Clusters. So the presence of Dark Matter is not fatal to MOND. The presence of Cold Dark Matter may be problematic, but still not fatal. The only thing that will be fatal to MOND will be if we find a body of mass that has more observable mass than it predicts.
It is not just a equation. It is a theory, which means that it contains a lot more features than a single equation. The equation is actually derived from the theory. The theory ie GR is very simple conceptually, that the speed of light is constant and mass curves the space it exists in. Everything follows from there. To change it will be very difficult. Now GR has 10 parameters of symmetry, we could go to higher symmetry eg 15, which is Conformal Symmetry and is observed for the other 3 forces. This will cause different equations of motion. Also Quantization will need to be done just like the other three forces. So what follows is a very complicated theory, which although in essence is very simply defined. We are probing this theory from multiple angles at the present time. Loop Quantum Gravity or LQG is doing it from the bottom, and Conformal Gravity is doing it from the large scale to small. They will meet sometime ;-). I am now of the opinion that the bottom up approach may have a higher chance of succeeding. Lookup Conformally Deformed Special Relativity or CDSR, which is an outgrowth of LQG.
Ah, the delusional people, then. Yes, I forgot to mention those. They're the ones who actually end up applying for the Randi foundation prize, while the true fraudsters just argue about why they won't bother.
Let's make one thing clear, since you mention psychology and the brain. In a sense you don't live in the outside world, not even in the world of your senses, but in the representation of it that reaches your upper consciousness level. When you see a car on the street, what your conscious brain sees isn't the raw stream of pixels from the eyes. There are several levels of buffering it, tokenizing it, pruning most of the information deemed irrelevant to the current focus of your attention (e.g., why you don't see the gorilla doing cartwheels in the background when you focus a car accident), indexing it, etc. The info you really operate on is the packed and processed result of that, not the raw data.
In a sense, at the conscious level you really operate sorta like on a MUD or old text mode adventure. What you "see" is more along the lines of a tokenized description of the information in the scene that's relevant to the focus of your attention. And you can shift that focus to go into more detail (losing more of the big picture) or less focused (losing details.) So you go, say, out of the house and see your brain gets the processed/indexed/tokenized version of, say,
"You are in your back yard. In front of you is your chicken coop. There are some chicken in it. One looks at you."
The funny thing is, sometimes these pre-processing stages malfunction and you get corrupted data at the end. E.g.,
"You are in your back yard. In front of you is your chicken coop. There are some DEVILS in it. One looks at you."
That's a true case that grandma loves to tell about. One of her neighbours at some point flipped to seeing birds as devils, and ended up in a mental hospital.
That's a simplified description of it, but it should give you a general idea. That's how delusions work. So just because someone is seeing some paranormal stuff, doesn't mean it's ESP, it can just mean that they're deffective in the head. Yes, to them it will look very real, and in fact to them it _is_ real. It doesn't make it "really real", so to speak. That's why we want some independent confirmation of some sort.
Additionally, there's one important thing there that throws a spanner in the works even when it is working right: the filtering stages. Most info in a scene is pruned basically based on what you want to see there. Committing it to memory involves even more filtering out, so basically you remember the parts _you_ want to remember. Well, the parts you deem important to see or remember, anyway. It's just a part of how the brain works, to keep the working set of data to a small size it can deal with. Otherwise it would get swamped in more data than you can deal with.
However it also produces the interesting effect called "selective confirmation." If it's important to you to notice that your pet theory is happening (e.g., that the phone rings more often when you're on the toilet), then you'll be more inclined to notice anything confirming it, and fail to notice or quickly forget anything that doesn't confirm it.
Additionally, even without a bias as such, you tend to notice more the things that are unusual or contrary to your expectations. You might not pay much attention to a dove, if there are plenty in your city, but you'd notice a gorilla or a parrot. You don't notice much when you hit in a RPG, because that's what you expect and take for granted, but you notice when you pull a string of 4 misses in a row.
Either way, some turns of events get noticed and remembered more than others, and that can royally screwed up the perceived probabilities of it all. Things which are really rare get perceived as happening to you all the time, while things which happen all the time are as good as filtered out. So it's damn easy to seem like you have some inexplicable or paranormal stuff at work t
A polar bear is a cartesian bear after a coordinate transform.
Step 6. Determine how much mass must be in the galaxy in order to provide the necessary centripetal acceleration to create the observed rotational speed using MOND, instead of GR.
Step 7. Compare answers from Step 4 and Step 6.
Step 8. Smack yourself in the head when you realize that there is no mass discrepancy. Then realize that GR is providing wrong answers to the questions posed by the Galaxies.
MOND is ignored by most of the scientific community although it has been giving good results since 25+ years. It has made testable predictions and all have been proved correct. There has been no failures reported so far, including Bullet Cluster, which poses bigger problems for Dark Matter (ie requiring a new interaction between DM) than MOND.
