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Topic: Abhay Ashtekar

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	Loop quantum gravity - Wikipedia, the free encyclopedia
		In 1986 physicist Abhay Ashtekar reformulated Einstein's field equations of general relativity using what have come to be known as Ashtekar variables, a particular flavor of Einstein-Cartan theory with a complex connection.
		In the Ashtekar formulation, the fundamental objects are a rule for parallel transport (technically, a connection) and a coordinate frame (called a vierbein) at each point.
		Because the Ashtekar formulation was background-independent, it was possible to use Wilson loops as the basis for a nonperturbative quantization of gravity.
	en.wikipedia.org /wiki/Objections_to_the_theory_of_loop_quantum_gravity (2043 words)

	JLab in the News - Taste-Testing a Recipe for the Cosmos
		SANTA BARBARA, Calif. -- Dr. Abhay Ashtekar, the leader of a worldwide effort to unify the two most profound, abstract and mathematically baroque theories of physics discovered in this century, is sprinkling frozen mango cubes on scoops of vanilla ice cream.
		The equations that resulted were later shown to predict the polymers by Dr. Ashtekar, Dr. Carlo Rovelli of the Center for Theoretical Physics at the University of Marseilles in France and Dr. Lee Smolin of Pennsylvania State University.
		Ashtekar freely points out that no one yet knows if this conception is right and that nature has actually chosen to fricassee space at the smallest scales.
	www.jlab.org /news/articles/1999/cosmos.html (2099 words)

	Welcome to Little India (Site not responding. Last check: 2007-10-22)
		Abhay Ashtekar is leading a worldwide effort to reconcile relativity theory with quantum mechanics.
		Abhay Ashtekar, 49, is the director of the Center for Gravitational Physics and Geometry at Penn State University in Pennsylvania.
		Ashtekar has written or edited five books and over 140 papers, and this questioning of the universe probably had its roots in the intense reading he did on mathematics and cosmology in his growing years in various small towns in Maharashtra.
	www.asanet.com /achal/archive/Jun99/vision.htm (1654 words)

	Gravedad cuántica de bucles - Wikipedia
		En 1986 el físico Abhay Ashtekar reformuló las ecuaciones del campo de la relatividad general de Einstein usando las qué han venido a ser conocidas como las variables de Ashtekar, un enfoque particular de la teoría de Einstein-Cartan con una conexión compleja.
		En la formulación de Ashtekar, los objetos fundamentales son una regla para el transporte paralelo (técnicamente, una conexión) y un marco coordinado (llamado un vierbein vielbein, tétrodo) en cada punto.
		La cuantización de la gravedad en la formulación de Ashtekar fue basada en los bucles de Wilson, una técnica desarrollada en los años 70 para estudiar el régimen de interacción fuerte de la cromodinámica cuántica.
	es.wikipedia.org /wiki/Gravedad_cu%E1ntica_de_bucles (2341 words)

	The Telegraph - Calcutta : KnowHOW (Site not responding. Last check: 2007-10-22)
		According to Ashtekar, it was John Mitchel, a British cleric, who in 1784 came to the conclusion that there could be stars so massive that the escape velocity from them might be faster than even the speed of light.
		Ashtekar lamented that Hawking’s conceding the bet last September was “reported in the press, instead of a science journal.” He made it clear that he wasn’t convinced by Hawking’s arguments from whatever he could find on the topic on Internet.
		According to Ashtekar, the efforts to analyse fl hole evaporation by mixing general relativity with the two other pillars of physics, statistical mechanics and quantum mechanics, have indicated a startling possibility — that space may not be a continuous, smooth entity.
	www.telegraphindia.com /1050110/asp/knowhow/story_4215567.asp (721 words)

	Ashtekar variables - Wikipedia, the free encyclopedia
		In theoretical physics, Ashtekar (new) variables (named after Abhay Ashtekar who invented them) represent an unusual way to rewrite the metric on the three-dimensional spatial slices in terms of a SU(2) gauge field and its complementary variable.
		Ashtekar variables are the key building block of loop quantum gravity.
		These rules do not follow from the metric tensor and its quantization, but rather from the special global properties of Ashtekar's field redefinition.
	en.wikipedia.org /wiki/Ashtekar_variables (196 words)

