Dark Matter - Sixty Symbols
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- Опубликовано: 5 апр 2010
- We take a look at mysterious dark matter - and a chocolate pie.
Featuring Meghan Gray, Ed Copeland and Mike Merrifield.
More videos with Dr Gray: bit.ly/Meghan_Playlist
It's an embarrassing fact that only relatively recently, we discovered that 95% of the universe is missing. Dark Energy makes up about 70% of the universe, but here we are concerned with Dark Matter which makes up about 27% of the universe. Put another way there is about 5 times as much dark matter as there is regular matter. Unfortunately we can't see it, although we are searching for it. So here we look at why we think it exists and what it might be? Featuring a chocolate pie!
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Very clever to have that pie on hand. Otherwise we would never have grasped this so-called "three-fourths" concept.
James Butler Yes, and it was dark, too.
But I got a bit confused, when they said, that it´s actually transparent, because in my eyes it sure still looked brown & delicious:)
All the best,
Forrest Gump:)
LOL
5:15
When it comes to chocolate pie, "The heart has its reasons of which reason knows nothing." 😂
Part of that pie represented itself o_O
Well played, Sir.
Winter Summers about an atom's worth
It's a recursive pie.
Right. Every set is a subset of itself.
@@leonhardeuler9839 ye
I want that pie.
xXEliteTNCXx i just want a slice q_q
+xXEliteTNCXx The cake is a lie!
Klaus Von Liechtenstein Still waiting for the "Why not both"-Guy
xXEliteTNCXx ^^ im a compromise guy
Klaus Von Liechtenstein me too actually ^^
Had a smoke before this and all I could think about was the pie
Paul McDonagh weird flex but ok
Astronomers have thought of that, but even if you add up all black holes, cold gas, brown dwarfs, etc, it just doesn't give you enough mass to account for dark matter.
just eat that pie already
That Pie is very distracting.
Makes me...Hungry
even me
Does dark matter have a dark periodic table?
Umang Bhat We'll know only the day we get to understand it.
Heck, it might even be not a single thing, but rather several other "realms" as incapable of interacting among them other than through gravity as we are towards them.
Nice concept
Umang Bhat It could be. Dark Matter is not really the best name since that implies we know it is matter, when in reality we don’t know.
It depends on if it interacts with the strong force. If it doesn't, then the particles can't bind to each other to form more complex structures.
But even if it does, it shouldn't influence the properties of the composite particles much, since what decides the properties of the element is the outermost electron layer, which they would not have, since they don't interact with the electromagnetic force and can't have a charge.
Actually, if they don't have a charge, does that mean that there would be no factor that prevents from more and more dark matter to clump together? Since there's no positive charge to push protons apart...
Never thought a video of dark matter could make me hungry. Seriously the first three minutes i only heard pie, pie and pie.
Id like to see an update of this video where we get to see the ten years of progress from then until now.
Wow everyone is so young! Just came across these channels recently, and wish I had found them earlier! Love everything you do!
wow this completely blows my mind, please keep us posted on this subject and also bring us up to speed with dark energy story, Thanks, David.
Where is it? Its dark you can't see it.... lol
...sounds so Monty Python the way he said it XD
My astrophysics professor always said that dark matter: "is a real bitch" lol
I love all of these guys, and they're all incredibly humble and intelligent people, but let's all take a minute to appreciate Brady Haran - not only for making these videos in the first place, but because though he remains behind the camera and out of the spotlight he proves himself to be as smart as any of the rest of them because he fearlessly and consistently asks the right questions. Thank you Brady, and all of the rest of you at Sixty Symbols/Numberphile. Keep up the wonderful work!!
Thank you for all those wonderfull video's. I'm a teacher on high school in the Netherlands, so this is far from my daily work. But I love how it trains my brain.
I started to get interested in these kind of video's, when I say a documentary on the Fermat theorem a few years ago. Now I ended up here.
Sorry for my poor English. It is not my native language.
This video made me hungry. I'll tell you what. Since you're not using the dark energy, why don't I...dispose of it for you.
If it is gravitationally interacting with itself as well as normal matter, why isn't dark matter "lumpier" than is apparently observed? Normal matter is very lumpy. And as it apparently has mass, and there's about six times more of it than normal matter, why hasn't dark matter formed "dark black holes"? Or has it?
thank you brady and thank you the professors, this is fascinating :-)
"What would happen if I drove my car into a big clump of dark matter?"
