Structures in the Universe

How did the cosmos transition into space characterised by galaxies in a plethora of different shapes of great beauty?
This lecture will consider what happens when groups of galaxies interact with one another and what happens when these galaxies collide and merge.
A lecture by Katherine Blundell OBE
Gresham College has offered free public lectures for over 400 years, thanks to the generosity of our supporters. There are currently over 2,500 lectures free to access. We believe that everyone should have the opportunity to learn from some of the greatest minds. To support Gresham's mission, please consider making a donation: gresham.ac.uk/support/
Website: gresham.ac.uk
Twitter: / greshamcollege
Facebook: / greshamcollege
Instagram: / greshamcollege

[@fazilnajeeb9097]

Remarkable Lecture to the Public!! She is very enthusiastic and passionate about it. Very communiticative indeed.

[@ArtDocHound]

Thank you, professor. Have a great day.

[@alancrabb]

Speech is correctly synchronised after 3 mins - stick with it! "Katherine Mary Blundell OBE is a Professor of Astrophysics at the University of Oxford" and is married to "Stephen John Blundell (born 1967)[1] ...a professor of physics at the University of Oxford." [Wikipedia]. Imagine the conversation over tea and toast.

[@jkaryskycoo]

Thank you for teaching us about science.

[@robertblackwell1350]

“Vastly in excess of human timescales” must be classic British understatement for “melt your eyeballs and boil your brain kind of big numbers”. Also, the simulation of the fly-by is just beautiful.

[@climbeverest]

Dr the world is richer because of people like you

[@kenchesnut4425]

Such a wonderful communicator...MUCH LUV FROM N.AUGUSTA S.C

[@bobd5119]

What an excellent presentation! It is huge fun contemplating big things.

[@jamesdolan4042]

"It is huge fun contemplating big things". Is that a pun? "The Unicerse went from smooth to structured or lumpy". Is that entropy? Excellent presentation, thank you.

[@edysinsimon8646]

I've found your lectures quite satisfying whilst I lay in bed waiting for the slumber to arrive upon my eyes. I feel like when I'm falling asleep I still seem to be focused on your words. That's when the real magic happens! I wake up the next morn and sometimes thru out the day I find myself thinking about things I've heard...somewhere? Again, Thank you for the subliminal lectures?

[@Tom_Quixote]

What do you "lay" in bed? Eggs?

[@bovegan4710]

Marvellous! Thank you very much indeed!

[@teashea1]

very excellent content and style. articulate and intelligent.

[@shaunlanighan813]

Excellent lecture with beautiful photographs.

[@monicaaparecidaoliveira8063]

Excellent lecture. Thank you.

[@climbeverest]

This is incredible for us to know the sky

[@MOS6582]

Great talk.

[@Mrch33ky]

Great presentation. Though I must confess, I remain skeptical of the CMB maps and what they can tell us.

[@matthewkelly2399]

Nice one

[@janibeg3247]

excellent

[@vernonvouga5869]

I love this lecture and I love the fact that the people watching this have already known these things for years

[@charlesmadisonrhea]

Do gravitational waves affect the spherical perturbation of the blast wave? The increased gravity associated w the star clusters.

[@earthexpanded]

33:45 "If only we could observe galaxies evolving on the timescales on which they actually evolve, it would be a wonderful thing; but of course, we can't." This is going to be a round-about comment, but I assure it pertains to the above statement and explaining how we can in fact see precisely this. Since the observation of increasing redshift per distance in all observed distant galaxies in all directions, we have interpreted it to be caused by motion which is then interpreted to be caused by expansion of space. However, gravity can also cause redshift. And importantly, if light from all distant galaxies were to be gravitationally lensed into a Figure-8 orbit flow pattern by a sufficiently massive object--such as the Great Attractor--where all the galaxies we see at sufficiently large distances have the light traveling in a Figure-8 orbit where it literally passes *through* the object it orbits, then arriving at Earth from any angle due to bending light and additive *gravitational* redshift from the orbit flow away from the central object. Light traveling in this manner would be redshifted per distance (overall) by gravity. Thus, nearby galaxies are real while more distant galaxies are actually "optical illusions" or more precisely snapshots of galaxies at earlier stages in their evolutionary process. Therefore, if we can fine-tune the exact details of the above process, we could determine which galaxies are the same and then have many images of the same galaxy across time. We could even see the Milky Way galaxy in its past and from the outside. Sure, it requires throwing away a lot of our interpretations of observations. But, that doesn't make it not so. After all, it not only provides a mechanism for redshift per distance without adding new mechanics, only using previous, but it further simplifies previous by showing how magnetic fields are caused by gravity (that there is evidence for a Figure-8 orbit beyond just the actual magnetic field structure).

[@LuciFeric137]

How did supermassive black holes form so early?

[@vernonvouga5869]

Well if we know passing through the barrier of a void could possibly cause a mass extinction, it would both constructive and interesting... if we had a conversation about this right now! Do the properties of space change once we pass into regular space?

[@vernonvouga5869]

Like seriously once we pass through the barrier on the other side of the bubble , and if everyone survived the high-energy event... would Jupiter gain more mass?

[@john_critchley]

Can someone please provide me a reference to the Hunga Tonga-Hunga Haʻapai eruption pressure wave being detected in Gloucestershire?

[@42Goatee]

...why are we still thinking of super massive black holes at the centers of galaxies and galaxies as two different things?..

[@CLipka2373]

Audio is a bit out of sync at the beginning.

[@MsHburnett]

Remember genesis

[@AG-of3ix]

You state theories as tacts. Why is that?

[@BarefootBill]

We don't know how stars form. Makes me froth at the mouth when so called astrophysicists say "We Know". Just makes me want to call you a liar. Plain and Simple.

[@TheStruck3r]

She talks about this stuff like grownups speak to kids. In reality, she knows nothing about it. Its all sparkly, rotating, beauty arms, glittery, amazingly smoothly distribution blablabla. Gas compression... Get outta here.

[@gabrieldunn7384]

​@@TheStruck3r You post like a child.

[@shadetreader]

Great lecture, but please stop humouring climate change deniers.