Dark Matter's Not Enough - with Andrew Pontzen

Andrew Pontzen on why the Universe should be weirder.
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The Universe seems to be governed by rules that we can, with some effort, understand. Andrew Pontzen introduces the stranger side of the cosmos - dark matter and dark energy - but then argues that these things are not so weird or unexpected after all. The strangest thing is that our rule-laden cosmos should be so predictable.
Andrew Pontzen is a lecturer and Royal Society University Research Fellow at University College London, as well as a musician and science communicator. His work focuses on galaxy formation and computational cosmology, as well as some early-Universe physics. Previously, he has held fellowships at Oxford Astrophysics and at the Kavli Institute for Cosmology in Cambridge. And now, he finds the time to go around the country presenting shows at science festivals.
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[@danchanner7887]

I think we have just found the next Dr Who.

[@dmcq7271]

Good one.

[@SuperPhunThyme9]

But he's not post-op.

[@RandomPlayIist]

@@SuperPhunThyme9 wtf does that mean?

[@allenmunich2816]

Or maybe he was the doctor he just didn't say timey wimmy or anything like that

[@dedesunbeam9361]

That's the funniest thing I've read in a long time!

[@Ilikeyourgirl]

He may not be a good comedian but he's a damn good teacher and knows exactly what he is doing. There was no point in time where I felt like the topic was boring or thought of something else and didn't listen. This is an amazing talk! Well done!

[@NLB90805]

He certainly has a knack for drawing in those people who have a deep knowledge of physical science. And those people who never stop learning. I really enjoyed this Lecture. I wish I had more Teacher's like him going through all the different years of schooling. Those who can make any subject fun and keep one 'Tuned' in is an absolute Gem of a purveyor of knowledge.

[@MrPDTaylor]

He's a great comedian.

[@phillynott2459]

Nah, he is a good comedian

[@Shafeeqh]

Interesting,, instructive añd informative. Thanks

[@nazosman984]

to all of you complaining about his humour, there are kids in the audience and they were engaged the whole time. Difficult to get kids attention these days. Brilliantly done.

[@Trucmuch]

I posted a comment about his humour, then read your comment and decided to delete mine.

[@WmTyndale]

Those are OXbridge Students not the kind that are amused easily by cartoons, sports and hollywood porno!

[@terryfuldsgaming7995]

@@WmTyndale are you deaf? There's clearly children in the audience... you can hear them constantly...

"these days"

[@phillynott2459]

"it's difficult to get kids attention these days"? What is your basis for this comment

[@Kugelschrei]

This is so cool, he must be an amazing teacher.

[@Sophiedorian0535]

“You can see why this is my favourite experiment: it’s pretty exciting.” What a teacher!

[@donaldhawkins7884]

have watched hundreads of lectures on physics, cosmolgy, found this to be one of the more intresting and understandble

[@MsGnor]

I wish I'd had a lecturer like Andrew Pontzen when I was at school :)

[@lesseirgpapers9245]

@@ralphclark The last 60 years they have been promising break throughs. Every time I look into these theories they fall apart under critical scrutiny. And they all tend to violate the principle that something and nothing cannot exist in the same time. If you look at it they are now consorting to fraud like the recent black hole pictures. These are not even close to the reality. The universe expanding at several times the speed of light? They are moving farther from physic and creating SciFI. These clowns are so warped in their head that the misinterpret every simple experiment. Take Prof Nimtz for example.

[@lesseirgpapers9245]

@@ralphclark Then show me respect. I know more than Suesskind. I would not blabber such nonsense. In Physic "to some extent it works" lacks any rigor of thinking. It is the words of a scam artist a snake oil drifter. Wake up man. America is not about being "tongue tied by authority" as per Shakespeare. In the last 70 years these clowns have been leading you in a Alicen wonderland using ridiculous terms with no meaning that results in absurd unverifiable predictions. Just a ;lone the recent pictures of the Black Holes was deeply dishonest.

[@kristofburek264]

Like physics, my school teacher was quite serious. But he also knew when to use humour and his eccentricity to entertain his class and bring clarity to a principle. Thanks! Mr Stevenson! you raised a lifelong student of physics! And also thanks! to Andrew Pontzen! Mush enjoyed!

[@garyrafiq9561]

​@@lesseirgpapers9245 Typical antiscience American who is mad at scientists for telling people things he doesn't believe in.

