Hugh Everett III

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Hugh Everett III
Hugh Everett in 1964
Born(1930-11-11)November 11, 1930
DiedJuly 19, 1982(1982-07-19) (aged 51)
Citizenship United States
Alma mater Catholic University of America
Princeton University (Ph.D.)
Known for Many-worlds interpretation
Everett's theorem [1] [2] [3]
ChildrenElizabeth Everett, Mark Oliver Everett
Scientific career
Fields Physics
Operations research
Game theory
Institutions Institute for Defense Analyses
American Management Systems
Monowave Corporation
Doctoral advisor John Archibald Wheeler

Hugh Everett III ( /ˈɛvərɪt/ ; November 11, 1930 – July 19, 1982) was an American physicist who first proposed the many-worlds interpretation (MWI) of quantum physics, which he termed his "relative state" formulation. [lower-alpha 1] In contrast to the then-dominant Copenhagen interpretation, the MWI posits that the Schrödinger equation never collapses and that all possibilities of a quantum superposition are objectively real.


Discouraged by the scorn [5] of other physicists for MWI, Everett ended his physics career after completing his PhD. Afterwards, he developed the use of generalized Lagrange multipliers for operations research and applied this commercially as a defense analyst and a consultant. In poor health later in life, he died at the age of 51 in 1982. He is the father of musician Mark Oliver Everett.

Although largely disregarded until near the end of Everett's lifetime, the MWI received more credibility with the discovery of quantum decoherence in the 1970s and has received increased attention in recent decades, becoming one of the mainstream interpretations of quantum mechanics alongside Copenhagen, pilot wave theories, and consistent histories.

Early life and education

Hugh Everett III was born in 1930 and raised in the Washington, D.C. area. Everett's parents separated when he was young. Initially raised by his mother (Katherine Lucille Everett née Kennedy), he was raised by his father (Hugh Everett Jr) and stepmother (Sarah Everett née Thrift) from the age of seven. [6]

At the age of twelve he wrote a letter to Albert Einstein asking him whether that which maintained the universe was something random or unifying. [4] Einstein responded as follows:

Dear Hugh: There is no such thing like an irresistible force and immovable body. But there seems to be a very stubborn boy who has forced his way victoriously through strange difficulties created by himself for this purpose. Sincerely yours, A. Einstein [4]

Everett won a half scholarship to St. John's College High School in Washington, D.C. From there, he moved to the nearby Catholic University of America to study chemical engineering as an undergraduate. While there, he read about Dianetics in Astounding Science Fiction . Although he never exhibited any interest in Scientology (as Dianetics became), he did retain a distrust of conventional medicine throughout his life. [6]

During World War II his father was away fighting in Europe as a lieutenant colonel on the general staff. After World War II, Everett's father was stationed in West Germany, and Hugh joined him, during 1949, taking a year out from his undergraduate studies. Father and son were both keen photographers and took hundreds of pictures of West Germany being rebuilt. Reflecting their technical interests, the pictures were "almost devoid of people". [6]


Everett graduated from the Catholic University of America in 1953 with a degree in chemical engineering, although he had completed sufficient courses for a mathematics degree as well. He received a National Science Foundation fellowship that allowed him to attend Princeton University for graduate studies. He started his studies at Princeton in the mathematics department, where he worked on the then-new field of game theory under Albert W. Tucker, but slowly drifted into physics. In 1953 he started taking his first physics courses, notably Introductory Quantum Mechanics with Robert Dicke. [6]

During 1954, he attended Methods of Mathematical Physics with Eugene Wigner, although he remained active with mathematics and presented a paper on military game theory in December. He passed his general examinations in the spring of 1955, thereby gaining his master's degree, and then started work on his dissertation that would (much) later make him famous. He switched thesis advisor to John Archibald Wheeler some time in 1955, wrote a couple of short papers on quantum theory and completed his long paper, Wave Mechanics Without Probability in April 1956. [7]

In his third year at Princeton, Everett moved into an apartment which he shared with three friends he had made during his first year, Hale Trotter, Harvey Arnold [8] and Charles Misner. Arnold later described Everett as follows:

He was smart in a very broad way. I mean, to go from chemical engineering to mathematics to physics and spending most of the time buried in a science fiction book, I mean, this is talent. [6]

It was during this time that he met Nancy Gore, who typed up his Wave Mechanics Without Probability paper. Everett married Nancy Gore the next year. [9] [10] The long paper was later retitled as The Theory of the Universal Wave Function .

