Arquivos
A semana nos arXivs…
- A Brief Introduction to Wilson Loops and Large N. (arXiv:0906.4487v1 [hep-th])
- On the eigenvalues of the twisted Dirac operator
- Black holes, information, and decoherence
- Branes, instantons, and Taub-NUT spaces
- Fractional quantum Hall effect via holography: Chern-Simons, edge states and hierarchy
- Zeros of Airy Function and Relaxation Process. (arXiv:0906.3666v1 [math.PR])
- Constructive Field Theory in Zero Dimension. (arXiv:0906.3524v1 [math-ph])
- Quantum gravity as sum over spacetimes. (arXiv:0906.3947v1 [gr-qc]), In Search of Fundamental Discreteness in 2+1 Dimensional Quantum Gravity. (arXiv:0906.3547v1 [gr-qc])
- Prospects for constraining quantum gravity dispersion with near term observations. (arXiv:0906.3731v2 [astro-ph.HE])
- Monty Hall, Monty Fall, Monty Crawl
- This Week’s Finds in Mathematical Physics (Week 275)
- A force by any other name…
- Dyson’s stance on climate change: excelente entrevista, contendo mais detalhes e contextualizando apropriadamente a postura do Dyson — e olha que ele nem falou nada sobre plânctons, algas e recifes (e metano)!
- Increasingly Popular Research Yields Increasingly Unreliable Results
- Melhores machos têm menos filhos ou Good males are bad fathers
- Is Science Journalism Breaking the Convention? e The Priesthood of Science Journalism
- Splish! Splash! Hydrotherapy for chronic back pain is pretty good!
- Opinion: Invest in UK science says Martin Rees
- Editors in Web2.0
- Hide files in an image
- Conference Networking e Networking Tips for the Introverted
- [Editorial] Science Journalism Goes Global
- Science can bridge national divides | David Kerr, Are we witnessing the end of science? | Ehsan Masood
- Quantum Mechanics Visible In Everyday Life?
- O papel da universidade, artigo de Gil da Costa Marques
- Fair Research Assessments Require Extensive Deliberation, On article-level metrics and other animals, Impact Factor Boxing 2009
- 7 Man-Made Substances that Laugh in the Face of Physics
- Ciência em ação e Apoio inédito a pesquisa
A semana nos arXivs…
- Sturm-Liouville Theory and Orthogonal Functions. (arXiv:0906.3209v2 [math.CA])
- Quantum Gravity, Field Theory and Signatures of Noncommutative Spacetime. (arXiv:0906.2913v1 [hep-th])
- Non-Hamiltonian Actions and Lie-Algebra Cohomology of Vector Fields. (arXiv:0906.2988v1 [math.DG])
- Ordinary differential and difference equations invariant under SL(2,R) and their solutions. (arXiv:0906.2980v1 [math-ph])
- Gauge Theory and Langlands Duality
- Quantum entanglement
- Synchronicity
- Akulov-Volkov Redux
- UK backs off using citations to judge research quality
- US scholars have less time for research says survey
- The science of talking so people want to listen
- Lies, damned lies, and scientific misconduct
- Reclaim The Commons: A Manifesto
- Backup and fault tolerance in systems biology: Striking similarity with Cloud computing
- Metaphors in systems biology-A grid of super-computers
- THE SIMPLIFIER: A Conversation with John A. Bargh
- A narrower Atlantic
- Elsevier Does a Microsoft with Open Access
- Inteligência nacional
- Lei de Inovação de São Paulo será regulamentada em breve
- Opinion: Should Fortran be taught to undergraduates?
- Professional Polish
- Tai Chi Can Help With Arthritis Pain – Study
- How Gamers Helped Science
- Aviary Launches Falcon, A Browser Based Image Editor
A semana nos arXivs…
- Five Problems in Quantum Gravity. (arXiv:0906.1313v1 [hep-th])
- Generalized Kahler geometry, gerbes, and all that. (arXiv:0906.1056v1 [math.SG])
- Gauge conservation laws in a general setting. Superpotential. (arXiv:0906.1732v1 [math-ph])
- Stochastic Quantization of the Horava Gravity. (arXiv:0906.1645v1 [hep-th])
- The QCD beta-function from global solutions to Dyson-Schwinger equations. (arXiv:0906.1754v1 [hep-th])
- Algebra for quantum fields. (arXiv:0906.1851v1 [hep-th])
- Regularization in quantum field theory from the causal point of view. (arXiv:0906.1952v1 [hep-th])
- Remarks on the world-sheet saga. (arXiv:0906.2067v1 [physics.gen-ph])
- String Universality in Six Dimensions. (arXiv:0906.0987v2 [hep-th])
- The light-cone theorem
- Cosmology’s golden age
- Nonabelian Algebraic Topology
- Google Translator Kit: Automated Translation Meets Crowdsourcing
- The Last 100 Years: 1919, Einstein and Eddington [Starts With A Bang]
- The Wrong Level of Abstraction
- Chaos [Good Math, Bad Math], Defining Dynamical Systems [Good Math, Bad Math]
- Google Scholar – really scholarly?