[@tonywells6990]

@@lesseirgpapers9245 Way derp.

[@leqin]

Well one thing is certain and it is that Andrew Pontzen's got to be one of the best science communicators I have ever had the pleasure to watch - well done Andrew - and if you watch this then also take a little more time to watch the question and answer session - I haven't seen so many young people so enthused about science before - awesome.

[@Quintinohthree]

He is a great entertainer as well. The humour he uses in this hourlong lecture is such that I'd gladly go to the RI over a nearby theater where for the same hour another man tries to entertain people with comedy alone. We definitely need more lectures like these.

[@apontzen]

Quintinohthree Nigel Oulton thank you both, such nice comments as this make the effort worthwhile!

[@jamiewaymire7599]

What a dynamic and fun speaker! Held my attention the entire time and that is hard to do! I enjoyed this immensely!

[@Necrikus]

Amazing that they could get the Doctor to give a talk.

[@beaconterraoneonline]

Who?

[@gamenerd4322]

exactly

[@andreasfinken2792]

Wow! I expected Rose to show up all the time :)

[@RafidMahbub]

He does have an uncanny resemblance to David Tennant.

[@BatteryExhausted]

I'm sure he can find the time.

[@seanjoseph8637]

A Great lecture on what we really don't know, I enjoyed it immensely and the lecturer is endearingly awkward and makes his points as clearly as is possible with such a "mysterious" subject.

[@GrigorisDeoudis]

"You must have chaos within you to give birth to a dancing star." - Friedrich Nietzsche

[@adithyaparupudi1336]

I thoroughly enjoyed every minute of explanation. It was made very simple to understand. That means he really knows his stuff. Very very interesting

[@jadecoley]

I'm a 50 year old kid and that was brilliant. Thank you so much

[@phillynott2459]

Me after 60 seconds: "worst lecture ever" Me after 10 minutes: "best lecture ever"

[@miglator1]

I dont understand how there can be so many people complaining about the jokes. I know most of you are physicists and are serious people and don't have any sense of humor but come on, this lecture was for kids and even if it was for adults what is the problem of making some jokes to make the lecture more dynamical. I am also a physicist and I definitely prefer that kind of lectures were the lecturer interacts with the audience rather than those boring ones were there is a person pretending to show the world that he is awsome and knows a lot of things without even minding if they are actually understanding what he is saying

[@metaparcel]

Dungeons and Dragons physicist more like it.

[@RoyFultun]

Bah humbug!

[@wellrose17]

miglator1 Coming from the layman's perspective I think he does a great job of articulating the importance of science & it's description as well. I haven't gotten in to the negative comments but those are just patterns I suppose. I like the the way he described our question & answer process. Remaining teachable is important. Perhaps we've passed this exam? Are we in need of a new teacher or different language? You understand what I mean? Perhaps it will never be fully understood. Or possibly a bit of creativity needs to be put in to our collective questions for a an extended period of time to rearrange our methods? I don't know. I'm an artist & musician who loves this stuff and likes learning. Cheers

[@Yatukih_001]

There is sufficient hard evidence that Dark Matter has been harnessed. It was harnessed in the past and used to power the world. Before everyone starts to attack me and each other over this amazing fact, facts are still facts.This is probably the first time I comment on the subject and it´s usefulness as an energy resource on youtube.

[@akizeta]

@@Yatukih_001 Facts are facts, except when they're just stories without any foundation in reality.

[@billsmith9711]

he has a very good delivery. I enjoyed listening and learning.

[@DavidFMayerPhD]

Either: "Dark Matter" exists in abundance, Or: Gravity at interstellar distances does NOT behave the way we think that it does. Perhaps, at interstellar distances, gravity is 6 times as strong as we believe it to be?

[@woahfarout8793]

Or we misunderstand inertia

[@ChilledfishStick]

It's not like the thought hasn't occurred to astrophysicists. Dark matter isn't something set in stone. If you work out a better model, you are more than welcome to submit your work to a reputable journal.

[@brainpain5260]

David, some physicists are working on modified gravity theories. If your implying we don't seem to be taking it serious enough......I agree. On the particle physics side of dark matter we have eliminated much of the possibilities and supersymmetry looks grim based on latest cern runs. I think we learned from the discoveries of QM that we can't rely on our intuition outside the realm of historical human experience. I hope to live to see the answer and possibly contribute to it's resolve.