Wheeler himself had traveled to Copenhagen in May 1956 with the goal of getting a favorable reception for at least part of Everett's work, but in vain. [11] [12] In June 1956 Everett started defense work in the Pentagon's Weapons Systems Evaluation Group, returning briefly to Princeton to defend his thesis after some delay in the spring of 1957. A short article, which was a compromise between Everett and Wheeler about how to present the concept and almost identical to the final version of his thesis, was published in Reviews of Modern Physics Vol 29 #3 454-462, (July 1957), accompanied by an approving review by Wheeler. Everett was not happy with the final form of the article. [6] Everett received his Ph.D. in physics from Princeton in 1957 after completing his doctoral dissertation titled "On the foundations of quantum mechanics." [13]

After Princeton

Everett's attendance marked the transition from academia to commercial work. Hugh Everett at New Mexico 1956 course attedence certicate.jpg
Everett's attendance marked the transition from academia to commercial work.

Upon graduation in September 1956, Everett was invited to join the Pentagon's newly-forming Weapons Systems Evaluation Group (WSEG), managed by the Institute for Defense Analyses. Between 23–26 October 1956 he attended a weapons orientation course managed by Sandia National Laboratories at Albuquerque, New Mexico to learn about nuclear weapons and became a fan of computer modeling while there. In 1957, he became director of the WSEG's Department of Physical and Mathematical Sciences. After a brief intermission to defend his thesis on quantum theory at Princeton, Everett returned to WSEG and recommenced his research, much of which, but by no means all, remains classified. He worked on various studies of the Minuteman missile project, which was then starting, as well as the influential study The Distribution and Effects of Fallout in Large Nuclear Weapon Campaigns. [14] [15]

During March and April 1959, at Wheeler's request, Everett visited Copenhagen, on vacation with his wife and baby daughter, in order to meet with Niels Bohr, the "father of the Copenhagen interpretation of quantum mechanics". The visit was a complete disaster; Everett was unable to communicate the main idea that the universe is describable, in theory, by an objectively existing universal wave function (which does not "collapse"); this was simply heresy to Bohr and the others at Copenhagen. The conceptual gulf between their positions was too wide to allow any meeting of minds; Léon Rosenfeld, one of Bohr's devotees, talking about Everett's visit, described Everett as being "undescribably [sic] stupid and could not understand the simplest things in quantum mechanics". Everett later described this experience as "hell...doomed from the beginning". [16]

However, while in Copenhagen, in his hotel, he started work on a new idea to use generalized Lagrange multipliers for mathematical optimization. Everett's theorem, published in 1963, relates the Lagrangian bidual to the primal problem. [1]

In 1962 Everett accepted an invitation to present the relative-state formulation (as it was still called) at a conference on the foundations of quantum mechanics held at Xavier University in Cincinnati. [16] In his exposition Everett presented his derivation of probability and also stated explicitly that observers in all branches of the wavefunction were equally "real." He also agreed with an observation from the floor that the number of branches of the universal wavefunction was an uncountable infinity. [16]

In August 1964, Everett and several WSEG colleagues started Lambda Corp. to apply military modeling solutions to various civilian problems. During the early 1970s, defense budgets were curtailed and most money went to operational duties in the Vietnam War, resulting in Lambda eventually being absorbed by the General Research Corp.

In 1973, Everett and Donald Reisler (a Lambda colleague and fellow physicist) left the firm to establish DBS Corporation in Arlington, Virginia. Although the firm conducted defense research (including work on United States Navy ship maintenance optimization and weapons applications), it primarily specialized in "analyzing the socioeconomic effects of government affirmative action programs" as a contractor under the auspices of the Department of Justice and the Department of Health, Education and Welfare. [17] For a period of time, the company was partially supported by American Management Systems, a business consulting firm that drew upon algorithms developed by Everett. He concurrently held a non-administrative vice presidency at AMS and was frequently consulted by the firm's founders.

Everett cultivated an early aptitude for computer programming at IDA and favored the TRS-80 at DBS, where he primarily worked for the rest of his life.