- Unix is Dead, Long Live Unix
A semana nos arXivs…
- Orientifold Precis. (arXiv:0906.0795v1 [hep-th])
- Functional integral representations for self-avoiding walk. (arXiv:0906.0922v1 [math.PR])
- FJRW rings and Landau-Ginzburg Mirror Symmetry. (arXiv:0906.0796v1 [math.AG])
- String field theory-inspired algebraic structures in gauge theories
- More is the Same; Phase Transitions and Mean Field Theories. (arXiv:0906.0653v1 [physics.hist-ph])
- Expansions for Eigenfunction and Eigenvalues of large-n Toeplitz Matrices. (arXiv:0906.0760v1 [math-ph])
- The Bernstein Conjecture, Minimal Cones, and Critical Dimensions. (arXiv:0906.0264v1 [hep-th])
- Science in a Very Large Universe. (arXiv:0906.0042v1 [hep-th])
- Conformality Lost. (arXiv:0905.4752v1 [hep-th])
- Geometric Langlands And The Equations Of Nahm And Bogomolny. (arXiv:0905.4795v1 [hep-th])
- Black holes in full quantum gravity. (arXiv:0905.4916v1 [gr-qc])
- Breaking the dark force
- Signs of a critical point
- Cohomology for amateurs — by an amateur
- The infinitesimal site
- What string theory is really good for
- The Elusive Proteus
- Gender, culture, and mathematics performance
- Berners-Lee: We no longer fully understand the web
- Don’t panic
- Economia Politica do Intelectual
- De volta ao problema do Apartheid racial: o problema das cotas
- Brain Thermodynamics
- A rape in progress, Part II
- The Mathematics of Music at Chicago
- Turtles
- Oprah is a crank [denialism blog]
- A Tale of Two Slits [Starts With A Bang]
- The Girl Who Proved ‘P = NP’
- Create presentations that inspire
A semana nos arXivs…
- Geometric Langlands From Six Dimensions. (arXiv:0905.2720v1 [hep-th])
- Probing Geometry with Stability Conditions. (arXiv:0905.3137v1 [hep-th])
- Fractal Quantum Space-Time. (arXiv:0905.1665v1 [gr-qc])
- There is no “Theory of Everything” inside E8. (arXiv:0905.2658v1 [math.RT]) (esse é especial pra quem se hipnotizou pela An Exceptionally Simple Theory of Everything )
- Replication Regulates Volume Weighting in Quantum Cosmology. (arXiv:0905.3877v1 [hep-th])
- A critical look at 50 years particle theory from the perspective of the crossing property. (arXiv:0905.4006v1 [hep-th])
- QJT as a Regularization: Origin of the New Gauge Anomalies. (arXiv:0905.4043v1 [hep-th])
- BMS symmetry, holography on null-surfaces and area proportionality of “light-slice” entropy. (arXiv:0905.4435v1 [hep-th])
- Massless spacetime: On spacetime geometry above the electroweak symmetry breaking scale. (arXiv:0905.4547v1 [gr-qc])
- Particle decay in de Sitter spacetime via quantum tunneling. (arXiv:0905.4639v1 [gr-qc])
- The Order of Sir Bondi. (arXiv:0905.3218v2 [physics.hist-ph])
- Categories for the practising physicist. (arXiv:0905.3010v1 [quant-ph])
- The Mathematical Structure of the Quantum BRST Constraint Method. (arXiv:0905.3570v2 [math.OA])
- On incompleteness of classical field theory. (arXiv:0905.3912v1 [math-ph])
- Pathwise Accuracy and Ergodicity of Metropolized Integrators for SDEs. (arXiv:0905.4218v1 [math.NA])
- Quantum Probability, Renormalization and Infinite-Dimensional *-Lie Algebras. (arXiv:0905.4491v1 [math-ph])
- Complementarity between private and public investment in R&D: A Dynamic Panel Data analysis. (arXiv:0905.4272v1 [q-fin.ST])
- Comparing topological charge definitions using topology fixing actions. (arXiv:0905.2849v1 [hep-lat])
- Quantum Field Theories on Algebraic Curves and A. Weil Reciprocity Law. (arXiv:0812.0169v2 [math.AG])
- Critical phenomena: 150 years since Cagniard de la Tour. (arXiv:0905.1886v1 [physics.hist-ph])
- Summing over all Topologies in CDT String Field Theory. (arXiv:0905.2108v2 [hep-th])
- Hitchin’s Equations and M-Theory Phenomenology. (arXiv:0905.1968v1 [hep-th])
- Can quantum mechanics fool the cosmic censor?
- Fractal Dimension in 3d Spin-Foams. (arXiv:0905.2170v1 [gr-qc])
- The light-cone theorem. (arXiv:0905.2133v1 [gr-qc])
- Structure, classifcation, and conformal symmetry, of elementary particles over non-archimedean space-time. (arXiv:0905.1217v1 [math-ph])
- Glimmers of a connection between string theory and atomic physics
- Doing sums with swirls
- Holonomy and parallel transport in the differential geometry of loop spaces and generalized gauge transformations
- Statistical physics of social dynamics
- Topological Quantum Field Theories from Compact Lie Groups. (arXiv:0905.0731v1 [math.AT])
- Universal Constants, Standard Models and Fundamental Metrology. (arXiv:0905.0975v1 [hep-th])
- Grassroots Science: An Article Wishlist For The Journal of Scientific Communication
- SCIENCE PUBLISHING: Fabrication and Falsification are Widespread in Science
- Brilliant Father Teaches His Children to Argue With Him Using Ancient Greek Rhetoric
- Workshop on tests of gravity in Case Western – day 2 and Arkani-Hamed’s talk (é incrível como esses argumentso diretos e extremamente “físicos” feitos pelo Nima costumam passar largamente desapercebidos pela caravana que passa…)
- Particle Physics – Not Just For Black Holes And Blowing Up The Vatican Any More (aliás, achei o filme bem fraquinho… não sei se estou ficando velho, mas acho que estou ficando mais chato… nas cenas onde se fala do LHC e de antimatéria, eu realmente fiquei ‘tenso’
) - Andes, an intelligent homework helper for physics. Written in Common Lisp
- New introduction: Getting something out of LaTeX
- Scientific Software Wants To Be Free
- The Crisis and How to Deal with It
- Asymptote released on CTAN
- Square roots with pencil and paper: the Babylonian method
- Japanese government to pay industry to hire postdocs
- Why Do Computers Suck at Math?, The Web Browser Address Bar is the New Command Line
A semana nos arXivs…
- Conformal field theory and Loewner-Kufarev evolution. (arXiv:0905.0813v1 [math-ph]) — quem quiser saber mais sobre esse assunto, eu recomendo fortemente o seguinte artigo, Conformal invariance and
statistical physics
- Twisted Deformation Quantization of Algebraic Varieties (atendendo a pedidos…
) - Gauge field theories with covariant star-product. (arXiv:0905.0608v1 [hep-th])
- Horava-Lifshitz Holography. (arXiv:0905.0473v1 [hep-th])
- The Inner Brane. (arXiv:0905.0540v1 [hep-th])
- Gromov-Witten Gauge Theory I. (arXiv:0904.4834v1 [math.AG])
- A causal perspective on random geometry. (arXiv:0905.0213v1 [hep-th])
- There are no conformal Einstein rescalings of complete pseudo-Riemannian Einstein metrics. (arXiv:0905.0262v1 [math.DG])
- From time to causality. (arXiv:0905.0274v1 [gr-qc])
- The quantization of unimodular gravity and the cosmological constant problem. (arXiv:0904.4841v1 [hep-th])
- Local systems: the infinitesimal perspective
- Statistical Physics of Particles, Statistical Physics of Fields
- The stuff you can do with accelerators
- Can Numerical Modeling Match The Needs Of Science?
- For China, a reverse brain drain in science?
