William Unruh - The view from GR

[@cosmogallaro4609]

Unruh is a badass

[@tjock-tv5181]

I love hearing Unruh talk on physics. I wish there was more on the internet. I would absolutely love to hear more.

[@coastwalker101]

Anyone who loves a good detective story cannot fail to be intrigued by the convolutions of the discussions on understanding black holes. This exposition is a classic.

[@Taqu3]

This room is heavy. Great talk. Great points. Thanks for sharing.

[@isedairi]

I like how Unruh makes fun of the U.S. western coast physicists: min 46:45: "in this crowd telling stories with no support is the way its done"

[@isonlynameleft]

I like it when Lenny messes with people 😆

[@ynvch]

Is that Leonard Susskind at the right, in the front row?

[@vinm300]

I'm pretty sure that is Susskind, yes.

[@vinm300]

In fact those 3 on the front right look to be Preskill, Susskind and Maldecena.

[@jimjackson4256]

Jonathan Carreño good observation

[@HyperFocusMarshmallow]

Scott Aaronson is on the front left btw.

[@isonlynameleft]

Why is Scott Aaronson ,front left, rocking himself back-and-forth so much 1:15:00 😆 I love physicists there's such quarky people 😄

[@non-inertialobserver946]

Legend

[@vanikaghajanyan7760]

Expansion is a special kind of motion, and it seems that the Universe is a non-inertial frame of reference that performs variably accelerated motion (according to general estimates, this acceleration is: a=πcH).* Real gravitational fields are variable in space and time, and, developing GR**, we can now talk about the fact of the possibility of generating gravitational field in a non-inertial frame of reference (a=g).. That is, finally achieve global (instead of local in GR) compliance with the equivalence principle. Then the energy density of the relic radiation, that is, the evolving primary gravitational-inertial field (= space-time): J= g^2/8πG ~1500 quanta /cm ^3, which is in order of magnitude consistent with the observational-measured data (about 500 quanta/cm ^3). By the way, it turns out that the universe is 1.6 trillion years old! P.S. You can also use the Unruh formula, but with the addition of the coefficient q, which determines the number of phase transitions of the evolving system: q=√n', where n'=L/8πr(pl), L=c/H. Thus, T*(relic)=[q]ħa/2πkc (=0,4K), which is in order of magnitude consistent with the observational-measured data: T(relic)/T*(relic)=2,7/0,4=6,7. {However, it seems that the presence of a factor 1/2π in the Unruh formula is not entirely physical.} --------------------- *) - w(relic)^2=πw(pl)H, a=r(pl)w(relic)^2 =g=πcH, intra-metagalactic gravitational potential: |ф0|=πGmpl/λrelic , m(pl)w(pl)=8πM(Universe)H; { w(relic)^2=πw(pl)H. **) - See "GR was QG".

[@vanikaghajanyan7760]

GR was QG: docs.google.com/document/d/1FyD9vlFkQmVuVHWXNJSuuk6T86aJqqFG/edit?usp=drivesdk&ouid=110286572639581187540&rtpof=true&sd=true

[@NothingMaster]

If you happen to be almost as round as you are tall, the black hole could spaghettify you into shape. Finally a practical use for a black hole.

[@Vazhaspa]

Apparently the cameraman has gone to sleep and has ruined the whole picture!!

[@TheMemesofDestruction]

52:56. -- Thank you so much! ^.^

[@TheMemesofDestruction]

1:10:07 -- Destroying Unitarity.

[@TheMemesofDestruction]

0:20 -- Black Holes Form

[@TheMemesofDestruction]

3:05 -- It doesn't know what's goin on locally.

[@TheMemesofDestruction]

1:13:30 -- Professor Susskind. ^.^

[@TheMemesofDestruction]

57:58 -- Singularity not a singularity?

[@neiljohnson7914]

I didn't understand a word he said, but Santa Claus sure knows his physics

[@MudahnyaFizik]

Where's lenny? That was funny

[@slapitman]

this rules

[@-_Nuke_-]

If only we could talk about other aspects of reality (for example politics) in this manner... Where people really *want* to discover some deeper underlying truth, other than basing their personal truths on inherent hate and prejudice and misunderstandings... That's why you should study Physics and Mathematics if you want to find a place of sanity and completely loose sanity by studying sociology (for example)...

[@renephilipsen6381]

Black hole core contains trapped '0 Kelvin' (read dark matter). A fusion with 0 Kelvin is impossible. Matter spins around this core with zero resistance. Dark energy arises between core (Dark Matter 0 Kelvin) and horizon (Matter >0 Kelvin). Dark energy is a neutral player between 0 Kelvin (dark matter) and >0 Kelvin (matter), energy is born. A black hole contains enclosed space (dark energy 0 Kelvin) in its core, it feeds on matter (everything >0 Kelvin), matter that revolves around the core in a free spin. The horizon persists as long as it is fed with >0 Kelvin and is bound to TIME. TIME has enclosed SPACE here or holds SPACE (dark matter '0 Kelvin') TIME. SPACE and TIME together in a black hole. At a safe distance far outside the black hole, the ungraspable 0 Kelvin forms the carrier of our universe (so-called dark matter), matter (>0 Kelvin) condenses into structures that form the visible universe in TIME supported by 0 Kelvin that creates SPACE. By-products are 'dark energy and energy'. Our sun for example or a grain of sand here on Earth is a concentrate of heat numbers deposited within the carrier SPACE (0 Kelvin) and it is a matter of TIME that it decays into 'dark matter'. We live in SPACETIME without knowing that it is a dance between 0 Kelvin and >0 Kelvin. We live in grace of warmth and zero heat. Thanks!

[@realcygnus]

superb content !.......its quite interesting how many of the listeners couldn't accept that some of their beliefs could be so easily squashed...... Deny, reject & even ridicule contrary evidence.....& these are the "smart" humans.

[@armchairintrepid9575]

black holes are not black holes. they are donuts. donut shaped.

[@lchpdmq]

Interesting guy, good vid. But not a good teacher lol