[@mikemike6182]

Dark matter don't exist, we just don't fully understand gravity yet Yet scientists is so bold to say it exist Waste millions of dollars for detection but zero progress

[@karlamay_]

I enjoyed it so much that I didn't realize he spoke for 54 minutes. He delivers well and his jokes amazing! I feel like I understand but know nothing at all! I could listen to him all day and still not get bored. Most teachers should be like him, I mean, there are still wonderful teachers but most of them don't know how to teach and are only there for your grades. Lessons should be fun and interesting just like this, not boring reiteration of the books. Wish I could see him lecture in person. More power to you Professor!

[@fedeabascal]

Thanks so much for this lecture and the great Q&As

[@kathyyoung1774]

Humor is a wonderful teaching tool! Sorry some commenters prefer dry boring lectures. Most people appreciate humor.

[@leyawonder2306]

I found his jokes quite funny actually, am I alone here

[@FrederickTheGrt]

You're alone.

[@ksimvanderhlaar]

It was impossible to me to be distracted from this lecture. Andrew Pontzen is awesome at science communicating, information and humour were mixed in right proportions. Also, I didn't know there was chaos theory holding some place in dark matter problem, it really motivates to learn it more. And that long-exposure shot of the pendulum looked a lot like attractors in fractal graphic redactors. English isn't my first language so it's far from ideal but I'm trying to improve it.

[@GwennDana]

Conveying chaos science and Poincaré to kids in a public lecture. One cannot show enough appreciation for that.

[@chrissyphilp3619]

To be utterly non-scientific ... I love this man. Clarity of perception plus a sense of humour is a great mix

[@ParalysedGekko]

Then take a look at Sean Carroll's "The Big Picture" in this RI series. This is how comedy and science just add up perfectly. I wonder how that totally untalented Mr.Pontzen got access to such a fine panel of professionals that have been invited throughout all the lecture series. Calling that a "great mix": yeah, even if Donald J. Trump would give a lecture, there would surely be fans.

[@amoneyshredder9513]

I like sean carroll better

[@StephenPaulKing]

The vacuum energy has to be fantastically small for this explanation to work...

[@lajosbaranyi7333]

So well done! Amazing!

[@vishnuteja7522]

Has to be one of the best science talks of this century. Many people may not realize it but he touched upon some one the toughest challenges in computational sciences, statistical mechanics, chaos theory, vaccum energy(Casimir effect) in such an intuitive way. Like Einstein said " If you cannot explain something simply, you just don't understand it well enough" this guy knows his stuff well enough to criticize it well enough. Thanks!

[@richarddeese1991]

"What an eccentric performance!" ;) Thanks for a very interesting talk. Rikki Tikki.

[@horseman1968]

We are children running around with scissors ;)

[@susanhawkins5914]

🙏🙏👍 thanks for making a vague, mystifying subject (to me) just that little bit clearer. Terrific delivery - I was totally engaged throughout. And yes, the English accent and well versed, animated delivery made it all the more enjoyable. Back in my day during school physics lessons half of this subject matter wasn’t even a consideration!

[@bigcountry5520]

it would be difficult to say whether we can feel dark matter, or not, because we've always been subjected to it, so the true experiment would be to figure out how to block dark matter, and then ask that question.

[@paulg444]

He is solid gold !!

[@David-tp7sr]

When you improve your computer simulations of the Universe, how long before your simulation becomes so good that there are humans inside thinking they are real?

[@SEGODFREYJR]

I just felt my mind explode...

[@billymanilli]

will never happen...

[@MrPDTaylor]

2029

[@MaxBrix]

13.7 billion years ago.

[@moogfooger]

what a terrific lecture! Thank you so much. Cheers

[@skodbolle]

Great lecture, and humor helps you learn so much more :)

[@jojolafrite90]

Yep. Att 19:20. It's what I don't get. Everyone assumed it was made of particles instead of anything else, for example, it could be the influence of the mass of another space-time with it's own particles that don't directly interact with our normal mater (cf: dual universe theory). Or it could also be something else entirely. The point is that there ARE other possibilities to explain the excess of mass that we call dark matter than "Particles that weakly interact with other matter of our universe, but that are very massive too". I've never been a believer in those wimps... Some still try to find them with detectors (that are made of baryonic matter, of course, so they should hope the Wimp theory is the right one).