Later recognition

In 1970 Bryce DeWitt wrote an article for Physics Today on Everett's relative-state theory, which evoked a number of letters from physicists. These letters, and DeWitt's responses to the technical objections raised, were also published. Meanwhile DeWitt, who had corresponded with Everett on the many-worlds / relative state interpretation when originally published in 1957, started editing an anthology on the many-worlds interpretation of quantum mechanics. In addition to the original articles by Everett and Wheeler, the anthology was dominated by the inclusion of Everett's 1956 paper The Theory of the Universal Wavefunction , which had never been published before. The book was published late in 1973, sold out completely, and it was not long before an article on Everett's work appeared in the science fiction magazine, Analog . [16]

In 1977, Everett was invited to give a talk at a conference Wheeler had organised at Wheeler's new location at the University of Texas at Austin. As with the Copenhagen visit, Everett vacationed from his defense work and traveled with his family. Everett met DeWitt there for the first and only time. Everett's talk was quite well received and influenced a number of physicists in the audience, [16] including Wheeler’s graduate student, David Deutsch, who later promoted the many-worlds interpretation to a wider audience. [16] Everett, who "never wavered in his belief in his many-worlds theory", [18] enjoyed the presentation; it was the first time for years he had talked about his quantum work in public. Wheeler started the process of returning Everett to a physics career by establishing a new research institute in California, but nothing came of this proposal. Wheeler, although happy to introduce Everett's ideas to a wider audience, was not happy to have his own name associated with Everett's ideas. Eventually, after Everett's death, he formally renounced the theory. [16] [19]

Death and legacy

At the age of 51, Everett, who believed in quantum immortality, [6] [20] died suddenly of a heart attack at home [9] in his bed on the night of July 18–19, 1982. Everett's obesity, frequent chain-smoking and alcohol drinking [9] almost certainly contributed to this, although he seemed healthy at the time. A committed atheist, [6] he had asked that his remains be disposed of in the trash after his death. His wife kept his ashes in an urn for a few years, before complying with his wishes. [6] About Hugh's death his son, Mark Oliver Everett, later said:

I think about how angry I was that my dad didn't take better care of himself. How he never went to a doctor, let himself become grossly overweight, smoked three packs a day, drank like a fish and never exercised. But then I think about how his colleague mentioned that, days before dying, my dad had said he lived a good life and that he was satisfied. I realize that there is a certain value in my father's way of life. He ate, smoked and drank as he pleased, and one day he just suddenly and quickly died. Given some of the other choices I'd witnessed, it turns out that enjoying yourself and then dying quickly is not such a hard way to go. [21]

Of the companies Everett initiated, only Monowave Corporation still exists (in Seattle as of March 2015). It is managed by co-founder Elaine Tsiang, who received a Ph.D. in physics under Bryce DeWitt at the University of North Carolina at Chapel Hill before working for DBS as a programmer.

Everett's daughter, Elizabeth, died by suicide in 1996 (saying in her suicide note that she wished her ashes to be thrown out with the garbage so that she might "end up in the correct parallel universe to meet up w[ith] Daddy"), [22] and in 1998, his wife, Nancy, died of cancer. Everett's son, Mark Oliver Everett, who found Everett dead, is also known as "E" and is the main singer and songwriter for the band Eels. The Eels album Electro-Shock Blues , which was written during this time period, is representative of these deaths.

Mark Everett explored his father's work in the hour-long BBC television documentary Parallel Worlds, Parallel Lives . [23] [24] [25] [26] The program was edited and shown on the Public Broadcasting Service's Nova series in the USA during October 2008. [27] [28] [29] In the program, Mark mentions how he wasn't aware of his father's status as a brilliant and influential physicist until his death in 1982.

See also


  1. It is often thought that Everett disliked the term "many-worlds", which was coined by Bryce DeWitt, but David Deutsch, having met Everett for dinner in 1977, says that Everett was actually excited by the term and defended it. [4]

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The Copenhagen interpretation is a collection of views about the meaning of quantum mechanics principally attributed to Niels Bohr and Werner Heisenberg. It is one of the oldest of numerous proposed interpretations of quantum mechanics, as features of it date to the development of quantum mechanics during 1925–1927, and it remains one of the most commonly taught.

Many-worlds interpretation Interpretation of quantum mechanics which denies the collapse of the wavefunction.

The many-worlds interpretation (MWI) is an interpretation of quantum mechanics that asserts that the universal wavefunction is objectively real, and that there is no wavefunction collapse. This implies that all possible outcomes of quantum measurements are physically realized in some "world" or universe. In contrast to some other interpretations, such as the Copenhagen interpretation, the evolution of reality as a whole in MWI is rigidly deterministic. Many-worlds is also called the relative state formulation or the Everett interpretation, after physicist Hugh Everett, who first proposed it in 1957. Bryce DeWitt popularized the formulation and named it many-worlds in the 1960s and 1970s.