This is what makes your videos relatable!
i was just talking with a young lady teenager and she asked me what i was watching i showed here the screen grab of dr gray(i think thats her name?) i told her she was a cosmologist ,and she said ohhh she works with makeup.....priceless
.......wow
gotama420 congrats. great education you got there
MsHoaxx how do you mean?
***** danke schon
***** I swear this really happened i almost lost it ,
the schools are ok here but there are a lot of hill people who are not real big on education. I was lucky both my parents instilled a will to learn on us.
Umm...that piece of dark matter looks delicious...
Great video! I must admit the moniker "dark" matter made me think of something like soot, but you make it clear that it difficult to detect - "elusive"!
"They seek it here, they seek it there..." Pimpernelium?
Brady, I would love to see a video on the interaction between dark matter and black holes. It's tricky to find good information on Google because to so many people they're just interchangeable "mysterious stuff I don't understand" so hearing the scientists' perspectives would be really awesome!
Where can I find the recipe for dark matter chocolate pie? Or there is no way of knowing it? :)
I love all of the Brady channels....absolutely fascinating.
I'm not an astronomer, astronomy is for me just a hobby, but it makes me think of all these posibilities, and these videos help me understand all sort of things, and the real scientists that do the explainig part, they do it in a way that is easy for everyone to understand it all. So, thank you, Sixty Simbols :)
Nice video! One question though, does dark matter also has wave like nature?
Dr, Gray is absolutely endearing!
So, basically, we're still stuck with an aether.
searching the 'Extra footage' link, can't find it, great video :D
She really does have an impeccable speaking voice. I love listening to her explain things.
I love the quote from time stamp 10:11 to 10:23.
I see the Crips have started to diversify their activities.
lol chea its what ya gotta do to put da bread in ya bois hand. - of course im refering to street molecular science. these streets are hard for a young physicist.
Bilb Ono My favorite rapper is Young Phyzy. Well either him or Higgz Tha Boson
Hey I love what you guys do y'all should make a video on pulsars and or magnetar
Thank you for your explanation
Are your sure the dark matter isn't a combination of quarks that is neutral like 2 strange and 1 charm?
Brady or someone from the Sixty Symbols team: I love your videos! I'm a high school science teacher in an American international school in China and you guys do a great job of making things visual and accessible for my students!
Some of my students had really good questions about dark matter (very proud of them), and I was stumped!
Does dark matter interact with black holes? Black holes collect mass around them because of their tremendously strong gravitational fields, so shouldn't we also see black holes becoming more massive several times faster than we can account for by monitoring their intake of "normal" matter?
8 years later and I still think about that pie.
I loled so hard when she places the cake on the table after she cut it.
I thought the first slice was a third of the pie, but what do I know?
The biggest problem I have with the dark matter theory:
Why doesn't the dark matter affect planetary systems? If there is dark matter permeating space all throughout a galaxy - enough to pull stars around at high velocities - why is it not affecting planetary orbits *at all*?
Why can we completely explain the orbits of the planets with conventional theories? We only needed this idea of dark matter after observing the orbital motion of stars. Well after we had explained the orbits of the planets quite accurately. Why does dark matter seemingly only affect the orbits of stars?
Perhaps this is explained within the theory, but I've never heard this question even asked.
It does. Like people are gravitationally attracted to ants. It is bending the light of distant galaxy's. It is operating on a different scale.
Vinthis1 Yes, I am aware that its most visible on large scales. What I mean is, can we see its influence on planets at all? What do the equations say the influence on planetary orbits should be, and could we measure that?
The effect, if dark matter is fundamentally affecting galaxy structure, is surely not going to be immeasurably small. It might not be overwhelming but we should surely still be able to see it.
Personally, it feels more like we need to work on our theory of gravity. Obviously work on both theories is required, but I have a hunch that it is gravity behaving differently rather than dark matter.
***** This was actually proposed in the late eighties by A scientist named Milgrom. He proposed what he called Modified Newtonian Dynamics, which suggested that at low accelerations the force of gravitation begins go by 1/distance rather than 1/(distance)^2.
This would work to explain the motions of stars in galaxies without the need for dark matter halos, but doesn't explain the heavy gravitational lensing of the galaxy clusters seen in the video (among other things). Dark matter is a much more complete theory which is why it's preferred.
Drainojunkie Yes, I am aware that Dark matter is a fuller theory, but my question is, can we see its effects on planetary orbits?
If it is permeating all of space and dragging stars into large orbits, shouldn't we be able to measure its influence on planets as well?
I am not saying that I think this ruins the theory, I am just wondering if and how the theory deals with this, as I have never heard anyone mention it.