- Are We Beyond the Two Cultures? — lembrando, sempre que nós podemos muito bem caminhar em direção à Terceira Cultura!
- Making It, Malcolm Gladwell: When underdogs break the rules
- The scientist who foresaw the financial crash
- Cresce apoio de empresa à pesquisa
- ‘Problema do ensino não passa pelas cotas’, avalia sociólogo
- Dog Aggression: Its not the breed, its the human
- “To learn, you must pay attention.” Molecular insights into teachers’ wisdom
- Science 2.0: what is and what needs to be
- Edwin Hubble: Astronomer And … Champion Basketball Player?
- Pentagon Lost Billions, Pennies At a Time
A semana nos arXivs…
- The Second Law and Cosmology (arXiv:0904.3931v1 [physics.pop-ph]); Eu recomendo fortemente que, aqueles que quiserem ler esse artigo, o façam em paralelo aos comentários do Penrose em “The Road to Reality“, Capítulo 27.
- p-Adic Mathematical Physics. (arXiv:0904.4205v1 [math-ph])
- An approach to a theory of quantum gravity (discussão sobre esse artigo nos ‘comentários’ abaixo)
- Thermal Vacuum Radiation in Spontaneously Broken Second-Quantized Theories on Curved Phase Spaces of Constant Curvature. (arXiv:0904.3814v1 [hep-th])
- Quantum fields on curved spacetimes and a new look at the Unruh effect. (arXiv:0904.3751v1 [hep-th]) mais-ou-menos comentado em Some musings about Unruh effect
- Seiberg-Witten equations from Fedosov deformation quantization of endomorphism bundle. (arXiv:0904.4409v1 [hep-th])
- Local systems: the path groupoid approach
- Three ways of looking at a local system: Introduction and connection to cohomology theories: ver também Matthew Emerton is smart and helpful.
- The Earth – For Physicists
- The most influential journals: Impact Factor and Eigenfactor
- The White House – Press Office – Remarks by the President at the National Academy of Sciences Annual Meeting: a diferença que faz um “Plano de Nação” (de 50 anos!) para um país.
- Europe Funds Secure Operating System Research: pra quem não conhece, eu recomendo se familiarizar com a história do projeto GNU, Free Software, do kernel do Linus — que foi baseado no
minix—, e assim por diante… só pra por tudo isso em perspectiva
- Drinking tea with the LHC
A semana nos arXivs…
- Spectral Dimension of the Universe in Quantum Gravity at a Lifshitz Point
- Diffeomorphism covariant star products and noncommutative gravity. (arXiv:0904.3079v1 [hep-th])
- Rethinking Renormalization. (arXiv:0904.2869v1 [hep-th])
- Dynamical compactification from de Sitter space. (arXiv:0904.3115v1 [hep-th])
A semana nos arXivs…
- Symmetry Breaking: A New Paradigm for Non-Perturbative QFT and Topological Transitions. (arXiv:0904.2205v1 [hep-th])
- Symmetric space Cartan connections and gravity in three and four dimensions. (arXiv:0904.1738v1 [math.DG])
- Large matrices and Virasoro Conjecture. (arXiv:0904.1916v1 [math-ph])
- An exploration of CUDA and CBEA for a gravitational wave data-analysis application (Einstein@Home). (arXiv:0904.1826v1 [gr-qc])
- ħ as parameter of Minkowski metric in effective theory. (arXiv:0904.1965v1 [gr-qc])
- Fermions and the AdS/CFT correspondence: quantum phase transitions and the emergent Fermi-liquid. (arXiv:0904.1993v1 [hep-th])
- Lectures on Holographic Superfluidity and Superconductivity. (arXiv:0904.1975v1 [hep-th])
- Approach to equilibrium for a class of random quantum models of infinite range. (arXiv:0904.2130v1 [math-ph])
- Doves and hawks in economics revisited. An evolutionary quantum game theory-based analysis of financial crises. (arXiv:0904.2113v1 [nlin.AO])
- Could it be? Science critics calls for a truce
- Lost in the Maelstrom: Revisisting the ‘Two Cultures’
- Scientific Progress as Black Swans
- “I’ll Never Use The Skills I Learned In Physics”
- Murray Gell-Mann, the physicist who found quarks and made sense of the universe
- Dyson as Sociologist? Death Trains, Values, & Climate Action
A semana nos arXivs…
- The Algebra of Grand Unified Theories. (arXiv:0904.1556v1 [hep-th])
- The Scientific Contributions of Joel Scherk. (arXiv:0904.0537v1 [hep-th])
- String theory and the Kauffman polynomial. (arXiv:0904.1088v1 [hep-th])
- Fortran MPI Checkerboard Code for SU(3) Lattice Gauge Theory I ,Fortran MPI Checkerboard Code for SU(3) Lattice Gauge Theory II. (arXiv:0904.1179v1 [hep-lat])
- Geometry and triply graded knot homology
- The strange history of Paul Dirac
- Inside the tangled world of string theory
- The physics of pizza tossing
- Physics of Socio-Economic Systems: Soccer
- Collaborating and Co-Authoring
- Howard Burton: First Principles, First Principles
- In Math Education, Concepts Are Better Than Specific Procedures
- Brasil gasta mais com “spread” do que com saúde e educação (e aposto que também se pode jogar a “Ciência e Tecnologia” nessa lista
) - Miseria da educacao no Brasil
- Articulista do Wall Street Journal discorre sobre o IBAS
- What is FriendFeed? And why it’s better than ever
A semana nos arXivs…
- Some surprising implications of background independence in canonical quantum gravity. (arXiv:0904.0184v1 [gr-qc])
- Geometric and deformation quantization. (arXiv:0903.5336v1 [math-ph])
- Algebras of unbounded operators and physical applications: a survey. (arXiv:0903.5446v1 [math-ph])
- Exact lattice supersymmetry. (arXiv:0903.4881v1 [hep-lat])
- Unpublished opening lecture for the course on the theory of relativity in Argentina, 1925. (arXiv:0903.2401v1 [physics.hist-ph])
- Einstein’s unpublished opening lecture for his course on relativity theory in Argentina, 1925. (arXiv:0903.2064v1 [physics.hist-ph])
- Quantum field theory on a cosmological, quantum space-time
- The Algebra of Grand Unified Theories III
- Latest Langlands
- Some facts about time to the PhD
- Mikhail Gromov wins 2009 Abel prize
- ‘Educating Global Citizens’
- In search of the black swans
- Making physics popular
- Could A Publish Or Perish Attitude Produce Einstein Today?
