To assess the effectiveness of Modeling Instruction, Hestenes and his students developed the Force Concept Inventory, a concept inventory tool for evaluating student understanding of introductory physics.

Hestenes has been a principal investigator for NSF grants seeking to teach physics through modeling and to measure student understanding of physics models at both the high school and university levels.

Hestenes has worked in mathematical and theoretical physics, geometric algebra, neural networks, and cognitive research in science education.

He points out that contributions were made by many individuals, and Clifford himself used the term “ geometric algebra ” which reflects the fact that this approach can be understood as a mathematical formulation of geometry, whereas, so Hestenes asserts, the term “ Clifford algebra ” is often regarded as simply “ just one more algebra among many other algebras ”, which withdraws attention from its role as a unified language for mathematics and physics.

From 1964 to 1966, Hestenes was an NSF Postdoctoral Fellow at Princeton with John Archibald Wheeler.

* Hestenes ' homepage on geometric calculus at ASU

* David Hestenes at the Mathematics Genealogy Project

In 1878, the year before his death, Clifford expanded upon Grassmann's Ausdehnungslehre to form what are now usually called Clifford algebras in his honor although Clifford himself chose to call them " geometric algebras " and this term was repopularized by Hestenes in the 1960s.

Well-known recipients include Nobel laureates Robert Andrews Millikan, Edward M. Purcell, Richard Feynman, Isidor I. Rabi, Norman F. Ramsey, Hans Bethe, and Carl Wieman ; as well as Arnold Sommerfeld, George Uhlenbeck, Jerrold Zacharias, Philip Morrison, Melba Phillips, Victor Weisskopf, Gerald Holton, John A. Wheeler, Frank Oppenheimer, Robert Resnick, Carl Sagan, Freeman Dyson, Daniel Kleppner, and Lawrence Krauss, and Anthony French, David Hestenes, Robert Karplus, Robert Pohl, and Francis Sears.

David Orlin Hestenes, Ph. D. ( born May 21, 1933 ) is a theoretical physicist and science educator.

David Orlin Hestenes ( eldest son of mathematician Magnus Hestenes ) was born 1933 in Chicago Illinois.

A serendipitous encounter with lecture notes by mathematician Marcel Riesz inspired Hestenes to study a geometric interpretation of Dirac matrices.

Hestenes followed this in 1987 with appointment as the first Visiting Scholar in the Department of Cognitive and Neural Systems ( Boston University ) and a period of neuroscience research.

Hestenes emphasizes the important role of the mathematician Hermann Grassmann for the development of geometric algebra, with William Kingdon Clifford building on Grassmann's work.

Hestenes ' work has been applied to Lagrangian field theory, formulation of a gauge theory of gravity alternative to general relativity by Lasenby, Doran and Gull, which they call gauge theory gravity ( GTG ), and it has been applied to spin representations of Lie groups.

Most recently, it led Hestenes to formulate conformal geometric algebra, a new approach to computational geometry.

Since 1980, Hestenes has been developing a Modeling Theory of science and cognition, especially to guide the design of science instruction.

After a decade of education research to develop and validate the approach, Hestenes was awarded grants from the National Science Foundation for another decade to spread the Modeling Instruction Program nationwide.

* D. Hestenes: New Foundations for Classical Mechanics, Foundamental Theories of Physics, 2nd ed., Springer Verlag, 1999, ISBN 978-0792355144

* D. Hestenes, A. Weingartshofer ( eds.

Also, " Absalom, Absalom Would I die for you my son, I would have it all undone, The way it all came down " is found on the 1998 album Largo in the song " Gimme A Stone ".

A 1998 case study found that users would consult the help menu for an average of two or three screens, abandoning the assistance if desired results weren ’ t found by that time.

A 1998 United States Supreme Court decision found most of the island to be part of New Jersey.

A 2003 study looking at the Flynn effect in Kenya between 1984 and 1998 found that the increase was best explained by parents ' literacy, family structure, and children's nutrition and health.

" The same authors in a more comprehensive 2008 study, again on Danish male conscripts, found that there was a 1. 5 points increase between 1988 and 1998, but a 1. 5 points decrease between 1998 and 2003 / 2004.

In a later work ( 1998 ), Davidson states that the description of Hel found in chapter 33 of Gylfaginning " hardly suggests a goddess.

A 1998 poll conducted by the American Museum of Natural History found that seventy percent of biologists believe that we are in the midst of an anthropogenic extinction.

Pressley, VanEtten, Yokoi, Freebern, and VanMeter ( 1998 ) found that learners tended to learn far better by focusing on the content of learning material rather than worrying over any one particular form of note taking.

* Semper Mars ( 1998 ) by Ian Douglas depicts the Cydonia region of Mars as home to ancient alien ruins where mummified early humans are found in 2040.

* 1998 – Matthew Shepard, a gay student at the University of Wyoming, is found tied to a fence after being savagely beaten by two young adults in Laramie, Wyoming.

* On July 16, 1998, CERT reported an incident where an attacker had found 186, 126 encrypted passwords.

A 1998 study by South Africa's Centre for the Study of Violence and Reconciliation & the Khulumani Support Group, which surveyed several hundred victims of human-rights abuse during the Apartheid era, found that most felt that the TRC had failed to achieve reconciliation between the black and white communities.

A study of 6, 000 pregnant women in 1998 " found that while the national average in Britain is 106 boys born to every 100 girls, for vegetarian mothers the ratio was just 85 boys to 100 girls ".

The final report of the South African Truth and Reconciliation commission, issued in 1998, found " Ms Winnie Madikizela Mandela politically and morally accountable for the gross violations of human rights committed by the MUFC.

** Dr. Harold Shipman is found guilty of murdering 15 patients between 1995 and 1998 at Hyde, Greater Manchester, and sentenced to life imprisonment.

At the Russian parliamentary elections in 1995, with a threshold excluding parties under 5 %, more than 45 % of votes were unrepresented ( in 1998, Russian Constitutional Court found the threshold legal, taking into account limits in its use ).

The US virus was very closely related to a lineage 1 strain found in Israel in 1998.

In the 1990s, a 15-second clip filmed in Multicolor during the rehearsal of a scene in Animal Crackers was found and aired as a part of the AMC documentary Glorious Technicolor ( 1998 ).

Mazara made national news in March 1998, when a bronze statue called the Dancing Satyr ( Satiro Danzante ) was found off the port, at a depth of 500 meters in the Strait of Sicily by a local fishing boat.

Sybert, 1998 found that more than 50 % of the cardiovascular malformations observed in her study of individuals with Turner syndrome were bicuspid aortic valves or coarctation of the aorta, alone or in combination.

in 1998 reported on their similar study, in which they found that 13 % of uncles of gay brothers on the maternal side were homosexual, compared to 6 % on the paternal side.

Much of what was contained in the Sunningdale Agreement found its way into the Good Friday Agreement of 1998, which was once described by the then deputy leader of the SDLP, Seamus Mallon, as " Sunningdale for slow learners ", a reference to the failed power-sharing deal of 1973.

The Declaration is not legally binding, however the United States chose in 1998 to pass the International Religious Freedom Act, creating the Commission on International Religious Freedom, and mandating that the United States government take action against any country found to violate the religious freedoms outlined in the Universal Declaration of Human Rights.