Rajasmita Sahoo Karl Schwarzchild in 1916 calculated a precise solution to Einstein's field equations for general relativity. It's called the Schwarzchild radius. It's the basis for black hole formation, showing that the radius of an object is proportional to its mass. It gives the event horizon of a Schwarzschild black hole. You can use this wikipedia reference https://en.wikipedia.org/wiki/Schwarzschild_radius to get further references, to fully answer your question.

Cheers,

Tom

Rajasmita Sahoo, the event horizon is defined as the region from which light cannot escape. A photon emitted at the centre will escape if it passes the eventual radius of the event horizon before it reaches full size but that will take some time. It follows that the region within the horizon starts at the centre and grows outward, expanding beyond the infalling star remnants as it grows until the whole star has fallen in.

Thank you very much George Dishman and T. H. Ray

How could anyone can answer this question which Black Hole never been observed to this date? BH is just prediction, and prediction is not science.

All the images from 2015 to now are just made up by computer artist.

Javad Fardaei, LIGO has observed more than 100 mergers of binary black holes and the photon spheres of both Sgr A* and the SMBH in M87 have bee directly observed by the Event Horizon Telescope.

JF: All the images from 2015 to now are just made up by computer artist.

Don't be silly, they are the result of processing a vast amount of data obtained by telescopes all over the world.

Black holes are among the most mysterious cosmic objects, much studied but not fully understood, and have been created based on observations.

To solve the mysteries of black holes, it's good to try to think outside the box.

I have a hypothesis that black holes are star of antimatter. The atomic nuclei of antimatter are surrounded by positrons instead of electrons. Electromagnetic radiation is obtained when positrons jump between the positron shells and emit anti electromagnetic radiation. We can't detect that kind radiation with our measuring instruments, which is why these stars behaves like black holes.

https://www.researchgate.net/publication/334896477_The_Positron-Electron_Sea#:~:text=File%20available-,The%20Positron%2DElectron%20Sea,-August%202019

Rajasmita Sahoo : Albert Einstein himself in a robust publication (link Below, but hardly mentioned by official physics) emphatically dismissed the possibility of "Back Holes" even in theory! The following is a copy of his conclusion at the end of this mathematically rich and lengthy publication: "The essential result of this investigation is a clear understanding as to why the "Schwarzschild singularities" do not exist in physical reality. Although the theory given here treats only clusters whose particles move along circular paths it does not seem to be subject to reasonable doubt that more general cases will have analogous results. The "Schwarzschild singularity" does not appear for the reason that matter cannot be concentrated arbitrarily. And this is due to the fact that otherwise the constituting particles would reach the velocity of light.

This investigation arose out of discussions the author conducted with Professor H. P. Robertson and with Drs. V. Bargmann and P. Bergmann on the mathematical and physical significance of the Schwarzschild singularity. The problem quite naturally leads to the question, answered by this paper in the negative, as to whether physical models are capable of exhibiting such a singularity." Albert Einstein. A. Einstein, The Annals of Mathematics, Second Series, Vol. 40, No. 4 (Oct., 1939), pp. 922-936

https://pdfs.semanticscholar.org/8dd0/dfafef0c53c428fdc3b58f8099aafcf7d089.pdf

Jan Lagerström > "I have a hypothesis that black holes are star of antimatter."

It is a reasonable hypothesis in a dialectical, infinite, eternal and ever-changing universe; where separately chance accumulated matter and antimatter in the form of dust particles, clouds, nebulae, stars, clusters of stars etc. are possible. Similarly, chance encounter between these opposite formations of matter-antimatter and their annihilation processes is the source of diffuse gamma ray halo in the galaxies and the catastrophic events like the active galactic nuclei (AGNs), quasars, gamma ray bursts (GRBs) etc. But your notion of anti electromagnetic radiation (photons) may not be reasonable, because bosons like photons are their own anti-particles. Please see:

"The Cosmic Gamma-Ray Halo – New Imperative for a Dialectical Perspective of the Universe": Article THE COSMIC GAMMA-RAY HALO.

"Ambartsumian, Arp and the Breeding Galaxies": http://redshift.vif.com/JournalFiles/V12NO2PDF/V12N2MAL.pdf

Thank you Abdul Malek for the good comment and the referent to THE COSMIC GAMMA-RAY HALO.