- Fermi problems
- Scientists observe largest supernova yet seen from start to finish, including the black hole ending
A semana nos arXivs…
- Emergent non-commutative matter fields from Group Field Theory models of quantum spacetime. (arXiv:0903.3970v1 [hep-th])
- Program package for multicanonical simulations of U(1) lattice gauge theory. (arXiv:0903.3984v1 [hep-lat])
- Quantum geometry from phase space reduction. (arXiv:0902.0351v3 [gr-qc])
- On the interplay between Lorentzian Causality and Finsler metrics of Randers type. (arXiv:0903.3501v1 [math.DG])
- Morse theory of causal geodesics in a stationary spacetime via Morse theory of geodesics of a Finsler metric. (arXiv:0903.3519v1 [math.DG])
- “Forget time”. (arXiv:0903.3832v2 [gr-qc])
- Physics and Complexity.
- Leaping into the Grand Unknown — leiam mais sobre Freeman Dyson nessa reportagem do NYT, The Civil Heretic.
- Sailing into the wind, or faster than the wind.
- The global economic crisis isn’t about money — it’s about power. How Wall Street insiders are using the bailout to stage a revolution.
- Black days for those dreaming of the ivory tower.
- Science, journalism and other sports.
A semana nos arXivs…
- Recursive relations in the core Hopf algebra. (arXiv:0903.2849v1 [hep-th])
- Relativistic invariance of Lyapunov exponents in bounded and unbounded systems. (arXiv:0903.2296v1 [nlin.CD])
- Black holes, information and decoherence. (arXiv:0903.2258v1 [gr-qc])
- Quantum cosmic censor: gravitation makes reality undecidable. (arXiv:0903.2438v1 [gr-qc])
- Introduction to the Gopakumar-Vafa Large N Duality. (arXiv:math/0701568v2 [math.GT])
- Globalization and human cooperation
- Decentralization for cost-effective conservation
- The Algebra of Grand Unified Theories II
- A Scientific Approach to Science Education – Research On Learning (Why Not Try A Scientific Approach To Science Education?)
A semana nos arXivs…
-
The Volume Conjecture and Topological Strings. (arXiv:0903.2084v1 [hep-th])
-
Particle Topology, Braids, and Braided Belts. (arXiv:0903.1376v1 [math.AT])
-
Birkhoff’s invariant and Thorne’s Hoop Conjecture. (arXiv:0903.1580v1 [gr-qc])
see more Lolcats and funny pictures
Se vc, de fato, fizer isso, o que realmente acontece é que Douglas Hofstadter aparece e fica falando por 8 horas sobre laços e recurssão.
A semana nos arXivs…
- Digital Ecosystems in the Clouds: Towards Community Cloud Computing
- Relating Field Theories via Stochastic Quantization
- Living with Infinities
- Spin Foam Quantization and Anomalies
- Anomalies in Quantum Field Theory and Cohomologies of Configuration Spaces
- Physics, Topology, Logic and Computation: A Rosetta Stone
- Noether symmetries, energy-momentum tensors and conformal invariance in classical field theory
- Alternatives to Cosmological Inflation
- Exact Lattice Supersymmetry
- Super-Yang-Mills Theory
- Random matrices: The distribution of the smallest singular values
- Lurie on TQFT and the Cobordism Hypothesis
- Two-slit diffraction with highly charged particles: Niels Bohr’s consistency argument that the electromagnetic field must be quantized
- Dodging the crisis of folding proteins with knots
- Scaling and self-organized criticality in proteins I
- Scaling and self-organized criticality in proteins II
- Generalized Eigenspaces are Disjoint
- Tricks Wiki: Give yourself an epsilon of room (será que alguém disse mollifier? )
- Is There a Higgs? (só para uma diversão-zinha, God particle: Portrait of Peter Higgs unveiled e Fermilab and the search for the Higgs Boson)
- What’s the big idea?
- A noble conception
- A quantum of natural selection
- Quantum Darwinism
- Drought Sensitivity of the Amazon Rainforest
- UNION OF CONCERNED SCIENTISTS: From Protest to Power: An Advocacy Group Turns 40
- U.S. BUDGET: Budgets in Brief
- U.S. BUDGET: Amid the Gloom, Researchers Prepare for a Boom in Funding
- Do science jobs make the best careers?
- Capitalism Beyond the Crisis, por Amartya Sen
- A handy guide to grids and clouds
- A fool and his money are soon parted
- Reframing Human Rights in the Global Era: A tribute to Sergio Vieira de Mello
- Cuba Gets an (Open) Hand from Brazil
- 26 New and Awesome Web Apps You Probably Don’t Know About
Quero fazer uns comentários sobre o artigo/entrevista (“Is There a Higgs”) do Brain Cox acima… continue lendo…
A semana nos arXivs…
Depois de uma semaninha fraquinha… algumas coisas bem interessantes estão aparecendo pelos arXivs está semana…
- Energy loss in a strongly coupled thermal medium and the gauge-string duality
- Emergent Calabi-Yau Geometry
- Holonomy Loops, Spectral Triples & Quantum Gravity
- Spectral Dimension of the Universe in Quantum Gravity at a Lifshitz Point
- The Superspace of Geometrodynamics
- Group field theory and simplicial quantum gravity
- Toeplitz Quantization and Asymptotic Expansions: Geometric Construction
- Sky’s the limit for sand dunes
- String theory deconstructed
- String theory, the crisis in particle physics and the ascent of metaphoric arguments
- PNAS: Overcoming systemic roadblocks to sustainability: The evolutionary redesign of worldviews, institutions, and technologies
- Beautiful differentiation: a precise, efficient, and convenient method for computing derivatives of functions
- R&D a must for America’s future
- Travel Efficiency
- Critical Thinking Skills — The Cure for Anti-Intellectualism
- Politics in the Guise of Pure Science
- Open Science: Good for Research and Researchers
- The Economy According to MC Escher e The Credit Crisis Visualized
- Calculating The Ideologies Of Powerful Think Tanks
- Why Did Ice In Antarctica Suddenly Appear 35 Million Years Ago? CO2, Says Study
- PacMobius e Torus Explained e PakleinMan (só porque eu falei que seria menos previsível ver um “PacMan Escheriano” do que um “Kleiniano”… claro, saiu o Kleiniano )
- PHD comic: ‘How to turn your CV into a Resume’
Fluxo de Ricci, Flutuações Quânticas e Geometria…
Já faz algum tempo que eu quero escrever sobre esse assunto: flutuações quânticas, fluxo de Ricci, geometria, fluxo do grupo de renormalização e afins. Agora parece ser o momento certo…
De saída, digo que todas as estruturas matemáticas ou físicas possuem as propriedades necessárias pros resultados citados valerem, FAPP. Assim, isso economiza uma série de “observações” que deveriam ser feitas… mas, facilita um tanto a visão geral e o objetivo das construções feitas.