From what I understand, as far as we are from the galactic edge, we wouldn't see any effects on the orbit of planets because we are far enough from the halo that the gravitation would likely be affecting the orbitals too uniformly to measure.
However, I second your question. I would think that very close to the halo we should see that orbits elongate towards the edge of the galaxy as they rotate. I'm just not sure that we can measure that, or if the effects on out own solar system would be large enough to measure.
Essentially, I just spent all that time to say "good point, I don't know".
I liked the unsophisticated thumbnail of the chocolate pie!
The simplicity was in such contrast to the matter at hand... (any pun that could be derived from this was not intended).
thanks for showing us that super computer, very cool!
Am I the only one who thinks that woman is breath takingly gorgeous?
Nope. Not the only one.
She's super sexy. Love me some science girls.
She's clever. She's beautiful. She's perfect.
Nope
Andrew Trigueros she's attractive
I NEED THAT PIE! It looks.... NECESSARY!
What makes me not repeating it repeatedly is the guaranty that I will repeat it as a whole!
I wish I were smart. So much of this stuff I can grasp at a conceptual level, but it eludes me. Especially the idea of general relativity. How time moves slower in other time frames, like a rocket speeding by is something I will never fully grasp. Like this dark matter thing. I just have to assume it to be true and move along with my life.
the Kripps have a computing centre to simulate full universes of dark matter? wat..
What was the rest of the pie?
John Kerley Dark energy.
John Kerley Deez Nuts
Joshua Lemire hahahthat's funny xddd
This lady is super nice and an excellent speaker as well.
I _really_ like chocolate pie. Great overview and update of dark matter.
That pie.
Dark matter is assumed to exist because our theories brake down when trying to explain how galaxies stay together without it. Could it not be that our theories are just wrong?
ajuk1 There is no theory on why galaxies behave the way they do. The math changes for every hypotheses.
ajuk1 Yes. This is a valid question.
Modified Newtonian Dynamics is a theory that accounts for the galaxy rotation curves by modifying laws of physics at larger scales.
+xokocodo Modified Newtonian Dynamics also requires dark matter to work. ;)
That is always an option. But because our theories give the right predictions in so many other areas it is more likely that there is a mysterious dark matter that we haven't accounted for, rather than that there is a completely alternative explanation for everything out there.
But believe me, there's thousands of incredibly smart people trying to come up with alternative explanations!
We didn't know that light traveled at finite speeds until someone observed the eclipses of the moons of Jupiter very carefully and saw discrepancies with what Newton's theory of gravity predicted. Having confidence on theories that have repeatedly proven themselves true allow you to postulate the existence of otherwise unknown entities to explain anomalies in our observations.
Is it possible that dark matter can form a black hole? And can we distinguish one from "regular matter" black hole?
GOD DAMN!!! I come onto RUclips to help me forget my chocolate cravings and run into this video!
Mmmmm... dark choc.. ehum.. matter :-)
Blood's better step it up. The Crips already got super computers.
CanadianBoardCrew came to the comments immediately to see if someone else got that, lol well played
Jocelyn Robyn no one here about that life
Not really related to quantum gravity tmk, but that sounds kind of like the competitor theory to dark matter: Modified Newtownian Dynamics (MOND) which introduces slight changes to the equations that only have an effect on larger scales. Brady, it'd be awesome if you made a video about that. Maybe you can find someone who is not in the Dark Matter camp? (: (I vaguely remember Prof. Merrifield mentioning someone next door working on it...(?))
Did you use what you learned doing the vuvuzela video with Prof. Moriarty to enhance Megan's voice in this clip?
Physicists: The is no aether!
Years later...
Um, there is dark matter and dark energy, and...
Sixty Symbols What if dark matter is a particle with absolute zero temperature? It does not react with other particles nor emit light because it cannot, but it still has gravity. You should measure dark matter at your laser cooler experiment.
^(Do I get a Nobels prize for this idea)
You might if someone does the experiment and mentions your idea,else no
Nothing can be at absolute zero. If we had the exact opposite of a Nobel Prize, you might have earned it. Also, instead of getting a million dollars with the prize, you'd be fined a million dollars as a penalty for believing that you can pull ideas out of your rear end and win cash and valuable prizes.
The "Vacuum Energy" effect of stiffness or hysteresis has an equivalent in water, in that warm moving water is "softer" and more yielding than cool still water, and the same applies to the atmosphere, ..and thixotropic fluids of any type and scale are a property of synchronization, which blends in with mass, gravity, momentum and large "objects" astronomically (?), inertially-gravitationally bound or "congealed". (Like chocolate pudding)
Though I can absolutely recommend the Corsair (and/or CoolIT) product lines. Running a i7 3700K@4500mhz workstation here & it's a dead quiet system running the H100. Very nice. :)
We don't know if dark matter really exist, we only know that galaxies are rotating much faster than their mass should allow.
