Our Universe and How It Works - with Jo Dunkley

Where did the universe come from and where is it going? Could our universe be one of many and how come the universe keeps expanding at an ever increasing rate?
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Most of us have heard of black holes and supernovas, galaxies and the Big Bang. But few of us understand more than the bare facts about the universe we call home. What is really out there? How did it all begin? Where are we going? Award-winning astrophysicist and Professor of Physics at Princeton University, Jo Dunkley traces the evolution of the Universe from the Big Bang fourteen billion years ago, past the birth of the Sun and our planets, to today and beyond. She explains cutting-edge debates about such perplexing phenomena as the accelerating expansion of the universe and the possibility that our universe is only one of many.
Watch the Q&A: • Q&A: Our Universe and ...
Jo Dunkley is a Professor of Physics and Astrophysical Sciences at Princeton University. Her research is in cosmology, studying the origins and evolution of the Universe. Her main projects are the Atacama Cosmology Telescope and the Simons Observatory. She also works on the Large Synoptic Survey Telescope.
This talk was filmed at the Ri on 23 January 2019.
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[@DouwedeJong]

It is hard to go back to basics for something you are an expert in and her excitement builds up as the story gets more complex. She loves this stuff and it make her gripping to listen to.

[@prabhakarhanchate6109]

Mesmerized

[@gerrytrevis]

She's very clear and methodical, I've seen a lot of these lectures and she might be the most clear.

[@dn1697]

.... clear to the point of unknowing ...

[@dn1697]

... universe expanding ? ... the confusion I'm finding is that galaxies simply moving further away, does that really mean the universe is expanding ? ... or simply because there is enough room for galaxies to move anyway ?? ... are we assuming the universe is spherical ?? ... it might be a completely different shape or no shape at all.

[@n1k32h]

Fitzgerald Scott Methodical. U like that yea? Well I’ll be calculative.

[@stevenzapiler5806]

There's no math (that I know of or have tried to imagine) to measure how Jo Dunkly's passion for cosmology affects those who learn from her. But my theory is that her passion and love for what she teaches is the most powerful force for knowledge in the universe.

[@Amazing_Mark]

Right on! She's brilliant. 👍

[@StereoSpace]

Very interesting, clear, and entertaining lecture. Thank you.

[@FirewaII33]

What a wonderful talk. Thank you to the R.I. and Dr Dunkley!

[@belwbarr]

A real picture of a galaxy far far away and a long time ago. So fun to watch your enthusiasm. Thank you.

[@gustavomoretto6449]

Brilliant. I've read and heard about these subjects many times and in this lecture, I at last was able to understand why, for instance, we see only one strip of our galaxy and not a more complex structure. I always thought we were just seeing one arm of it. Now I know we see "all of it" on a two dimensional flat line. Thank you for your teaching talent and your precious time.

[@elijaguy]

With such lecturers I am eager to learn science. Thank you for a lovely and very informative presentation!

[@BenKrisfield]

wow, just watching the beginning of this lecture, an explosion of ideas went off in my mind. Thanks.

[@visitor55555]

I absolutely adore the passion she has for this!

[@laomark9583]

Very good speech, Jo. Thanks!

[@charlieritchie5110]

Great talk, many thanks.

[@ottobhan725]

Jo Dunkley is an eloquent, balletic-moving speaker/educator of astounding clarity imparting knowledge. Kudos to RI and all its speakers of highest qualities... welcome Jo to top levels of teaching and knowledge exchange. Advobiscum Jo.

[@slackvariable7295]

just stop

[@zakirzak1494]

great presentation...Thank you so much

[@nigeldunkley2986]

From one Dunkley to another - excellent and clear explanations! Thank you so much Jo

[@ramajotwani8748]

Great presentation!

[@js3883]

Good talk.

[@fchimself]

very good lecture. thanks

[@0.618-0]

The very best presentation of the concept of Dark Matter and how it is evident around galaxies, aswell as the concept of the expansion of space.Thankyou Dr Dunkley.