Introdução
Vamos começar definindo um básico de notação: 
![\mbox{Act}[\mbox{Map}(\Sigma,\mathscr{M})\times \mathcal{C}]](http://s0.wp.com/latex.php?latex=%5Cmbox%7BAct%7D%5B%5Cmbox%7BMap%7D%28%5CSigma%2C%5Cmathscr%7BM%7D%29%5Ctimes+%5Cmathcal%7BC%7D%5D&bg=ffffff&fg=555555&s=0 "\mbox{Act}[\mbox{Map}(\Sigma,\mathscr{M})\times \mathcal{C}]")
![S[\phi;\alpha]](http://s0.wp.com/latex.php?latex=S%5B%5Cphi%3B%5Calpha%5D&bg=ffffff&fg=555555&s=0 "S[\phi;\alpha]")
![S[\phi;\alpha] \in\mathbb{R}](http://s0.wp.com/latex.php?latex=S%5B%5Cphi%3B%5Calpha%5D+%5Cin%5Cmathbb%7BR%7D&bg=ffffff&fg=555555&s=0 "S[\phi;\alpha] \in\mathbb{R}")
Vamos agora nos lembar que uma QFT (Euclidiana) é totalmente determinada por suas Funções de Green, i.e., pelas correlações induzidas por uma família de densidade de probabilidades (i.e., medidas) em 
![Z[\phi(x_k);\alpha] \equiv \displaystyle\int_{\mbox{Map}(\Sigma,\mathscr{M})} \phi(x_1,\dotsc,x_k)\, e^{-S[\phi;\alpha]}\, D_{\alpha}[\phi] \; ;](http://s0.wp.com/latex.php?latex=Z%5B%5Cphi%28x_k%29%3B%5Calpha%5D+%5Cequiv+%5Cdisplaystyle%5Cint_%7B%5Cmbox%7BMap%7D%28%5CSigma%2C%5Cmathscr%7BM%7D%29%7D+%5Cphi%28x_1%2C%5Cdotsc%2Cx_k%29%5C%2C+e%5E%7B-S%5B%5Cphi%3B%5Calpha%5D%7D%5C%2C+D_%7B%5Calpha%7D%5B%5Cphi%5D+%5C%3B+%3B&bg=ffffff&fg=555555&s=0 "Z[\phi(x_k);\alpha] \equiv \displaystyle\int_{\mbox{Map}(\Sigma,\mathscr{M})} \phi(x_1,\dotsc,x_k)\, e^{-S[\phi;\alpha]}\, D_{\alpha}[\phi] \; ;")
onde ![D_{\alpha}[\phi]](http://s0.wp.com/latex.php?latex=D_%7B%5Calpha%7D%5B%5Cphi%5D&bg=ffffff&fg=555555&s=0 "D_{\alpha}[\phi]")
Dando uma interpretação geométrica ao cenário acima, mesmo no caso 0-dimensional nós já temos resultados não-triviais, onde 
)
Agora um “truque” que eu praticamente não vejo sendo usado: ao invés de se usar 
) Ou seja, se fizermos 
).
Falando em termos de 1-dim QFTs, temos explicitamente a Mecânica Quântica, que não passa de 
), eu recomendo a leitura do livro Quantum Fluctuations do Nelson.
Geometricamente falando, pode se dizer que no caso de QFT 1-dim (Euclidiana), a Função de Partição “sente” como as flutuações [quânticas] afetam os caminhos aleatórios 
(Aposto como agora fica mais fácil de se entender a importância da Métrica de Jacobi, usada em arXiv:0809.2778, para transformar um fluxo Hamiltoniano num fluxo geodésico. )
O Fluxo do Grupo de Renormalização
Os exemplos acima lidam com situações onde as flutuações quânticas podem ser usadas pra medir diferentes aspectos da geometria de 
Para atacar tal pergunta, é necessário “controlarmos” tanto os campos, 
)
Ou seja, é preciso reconhecermos duma vez por todas — e logo de saída! — que um dos ingredientes básicos de qualquer QFT é uma escala de energias. Há vários modos diferentes de se ver isso; e.g., em termos de Wilson Loops, isso está relacionado ao tamanho da curva 
), isso tem a ver com as variáveis de bloco escolhidas pra teoria (i.e., com o tamanho dos blocos); falando em termos de OPEs, significa escolher a álgebra de operadores de vértice (VOA) que codifica o comportamento da teoria numa dada escala de energia (i.e., ela codifica as propriedades importantes dum particular complemento ultra-violeta); e, finalmente, alguém pode gritar, lá do fundão: “Grupo de Renormalização”. 
Ou seja, determinar as holonomias da teoria, ou as variáveis de bloco ou o [particular] fluxo do grupo de renormalização (que se deseja tratar no caso em mãos), é tudo a mesma coisa.
Ou seja, é fundamental procurarmos por um conjunto de transformações (fluxo do grupo de renormalização) tais que,
Assim, quando variamos a escala 
Portanto, se temos duas escalas, 
![S'[\phi';\alpha'] = \mbox{RG}_{\Lambda\rightarrow\Lambda'} S[\phi;\alpha] \; .](http://s0.wp.com/latex.php?latex=S%27%5B%5Cphi%27%3B%5Calpha%27%5D+%3D+%5Cmbox%7BRG%7D_%7B%5CLambda%5Crightarrow%5CLambda%27%7D+S%5B%5Cphi%3B%5Calpha%5D+%5C%3B+.&bg=ffffff&fg=555555&s=0 "S'[\phi';\alpha'] = \mbox{RG}_{\Lambda\rightarrow\Lambda'} S[\phi;\alpha] \; .")
Essa é a essência das Teorias Efetivas (ver também Grupo de Renormalização).
Porém, pra que essa construção seja possível, é preciso que o mapa 
ou seja, é possível se fluir um sistema (no sentido do grupo de renormalização) apenas na direção de altas energias (resp. pequenas distâncias) para baixas energias (resp. grandes distâncias).
