Nobel-Prize laureate Subrahmanyan Chandrasekhar, for whom NASA’s Chandra X-Ray Observatory was named, described black holes as “the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time.”
Strange Cosmic Paradoxes
These strange cosmic paradoxes, which Princeton quantum physicist John Archibald Wheeler coined “black holes,” have no memory, yet are said to contain the earliest memories of the universe, as well as the most recent, while at the same time obliterating all memory by obliterating all its manifestations.
And yet, like a hologram, black holes have two dimensions, in which gravity disappears, but they reproduce an object in three dimensions, aligning with Einstein’s theory of relativity, which describes black holes as three dimensional, simple, spherical, and smooth, as they appear in the famous image of the black hole in M87 captured by the Event Horizon Telescope (EHT) in April 2019. An image, EHT director Shep Deleman described as “one-way doors out of the Universe.”
Chandra X-ray Close-up of the Core of M87, EHT Image of Black Hole below (X-ray: NASA/CXC/Villanova University/J. Neilsen, Radio: Event Horizon Telescope Collaboration)
Do Black Holes Exist in a Higher Dimension?
Do Black Holes exist in a higher dimension? –perhaps the Big Bang is a mirage This video asks profound questions about the existence of black holes in our Universe.
Primordial Black Holes
Shortly after the Big Bang, quantum mechanical fluctuations led to the density distribution of matter that we observe today in the expanding universe. It’s been suggested that some of those density fluctuations might have been large enough to result in black holes peppered throughout the universe. These so-called primordial black holes were first proposed in the early 1970s by Stephen Hawking and collaborators but have never been detected—it’s still not clear if they exist at all.
“Ancient black holes would give us access to physics we would never otherwise be able to do,” wrote Dan Hooper, head of the theoretical astrophysics group at Fermilab, in an email to The Daily Galaxy. If primordial black holes are real, they’d have potential to solve a whole host of the biggest problems in cosmology, not the least being the mystery of dark matter, considered to be the backbone to the structure of the universe.
First-Ever Image of a Black Hole
To celebrate two years since the EHT Collaboration released the first image of the M87 Galaxy Black Hole, the Alma Observatory in Chile shared five impressive things about these incredible objects (edited and expanded upon by The Daily Galaxy). Scientists had long struggled to capture a photograph of a black hole — a region of space with a gravitational pull so strong that not even light can escape it. Black holes, Einstein said, are where God divided by zero.”
The image revealed by the EHT in 2019 shown below consists of a glowing orange ring on a black background. It is an image equal to the famous “Earthrise” photo taken by Apollo 8 astronaut Bill Anders in December 1968
Five Amazing Facts
1. Before knowing what black holes were, in 1784 geologist John Michell called them dark stars. The idea of black holes stems from Albert Einstein’s theory of general relativity, which says that light is affected by gravity. Michell wrote: “If the semi-diameter of a sphere of the same density as the Sun were to exceed that of the Sun in the proportion of 500 to 1, a body falling from an infinite height towards it would have acquired at its surface greater velocity than that of light, and consequently..all light emitted from such a body would be made to return towards it by its own proper gravity.”
Artist impression above of the heart of galaxy NGC 1068, which harbors an actively feeding supermassive black hole. Arising from the black hole’s outer accretion disk, ALMA discovered clouds of cold molecular gas and dust. This material is being accelerated by magnetic fields in the disk, reaching speeds of about 400 to 800 kilometers per second. This material gets expelled from the disk and goes on to hide the region around the black hole from optical telescopes on Earth. Essentially, the black hole is cloaking itself behind a veil of its own exhaust. (NRAO/AUI/NSF; D. Berry / Skyworks)
2. The first simulation of a black hole was a drawing of the accretion disk, made by hand, around a black hole, based on computer calculations by French astrophysicist Jean-Pierre Luminet in 1979 published in Astronomy and Astrophysics, it had a worldwide impact, since this type of object was still highly theoretical. It is an image based on the then supposed physical properties of a black hole and its gas disc, such as its rotation rate and temperature, and on Einstein’s general theory of relativity. (CNRS Phototheque)
3. Black holes are regions in space where gravity is extreme. Everything that comes too close is sucked in, and nothing can ever get out again. Even light, traveling at 300,000 kilometers per second, cannot escape the gravitational grip of a black hole. Stephen Hawking wrote about the black hole’s event horizon: “Consideration of particle emission from black holes would seem to suggest that God not only plays dice, but also sometimes throws them where they cannot be seen.”
4. Black holes cause huge jets of matter event horizon: Most of the matter near the edge of a black hole ends up falling into it. However, some of the surrounding particles escape moments before capture and are propelled into space at great distances in jets. The new image, reported the European Southern Observatory (ESO), captured how the iconic object looks in polarized light showing the bright jets of energy and matter that emerge from M87’s core and extend at least 5000 light-years from its center –one of the galaxy’s most mysterious and energetic features.
5. The Event Horizon Telescope (EHT) collaboration, which produced the first-ever image of a black hole released in 2019, has a new view of the massive object at the Messier 87 (M87) center galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarization, a signature of magnetic fields, this close to the edge of a black hole.
Just as electromagnetic radiation becomes polarized when passing through a polarizing filter, blocking radiation where the electric field is perpendicular to the plane of polarization, the extreme magnetic fields in the accretion disk surrounding the black hole polarize the emitted light. By measuring the strength and orientation of the polarization, astronomers can better understand the magnetic fields in the accretion disks of supermassive black holes.
This image above shows the polarised view of the black hole in M87 –an object larger than our solar system. The lines mark the orientation of polarisation, which is related to the magnetic field around the shadow of the black hole. (EHT Collaboration)
Image credit top of page: Primordial black holes, NASA, ESA, Hubble Heritage Team