[@unagondolaunremo]

thank you!

[@donaldskibo8970]

Excellent presentation

[@koblongata]

Wow I sat through the whole thing.

[@Ebenezer456]

I liked the explanation of the universe's expansion and the analogy of raisin bread. Helped me to understand it better. Thanks!

[@dawnhoward79]

Very enjoyable indeed 😁

[@nickacelvn]

Good stuff. I learned a lot. Thank you. E8 lattice?

[@amyers2141]

Thank you Professor Dunkley. Beautiful lecture, while politely pointing out the discoveries of Vera Rubin and Henrietta Leavitt.

[@basharatbala7617]

Great Lecture ..

[@kin0cho]

Jo is a great communicator!

[@carlpizzo9987]

I LOVVEEE THIS - we are all part of something greater than ourselves so no matter what you call it STOP arguing WE don't want to hear it anymore!

[@idio-syncrasy]

She worked very hard. Amazing presentation that tried to keep everyone on track.

[@Raphael_NYC]

Wonderful. Thank you.

[@DraconisWyrm]

This is the perfect background noise for space enthusiasts (everyone). Thank you, Star Scientist Who Imparts Wisdom.

[@AliHSyed]

I would be just as out of breath talking about our wonderful cosmos.

[@johnsheehan5109]

I'm sorry but why didn't someone get Professor Dunkley a glass of water? Marvelous lecture, Professor, thank you.

[@kenmarriott5772]

If our bodies can go all night long without eating and drinking, why is it necessary for people to be drinking from plastic bottles constantly now?

[@johnsheehan5109]

@@kenmarriott5772 I can see you've got a lot of experience with giving public lectures to large groups in lecture halls...

[@anthonymoon3747]

@@johnsheehan5109 Says a man talking from a bunker

[@taylorcervantes1995]

@@kenmarriott5772 I think it’s just because speaking for such an extended period of time dries the mouth/throat. Normally don’t need to sip constantly throughout the day but I have definitely gotten a dry/irritated throat when giving long winded presentations! I’ve noticed many presenters sipping water throughout for this reason!

[@billyplake6458]

I really enjoyed your lecture Jo! 💯

[@cryptolover103]

I totally enjoyed that.

[@tedhaluska9963]

Jo I think your presentation was well thought out and very informative. It was easy to relate to in the manner in how you explained the theory. as a laymen I found out things that peaked my interest ....and now because of your efforts I will continue to look at our cosmos in a new and exciting way...I commend you on your work... God bless

[@BaconbuttywithCheese]

Fantastic lecture. Thanks to the RI and Jo Dunkley for an entertaining hour of education.

[@alwaysdisputin9930]

I learnt from this ty.

[@visavou]

this is just amazing

[@Rescheff]

Finally Someone who Know how to explain... (beside her being a charming personality)!!!

[@Hotaudio40]

She is amazing!

[@petemchardy619]

Does she no about black holes

[@petemchardy619]

are alll back holes the same colour

[@eklim2034]

thanks

[@markjager8544]

Love the subtle dance..!

[@cosmoshfa88savant66]

Brilliant,,,,,

[@dunnel58]

Thanks Jo for that presentation.

[@OpenWorldRichard]

I really enjoyed this presentation which explains in a very clear way some very interesting history and highlights some of the main unexplained features of our universe. I particularly welcome the invitation from Jo to participate as an amateur in trying to find solutions to the question of dark matter and dark energy. I have been working on these problems for some time and I can see that the problem of not being able to identify the dark matter particle is that it is not a single particle but a group of two or more neutrons bonded together. This would be like an atomic nucleus with just neutrons so no electric charge and would only be apparent from its gravitational effect. The problem of dark energy is quite different. Firstly, you need to consider that there is a unique frame of reference in the universe which is called the CMB rest frame. We know this from observations of the Cosmic Microwave Background Radiation. The measurement of this CMB rest frame from the Milky Way shows that we are moving at a speed of 552 km/s within this rest frame and this movement is due to the expansion of space. This means that we can identify a particular point in space which I call the CMB rest point. Then the model of expansion of space is that all galaxies are moving away from the CMB rest point at a speed depending on the distance from the CMB rest point. We can think of the CMB rest point as the centre of the universe and Hubble's law tells us that we are located approximately 26 million light years from the centre. Now when it comes to interpreting the observations of distant galaxies, it is the distance of the galaxy from the CMB rest point which is important. The distant galaxies seem to be receding more slowly than we expected but this is not due to the expansion of the universe accelerating. Instead it is because our observation results of red shift versus distance are not linear. See also: www.academia.edu/5009126/The_evolution_of_the_universe Richard