Falando em termos geométricos, uma QFT é caracterizada por uma ação ![e^{-S[\phi;\alpha]}\, D_{\alpha}[\phi]](http://s0.wp.com/latex.php?latex=e%5E%7B-S%5B%5Cphi%3B%5Calpha%5D%7D%5C%2C+D_%7B%5Calpha%7D%5B%5Cphi%5D&bg=ffffff&fg=555555&s=0 "e^{-S[\phi;\alpha]}\, D_{\alpha}[\phi]")
![\displaystyle\int_{\mbox{RG}_{\ell}\{\mbox{Map}(\Sigma,\mathscr{M})\}} \exp\{-S[\phi;\alpha]\}\, D_{\alpha}[\phi] = \displaystyle\int_{\mbox{Map}(\Sigma,\mathscr{M})} \exp\{-\mbox{RG}_{\ell}^{*}(S[\phi;\alpha])\}\, \mbox{RG}_{\ell}^{*}\bigl(D_{\alpha}[\phi]\bigr) \; ;](http://s0.wp.com/latex.php?latex=%5Cdisplaystyle%5Cint_%7B%5Cmbox%7BRG%7D_%7B%5Cell%7D%5C%7B%5Cmbox%7BMap%7D%28%5CSigma%2C%5Cmathscr%7BM%7D%29%5C%7D%7D+%5Cexp%5C%7B-S%5B%5Cphi%3B%5Calpha%5D%5C%7D%5C%2C+D_%7B%5Calpha%7D%5B%5Cphi%5D+%3D+%5Cdisplaystyle%5Cint_%7B%5Cmbox%7BMap%7D%28%5CSigma%2C%5Cmathscr%7BM%7D%29%7D+%5Cexp%5C%7B-%5Cmbox%7BRG%7D_%7B%5Cell%7D%5E%7B%2A%7D%28S%5B%5Cphi%3B%5Calpha%5D%29%5C%7D%5C%2C+%5Cmbox%7BRG%7D_%7B%5Cell%7D%5E%7B%2A%7D%5Cbigl%28D_%7B%5Calpha%7D%5B%5Cphi%5D%5Cbigr%29+%5C%3B+%3B&bg=ffffff&fg=555555&s=0 "\displaystyle\int_{\mbox{RG}_{\ell}\{\mbox{Map}(\Sigma,\mathscr{M})\}} \exp\{-S[\phi;\alpha]\}\, D_{\alpha}[\phi] = \displaystyle\int_{\mbox{Map}(\Sigma,\mathscr{M})} \exp\{-\mbox{RG}_{\ell}^{*}(S[\phi;\alpha])\}\, \mbox{RG}_{\ell}^{*}\bigl(D_{\alpha}[\phi]\bigr) \; ;")
de forma que essa igualdade seja válida no limite 
É importante, porém, sempre se lembrar que 
De qualquer maneira, quando é possível se fazer tal construção, a equação acima diz que existe um espaço limite, 
), de objetos geométricos que descrevem a QFT em mãos — tipicamente, esses objetos não pertencem ao espaço original, 
), uma vez que o fluxo de 
Para discutir esse tipo de questão, vamos tomar a Função de Partição como sendo,
![Z[\phi_{\Lambda}; \alpha(\Lambda)] \equiv \displaystyle\int_{\mbox{Map}(\Sigma, \mathscr{M})} \exp\bigl\{-\mbox{RG}_{\Lambda}^{*}(S[\phi;\alpha])\bigr\}\, \mbox{RG}_{\Lambda}^{*}\bigl(D_{\alpha}[\phi]\bigr) \; ;](http://s0.wp.com/latex.php?latex=Z%5B%5Cphi_%7B%5CLambda%7D%3B+%5Calpha%28%5CLambda%29%5D+%5Cequiv+%5Cdisplaystyle%5Cint_%7B%5Cmbox%7BMap%7D%28%5CSigma%2C+%5Cmathscr%7BM%7D%29%7D+%5Cexp%5Cbigl%5C%7B-%5Cmbox%7BRG%7D_%7B%5CLambda%7D%5E%7B%2A%7D%28S%5B%5Cphi%3B%5Calpha%5D%29%5Cbigr%5C%7D%5C%2C+%5Cmbox%7BRG%7D_%7B%5CLambda%7D%5E%7B%2A%7D%5Cbigl%28D_%7B%5Calpha%7D%5B%5Cphi%5D%5Cbigr%29+%5C%3B+%3B&bg=ffffff&fg=555555&s=0 "Z[\phi_{\Lambda}; \alpha(\Lambda)] \equiv \displaystyle\int_{\mbox{Map}(\Sigma, \mathscr{M})} \exp\bigl\{-\mbox{RG}_{\Lambda}^{*}(S[\phi;\alpha])\bigr\}\, \mbox{RG}_{\Lambda}^{*}\bigl(D_{\alpha}[\phi]\bigr) \; ;")
e reescrever a relação anterior em sua forma diferencial,
![\displaystyle\frac{d}{d\Lambda} Z[\phi_{\Lambda}; \alpha(\Lambda)] = \biggl\{\displaystyle\frac{\partial}{\partial\Lambda} - \beta(\alpha(\Lambda))\, \displaystyle\frac{\partial}{\partial \alpha}\biggr\}\, Z[\phi_{\Lambda}; \alpha(\Lambda)] = 0 \; ;](http://s0.wp.com/latex.php?latex=%5Cdisplaystyle%5Cfrac%7Bd%7D%7Bd%5CLambda%7D+Z%5B%5Cphi_%7B%5CLambda%7D%3B+%5Calpha%28%5CLambda%29%5D+%3D+%5Cbiggl%5C%7B%5Cdisplaystyle%5Cfrac%7B%5Cpartial%7D%7B%5Cpartial%5CLambda%7D+-+%5Cbeta%28%5Calpha%28%5CLambda%29%29%5C%2C+%5Cdisplaystyle%5Cfrac%7B%5Cpartial%7D%7B%5Cpartial+%5Calpha%7D%5Cbiggr%5C%7D%5C%2C+Z%5B%5Cphi_%7B%5CLambda%7D%3B+%5Calpha%28%5CLambda%29%5D+%3D+0+%5C%3B+%3B&bg=ffffff&fg=555555&s=0 "\displaystyle\frac{d}{d\Lambda} Z[\phi_{\Lambda}; \alpha(\Lambda)] = \biggl\{\displaystyle\frac{\partial}{\partial\Lambda} - \beta(\alpha(\Lambda))\, \displaystyle\frac{\partial}{\partial \alpha}\biggr\}\, Z[\phi_{\Lambda}; \alpha(\Lambda)] = 0 \; ;")
onde 
Como vcs vêm, a função β pode ser considerada como um campo vetorial (linhas de fluxo) no espaço de parâmetros, 
—, principalmente como feito no artigo Dimensional Analysis in field theory, devidamente comentado em Renormalization as Dimensional Analysis.)