	Physics Help and Math Help - Physics Forums - new Ashtekar: Gravity and the Quantum
		Clearly Ashtekar does accept unitarity as a valid criterion for quantum gravity theories since he cites its lack as a reason for abandoning the high energy modification of naive quantum gravity, even specificallly mentioning non conservation of probability.
		The point is (as I think you can tell from Ashtekar) that the perturbative analysis of the "covariant" approach avoids the "problem of time" and comes up with a time-evolution operator----which of course should be probability-preserving but lets keep the language clean and say that it should be unitary.
		Therefore Ashtekar recognizes unitarity as an appropriate criterion when he is discussing perturbative analysis connected with the "cov" approach, just on pages 5, 6, 7.
	www.physicsforums.com /printthread.php?t=47665 (1484 words)

	3 History of Loop Quantum Gravity, Main Steps
		Soon after the introduction of the classical Ashtekar variables, Ted Jacobson and Lee Smolin realized in [128] that the Wheeler-DeWitt equation, reformulated in terms of the new variables, admits a simple class of exact solutions: the traces of the holonomies of the Ashtekar connection around smooth non-selfintersecting loops.
		Ashtekar, Husain, Loll, Marolf, Rovelli, Samuel, Smolin, Lewandowski, Marolf, Thiemann.
		] Ashtekar and Lewandowski set the basis of the differential formulation of loop quantum gravity by constructing its two key ingredients: a diffeomorphism invariant measure on the space of (generalized) connections, and the projective family of Hilbert spaces associated to graphs.
	relativity.livingreviews.org /Articles/lrr-1998-1/node6.html (1734 words)

	Abhay Ashtekar - Wikipedia, the free encyclopedia
		Abhay Ashtekar (born July 5, 1949) completed his undergraduate education in India.
		He studied under Robert Geroch in the University of Chicago, receiving his Ph.D. in 1974.
		As the creator of Ashtekar variables, he is one of the founders of loop quantum gravity.
	en.wikipedia.org /wiki/Abhay_Ashtekar (130 words)

	Rediff On The NeT: The Rediff Profile/ Dr Abhay Ashtekar
		On April 21, Abhay Ashtekar, a notorious late-riser, woke up at 7 am Pacific time and put in a call to a colleague at Penn State University, where he is Director of the Center for Gravitational Physics and Geometry.
		Later the same day Dr Ashtekar, who was in Santa Barbara for a six-month workshop, once again took time from his busy day to call Brewster and leave a message thanking her for all the work she had done.
		Dr Ashtekar, 49, is a world-renowned physicist and leader of a worldwide effort to reconcile Einstein's theory of relativity with the principles of quantum mechanics.
	www.rediff.com /news/1999/may/15us2.htm (270 words)

	[No title]
		Pomocí nového oboru fyziky, kvantové geometrie, nebo také "smyčkové kvantové gravitace" (loop quantum gravity) se Ashtekar přiblížil k naplnění tohoto snu a snad také k zodpovězení základních otázek fyziky, které se týkají záhad velkého třesku a černých děr.
		Ashtekar přirovnává spinové sítě, matematicky popsané jako grafy, ke stavebnici z jednorozměrných vláken podobných polymerům.
		Ashtekar také pracuje na nové formulaci kvantové teorie s cílem ještě více ji zobecnit tak, aby byla slučitelná s obecnou teorií relativity a aby řešila některé problémy své interpretace.
	natura.baf.cz /natura/2004/6/20040604.html (4263 words)

	Citebase - Bibliography of publications related to Classical and Quantum Gravity in terms of Connection and Loop ... (Site not responding. Last check: 2007-10-22)
		On the canonical quantization of gravity in the Ashtekar framework.
		Abhay Ashtekar, Viqar Husain, Carlo Rovelli, Joseph Samuel, and Lee Smolin.
		Ashtekar variables, the theta-term, and the cosmological constant.
	citebase.eprints.org /cgi-bin/citations?id=oai:arXiv.org:gr-qc/9703044 (1388 words)

	IGPG: News
		Abhay Ashtekar's profile was featured in the special issue of the GEO magazine on 100 Years of Relativity.
		Abhay Ashtekar was offered the Sir C.V. Raman Visiting Chair of the Indian Academy of Sciences (2004-05).
		Abhay Ashtekar was awarded a Senior Forschungspreis by the Alexander van Humboldt Foundation of Germany (2004-05).
	www.gravity.psu.edu /news.shtml (310 words)