[@nevermindmindn]

Neutrons bonded together as dark matter?? Dark matter is not normal matter... neutrons are normal matter...

[@OpenWorldRichard]

@@nevermindmindn Hello Vegie. The conclusion that dark matter is not normal matter has been made by looking at all of the individual particles in the standard model and showing that none of these individual particles could be dark matter. No-one has considered that it could be a bonded particle. Two neutrons bonded together would have all the properties of dark matter in that they would not react with photons and they would be evident from their gravitational effect. Richard

[@kevinlemon6537]

Her passion just bounces off the walls . Wonderful . Hard work for the camera man though .

[@christaylor8125]

Thanks Professor Dunkley. That was mind expanding. "Good Job" as our American cousins would say.

[@caseysaunders3016]

She “crushed it!”

[@midi510]

I find it surprising that she's only seen the Milky Way a few times. I've been looking at it all my life. I do live at 8,000' and hundreds of miles from the nearest city. I often camp at up to 13,000'. I grew up thinking that everyone saw it regularly.

[@arctic_haze]

I have not seen it for years. Namely since I stopped doing open ocean yachting and since the villages close to where we live all put up the orange streetlights.

[@megamcg4412]

She is really good.

[@jonahansen]

Very well done exposition! Kudos!

[@Dr10Jeeps]

An excellent lecture! Thank you Dr. Dunkley and the RI.

[@DV-dt9sq]

Such a beautiful presentation! I enjoyed sooooo much. It is so wonderful to see when someone loves the work they do. Bravo and thank you!

[@taleemikhidmat1579]

Good.

[@Rescheff]

She makes it so simple... SO SIMPLE...

[@marcelabassi6211]

Inspiring ... She is great. Dull audience

[@gerrytrevis]

Plus she mentions all these women who I never knew about which is pretty awesome.

[@Quark.Lepton]

With Jo Dunkley and Bo Diddley!

[@Midnight135791]

Very Good Lecture. It has me thinking somewhat differently on what I have learned already about Cosmology, Astronomy and Physics. Thank-You

[@openyoureyesandseethefutur4889]

great story telling , it use to be around a fireplace, now its photographed, recorded and shown on wifi

[@johnnym6700]

great story telling - filed under 'fiction'

[@anthonymoon3747]

Space comma

[@rafsh1846]

She is wonderful presenter, and gave high density of information with 0 mistake and I love how she trying to bring alife the women contribution to cosmology and astrophysics, across the history who always been covered and hidden by men .

[@nebexdoesnt8336]

Why is the picture provided from NASA 54:04 cropped at the top?

[@sIightIybored]

The cuttout at the top right? The Hubble telescope has 4 sensors, one of them has a smaller field of view, for some tradeoff I have forgotten.That is the notch.

[@bobbartola9496]

A weird hypothesis I have is that IF space (quantum space) is expanding at an exponential function (Tangent function), and if 0=infinite in quantum distances (allows for particle entanglement since 0= infinity in the quantum distance measurement). Eventually the universe's quantum space will "SNAP" and INSTEAD of a bounce it will be like a tangent function (go from infinite to - infinite (another big bang will occur).

[@LeeMcLaughlin]

I love her passion and enthusiasm for space. Love watching her presentation. Thank you for sharing. Cheers

[@ibrahimmohammad6128]

Thanks for this video, it's very important.