[@avid0g]

The point is that the dark matter does not clump into planetary sized objects, much less stars. It does not interact with itself or with our familiar matter, except through gravity. There is already an upper limit on how heavy a dm clump can be without already being detectable. The most sensible response to observations is that we need to extend the quantum theories to include "weakly interacting (no electric charge) particles with mass". Since we haven't needed dark matter to explain results from our "atom smashers", the energy (and therefore mass) of dark matter must exceed their energy capacity. This puts a lower boundary on their mass. Thus, "massive". Since _two_ galaxies have been found with *no* significant dark matter, alternate gravitation theories are invalidated.

[@jdavis417]

Douglas Adams was a super-genius! ;)

[@maxpandey]

An amazing topic brilliantly matched with the sparkling analysis of the mysterious universe ..

[@gunterstrubinsky9452]

I love it and so did the kids. You would never get them there, even less to listen to as complex matter as Mr. Pontzen talked about. Absolutely hilarious! Not to mention very brave of him to step out of science's comfort zone! (Ooops, I mentioned it)

[@jeremielebrun3637]

i'm french and i understand every words you say, that means your french accent is good enough EDIT: it seems that you were speaking english... i've probably no frenchin' idea of what you say... and your Baltimore accent is deplorable!

[@galbrunfranck9960]

Il parle anglais pas américain. C'est la langue que nous appren(i)ons à l'école.

[@jeremielebrun3637]

@@galbrunfranck9960 ... merde je croyais que c'était en français...

[@galbrunfranck9960]

@@jeremielebrun3637 Il y a des jours comme çà ou rien ne marche... un type drôle et intelligent et il est anglais... )

[@ChrisBrengel]

The emotional computer was pretty funny :)

[@terrymcnee3568]

A man who is such a good teacher for children is a brilliant teacher for us adults too Thanks

[@_FightForYourFreedom_]

Brilliant and entertaining too! Learned a few new things about dark matter that nothing that I had come across before had explained.

[@ToddSloanIAAN]

ENTHUSIASM, MAN!

[@colinsmith1495]

Or, alternative theory, maybe we don't have matter wrong (5/6ths of the universe not being what we think of as matter), but rather maybe we have gravity wrong. I mean, not *wrong* wrong, but like Newton had it 'wrong' in that when we got to planetary orbits and relativistic motion, he just wasn't quite right. Maybe Einstein and relativity are good for orbital mechanics and stellar motion, but not quite right on the galactic and intergalactic scale. There are a *bunch* of such theories, collectively called MoG (Modified Gravity) Theories, but none seem quite right either. So, basically, it's not really any more likely than dark matter, it's just that it's not really any _less_ likely, either.

[@JorgeConstancio]

i just love to know about how humanity stands in matters of science right now, thank you all by this :)

[@hamzariazuddin424]

briliant presentation...I was looking for something more technical but ended up watching the whole thing because of his style....clearly not just for kids but brilliant to see science taught in such a way...

[@JonnysGameChannel]

Is the arrow at 14:18 in the wrong direction ? Does anyone know ?

[@TheRoyalInstitution]

JonnysGameChannel Most (though not all) galaxies have spiral arms that trail behind the direction of the rotation. Andrew says that it does seem that he drew his arrow the other way around on this image of M81 but that the point he's making is unaffected. Good spot.

[@samuraiwarrior5]

+JonnysGameChannel Sadly, no prize for that find. But let's get back to the science at hand here lol great lecture.

[@JonnysGameChannel]

doceigen Heh, I thought you were trolling right away, but you made me google it. Nice try.

[@JonnysGameChannel]

7%=?

[@JonnysGameChannel]

doceigen So it would seem.

[@rizendell]

There is a fundamental problem with the whole dark matter bit and that is what we created it for (to explain 5x matter). Its suppose to cause and be influenced by gravity, but if it is just flying through everyone and everything and has no bearing on the orbit of the planets or anything else, then the science is wrong, the prediction is wrong.

[@LendallPitts]

+rizendell So much time and money are spent trying to save Einstein's theories -- to prove that he was right about everything. Saving Einstein means, among other things, saving locality, despite the fact that already in the 1960s John Bell demonstrated that Einstein (EPR) must be wrong about this. The reason why Einstein wanted so desperately to save locality was that "spooky action at a distance" implied that something was happening faster than the speed of light, and if that were the case, many of his theories would collapse. The trust about gravity is tied up with this somehow.