	Citebase - On the Support of Physical Measures in Gauge Theories
		[5] Abhay Ashtekar and Chris J. Isham:Representations of the holonomy algebras of gravity and nonabelian gauge theories.
		[14] Abhay Ashtekar, Donald Marolf, José Mourao, and Thomas Thiemann:Constructing Hamiltonian quantum theories from path integrals in a diffeomorphism-invariant context.
		In the canonical quantization of gravity in terms of the Ashtekar variables one uses paths in the 3-space to construct the quantum states.
	citebase.eprints.org /cgi-bin/citations?archiveID=oai:arXiv.org:math-ph/0109030 (1625 words)

	Scrupulous intellectual honesty: The nature of time (Site not responding. Last check: 2007-10-22)
		I plain English, this means that you, Rovelli, Ashtekar, and many other physicists are ignoring a very old and widely known idea about the nature of time, namely, that the physical world is NOT sufficient for explaining the nature of time.
		Ashtekar are trying to 'isolate time' or 'bring time' into quantum gravity.
		Since 1986, the main hope of the Ashtekar approach is that it may yield solutions to its own analogue of the Wheeler-DeWitt equation.
	myweb.tiscali.co.uk /chakalov/Smolin.html (1103 words)

	PSU picked for new physics center
		With the help of the gravitational wave detectors located in Hanford, Wash., and Livingston, La., as well as two in Europe, Ashtekar is confident that researchers will soon capture their first glimpse of the phenomenon.
		Consisting of two identical four-kilometer arms set at 90-degree angles, these observatories incorporate interferometers that amplify the effect of gravitational waves using high power lasers in what is the biggest vacuum on Earth.
		Ashtekar believes the use of these waves will greatly improve our ability to observe space, opening a new window to the universe.
	www.collegian.psu.edu /archive/2001/10/10-30-01tdc/10-30-01dscihealth-2.asp (533 words)

	Area
		Abhay Ashtekar, John Baez, Alejandro Corichi and Kirill Krasnov, Quantum geometry and fl hole entropy.
		Abhay Ashtekar, Alejandro Corichi and Kirill Krasnov, Isolated horizons: the classical phase space.
		Abhay Ashtekar, John Baez, and Kirill Krasnov, Quantum geometry of isolated horizons and fl hole entropy.
	math.ucr.edu /home/baez/area.html (387 words)

	Rediff On The NeT: The Rediff Profile/ Dr Abhay Ashtekar
		Dr Ashtekar often goes back to India to visit family and for conferences, and was there last in December 1998.
		Although he is an atheist, Dr Ashtekar says, his attitude toward work is from the Hindu religious text, the Bhagavad Gita.
		Dr Ashtekar too admits that he is "never bored.
	inhome.rediff.com /news/1999/may/15us5.htm (726 words)

	Spin networks, spin foams and loop quantum gravity
		Ashtekar's "new" variables and the initial value formulation of GR John C. Baez and Javier P. Muniain.
		Abhay Ashtekar, Mathematical problems of non-perturbative quantum general relativity (lectures delivered at the 1992 Les Houches summer school on Gravitation and Quantization), 87 pages.
		C Rovelli, Ashtekar formulation of general relativity and loop space non-perturbative Quantum Gravity: a report, Classical and Quantum Gravity, 8, 1613-1675 (1991).
	jdc.math.uwo.ca /spin-foams (2348 words)

	waltf007 @ MindSay
		Abhay Ashtekar, the leader of a worldwide effort to unify the two most
		Abhay Ashtekar grew up in small cities in the Indian state of Maharastra, which
		Ashtekar and his colleagues were able to calculate the entropy for a fl hole,
	waltf007.mindsay.com (1912 words)

	week7
		Ashtekar's "new variables" - from this point of view - rely on a curious and profound fact about so(1,3).
		Ashtekar came up with some "new variables" for general relativity in the context of the Hamiltonian approach.
		The advantage of Ashtekar's new variables is that the simplify the form of the constraint equations one gets in the initial-value problem for general relativity.
	math.ucr.edu /home/baez/week7.html (1847 words)

	Abhay Ashtekar - Encyclopedia Glossary Meaning Explanation Abhay Ashtekar (Site not responding. Last check: 2007-10-22)
		Abhay Ashtekar - Encyclopedia Glossary Meaning Explanation Abhay Ashtekar.
		Here you will find more informations about Abhay Ashtekar.
		The orginal Abhay Ashtekar article can be editet
	www.encyclopedia-glossary.com /en/Abhay-Ashtekar.html (145 words)

