'On the edge of what we know...'

The heat of black holes is a quantum effect upon an object, the black hole, which is gravitational in nature. It is the individual quanta of space, the elementary grains of space, the vibrating 'molecules' that heat the surface of black holes and generate black hole heat. This phenomenon involves three sides of the problem: quantum mechanics, general relativity and thermal science. The heat of black holes is like the Rosetta Stone of physics, written in a combination of three languages — Quantum, Gravitational and Thermodynamic — still awaiting decipherment in order to reveal the true nature of time.

Carlo Rovelli

Image via wikipedia

Mass ends in B flat

In 2003, [astronomers] discovered the longest, oldest, lowest note in the universe — a black hole’s song... Although it is too low and deep for humans to hear, the B flat note, 57 octaves below middle C, appeared as sound waves that moved out from explosive events at the edge of a supermassive black hole in the galaxy NGC 1275. 

The notes stayed in the galaxy and never reached us, but we couldn’t have heard them anyway. The lowest note the human ear can detect has an oscillation period of one-twentieth of a second. This B flat’s period was 10 million years.

Joanna Klein An Earthling's guide to black holes

Supermassive black holes — a million to a billion times more massive than our sun — exist only in the center of a galaxy. At the center of the Milky Way, 26,000 light-years from Earth, scientists are hoping to make an image of Sagittarius A*, which is believed to be our own supermassive black hole, with the mass of four million suns.

Image from Utriusque Cosmi by Robert Fludd (1622)

SDSS J0100+2802

The black hole at the centre of our galaxy has a mass about three million times that of our sun. 

The black hole at the centre of the ultra luminous quasar SDSS J0100+2802 is twelve billion times more massive than the sun. 

The luminosity of this quasar is 420 trillion times greater than that of our sun.

  — sci-news.com

The winds blasting out of the quasar PDS 456 carry more energy every second than is emitted by more than a trillion suns. 

Image is artist's impression of ULAS J1120+0641. Credit: ESO/M.Kornmesser.

Signposts

At a talk for non-specialists on 21 February, David Tong outlined three big problems in physics [1], which I oversimplify/misrepresent as follows:

Dark energy.  We've known for nearly a hundred years that the universe is expanding. It as if there is an antigravity force causing everything to repel everything else. We have no idea what it is. It’s 70% of the energy of the universe, it’s increasing all the time and we don’t understand it. Our best calculations are wrong by a factor of 10⁶⁰ .

Black holes.  Information that goes into a black hole is lost forever. It does not reappear in Hawking radiation. But this cannot be.

Holography. It may be that our three dimensional world is actually a mirage. The correct description will be one in which the laws of physics are written on a two dimensional surface, and the laws of physics we can see in the universe are encoded on this surface in the same way that a hologram encodes a three dimensional surface.

So, Tong concluded, there is a lot in the fundamental physics that we simply don’t understand, and that it seems unlikely we’re going to get guidance from experiment. Looking to history, however, it is precisely when there is a crisis that physics has thrived. He is optimistic about progress.


Note [1]: Some people say there are three great mysteries in science as a whole: the origin of the universe, the origin of life and the origin of consciousness.

Image: Douglas Griffin