[@morkney8510]

+risendell How does it have no bearing on the orbits of planets? Dark matter, due to its gravitational attraction, is expected to condense and form large isothermal blobs. These big blobs will have their own gravitational pull, so they WILL influence the orbits of observable matter. I think your interpretation is wrong.

[@Yatukih_001]

Well you need a large tower to manipulate dark matter so you can harness it and then turn it into energy and use the electricity produced from that.

[@avid0g]

The point is not how dark matter (DM) affects planets, but how planets, asteroids, stars, and black holes affect DM. By repeatedly deflecting DM particles into Chaotic orbits around galaxies, and by capturing DM in black holes, condensed conventional matter has affected the dark matter by thoroughly randomizing the orbital paths of minute particles. On the other hand, with a diffuse cloud of dark matter passing through our Galaxy in a random spherical cloud with five times its mass and ranging far beyond the "edges" of our disc, the speed of rotation of the outer regions of the galaxy is increased. The fact that the spokes of galaxies are curved spirals and not a smear, as found around Saturn, is a testament to the profound long term effects of dark matter.

[@ZetaFalcon]

High brow humor without snobbery, simply wonderful!

[@chaptiss1]

I love this guy, I'm so glad I stumbled upon this video.

[@maxgalarza9955]

the dark energy of today is the old ether of the past

[@wirsindhelden0]

I was thinking about this the other day, and if anything I would relate the "ether" of the old days to the quantum field of electromagnetism of today. In many ways those scientists were absolutely on the right track and had the right notions.

[@1972martind28]

Electric Universe

[@JulianPatrickBronteGlenn]

@@dickhamilton3517 You're already plugged in: the trick is in unplugging.

[@MrPDTaylor]

...is the correct model.

[@melvinshelton8448]

Your KZbin blurb is spot-on in listing "science communicator" as one of your roles. You are definitely a star. In the sciences, it seems that you know something about a subject when you can simplify it without distortion, clearly enough that non-scientists can understand it, and remember it. You, like Sagan and Feynmann, have that gift. If I had had you, at some time, as my teacher in physics, I would have been seduced into studying cosmololgy. (At least, until my math gave out...) Thanks. I would like to see one of your professional presentations, but London is a long way from Seattle; I hope you have a lot of stuff on YT! M.D. Shelton, M.D., Ph.D. (Biophysical Sciences)

[@bijanajamlou5152]

Great presentation!

[@videom]

Dark Matter is as real as luminiferous aether was. We need to figure out gravity and throw dark matter behind us IMO.

[@kristofburek264]

Sure! I think he put across rather well that physicists from the future might well regard the concept of dark matter as laughably naïve. But he's amongst the best and I don't think I can do better right now.

[@econrith]

Especially black holes. Sag A

[@KipIngram]

I think that's a distinct possibility. There's no evidence for it EXCEPT our inability to make gravity work out right. So we just toss in some dark matter and say all is well. Well, MAYBE - but MAYBE NOT. We need to be more rigorous.

[@mikem.s.1183]

No. But definitely you have to figure out what our current understanding of gravity is before making such a statement. And comparing aether (no equations ever supported it) to dark matter (the mathematics point towards its existence) is illogical.

[@eddyr3691]

A thousand times more informative than any of the BBC Horizon episodes of the last decade.

[@tconthejazz1]

What a fabulous lecturer! Really good.

[@wailinburnin]

Comments on the presentation - seemed silly to some - but his delivery was totally chaotic, it was brilliant to his point. Bravo. Even ended with a jab at injustice with the economy bit (like a super clever anarchist, right there on Faraday’s desk!) subtlety indoctrinating your kids. Brilliant performance, guy’s a total genius!

[@demonslayer357]

25:10 "How on earth did you go about finding a millionth of a millionth of a millionth of a kilogram of something that's invisible and untoucheable?" LSD! Psychedelics!

[@0-m-1-n-0-u-5]

Something everyone should experience at least once.

[@Arktriam]

I'm only 20 minutes in so sorry if he explains this later on. Einstein says that gravity is actually space bending. So what if dark matter isn't matter at all. We think of matter as being related to gravity but what if the gravity we think is from dark matter is just space rippling in a fourth dimension from some disturbance like the Big Bang and not matter.