MOND predicts the break down of GR at galaxy scales. If GR does not work at the galactic scale then it is meaningless apply it at larger scales. DM may still survive, because MOND needs it at the scale of cluster of galaxies, but that doesn't mean that we will need Dark Energy. It may be that as Gravity becomes stronger at lower accelerations, it may become repulsive at cosmic scales. This is a preliminary result of Conformal Gravity. All other forces are explained quantified Conformal Field Theories, and it makes it highly probable that gravity is also explained by another Conformal Field theory.
One thing I presently do not get is where the energy leaked from red shifted photons go.
Every photon is quantized. It is a particle, emitted when an atom change from an excited to a less excited state (basically, an electron change from an outer to an inner position). This photon get different levels of energy depending on how far they jump, and different frequencies of light correspond to the photons in that light having a higher energy level.
Now, enter cosmology: The universe expands, so "hot" photons that are old have red-shifted ("cooled") to a very low temperature (about 4K, as far as I remember). This the background microwave radiation.
My question is: "Where has the energy gone?"
At a wave level, this isn't really a problem - there's just more waves going over more distance with the same energy. However, when we quantizise this, we should still have the same number of photons, with less energy per photon. So, where did the energy go?
Or - did I (and my aunt, who's a physics teacher and originally introduced me to the question) miss something semi-obvious?
Eivind.
Doubting the existence of evolution is like doubting the existence of China: It just shows that you're uninformed.
Humanity is just now realizing that we don't have a F****NG clue? Let's say collectively we know, what, .01% of what there is to know about absolute truth? Or anything at all, for that matter? An we tink we suuu smert!
Good to see ourselves humbled every once in a while. Don't get me wrong, we've made great strides as a race, but examples like this show us just how far we have yet to go, and also make us realize that in a universe of infinite possibilities, we've hardly touched the surface of what there is to discover. Most of what we do "know" we don't even fully understand yet! It's quite exciting to see breakthroughs like this... there's something very tantalizing about the unknown.
Dark matter is a mysterious attractive force operating on a scale of of hundreds of thousands of light years with about 24% of the universe's energy budget. Dark energy is a reulsive force operating a scale of billions of light years with 70% of universe's energy budget. Whether these are conventional particles, unknown particles, geometric effects, etc. it is not yet known.
majority of material of the Universe.Yet was never Observed on earth?
Its like having invisible elephants fly trough the buildings.
there is no leakage at all, the red shift is simply due to the doppler effect of the light source moving away from the observer. The stretching of the light wave is because the observer perceives the wave as longer, from its source perspective the photon hasn't changed at all.
I don't know much at all about this stuff (I'm only a few months from being 16) but it all seems really interesting. Just a thought here, maybe the "dark energy/matter" causes what we know as "gravity"? I mean at this point who's really to say, especially me, most of it is really over my head, but then again, who knows?
There is no such thing as dark matter and dark energy, it's called failed theory.
It's time to give up and create a new theory.
I know that my nerd credentials are going to be revoked for this, but I think the problem lies not in some exotic form of energy/matter, but in the equations used to derive there existence. We know that there is something wrong with either General Relativity or Quantum Mechanics because at the moment the two theories contradict each other. What if there is a fundamental principle of GR that is yet to be discovered? I think that Dark Matter/Energy is going to end up sitting next to Aether as a theory with insufficient understanding. DM/E has all the properties of a bogus theory: it is there to fix the observation to match theory, it has become increasingly non-detectable except by using the theory it is fixing, it is homogeneous and universal (why are there not lumps in dark matter). Having said this, looking for the stuff may well pin down enough observations to make a more fundamental solution clear.
JFMILLER
P.S. If you are not familiar with the discoveries of GR and QM or what was thought before their discoveries, the Wikipedia article is a good read.
Strive to make your client happy, not necessarly give them what they ask for
Why would anyone want to claim the Randi Foundation Prize? Don't you know what happens to the guy that did(will)?
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
When will physicists realise that adding patches upon fudges upon fixes is akin to adding epicycles to an Earth centric solar system and finally admit that some of their underlying asumptions must be in error. First there was a big bang, then the universe slowed its expansion for unknown reasons, then it speeded up, then it slowed again, now its speeding up exponentially. So they invent cosmological constants, then dark matter, then get rid of the cosmological constants, then add dark energy, then add back the cosmological costants again. Come on guys, start shaving that pig of a theory with Occam's razor.
If you have a problem with or disagree with their opinion, you should respond rather than abusing your mod points.
Jesus was a compassionate social conservative who called individuals to sin no more.
Dark matter is just another modern replacement for aether.
Jesus was a compassionate social conservative who called individuals to sin no more.
They're just making models and testing predictions, no-one is claiming we actually know for damn sure!
Darwin Hawking Blackmore