Avery Broderick on a black hole breakthrough from the EHT

On May 12, 2022, the global Event Horizon Telescope (EHT) collaboration unveiled the landmark first image of the black hole at the heart of our own Milky Way galaxy, called Sagittarius A* (or Sgr A*). On this special episode of Conversations at the Perimeter, Lauren and Colin talk with EHT scientist Avery Broderick, who leads the EHT Initiative at Perimeter Institute, about the significance of this discovery. He explains how the EHT collaboration created an “Earth-sized telescope” – a network of eight radio telescopes on five continents, all focussed on a single spot on the night sky: the heart of the Milky Way, 27,000 light-years from Earth. Broderick holds the Delaney Family John Archibald Wheeler Chair at Perimeter, and is an associate faculty member jointly appointed to Perimeter and the University of Waterloo. He also leads the EHT Initiative at Perimeter Institute, which is one of the 13 partner organizations in the EHT. Although his childhood dream of voyaging through the universe on the Starship Enterprise remains out of reach, Broderick says hunting black holes (or "fire donuts," as he playfully calls them) is the next-best thing.

Conversations at the Perimeter is co-hosted by quantum physicist and lecturer Lauren Hayward and journalist-turned-science communicator Colin Hunter. In each episode, they chat with a guest scientist about their research, their motivations, the challenges they encounter, and the drive that keeps them searching for answers.

[nicholasperry]

For a guy that can't concentrate for more than about 5 minutes this has been a pleasure to watch. Excellent communication from a guy who really knows his stuff and how to communicate it. Thank You Avery and the presenters for letting you explain.

[snowkracker]

Crazy to think that humans have built everything using elements creating billions of years ago in the nuclear furnace of stars that went supernova and now using those elements to piece together telescopes to understand how the universe works. We quite literally owe everything to stars. Even our bodies are made of elements that were once created inside of stars.

[ray]

Humans are amazing 🤩 organism. The knowledge we have gained will hopefully prevent our extinction. Earth 🌍 is rare / special.

[mounorman]

*My Thoughts*
I'm not a theorist or an astrophysicist but I always knew inside me that the entirety of the galaxies in the universe are formed and held by the driving force and effects of those Black "holes" in the center, that is at least for me the theory, so hearing him say that the SMBH in our galactic center only affects its surrounding area was really odd ...it's like observing a whirlpool in your bathtub or a tornado .
Why all the spiral arms are moving and pulled like a whirlpool if not held in place by our galactic center ?
What is the relation of our Sun to our solar system i feel is Sagittarius A to the MilkyWay galaxy .

[nkh]

This is the exact conversation I expected after the sag a star pic

[markusmaximus]

Comment on Andromeda's black hole, it's fairly close and we have a good view to it, can it be seen?

[markusmaximus]

Are block holes shredding heavier elements back into more simple particles and atoms in their plasma jets, effectively recycling new nuclear fuel for new stars? It seems that gravitational waves near the black hole could provide the energy to do this.

[markusmaximus]

It seems to me that is a smaller solar black hole fell into a larger black hole and event horizons touched, that something extraordinary would happen like a massive ejection event.

[garymaxwellian]

How'bout telescopes working in tandem in Earth orbit and in Mars orbit? When approaching opposite sides of the sun, that makes a huge radius telescope..😁

[EKDupre]

How wild is it that we're living through this? Wow. I wish Albert Einstein could see this.

[markusmaximus]

Did the existing telescopes have to be modified to process 1mm waves?

[thelyrebird]

I'm wondering if they can extend the size of the earth sized by using the earth's orbit..

[jeffclarkofclarklesparkle]

I wish they had shared the hundreds of pictures that made up the final image as well. They look much clearer than the fuzzy final picture, no?

[nmarbletoe]

35:15 those bubbles... why are they above and below the plane when the bh is pointing approximately with the plane?

[markusmaximus]

Is it possible to discern differences in red shift of the near horizon photons as the orbit the BH, one side towards us the other away?

[PsilocybinMagic]

Maybe the real black holes are the friends we made along the way 🖤

[shawns]

For some reason people dont know that Einstein repeatedly said that singularities are not possible. Wherever you have an astronomical quantity of mass "dilation" (sometimes called gamma or y) will occur. Mass that is dilated is smeared through spacetime relative to an outside observer. General relativity does not predict singularities when you factor in dilation. Einstein wrote about this in the 1939 journal "Annals of Mathematics". Nobody believed in black holes when he was alive for this reason.
There is no place in the universe where mass is more concentrated than at the center of a galaxy. 99.8% of the mass in our solar system is in the sun. 99.9% of the mass of an atom is in the nucleus. If these norms are true for galaxies than we can infer that there is 100's of trillions of solar masses at the center of high mass galaxies. There is no way to know through observation, there is far too much interference, dilation and gravitational lensing. High mass means high momentum. If we attribute a radius to these numbers we can calculate that relativistic velocities exist in these regions for the same reason we could calculate the surface velocity of the sun if you doubled the mass but kept the same radius. If you look at a common relativity graph you see velocity on the horizontal line and dilation on the vertical, even mass that exists at 75% light speed is partially dilated.
The mass at the center of our own galaxy is dilated. In some sublime way that mass is all around us because as the graph shows we are connected to it. This is the explanation for the abnormally high star rotation rates of stars in spiral galaxies (the reason for the theory of dark matter). The recent discovery that low mass galaxies like NGC 1052-DF2 (some galaxies can appear to be low mass but can have high mass at the center) have predictable star rotation rates is profound information, this is what relativity would predict because there is an insufficient quantity of mass for relativistic velocities to be achieved.
Einstein formulated relativity before the existence of galaxies was confirmed. It is clear that the mass is dilated through the galaxy and not the universe as a whole. For this reason relativity would predict that if you point a detector to a region of space devoid of light you will never see zero radiation.
The belief in black holes gradually came about after television and magazines put that counterintuitive image in peoples minds. If you pose the question "why cant we see light from the galactic center?" the modern answer would be because gravitational forces there are so strong that not even light can escape (even though the mass of the photon is zero). Einstein's (and all other physicists/astronomers knowledgeable about relativity from the 20's, 30's, 40's, and 50's) answer would be because the mass there is partially or completely dilated relative to an Earth bound observer. Einstein's answer explains the greatest mystery in science (the rotation rates of stars in spiral galaxies).

[k-vsalomonsen]

Can you drive around a black hole whit a spaceship. And is it round or flat from the side? The hole cant be round from all sides..

[allurbase]

Would having one of this telescopes in orbit help? maybe it could dump a bunch of harddrives into the atmosphere every year or so?

[jamiboothe]

We have an image from a fantastically distant galactical neighbor`s core, and now, of our own! If we can keep taking images of both, we can watch the progressions in the data of each system...and so much more.