[@theprinceofdarkness4679]

Arktriam There might be something there. If you can find some equations to fit that and then find a way to test that, we will have a breakthrough in our understanding of dark matter. We are still working on neutrinos and testing all the parameters for that. Once that is done, we will need to look in new directions to find this elusive dark matter, whatever it really is. Unfortunately for us, the other dimensions are difficult to investigate because we have so many competing string theories. Quantum theory is very challenging already.

[@Arktriam]

Roger Smith I wish I could come up with equations and figure out ways to test it but I'm only a sophomore in high school. The most complex math I know is Algebra II and Trig. I can't wait until I get to college and have the resources and knowledge to pursue stuff like this on a deeper level. Until then, I can only focus on the fundamentals of these topics.

[@theprinceofdarkness4679]

Arktriam You are on the right path. Take Calculus as soon as they let you. Also take Physics. If your high school allows, take the courses at college or university. In the next 10 years, we are going to have some exciting times in Physics. You won't want to miss any of it and you will be in the right place. You will find those equations eventually. You are already asking the right questions.

[@kwanarchive]

Arktriam Don't be confused by the name "dark matter". It's just a placeholder name. Same with dark energy. They could just as well be called "Fred" and "Wilma". An exotic form of matter is just one of the more easily testable hypotheses we have, but it is by no means the only avenue of research. However, it must be said that post-Einstein theories of gravity, like MOND or elsewise, haven't had much success even from a mathematical standpoint.

[@johnkendal5562]

In other words untestable hypothesis - not empirical science - hence not yet proven to be true.

[@FalkFlak]

the example of modeling economics was an eye opener. You can have a solution/approximation without knowing whats actually going on. That was very humble. In contrast, when listening to other science presenters talking about dark matter and "stuff" you sometimes get the impression they want you to think they figured it all out.

[@EntropicNightmare]

19:45 While there is certainly a contribution from electromagnetic forces, the primary reason you don't pass through the floor is due to the pauli exclusion principle.

[@trajanaugustus2792]

I used to be enamored with British accents but people like this presenter make it annoying. The heavy breathing, over dramatic speaking, stupid jokes, etc just kills the pleasure of learning the subject.

[@romteb]

That's English (not british) people in a nutshell, always trying way too hard to be funny or charming, extraordinarily off putting.

[@passives0n]

He misses the obvious point that dark matter is likely massive blackholes with a constant ratio of 5:1 gravity to the visible mass in the universe. It may also be the property of the higgs field. As space expands the higgs field decreases in strength producing negative mass and gravity. I thought it was an interesting presentation.

[@meggido7863]

yeahh this is very possible that dark matter may be a brown dawrf white dwarf or even a black hole but i have seen some calculations that even this would not be enough to explain why stars travel so fast around the galaxy they say that there are no enough mass to create such gravity

[@Mernom]

Your explenation about the higgs field is actualy counters your point, since the higgs field losing strength would require even MORE stuff to make up for the 5/1 ratio. It having more effect on the galactic scale could explain it though.

[@aurelienyonrac]

I like how you think. i was just thinking about negative mass and gravity. and a way to test it. if scientist can test there theory on economy why not do that with negative mass and negative gravity? Let us see how it apply in every day life. 33:59 "massless particle only travel at the speed of light" . All particles travel at the speed of light and are 2 dimensional plus time. When they are slowed down below the speed of light they develop mass, when accelerated above the speed of light they develop anti mass. Pretty funny. Let us see that applyed. "Everyone is doing the best they can and if they could do better they would" that is the speed of light. Now if you congratulat someone they will have a tendency to have better self esteem, more presence, more mass. People are attracted to them, they have gravity. But if you push someone who is allready at it's max you get negative gravity, they push you away, in exactly the opposite of what you want. Just as predicted by Herman Bondi in "Review of modern physics". Funny and true. inspiered by "the concept of mass" by Jim Baggot

[@avid0g]

The recent discovery of two galaxies with little or no DM has refuted the alternate gravity theories. Watch for corroboration of more light weight galaxies.

[@Age_of_Apocalypse]

Andrew Pontzen: Brilliant! Thank You!

[@danievdw]

Very interesting talk, and well presented.

[@RonJohn63]

17:15 Novices trust experts on a pretty regular basis, no?