[@phoule76]

great talk, thank you! may I propose replacing our antiquated Imperial units with the peppercorn?

[@rickdees251]

The earth is not 100 times smaller than the Sun, like she said. That is just the diameter which can be misleading. It is more like 1,300,000 Earths will fit into one Sun.

[@rickdees251]

The earth is not 100 times smaller than the Sun, like she said. That is just the diameter which can be misleading. It is more like 1,300,000 Earths will fit into one Sun.

[@abathens]

@@rickdees251 Tell us about Disco Duck 🤣🤣

[@chipparker3950]

Really like her dress, especially the color . Or should I write colour. Enjoyed the presentation though it was pretty basic, must have been, I actually understood it, or think I did, most of it. Appreciated the candor re dark energy. "We call it dark energy because we don't know what it is. "

[@mollymoon3007]

Is the universe expanding, or are stars just getting further apart? As a kid i remember seeing the dots on a balloon analogy, showing how every point is getting further from every other point, but i noticed the dots got bigger too. I worried that all atoms were getting further apart, and atoms were also expanding. The distance to london getting bigger all the time, but cars and people got bigger too so no one noticed the change but if the speed of lights fixed then the universe would appear to get smaller ? then if speed is distance over time and all the distances were getting bigger light would stay the same speed but actually go fast as a meter is also expanding. i was quite confused :-)

[@TheVicar]

Same here. I'm confused but the way I try and imagine it is that everything is expanding but there is also local movement within a universe's boundary. If there is such a boundary My hands, the keyboard I'm typing on, the screen I'm looking at, the walls in this room and all from there to the shape of this universe's visible edge are all expanding equally. But there are local movements that we can easily see. The stars, solar systems, planets, planes, cars and ants can move closer (or further away) relative to each other Expansion is universal and invisible to the eye, because your eye, the object you can see and the photons of light are all also expanding equally. Movement within this expansion being merely directional and easily measurable, therefore causing my confusion? Help please! (8

[@danyael777]

21:46 What is the name of that supercluster? I can't understand what she says there.

[@tedhaluska9963]

I believe its Naniarchia

[@danyael777]

@@tedhaluska9963 thx

[@raycosmic9019]

If everything is moving away from everything, why is Andromeda moving toward us instead of away from us and other galaxies merging as well? Does the merging mean the the Universe expanded and is now contracting, or that the Universe is expanding and contracting simultaneously, expanding and contracting being a local phenomena?

[@minhtao9774]

I love you!

[@chrisparker2118]

"If you want to find the secrets of the universe, think in terms of energy, frequency, and vibration."

[@moelarrycurly708]

What is the speed of sight ?

[@raydodd8324]

She’s awesome. I love how she highlighted female astronomers. Are we to some small extent made of elements we actually created, here on earth, by nuclear explosions or other means?

[@blugreen99]

The Universe may be as great as they say but it wouldn't be missed if it didn't exist!

[@a-a-ronmayers8005]

Big Bang... LHC, if we lived on one of those newly created, now able to view because we smashed atoms together, everything would look huuuuuuuge distances away... keep going up levels and down levels... ;)

[@jamminwithjambo7729]

Jo!!! Wallzing....

[@Quantumoprh]

There are basic units in physics within the framework of the so-called SI system: • Meter (length): Defined since 1983 about the speed of the vacuum light

[@mellertid]

50:20 The "crisis is cosmology" was recognized at the time of the talk.

[@Kennymac8251]

Those 56 minutes flew by. Great video.

[@kevinhanley3023]

Hi. Before, when the universe was still opaque, there was helium?

[@tristancelayeta6890]

The 73% hydrogen and 25% helium abundances that exists throughout the universe today comes from the condensation period during the first three minutes. The 2% of nuclei more massive than helium present in the universe today were created later in stars. www2.lbl.gov/abc/wallchart/chapters/10/0.html

[@FakacX]

kzbin.info/www/bejne/l4G2pZ1oj9qLq8k -> primordial nucleosynthesis - 75% hydrogen / 24% Helium4 and some deutherium and helium3

[@MichaelFortner1989]

Helium nuclei would have existed from very early on (per the theory of big bang nucleosynthesis), but would not have formed true helium atoms until the universe cooled enough for the nuclei to capture electrons, which is exactly the time when the universe stopped being opaque, so called Recombination (they apparently named it before everyone agreed that nuclei and electrons had never combined before).

