Penrose process
The Penrose process( also called Penrose mechanism) is theorised by Roger Penrose as a means whereby energy can be extracted from a rotating black hole.
That extraction can occur if the rotational energy of the black hole is located not inside the event horizon but outside in a region of the Kerr spacetime called the ergosphere in which any particle is necessarily propelled in locomotive concurrence with the rotating spacetime.
All objects in the ergosphere become dragged by a rotating spacetime.
In the process, a lump of matter entering the ergosphere is triggered to split into two parts.
For example, the matter might be made of two parts that separate by firing an explosive or rocket which pushes its halves apart.
The momentum of the two pieces of matter when they separate can be arranged so that one piece escapes from the black hole( it" escapes to infinity"), whilst the other falls past the event horizon into the black hole.
With careful arrangement, the escaping piece of matter can be made to have greater mass- energy than the original piece of matter, and the infalling piece has negative mass- energy.
Although momentum is conserved the effect is that more energy can be extracted than was originally provided, the difference being provided by the black hole itself.
In summary, the process results in a slight decrease in the angular momentum of the black hole, which corresponds to a transference of energy to the matter.
The momentum lost is converted to energy extracted.
The maximum amount of energy gain possible for a single particle via this process is 20.7% in case of uncharged black hole.
The process obeys the laws of black hole mechanics.
A consequence of these laws is that if the process is performed repeatedly, the black hole can eventually lose all of its angular momentum, becoming non-rotating, i.e. a Schwarzschild black hole.
In this case the theoretical maximum energy that can be extracted from an uncharged black hole is 29% of its original mass.
Larger efficiencies are possible for charged rotating black holes.
V404 Cygni
V404 Cygni is a microquasar and a binary system in the constellation of Cygnus.
It contains a black hole with a mass of about and an early K giant star companion with a mass slightly smaller than the Sun.
The star and the black hole orbit each other every 6.47129 days at fairly close range.
Due to their proximity and the intense gravity of the black hole, the companion star loses mass to an accretion disk around the black hole and ultimately to the black hole itself.
The" V" in the name indicates that it is a variable star, which repeatedly gets brighter and fainter over time.
It is also considered a nova, because at least three times in the 20th century it produced a bright outburst of energy.
Finally, it is a soft X- ray transient because it periodically emits short bursts of X-rays.
In 2009, the black hole in the V404 Cygni system became the first black hole to have an accurate parallax measurement for its distance from the Solar System.
Measured by very- long- baseline interferometry using the High Sensitivity Array, the distance is, or light- years.
In April 2019, astronomers announced that jets of particles shooting from the black hole were wobbling back and forth on the order of a few minutes, something that had never before been seen in the particle jets streaming from a black hole.
Astronomers believe that the wobble is caused by the warping of space/ time by the huge gravitational field in the vicinity of the black hole.
The black hole companion has been proposed as a Q star candidate.
Paul L. Stein
Paul Ludwig Stein( 4 February 1892 – 2 May 1951) was an Austrian- born film director with 67 films to his credit.
Stein began his career in Berlin in 1918 and worked exclusively in the German silent film industry until 1926, when he first went to Hollywood, and spent the next five years commuting between Germany and the U.S., where he worked with stars such as Jeanette MacDonald, Lillian Gish and Constance Bennett.
In 1931, Stein relocated to England after gaining a contract with British International Pictures, where he was assigned a number of big- name prestige productions, including some of the popular operetta films of the mid-1930s.
These included" Blossom Time" and" Heart's Desire" starring his boyhood friend Richard Tauber, who also made cameo appearances in two of his post-war films" Waltz Time" and" Lisbon Story".
For most his career, Stein's credits tended to be films primarily aimed at female audiences, although later he also directed crime and spy thrillers.
Stein remained in England for the rest of his life and career, becoming a British citizen in 1938.
Jóhannes Haukur Jóhannesson
Jóhannes Haukur Jóhannesson( born 1980) is an Icelandic actor known for his roles on the series" Game of Thrones" and" The Innocents" and in the films" Atomic Blonde" and" Alpha".
Samir D. Mathur
Samir Dayal Mathur is a theoretical physicist who specializes in string theory and black hole physics.
Mathur is a professor in the Department of Physics at The Ohio State University and a member of the University's High Energy Theory Group.
He was a faculty member at Massachusetts Institute of Technology from 1991–99 and held postdoctoral positions at Harvard University and the Tata Institute of Fundamental Research.
Mathur's research is focused on string theory, black holes, the AdS/ CFT correspondence, and cosmology.
He is best known for developing the Fuzzball conjecture as a resolution of the black hole information paradox.
The Fuzzball conjecture asserts that the fundamental description of black holes is given by a quantum bound state of matter which has the same size as the corresponding classical black hole.
This quantum bound state replaces the event horizon and singularity, and the classical black hole metric is claimed to be an approximate effective description.
In 2009 Mathur published a strong version of the black hole information paradox, strengthening Stephen Hawking's original version by demonstrating that small local corrections to Hawking's semiclassical analysis can not restore unitarity.