O Fluxo de Ricci e Modelos σ Não-Lineares
[N.B.: A grande vantagem em se estudar Modelos σ não-lineares é que eles servem de "caso teste", de "modelo de brinquedo", para teorias de gauge, no sentido de que se considerarmos apenas seus temos cinéticos, já temos uma dinâmica extremamente rica; i.e., não é preciso, necessariamente, haver termos de pontecial pra haver uma dinâmica não trivial — no caso dos modelos σ não-lineares, essa dinâmica é dada pela métrica (não-trivial).]
Um modelo σ não-linear é uma QFT 2-dimensional onde 
onde 
![\exp\{-S[\phi;a^{-1}\, g]\}\, D_{g}[\phi]](http://s0.wp.com/latex.php?latex=%5Cexp%5C%7B-S%5B%5Cphi%3Ba%5E%7B-1%7D%5C%2C+g%5D%5C%7D%5C%2C+D_%7Bg%7D%5B%5Cphi%5D&bg=ffffff&fg=555555&s=0 "\exp\{-S[\phi;a^{-1}\, g]\}\, D_{g}[\phi]")
[N.B.: Há vários outros termos que poderiam ser adicionados à Ação acima ainda preservando a invariância por difeomorfismos (porém, tipicamente quebrando a invariância conforme). Os mais comuns são: táquion, dilaton e topológico. Mas, nós não vamos considerá-los aqui, para o bem da clareza de exposição. ]
Devemos notar que tipicamente o espaço 
Nesse ponto, pra não matar ninguém de tedius-maximus-totalis, , vou dar um pulinho… e ir direto pra parte que interessa, pro filezinho: o fluxo do grupo de renormalização para um modelo σ não-linear. Nas referências abaixo vcs podem encontrar os detalhes mais sórdidos.
Então, essencialmente, o fluxo do grupo de renormalização para modelos σ não-lineares, em 1-loop e 2-loops, é, respectivamente, o seguinte:
- 1-loop:
;
- 2-loops:
;
onde 
No “limite puntual” (i.e., acoplamento fraco, 
Geometricamente, esta é a equação de evolução fracamente-parabólica obtida através da deformação duma métrica Riemanniana, 
Em particular, o modelo σ não-linear é renormalizável (i.e., existe como uma teoria no contínuo) se, e somete se, começando da métrica nua 
[N.B.: A pergunta que fica, agora, é a seguinte, O que representam essas tais 'singularidades do fluxo de Ricci'? A resposta pra essa pergunta nos leva ao próximo (e último) assunto a ser tratado nesse post… mas, deixo uma diquinha: "transição de fases" e "quebra espontânea de simetria". ]
A Geometria do Fluxo de Ricci e Comentários sobre suas Singularidades
O fluxo de Ricci foi o ponto-de-partida e o exemplo motivador em importantes desenvolvimentos em Análise Geométrica, tendo seu ápice na prova da Conjectura da Geometrização de Thurston e da Conjectura de Poincaré! 
Então, isso torna ainda mais impressionante o fato de que fluxos de Ricci aparecem tão naturalmente na análise do grupo de renormalização de modelos σ não-lineares.
O fato geométrico que trabalha nos batidores para tornar toda essa mágica possível é que a função $beta; do fluxo do grupo de renormalização poder ser interpretada como sendo um campo vetorial no espaço de parâmetros, 
) Mais ainda, a função β é dada pela equação que define o fluxo de Ricci,
(A prova disso fica para o leitor interessado… mas também pode ser encontrada nas referências abaixo. )
O entendimento de como as soluções do fluxo de Ricci se comportam quando elas se aproximam um regime singular (i.e., quando elas vão chegando perto duma singularidade) é um passo chave para o uso do fluxo de Ricci (e.g., na prova da conjectura da geometrização). Mais ainda, de acordo com o que vimos na análise do fluxo do grupo de renormalização para modelos σ não-lineares, fica claro que nesse cenário também a formação de singularidades tem um papel fundamental — nesse caso, as soluções relevantes do fluxo de Ricci são as chamadas “ancient solutions”, aquelas que existem durante um intervalo máximo [de tempo], e correspondem a teorias renormalizáveis.
Uma classificação natural das singularidades pode ser feita com base na duração da existência de sua solução para o fluxo de Ricci e como essa solução escala assintoticamente. É possível também se usar técnicas de Convergência de Gromov-Hausdorff, em particular “point picking“.
Fica claro que o estudo da formação de singularidades é um dos tópicos principais na teoria de fluxos de Ricci, dado que ele provê o entendimento da estrutura das soluções em regimes de alta curvatura — em particular, a análise do “limite de colapso” do fluxo de Ricci é extremamente interessante: o colapso toma a forma duma simetria (“collapsing symmetry”) sob a qual o limite do fluxo de Ricci é eqüivariante (ver também Sistemas Dinâmicos Eqüivariantes, Eqüivariância e Cohomologia Eqüivariante). Esse é o fenômeno análogo à geração duma QFT a partir da quebra espontânea duma simetria. (Sem entrar em detalhes, sob a ação dessa “simetria de colapso”, as soluções limite do fluxo de Ricci passam a ter a estrutura dum Grupóide Riemanniano. Essa é uma noção familiar na teoria de foliações e no estudo de álgebras C* duma foliação — o que torna tudo ainda mais claro quando lembramos que cada solução duma dada QFT vive em sua própria folha e tem sua própria [representação] da álgebra C* em questão.) Portanto, há grande potencial e relevância em se usar esse tipo de técnica para se estudar o regime UV do grupo de renormalização em QFT.
Referências…
- Geometric analysis;
- Riemannian Geometry and Geometric Analysis;
- Lectures on Quantum Field Theory;
- Quantum Field Theory program at IAS: Fall Term (notas do Pierre Deligne e do Krzysztof Gawedzki);
- Quantum Fluctuations and Geometry: From Graph Counting to Ricci Flow.
Enquete…
Júbilo…
Diversão garantida…
A semana nos arXivs…
Depois de uma ausência maior do que desejada… voltamos com força total!