There are many other clues that Dark Matter must exist.
The CMB power spectrum, galaxy cluster masses, galaxy cluster interactions etc. etc.
Thøger Emil Rivera-Thorsen ...Gravitational Lensing
I found some dark matter in my toilet earlier... xD
you should see a doctor
You didn't get the joke, pal.
I feel that DM is leftover aftereffects of comprehensive dynamics placed on past conventional matter as humans understand it.The most difficult part in understanding it, is how DM's interreational status compares with standard matter as we know it.I feel that expressively this would be categorized as base weights measurements based in a comparative quantitative survey.
A recent paper (2017Nov) claims that "scale invariance of empty space" might have the same effect as dark matter/energy. There are also ideas about Modified Newtonian Dynamics (MoND) which is another alternative to dark matter
Nobody can see that dark matter, nor can detect, measure, prove, affect, etc. But at that the physicists know for sure and tell exactly how much space it occupies and gravity it has. How can one assert something about anything if one knows nothing about it at all? I wonder if the physicists ever were struck by the thought that their knowledge of the universe is near the absolute zero.
They have proved it through equations
Because we don't "know nothing about it at all". We know it interacts gravitationally. We can see and measure this affect. We can calculate how much of it is needed to cause the effects we observe. And the answer is, a lot.
Smart attractive female physicist/astronomer with chocolate pie talking about... er... I got a bit distracted 😥
+Silence is Golden Duct Tape is Silver That's a smutty interpretation. BTW Duct tape comes in black and silver 😜
Same
8 years later I am still looking at the pie.
14 years later and i still think about the pie
Thank you for your enlightening words. I have been working in physics for over a decade now without knowing that dark matter only interacts weakly. Really appreciate it.
why are they presenting this as a 'fact'?
Because it is an observable, measurable fact.
ek_tha_KC I don't think you understand. We can measure a gravitational anomaly, and we have named it's cause "dark matter" as a placeholder. It exists. Whatever theory you are talking about, it should account for this measurement.
Vinthis1 By its very definition, you can't observe dark matter. It's inferred, not observed. I don't think you understand it very well.
legisnuntius The gravitational effects are observed. The cause of the effects is inferred. If any theory is going to be accurate, it is going to include these effects, regardless of what explanation it has for them. The physicists in the video presented the effects of dark matter as fact, because they are. None of them provided an explanation for the effects as fact: 4:24 and again at 7:24.
Vinthis1 so you are saying effects are a fact right?? not the dark matter...dark matter is just a proposal and a possible reason for the effects. We still do not know whether there is really any thing like that.
Love this girl....unlike emancipated american whores she does not need to shout or take an aggressive stance to prove a point and garner attention. She is just smart and cute.
Have you done a video on Dark energy Brady?
The possibilities are endless. And its irony that prevails in these kind of cases. Everybody is looking up while they might be next to us..lol.
Do we see any evidence of these ratios changing in anyways? I have a hypothesis, but mind you I'm not in this field, so I don't know. It's that while the universe expands it also becomes increasingly more complex and so there will always be room for evolution of the mind.
If was lumpy enough you might even listen for it with microphone. Due to the variation in pull on the material of the device. Maybe it is like oatmeal porridge.
In one version Membrane theory, dark matter is just gravity wells from normal matter in a nearby universe. I equate it to having each universe on a sheet of paper and drawing on them with a ball-point pen. The drawing in the paper is matter, and the indentations are the gravity wells. When you lay one "universe" page on top of the other and then draw "matter" onto the top one, you can see the "gravity well" indentation on the bottom page(our own universe). It makes sense to me.
I could listen to Dr Gray all day.
Cool stuff, good brain food.Dark matter sounds like skimming stones over water at the beach, but you can't see the stone. Each time it hits the water we see the ripples but never the stone. Cool.
From what I understand, some/most Data Centers use a hybrid water-A/C cooling unit for their servers (basically a refrigeration unit cooling the water that's used to cool the air...i believe). But supercomputers are so advanced and different in such ways, I wouldn't have a clue to what would be best...like hot water?
Professor Merrifield, is it possible for galaxies to form without dark matter, and are there any examples of galaxies that have rotational speeds suggesting there is no extra, unseen matter in that galaxy?