[@luke666808g]

+RonJohn63 On average, comments like that are likely to be a pun, or perhaps you just need a stronger computer to calculate just how regular a basis it is.

[@martinzitter4551]

+RonJohn63 - I was a professional pert for many years. I retired and now I'm an expert.

[@alexbowman7582]

It would be more accurate to call it dark knowledge.

[@vladtepes7539]

n cold n basically not to make out.

[@ryanfitzalan8634]

i really thought this was about what Dark Matter is, only to get to the end and feel very duped

[@chestypants78]

The part around 45:00 re: economics 'dragulescu and yakovenko 2001' was fascinating. Great lecture.

[@Will-be-free]

It used to be that scientists made up formulas that would fit what they could observe. Lately it seems that they instead comes up with make-belief stuff to explain why they don't want to change the formulas with new observations.

[@Doniazade]

The mic is too close to the mouth again, lots small irritating noises from breathing etc. Not as bad as some previous videos but it would be nice if you could capture cleaner audio for more pleasant listening.

[@nightrous3026]

and the lisp. (im sorry)

[@rgibbs421]

Couldn't have said it better.

[@dredrotten]

Why! Why! Why! Do they have to have this forensic type of audio on so many videos? It turns me off and I cant watch them!

[@therocinante3443]

They need to hire a better audio engineer!

[@therocinante3443]

Red Rooster, What is "Forensic audio?" Did you just make that up?

[@ellaa123]

great lecture, thanks

[@Na-eo1gx]

This guys an amazing presenter!

[@edek3159]

I feel like I have asthma from his breathing

[@terryfuldsgaming7995]

I feel like i have cancer from your comment...

[@roxannamason4400]

Dark matter is the spirit world, unseeable in our existence.

[@cdurkinz]

I've actually thought of this as well. Definitely makes you wonder....

[@theundead1600]

Maybe but maybe not for long.

[@traditionalsunni629]

6:40 you are in for a treat. Damn he didnt lie. That was soooo goooood

[@youtubemusic374]

he is a veryy talented speaker and he really can get the attention of the young people in his audience with ecellent ideas and in the end he showed an absolutely brilliant computer simulation how galaxies in the early universe merge and how they are pulled together by their dark matter. All these facts were presented with a profound knowledge of didactics and great and fantastic sense of humour that caught the young people by their heart. This wa s one of the best and smartest talks that i ever heard on dark matter Joerg J.

[@ricardf1857]

INSANE CRINGE MOMENT AT 24:18

[@verneukteaap]

I watched the entire video and while I'm not an expert at all, on anything physics related, I feel like it was a bad presentation. And I don't mean the jokes as ofcourse I understand a large part of the audience were children, but inherently. After about 50 minutes I really hoped he'd end with some sort of eye-opening revelation, or a conclusion that would blow my mind, but what he pretty much ended with was: "We can only give you predictions of things we don't understand. Estimates so broad and vague that they encompass nearly the entire subject so that eventually, when precise evidence does come up, we can say that we weren't wrong." If this really is the only point he made, then the one hour talk was a bit disappointing. However, a lot of the comments here seem really positive about it. So am I missing something? English isn't my first language so if there is something I might not have understood correctly someone please tell me. Thanks a lot.

[@edkorthof]

I think that's the state of the science wrt to dark matter and dark energy -- they produce good simulations/models, but at the same time are somewhat unsatisfying (for many people) as explanations. I actually really liked the analogy provided by the "physicist's model of economics" -- the way physicists use dark matter and dark energy might turn out to be very accurate, or it might be wildly different from the actual mechanics but still produce similar predictions on aggregate.

[@leobritton8929]

To point out, chaos is a question of systematic understanding, he pointed out that it is difficult to be precise about the start conditions of any given system. His point was more despite this lack of available initial field conditions that we can infer that dark matter field and dark energy fields both exist.

[@brett22bt]

You could tell he really was excited about that pendulum experiment by his deep breathing.

[@davidwaynechoate8059]

There's gonna be like 100 or more "Dark" add-onns to the Big Bang Model..It's just insulting now.

[@lito11111940]

I agree, it's utterly absurd !

[@Yatukih_001]

Exactly. And everyone is acting as if everything has already been discovered.

[@rgaleny]

What about ELECTROMAGNETISM? dust BUNNY GALAXIES.

