translated from Spanish: How the black hole photo shows that Einstein was right: the image, explained by one of the scientists who made it possible

The image of a black hole 6,500 million times more massive than the Sun, at a distance of more than 50 million light years from Earth, made Wednesday the owners of the news media.
“An absolute Monster”: this is the first photo of a black hole but what those colors and silhouettes in the photo? And why the circular shape of the “ring of fire” around the black hole shows that, once again, Einstein was right?
They are the questions that we put to one of the scientists of the project Events Horizon Telescope, or EHT, which combined the power of observatories to thousands of km for the image on BBC world.
How scientists combined the power of telescopes thousands of km in the EHT to achieve the first photograph of a black hole the Spanish astronomer José Luis Gómez contributed to the development of one of the algorithms that made possible the photo, and researcher of the Instituto de Astrofísica de Andalucía (CSIC).
What is it seen in the famous image?
“What we see is material that shines, that it is falling into the black hole in the dark area inside, which is the area that we call the event horizon.” That’s where all the light is captured by the black hole and we have the complete darkness “, said Gomez.
The ring of fire shines because, as noted by the Spanish astronomer, material that is falling is compressed.
“There is much friction between the material and that makes heat up a lot, is heated so that it emits radiation across the electromagnetic spectrum”.
The black hole is delineated by a bright ring, which corresponds to superheated gas falling in the gravitational well and emit Radiacionpor elsewhere, in the dark area of the interior, all light is captured. And that darkness only looks to be outlined by the material that is on the edge and falls into the black hole.
That edge is referred to as the shadow of the black hole, the closest we can get to it.
In terms of the color red, Gomez clarified that “it is not a real color, the image is in fact taken at wavelengths that our eyes are not able to appreciate, like the radio”.
“The color is that we felt that it better represented the image.”
What is a black hole (and what possibilities there are that the earth fall into one) why the photo confirms Einstein’s predictions?
The circular shape that has the material falling into the black hole is consistent with the predictions of the theory of relativity, said Gomez.
“There are other theories that say that if gravity behaved differently to what the general theory of relativity, the form may be more flat, similar to a rugby ball”.
The shape is circular because gravity depends only on the distance to the object, but not the direction in which you find yourself, said astronomer.
The circular shape of the material falling into the black hole is consistent with the predictions of Einstein “imagine that you’re watching the Earth from afar, into orbit.” The Earth’s gravity does not depend on whether you’re at the North Pole or the South Pole, is no more in London than in Washington, because it depends only on the distance that you are from the center of the Earth.
“And that makes the Earth round because gravity is compressing the entire mass of the Earth to form a ball, gravity is the same in all the land,” said Gomez.
The same phenomenon explains why the planets and stars are circular.
The same thing happens in a black hole, gave Gomez, “only that gravity is so intense to produce that hole in space-time, but the shape is circular”.
The Spanish scientist explained that when the black hole rotates at maximum speed the circular shape is slightly flat, but that also the theory of relativity predicted.
“With the image that we show yesterday do not have sufficient resolution to determine whether there is actually a slight deviation in the circularity that may be associated with rotation, but if we knew that it had to be fundamentally circular”.
Is it really a photo?
It is something that several people have asked to Gomez and the astronomer has keen to make it clear.
“It is a photo,” said the researcher from the Institute of Astrophysics of Andalusia.
There are different ways to get a photo. In the case of the cell phone, a camera with a lens registers light photons in pixels.
In the case of the black hole, “the photo is obtained thanks to an interference pattern, which in a way perfectly known in mathematics gives you an image using what is called a transformed of Fourier”.
The image was captured by combining the power of observatories to thousands of km, as soul, the Grand Milimetrico-submilimetrico set of Atacama, in Chile “perhaps the most visual example is that this technique we use – called interferometry – is also used in medicine. A CT (computed tomography) uses exactly the same technique we use for this image.
“What we have is a real image. What happens is that our eyes do not have the resolution having the instruments”.
“We can’t see it because it is very far, we need to have an eye that was able to read a newspaper that someone holds in Paris when we’re sitting in New York, to give you an idea.”
“If we were beside the person in Paris, we would see it, is the same. “If we were equally about the black hole with our own eyes would see the image that we got yesterday”, explained.
How does feel José Luis Gómez on a personal level?
“What I feel is an admiration for the theory of relativity, it is a satisfaction to see that actually Einstein was right,” said astronomer.
“But in this, what from the personal point of view more surprises me is to think that black holes may exist, it is a concept that is hard to people to imagine, is an area where the universe ceases to exist as such”.
José Luis Gómez worked on the development of one of the algorithms that allowed to obtain the famous photo of the black hole “people were unbelieving and see that image, see it with your own eyes makes you believe.
“It feels a kind of shudder to imagine that in nature, in the universe, there are those objects. Once you have crossed the event horizon door not you again.
“It is a door outside our universe is like dying, because you die already you can not always live, cross it and already you can not return to our universe, is really amazing”.