I agree with you about gamma radiation in the galaxies.

The anti-electromagnetic radiation was a metaphor because I don’t believe that photons exist. The electromagnetic radiation is in my hypothesis is a pure wave function in electrons surrounding matter and positrons surrounding antimatter and disappears in the bound between them in a gamma-ray hallo. Radiation from antimatter cannot be transfer to matter.

Jan Lagerström : Thanks for your kind words. The two articles cited above were published with the approval of the famous astronomer/astrophysicist Halton (Chip) Arp (some call him the Galileo of modern times), when he was at the Max-Planck Institute at Garching, near Munich, Germany; after being forced out of Palomar in the US. Chip praised the second article (published in “Apeiron”) as “superb”. About Arp: https://www.researchgate.net/post/Can_Halton_Chip_Arps_Name_Be_Erazed_From_History

Rajasmita Sahoo Not only Einstein was right on the question of "Black Hole" in a publication cited above; he was right about his own theories of relativity, admitted in a letter (1954) to his life-long friend Michelle Besso; about a year before his death; ): “I consider it quite possible that physics cannot be based on the field concept, i.e., continuous structure. In that case, nothing remains of my entire castle in the air, gravitation theory included, (and of) the rest of modern physics” A. Pais, Subtle is the Lord …” The Science and the Life of Albert Einstein”, Oxford University Press, (1982) 467,

Einstein's views on his own theories of relativity is now fully vindicated in a new publication: "New Physics -The Negation of Einstein's Theories of Relativity - The Real Phenomenology of Space-Time-Matter-Motion".: Article New Physics -The Negation of Einstein's Theories of Relativi...

Thank you to everyone, your insights and expertise have been immensely helpful and are greatly appreciated.

Dear Rajasmita Sahoo I'm sure you know, Black hole is a prediction, and never been observed to this date if you read fine print.

To my knowledge, nothing in our universe is working with pull/push as our past icons thought.

Javad Fardaei sir, To address the notion that black holes have never been observed and the understanding of forces in the universe, we can follow the astrophysical evidences,

• Indirect Observations: The existence of black holes is supported by numerous indirect observations. This includes the accretion of gas into a black hole, which emits X-rays and other radiation detectable by telescopes. The orbits of stars near the center of our galaxy, Sagittarius A*, have been mapped and indicate the presence of a supermassive black hole.
• Gravitational Wave Detection: The detection of gravitational waves by LIGO and Virgo collaborations is a significant proof. These waves were generated by the collision of two black holes, an event that fits precisely with predictions from Einstein's theory of general relativity.
• The Event Horizon Telescope Image: The EHT project captured an image of the event horizon of a black hole in the galaxy M87 in 2019. This image shows a bright ring formed as light bends in the intense gravity around a black hole that is 6.5 billion times more massive than the Sun. While this is not a direct image of the black hole itself, it is a direct observation of the black hole's shadow and the glowing gas around it, further confirming their existence.

1. In November 1784, the idea of a body so big that even light could not escape was briefly proposed by English astronomical pioneer and clergyman John Michell.

2. In 1915, Albert Einstein developed his theory of general relativity, having earlier shown that gravity does influence light's motion.

3. Only a few months later, Karl Schwarzschild found a solution to the Einstein field equations that describes the gravitational field of a point mass and a spherical mass.

4. In 1931, Subrahmanyan Chandrasekhar calculated, using special relativity, that a non-rotating body of electron-degenerate matter above a certain limiting mass (now called the Chandrasekhar limit at 1.4 M☉) has no stable solutions.

5. A white dwarfslightly more massive than the Chandrasekhar limit will collapse into a neutron star, which is itself stable.

6. In 1939, Robert Oppenheimer and others predicted that neutron stars above another limit (the Tolman–Oppenheimer–Volkoff limit) would collapse further for the reasons presented by Chandrasekhar, and concluded that no law of physics was likely to intervene and stop at least some stars from collapsing to black holes.

7. In 1958, David Finkelsteinidentified the Schwarzschild surface as an event horizon, "a perfect unidirectional membrane: causal influences can cross it in only one direction".