[@NLB90805]

I just want to know where do all the odd number socks, that go missing, after one has put them in the wash - then dryer. And blamo, where did the matching sock to my Argyll pair disappear to, some other dimension or universe? Floating-off into some yet unidentified "Odd (Man-Out) Sock" Field, where all these socks disappear to? Another one of those heavy, heavy questions science has yet to discover!

[@david203]

Patterns are indeed important, but the specifics are even more important. That is why 100 years from now physics and daily life will be different due to genuine breakthroughs in understanding. And that final question, whose answer was omitted, is very interesting indeed, since neutrinos are passing through the Earth and us right now in great quantities, and they do act like dark matter.

[@TheLovelivepeace]

Very captivating

[@carlhopkinson]

Isn't the fact that there exists a Andrew Pontzen enough to qualify the universe as weird enough??

[@iasnaia-poliana]

Beginning with laughing at Poincaré is not really presenting oneself as wise. But it brings joy to the children doesn't it?

[@simonpmccullagh6320]

Lefonkismine I think this is from the Christmas lecture series and it's always for kids, it's annoying as an adult but we're not the target audience, ho hum.

[@iasnaia-poliana]

Simon P McCullagh Thank you for the clarification, I didn't get that point actually.

[@_brett_7893]

Lefonkismine And I suppose having a pretentious-looking profile picture on Google+ does?

[@EvelynDayless]

Lefonkismine I thought it was more laughing with him.

[@iasnaia-poliana]

***** Queer as folk Fritz, your only one!

[@julianbassk]

Great lecture. Sometimes with the kid-geared RI lectures, it doesnt hold my interest. But this weaved together dark matter, chaos theory, and even economics in ways i never expected. Kudos! Also i thought it was pretty hilarious

[@happyhugs]

Brilliant ! Thank you ! :))

[@goliathsteinbeisser3547]

*Dark Matter is not enough* Jeez, you physicists are needy.

[@theawantikamishra]

Hahaha :D I guess we are

[@sugarfrosted2005]

29:30 Remember kids, floats aren't real numbers.

[@vgrof2315]

Thank you.

[@madden1957]

Brilliance and entertaining. This guy is a rare one. Good Job Andrew!

[@banmadabon]

Ok mom, nice try...

[@madden1957]

@@banmadabon Whaaaaaat????????

[@banmadabon]

@@madden1957 Given that I've found the bloke's humour terrible (I'm not the only one...) and the super flattering comment of yours I was jokingly implying that the author was his mom in disguise...

[@madden1957]

@@banmadabon You think HIS humor is bad yet you need to actually EXPLAIN yours??? Such irony.

[@FrederickTheGrt]

Banmadabon's comment was the only thing I actually laughed at. The video was cringe.

[@AboveMediocrity2010]

Sleep the electro magnetic force is even more significant then you think. In fact the electro magnetic force is the single most important force in the universe. Search up electric universe and Wal thornhill

[@parkjammer]

This guy proves that comedy is not an amateur sport and is best left to professionals.

[@kblocal07]

parkjammer he is a scientist doing a lecture for youtube. be a bit boring if he didnt have any character wouldnt it. jokes werent very good but he was likeable and knowledgeable. also, kids seemed to like his jokes.

[@istvansipos9940]

he gives this lecture to children. it worx just fine. perfectly, actually

[@therocinante3443]

Imagine a comic trying to explain (let alone understand) the things he talked about? Do you watch stand up and feel the need to criticize them on their understanding of physics? Think about things before you say them, lol.

[@aditimisra80]

parkjammer thats prolly because comedy is not a sport at all.

[@okimotus]

Surely, you can do better

[@johnmcclain3887]

A couple things, regarding the pendulum, first off, an "led" is a coherent light source, meaning you lose substantial light when it's even slightly off axis with the camera, leading to the "dead zone" on the right. The second thing is the fact we are dealing with a "pendulum situation" as "control" so we must see back and forth movement based on the length and mass ratio, controlling the harmonic frequency, meaning every movement must move through the middle, to get to the other side, so right from the start, it's in the middle twice as much as either side, but in fact, equal time, on average, to both sides added up, that would be the equivalent means of looking for common patterns, in the sides, basically, folding down the middle, vertically. I suspect there would be a similar pattern density in the two sides, put together, to that in the center. I'm not sure, but trying to consider the issues mechanical in its movements.

[@royrasmussen9738]

Thank you