That's a smart question!
just curious, how do the closed captioning captions get generated? On half the videos, like this one, they look to be automated speech-to-text captions -- when the profs speak quickly or hit particularly accented words, the captions make no grammatical sense. But in other videos they look like someone was typing off a script -- the captions always make sense, but they frequently don't match the audio (reorganized sentences, omitted words, etc.)
You are right. They try to autogenerate them unless someone provides a manually typed transcript :)
I agree. Love Corsair. I'm testing an H80i on this i3 3225 atm for my Moms build and it keeps the temps under 55C, even oc'd to 3554MHz at 1.2v (from 3300MHz at 1.1v), without fans even! As long as the room temp stays under 35C at least, otherwise it'll get to 58-59C. But I'm talkin an i3 after all.
great video .
I clerly see the error in computer simulation shown after 9:42. It assumes that matter lumps only at certain regions, but not inertia of the already formed smaller lumps running into bigger lumps of matter. So, there is no rotation, and it doesn't looks like real galaxies or something similar.
Each smaller lumps of matter may interact each other, forming 'twisted' looking structures, which is common in nature if you look how clouds are formed (although different forces, including Coriolis forces acting upon molecules of air and water vapor).
Also, during lumping and 'running' of the smaller lumps toward bigger center of mass, matter experiencing something resembling air drag, because matter in front of moving lumps of matter is not yet 'swept', so every next lump has greater velocity - because previous lump of matter sweeping this area (creating less resistance).
If so, then there may be explanation why galaxies' arms moving faster than expected, also why doppler shift between galaxies looks like universe expands, or like dark energy pushes them appart.
On this animation, look carefuly - it appear that 'new space' emerges in between lumps of matter, while whole picture looks stationary - nothing expands.
I know this seems silly to ask, but does "dark matter" have anything to do with the "evil" side of things? Or in the bigger picture evil is just a relative concept, just a property of everything, like the negative side of things to counter-balance with the positive side of things, to keep equilibrium, like in magnetism and electricity? Does gravity also have a negative gravity? Does negative gravity exist? Isn't centrifugal force the escape from gravity, being it negative gravity? Is the centrifugal force of the arms of our galaxy pushing our planet outside, or are we being pulled in? If we are being pulled in, won't we end up all crunched in the center?
The energy potential of that pie is so large, that I can smell the chocolate even trough my screen!
@sschhuu the other GUY with the glasses did that too when explaining a quark
Now I got your point! I don´t know how they would make it and I don´t know if we can observe a black hole growing in size ( Which would be the counter proof). It remains an interesting question....
Having just watched 6 Dimensions, Extra Dimensions, and Dark Matter back-to-back, it seems an obvious suggestion that the anomalies we see in gravity distribution would be caused by something going on outside of our 4 observable time-space dimensions. Perhaps a video to explain how this compares to the hunt for exotic "dark matter" particles?
So it does react with itself? I've heard otherwise, but oft wondered how it could "clump" together.
Brady, we need an update on this video! The LHC might be able to elucidate the identity of Dark Matter and I'd like to hear the profs talk about it.
I've a few suggestions what dark matter and dark energy are and i bet that people are already thinking about this: 1. broken gravity or free gravitons in spacetime. 2. particles too small to detect 3. psi phenomena emitted by nonliving and living things 4. spirit realm that exists in another dimension (i know people are smirking at this but options are still options)-ghosts sometimes interact with electromagnetism but are mostly not present in our universe.
@Nyphur I understand you view in that you want proof. I however regard this as a public forum for thought and discussion. I did try to work on the geometry and if you search for "The Effects of an Index of Refraction for Dark Matter.xlsx" perhaps it will show up. You can take it or leave it.
This Chanel is awesome
@Nyphur I agree with what you are saying and when Doppler red shift fails to explain NGC7603 I think you at least have to start to question it. I'm too lazy to give you mathematical proof and perhaps it's beyond my capabilities. Also with only 500 characters at my disposal it's hard to give a meaningful explanation. But there are several ways of testing this, but I don't have a telescope or a way to measure "red shift". Do you?
Now, there is a better explanation to the rotation of the galexies other then dark matter. When matter reaches near speed of light speeds it won't be able to get faster. Now matter further away could have the same velocity as the matter closer due to the atomic speed limit. Right?
Since dark matter only seems to interact through gravity with bosonic matter, how does it fare near or inside black holes? According to the ratios discussed, dark holes should contain 5 times as much dark matter vs. regular. I never hear dark matter discussed in conjunction with black holes.