8. In 1963, Roy Kerr found the exact solutionfor a rotating black hole.

9. In 1967, the discovery of pulsars by Jocelyn Bell Burnell.

10. On 11 February 2016, the LIGO Scientific Collaboration and the Virgo collaboration announced the first direct detection of gravitational waves, representing the first observation of a black hole merger.

11. On 10 April 2019, the first direct image of a black hole and its vicinity was published, following observations made by the Event Horizon Telescope (EHT) in 2017 of the supermassive black hole in Messier 87's galactic centre.

Hence, Black holes are no longer just theoretical predictions but are now observed objects in the universe.

To add to what Rajasmita Sahoo noted, here is the current list of LIGO detections, most of which include at least one black hole. This will be significantly extended when the current O4 run results are published.

https://en.wikipedia.org/wiki/List_of_gravitational_wave_observations

Rajasmita Sahoo: You are, unfortunately, like most other budding physicists, are being saturated with official propaganda; taught in the universities around the world. As cited above, Einstein himself strongly dismissed the possibility of "black hole" formation even in theory! All these claims of “proof” and “discoveries” by the charlatans of official physics are contrived, deceptive and even false! These are meant to cover-up the nakedness of their Emperor (Einstein);

There are a number of stars at the centre of the Sagittarius, orbiting the so-called “black hole”. Few years ago, the “astrophysicists” promised us a gigantic cosmic firework (visible to naked eyes), when the star (or cloud) named G2 would pass too close to the hungry “black hole” to escape and would be devoured with a splash of radiation! Well, G2 completed its orbital journey near the hungry monster without even a little scratch!

The truth is that the need for these black/dark cosmic monsters arise simply because the theories of gravity from Newton to Einstein, which predict these monsters; are terribly wrong or false! This terrible fate of cosmology since the Copernican revolution; have been fabricated by official physics at the behest of theology and monopoly capitalism; to be used as the ruling ideas; like previous mythologies of the past history. Please see the next comment

Rajasmita Sahoo : The negation of the faulty theories of gravity and the demolition of the myths of modern cosmology from Newton to Einstein are now accomplished with the promise of positive knowledge of the cosmos:

"New Physics – The Negation of Einstein’s Theories of Relativity": https://rajpub.com/index.php/jap/article/view/9594

Please see the list of other supporting and related previous publications:

 Abdul Malek, THE CONCEPTUAL DEFECT OF THE LAW OF UNIVERSAL GRAVITATION OR FREE FALL: A DIALECTICAL REASSESSMENT OF KEPLERS LAWS: , https://rajpub.com/index.php/jap/article/view/6131

 Abdul Malek, The Mystery of the Lorentz Transform: A Reconstruction and Its Implications for Einstein’s Theories of Relativity and cosmology. , JOURNAL OF ADVANCES IN PHYSICS: Vol. 19 (2021) https://rajpub.com/index.php/jap/article/view/9079

 Abdul Malek, KEPLER – NEWTON – LEIBNIZ – HEGEL , JOURNAL OF ADVANCES IN PHYSICS: Vol. 19 (2021) https://rajpub.com/index.php/jap/article/view/9106

 Abdul Malek, The Philosophy of Space-Time: Whence Cometh Matter and Motion? , JOURNAL OF ADVANCES IN PHYSICS: Vol. 12 No. 2 https://rajpub.com/index.php/jap/article/view/163

 Abdul Malek, Gravity – An Intrinsic Property of Matter! A Qualitative Graviton-Orbital-Band Theory , JOURNAL OF ADVANCES IN PHYSICS: Vol. 14 No. 2 https://rajpub.com/index.php/jap/article/view/7484

 Abdul Malek, QUASARS – POINTERS TO AN INFINITE, ETERNAL AND DIALECTICAL UNIVERSE AND A REPUDIATION OF THE BIG BANG COSMOLOGY , JOURNAL OF ADVANCES IN PHYSICS: Vol. 21 (2023) https://rajpub.com/index.php/jap/article/view/9551

 Abdul Malek, THE NOTHING THAT REALLY IS! , JOURNAL OF ADVANCES IN PHYSICS: Vol. 12 No. 1 https://rajpub.com/index.php/jap/article/view/172