[@alvaug2]

Great talk. Thank you!

[@PRG888]

Jo really explains things well, even to someone as dumb as me :-)

[@DrINTJ]

It's a delight to watch. I envy those hearing about these things for the first time in such an engaging way.

[@jaykingston2171]

I often wonder if each super massive blackhole in the centre of each galaxy gave birth to all its planets and stars. The big bang sounds like the opposite end of a blackhole exploding in to existence projecting the whole universe. I also wonder if each galaxy is being projected by their black holes and whatever mechanism is creating the projection is on the other side of the black hole. I think it's possible that we live on a 2D plane but experience reality as 3D because we are trapped inside the projection. Maybe we don't see any new nebulae forming around the black holes because of the time it takes the light to reach the telescope!? It'd be amazing if each galaxy had its own physics and laws.

[@geoffreywilliams7705]

I think you should have made it clear that where we are here on this little planet of ours, is at the 'oldest' part of the Universe. ie we exist at the cutting edge of time. Furthermore, it is the same everywhere else in the Universe. But it is the 'slowness' of the speed of light that prevents any quicker form of communication. And consequently we see only the past wherever we look. If one does a mind experiment it is possible to understand this concept ; that the age of the Universe is the same everywhere. We are separated by time as much as by space. I think that you should tell everyone this fact . .

[@honeys.kapoor2838]

Any single thought or Universe works on the principle of force; through consciousness.

[@robinharwood5403]

If the concept of a spiritual force cannot have any effect on a material body. >>> Then you have to explain the things like emotions, Love/hatred., jealousy, envy and rationality. And If your body with all parts is just a random collection of chemicals that formed by chance over billions of years. >>> How on earth can you trust your own reasoning processes and mindful(unseen/ non-physical) thoughts that you think..???

[@eupraxis1]

It's 186,000 mps. Not a confusing number. Why round off to 200,000?

[@johnnym6700]

c=0

[@eupraxis1]

@William White Agreed, Saying "186,282 mps" isn't that hard either.

[@007atermis]

Still having problems with the idea that most galaxies are moving away from us when most of the galaxies are speeding towards the great attractor.....

[@damiankozowski2846]

The Great Attractor is simply a central gravitational anomaly inside Laniakea. Apparently Laniakea isn't even gravitationally bound thus it's superclusters will disperse over time. Plus the mentioned Attractor only speeds down the dispersion, it cannot overcome it.

[@marktime9235]

Details of planets 40 light years away, really?? And, could 'dark matter' be a result of galaxies distorting space/time, giving rise to gravity that appears to us as dark matter?

[@erfling1]

I really like her explanation of the appearance of the Milky Way.

[@placo10100]

Its not empty at all you just can't see more than a very small bit but intuitively most of us know there's so much more

[@graememudie7921]

Ok so planets are essentially invisible. So why is this not the dark matter we are looking for? There could be trillions of them and equal the mass that is missing. What am I missing here???

[@proximaakash2997]

Alpha centauri is the nearest star?

[@guitarboogieboogie]

Miles??

[@coldblaze100]

Dark matter as quantized inertia?

[@mrwideboy]

There are more theory's on cosmology than there are cosmologists

[@danielvazquez7482]

My curiosity is with galaxies 1, 2, 5 and so on of billions of years old that are measured backwards then suggesting they come from one spot or point. Moreover, if the universe is growing in all directions and from only what already exists then it seems to me there are forces beyond our universe that are pulling it apart. This would explain why we are observing acceleration. Btw billions of years old observations may well be useless.

[@robertcircleone]

If our so-called universe is part of something much larger, gravity from around our bit would tear our bit apart. So-called dark energy explained (maybe).