This result was obtained by applying Strong Subadditivity of Quantum Entropy to the evaporation of Hawking radiation.
This led to a renewed interest in the information paradox and the development of the 2012 black hole firewall paradox.
A Woman Commands
A Woman Commands is a 1932 American pre-Code film directed by Paul L. Stein and starring Pola Negri, Roland Young, and Basil Rathbone.
C. V. Vishveshwara
C. V. Vishveshwara( 6 March 1938 – 16 January 2017) was an Indian scientist and black hole physicist.
Specializing in Einstein's General Relativity, he worked extensively on the theory of black holes and made major contributions to this field of research since its very beginning.
He is popularly known as the' black hole man of India'.
Ellen Spiro
Ellen Spiro is an American documentary filmmaker.
She is a Guggenheim Fellow, a Fulbright Fellow, a two- time Rockefeller Fellow, and an Emmy Award winner.
She won the National Board of Review's Best Documentary award.
She was short- listed for an Academy Award in the category of Best Long Form Documentary and Producer's Guild Best Documentary award nominee.
Spiro is known for making humorous social issue films for national and international television broadcasts( HBO, PBS, Sundance, BBC) and theatrical release.
In 2010 Spiro directed a nationally broadcast NOW on PBS special Fixing the Future with on- camera host David Brancaccio who visits communities across America using innovative approaches to confront economic crisis with new and sustainable models.
Spiro directed a series of short animated films on" How the New Economy Works".
In 2014 Spiro co- directed a feature adaptation of Fixing the Future which was theatrically released in over 50 cities.
In 2007 she released" Body of War"( co- directed and co-produced with Phil Donahue), which was short- listed for an Academy Award for Best Documentary and won Best Documentary of 2007 by the National Board of Review.
Spiro directed a music video," No More", an original song by Eddie Vedder that he wrote for Body of War.
" No More" was released by Warner Brothers Music, broadcast on MTV and VH1 and viewed over a million times online.
Spiro also co-produced the called featuring songs by Eddie Vedder, Ben Harper, John Lennon, Bruce Springsteen, Bright Eyes, Neil Young, Lupe Fiasco, Serj Tankian and Kimya Dawson.
The album artwork was created by Shepard Fairy and profits from the album were donated to the Iraq Veterans Against the War. Body of War premiered at the Toronto International Film Festival where it won an audience award and garnered a standing ovation.
Eddie Vedder joined Ellen Spiro, Phil Donahue, Tomas Young and Cathy Smith onstage and performed a set of acoustic solo songs to a wildly cheering audience.
Spiro and Donahue were featured on a one- hour" Bill Moyers Journal" special discussing the film.
Additionally, Ellen Spiro and Phil Donahue received a 2007 nomination for Best Documentary from the Producers Guild of America.
Spiro's other award- winning films have been shown broadcast on television worldwide on Public Broadcasting Service| PBS, HBO, BBC, Canadian Broadcasting Corporation| CBC and NHK and in the art world, including multiple screenings at the Museum of Modern Art and the Whitney Museum Biennial exhibition.
Spiro was awarded The Foundation of American Women in Radio and Television ’s Gracie Award for Outstanding Director and Outstanding Documentary for Troop 1500, and is a recipient of a Guggenheim Fellowship, a National Endowment for the Arts Fellowship, a Jerome Foundation Fellowship, a commendation from the Texas State Legislature( Senate Resolution 545) and is a two- time Rockefeller Fellowship recipient.
Her works are housed in the permanent collections of the Academy of Motion Picture Arts and Sciences in Los Angeles, the UCLA Film and Television Archive, Museum of Modern Art in New York, Peabody Collection of The Paley Center for Media and the New York Public Library.
Spiro is Professor Emerita at the University of Texas at Austin Department of Radio- Television- Film where she taught graduate and undergraduate courses in documentary, experimental film and music film production.
She is currently a Visiting Professor at the University of CA at Berkeley.
List of Italian film directors
The following is a list of film directors from Italy.
Atomic Ed and the Black Hole
Atomic Ed and the Black Hole is a documentary released in 2001 by filmmaker, Ellen Spiro.
The documentary was made for HBO's Cinemax Reel Life Series.
Sheila Nevins served as Executive Producer and Lisa Heller served as Supervising Producer.
Karen Bernstein served as Producer.
Laurie Anderson provided her song, Big Science, for the soundtrack.
Ed Grothus (“Atomic Ed”) is a machinist-turned-atomic junk collector who more than 30 years ago quit his job of making atomic bombs and began collecting non-radioactive high-tech nuclear waste discarded from the Los Alamos National Laboratory.
Atomic Ed is the proprietor of “The Black Hole”, a second-hand shop and, next door, curator of the unofficial museum of the nuclear age.
His collection reveals and preserves the history of government waste that was literally thrown in a trash heap.

Question: Do both films Atomic Ed And The Black Hole and A Woman Commands have the directors from the same country?
Answer: no