	Science Journal -- Summer 2000 -- Faces of Penn State: Abhay Ashtekar (Site not responding. Last check: 2007-10-22)
		Since then, he has become a world-renowned physicist whose work has helped build a better understanding of the differing theories of general relativity and quantum mechanics.
		In a sense, the theory provides a means for examining how gravity might react as you examine smaller and smaller slices of space.
		In addition to quantum gravity, Ashtekar works problems related to very strong gravitational fields such as those encountered near the Big Bang.
	www.science.psu.edu /journal/Sum2000/AshtekarSum2000.htm (445 words)

	Re: Quantum gravity
		The key idea of Ashtekar was to use as basic variables, not the metric on S and its first time derivative, but the "chiral spin connection" on S and a "complex frame field".
		Essentially, Ashtekar's formalism seems at first to be better suited to general relativity with a complex-valued metric than to good old "real" general relativity.
		The first paper constructs a kind of transform that takes functions on the space of SU(2) connections on S into functions on the space of SL(2,C) connections on S. The "kinematical states" in Ashtekar's approach are, roughly speaking, functions of the latter kind.
	www.lns.cornell.edu /spr/1999-05/msg0016258.html (3757 words)

	Physics' Big Puzzle Has Big Question - What Is Time?
		Professor Wald was quick to add that the conference should not be seen as a desperate move by scientists to seek philosophical enlightenment on questions that have stymied the physicists.
		Abhay Ashtekar of Penn State, where he is director of the Center for Gravitational Physics and Geometry, conceded that "there is a little bit of shaking of confidence" among scientists thirsty for a breakthrough.
		But the symposium had a surprising ending when Professor Ashtekar, rather than one of the philosophers, turned to poetry for a note of hope.
	www.rense.com /general11/wahat.htm (1251 words)

	Physics Help and Math Help - Physics Forums - View Single Post - Time in Quantum Gravity (Site not responding. Last check: 2007-10-22)
		Something Abhay Ashtekar said is beginning to sink in.
		first note that in Ashtekar perspective, two of the four important avenues to explore are ones opened by Gambini et al.
		So this CD approach is quite new (first proposed by Gambini and Pullin in 2002) and looks promising---is appealing because obviates the constraint business---and it has a kind of "official Abhay stamp of approval" as being a good direction to look in.
	www.physicsforums.com /showpost.php?p=360839&postcount=36 (603 words)

	Strings Meet Loops (Site not responding. Last check: 2007-10-22)
		During October 29-31, 2003 the Albert-Einstein-Institute in Potsdam, Germany hosted the Symposium ``Strings Meet Loops'' which was organized by Abhay Ashtekar and Hermann Nicolai.
		The primary purpose was to bring together researchers working on string theory on the one hand, and on canonical and loop quantum gravity on the other, and to enhance the exchange of ideas between the two communities.
		Correspondingly, the program consisted of talks that were primarily addressed to the other community: four from string theorists (Kasper Peeters, Bernard de Wit, Michael Douglas and Jan Plefka) and four from the loop community (Abhay Ashtekar, Jurek Lewandowski, Martin Bojowald and Laurent Freidel).
	www.phys.lsu.edu /mog/mog23/node15.html (356 words)

	Abebooks Search Results - ... Abhay Ashtekar (Site not responding. Last check: 2007-10-22)
		Rodolfo Gambini, Jorge Pullin, Foreword by Abhay Ashtekar
		Revisiting the Foundations of Relativistic Physics (Boston Studies in the Philosophy of Science): Festschrift in Honor of John Stachel, Vol.
		Abhay Ashtekar (editor); R.S. Cohen (editor); Don Howard (editor); J. Renn (editor); S. Sarkar (editor); A. Shimony (editor)
	textbook-authors.abebooks.co.uk /Author/468011/...+Abhay+Ashtekar.html (573 words)

	Abhay Ashtekar ; Asymptotic Quantization Based on 1984 Naples Lectures Monographs and Textbooks in Physical Science ... (Site not responding. Last check: 2007-10-22)
		Abhay Ashtekar ; Asymptotic Quantization Based on 1984 Naples Lectures Monographs and Textbooks in Physical Science Lecture Notes Vol 2, Abigail Frost Frances Halton - American Indians [Myths and Legends],
		Abhay Ashtekar Ranjeet S Tate - Lectures on Non - Perturbative Canonical Gravity Advanced Series in Astrophysics and Cosmology Vol 6
		abhay abhai ashtecar ashtekar bhay ahay abay abhy abha abhayashtekar shtekar ahtekar astekar ashekar ashtkar ashtear ashtekr ashteka
	www.worldbiggestbookstore.com /1950_abhay-ashtekar.html (212 words)

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