Multiverse Hypothetical group of multiple universes

The multiverse is a hypothetical group of multiple universes. Together, these universes comprise everything that exists: the entirety of space, time, matter, energy, information, and the physical laws and constants that describe them. The different universes within the multiverse are called "parallel universes", "other universes", "alternate universes", or "many worlds".

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Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science.

Quantum suicide is a thought experiment in quantum mechanics and the philosophy of physics. Purportedly, it can falsify any interpretation of quantum mechanics other than the Everett many-worlds interpretation by means of a variation of the Schrödinger's cat thought experiment, from the cat's point of view. Quantum immortality refers to the subjective experience of surviving quantum suicide. This concept is sometimes conjectured to be applicable to real-world causes of death as well.

The de Broglie–Bohm theory, also known as the pilot wave theory, Bohmian mechanics, Bohm's interpretation, and the causal interpretation, is an interpretation of quantum mechanics. In addition to the wavefunction, it also postulates an actual configuration of particles exists even when unobserved. The evolution over time of the configuration of all particles is defined by a guiding equation. The evolution of the wave function over time is given by the Schrödinger equation. The theory is named after Louis de Broglie (1892–1987) and David Bohm (1917–1992).

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The many-minds interpretation of quantum mechanics extends the many-worlds interpretation by proposing that the distinction between worlds should be made at the level of the mind of an individual observer. The concept was first introduced in 1970 by H. Dieter Zeh as a variant of the Hugh Everett interpretation in connection with quantum decoherence, and later explicitly called a many or multi-consciousness interpretation. The name many-minds interpretation was first used by David Albert and Barry Loewer in 1988.

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  1. 1 2 Lemaréchal (2001, pp. 125–126): Lemaréchal, Claude (2001). "Lagrangian relaxation". In Michael Jünger and Denis Naddef (ed.). Computational combinatorial optimization: Papers from the Spring School held in Schloß Dagstuhl, May 15–19, 2000. Lecture Notes in Computer Science. 2241. Berlin: Springer-Verlag. pp. 112–156. doi:10.1007/3-540-45586-8_4. ISBN   978-3-540-42877-0. MR   1900016. S2CID   9048698.
  2. Everett (1963)
  3. Everett (1957b)
  4. 1 2 Shikhovstev, Eugene B.; Ford, Kenneth W. (2003). "Everett" . Retrieved December 30, 2019.
  5. "The Many Worlds of Hugh Everett" by Peter Byrne, from Scientific American, December 2007
  6. 1 2 3 4 5 6 7 8 9 Peter Byrne (2010). The Many Worlds of Hugh Everett III: Multiple Universes, Mutual Assured Destruction, and the Meltdown of a Nuclear Family. Oxford University Press. p. 29. ISBN   978-0-19-955227-6.
  7. Fabio Freitas, Os estados relativos de Hugh Everett III: uma análise histórica e conceitual. Programa de Pós-Graducação em Ensino, Filosofia e História das Ciências. 2007 "Archived copy" (PDF). Archived from the original (PDF) on December 18, 2008. Retrieved December 18, 2008.CS1 maint: archived copy as title (link)
  8. "Harvey J. Arnold, Obituary". 2013.
  9. 1 2 3 Mark Oliver Everett, Things the Grandchildren Should Know, ISBN   978-0-316-02787-8
  10. Eugene Shikhovtsev, Biographical Sketch of Hugh Everett, III, Eugene Shikhovtsev's Biography of Everett, maintained by Max Tegmark
  11. Olival Freire Jr (2005). "Science and exile: David Bohm, the hot times of the Cold War, and his struggle for a new interpretation of quantum mechanics". arXiv: physics/0508184 .
  12. Freire, Olival (2005). "Science and exile: David Bohm, the cold war, and a new interpretation of quantum mechanics" (PDF). Historical Studies in the Physical and Biological Sciences. 36: 1–34. doi:10.1525/hsps.2005.36.1.1. Archived from the original (PDF) on March 26, 2012. Retrieved August 7, 2011.
  13. Everett, Hugh (1957). On the foundations of quantum mechanics.
  14. Hugh Everett III and George E.Pugh, "The Distribution and Effects of Fallout in Large Nuclear-Weapon Campaigns", in Biological and Environment Effects of Nuclear War, Hearings Before the Special Sub-Committee on Radiation of the Joint Congressional Committee on Atomic Energy, June 22–26, 1959, Washington, D.C., U.S. Government Printing Office, 1959.
  15. Cf. Dr. Linus Pauling Nobel Peace Prize 1962 lecture (and reprinted in Peace by Frederick W. Haberman, Irwin Abrams, Tore Frängsmyr, Nobelstiftelsen, Nobelstiftelsen (Stockholm), published by World Scientific, 1997 ISBN   981-02-3416-3), delivered on December 11, 1963, in which he mentioned the work by Pugh and Everett regarding the risks of nuclear profliferation and even quoted them from 1959. Pauling said: "This is a small nuclear attack made with use of about one percent of the existing weapons. A major nuclear war might well see a total of 30,000 megatons, one-tenth of the estimated stockpiles, delivered and exploded over the populated regions of the United States, the Soviet Union, and the other major European countries. The studies of Hugh Everett and George E. Pugh [21], of the Weapons Systems Evaluation Division, Institute of Defense Analysis, Washington, D.C., reported in the 1959 Hearings before the Special Subcommittee on Radiation, permit us to make an estimate of the casualties of such a war. This estimate is that sixty days after the day on which the war was waged, 720 million of the 800 million people in these countries would be dead, sixty million would be alive but severely injured, and there would be twenty million other survivors. The fate of the living is suggested by the following statement by Everett and Pugh: 'Finally, it must be pointed out that the total casualties at sixty days may not be indicative of the ultimate casualties. Such delayed effects as the disorganization of society, disruption of communications, extinction of livestock, genetic damage, and the slow development of radiation poisoning from the ingestion of radioactive materials may significantly increase the ultimate toll.' ..."
  16. 1 2 3 4 5 6 7 Osnaghi, Stefano; Freitas, Fabio; Olival Freire, Jr (2009). "The Origin of the Everettian Heresy" (PDF). Studies in History and Philosophy of Modern Physics. 40 (2): 97–123. Bibcode:2009SHPMP..40...97O. doi:10.1016/j.shpsb.2008.10.002. Archived from the original (PDF) on May 28, 2016. Retrieved August 12, 2009.
  17. "The Many Worlds of Hugh Everett".
  18. Aldhous, Peter (November 24, 2007). "Parallel lives can never touch". New Scientist (2631). Retrieved November 21, 2007..
  19. Gardner, Martin (July 2003). "Multiverses and Blackberries" . Are Universes Thicker Than Blackberries?. New York: W. W. Norton & Company. ISBN   978-0-393-05742-3.
  20. See Keith Lynch's recollections in Eugene Shikhovtsev's Biography of Everett
  21. Things the Grandchildren Should Know, ISBN   978-0-316-02787-8, pg 235
  22. Peter Byrne (2010). The Many Worlds of Hugh Everett III: Multiple Universes, Mutual Assured Destruction, and the Meltdown of a Nuclear Family. Oxford University Press. p. 352. ISBN   978-0-19-955227-6. A few days after her 39th birthday, Liz succeeded in killing herself ... She left a note, that read, in part: '... Please sprinkle me in water...or the garbage, maybe that way I'll end up in the correct parallel universe w/ Daddy.'
  23. Last night's TV: Parallel Worlds, Parallel Lives, Nancy Banks-Smith, Guardian blog, 27 November 2007.
  24. Parallel Worlds, Parallel Lives BBC Four documentary about Eels founder Mark Everett and his father Archived 2008-02-14 at the Wayback Machine , Band Weblogs, 16 November 2007.
  25. " Parallel Worlds, Parallel Lives", BBC Press Release
  26. "Parallel Worlds, Parallel Lives", BBC iPlayer
  27. Parallel Worlds, Parallel Lives", PBS Nova TV program, October 2008.
  28. Healy, Pat, "‘Nova’ came for his soul: Eels front man on the healing power of a science doc about his dad" Archived 2011-07-15 at the Wayback Machine , Metro newspaper, October 21, 2008.
  29. Hugh Everett: New film tackles "many worlds" theory of quantum mechanics 60 second science, Scientific American blog, by Jordan Lite and George Musser

Many-worlds sources

Operations research sources

Biographical sources