- Editorial: Is PRL Too Large to Have an “Impact”?
- Condensation of the roots of real random polynomials on the real axis
- Lie systems and integrability conditions of differential equations and some of its applications
- Effective Potential for Complex Langevin Equations
- The core Hopf algebra
- From Symmetry to Supersymmetry
- Quantum anomalies and some recent developments
- Quantum Fluctuations and Geometry: From Graph Counting to Ricci Flow
- A Look at the Abandoned Contributions to Cosmology of Dirac, Sciama and Dicke
- Conditional probabilities with Dirac observables and the problem of time in quantum gravity
- Gauging the twisted Poincaré symmetry as a noncommutative theory of gravitation
- Moduli spaces of Dirac operators for finite spectral triples
- Hamiltonian general relativity and the Belinskii–Khalatnikov–Lifshitz conjecture
- Introduction to BRS symmetry
A semana nos arXivs…
- A mechanism for mass
- A Supersymmetry Primer
- Conformal Field Theory and Algebraic Structure of Gauge Theory
- The vector wave equation in de Sitter space-time
- Towards a non-abelian electric-magnetic symmetry: the skeleton group
- The homogeneity conjecture for supergravity backgrounds
- Semiclassical analysis of the Loop Quantum Gravity volume operator: I. Flux Coherent States
- Modular theory for the von Neumann algebras of Local Quantum Physics
- The role of self-similarity in singularities of PDE’s
- Personnal recollections about the birth of string theory
- Replacing Anthropy with entropy: Does it work?
- Making use of the International Lattice Data Grid
- Partons, QCD and strings
- Profile of Sergio Ferreira
- Science Citation Index
- College vs. Employment
- Most Popular Top 10′s of 2008
- Canadense revela conexão chinesa no escândalo de revista científica
- Bad science: It’s not what the papers say, it’s what they don’t
- Should Politicians Defer to Scientists?
- Explain Science Commons in 2 minutes? Yes we can: Tom, esse é pra vc!
- The Magic of the Metric System
- Mathematical Sculptures
- CAN SCIENCE HELP SOLVE THE ECONOMIC CRISIS?
- When 2 + 2 = major anxiety: Math performance in stress situations
- What’s Inside a Black Hole
- Genetic Programming: Evolution of Mona Lisa: excelente vídeo — mostra os fundamentos de ‘programação genética’ e o quão longe receitas simples podem ir; quem duvida da Evolução, tem que ver…
A semana nos arXivs…
- On the History of Geometrization of Space-time: From Minkowski to Finsler Geometry
- From global symmetries to local currents: the free U(1) case in 4 dimensions
- Sur les formules locales de l’indice
- Massless scalar free Field in 1+1 dimensions, II: Net Cohomology and Completeness of Superselection Sectors
- Monopoles in arbitrary dimension
- A Causal Set Black Hole
- Modelling civilization as ‘heat engine’ could improve climate predictions
- BTZ black hole entropy: a spin foam model description
- From Quarks to Strings
- The Uncanny Precision of the Spectral Action
- On the resolution of the big bang singularity in isotropic Loop Quantum Cosmology
- Quantum geometrodynamics: whence, whither?
- On the Flow of Time
- Loop Quantum Cosmology: An Overview
- A Note on Distributional Semi-Riemannian Geometry
- Path integral representation of spin foam models of 4D gravity
- On the existence of soliton and hairy black hole solutions of Einstein–Yang–Mills theory with a negative cosmological constant
- Causal boundaries and holography on wave type spacetimes
- A note on Self-Dual Yang-Mills Theory
- Local aspects of free open bosonic string field theory
- Mathematical undecidability and quantum randomness
- Gauge Invariance in Field Theory and Statistical Physics in Operator Formalism
- Topological features of massive bosons on two dimensional Einstein space-time. I: Spatial approach
- Exploring knotting mechanisms in protein folding
- Incipient criticality in ecological communities
- Laws of population growth
- Beyond the Hoax: Science, Philosophy and Culture
- Coleman tribute
- Notes on BRST V: Highest Weight Theory
- Notes on BRST VI: Casimir Operators
- This Week’s Finds in Mathematical Physics (Week 272)
- Free multimedia education material on particle physics, accelerators
- Teias de ciência, editorial da “Folha de SP”
- Sonhos de Natal na revista Piauí
- Fernando Haddad ressalta na ABC a importância da interlocução com a comunidade científica e acadêmica
- L’affaire El Naschie, The Case of M. S. El Naschie, Continued
- The Numerati
- A Brief History of Software Engineering by Niklaus Wirth (PDF)
- The Feynman Lectures on Physics
- Science as a Way of Knowing
- Should you care about particle physics or the Higgs boson?
- Live Webcasts of 2008 Nobel Prize Award Ceremonies and Nobel Lectures
- Political and Technical Implications of GitTorrent
- The Incredible Convenience of Mathematica Image Processing
- Solving the Knight’s Tour Puzzle In 60 Lines of Python
A semana nos arXivs…
- A Note on Quantum Geometric Langlands Duality, Gauge Theory, and Quantization of the Moduli Space of Flat Connections
- On the symmetry of the vacuum in theories with spontaneous symmetry breaking
- Partition Functions of Matrix Models as the First Special Functions of String Theory. II. Kontsevich Model
- Lie Groups and mechanics: an introduction
- Classical and Quantum Mechanics via Lie algebras
- Empirical Tests of Zipf’s Law Mechanism in Open Source Linux Distribution
- Stability structures, motivic Donaldson-Thomas invariants and cluster transformations
- Gauged Laplacians on quantum Hopf bundles
- From Vector Analysis to Differential Forms
- Spectral Renormalization Group
- Renormalization flows in complex networks
- Algebro-geometric Feynman rules
- Quantum Criticality and Yang-Mills Gauge Theory
- Spontaneous symmetry breaking in loop quantum gravity
- Notes on BRST I: Representation Theory and Quantum Mechanics
- Notes on BRST II: Lie Algebra Cohomology, Physicist’s Version
- Notes on BRST III: Lie Algebra Cohomology
- Notes on BRST IV: Lie Algebra Cohomology for Semi-simple Lie Algebras
A semana nos arXivs…
- Self-organized criticality via stochastic partial differential equations
- GPU computing for 2-d spin systems: CUDA vs OpenGL
- Mathieu functions computational toolbox implemented in Matlab
- Quantum Gravity, CPT symmetry and Entangled States
- The Lyapunov Characteristic Exponents and their computation
- Recent algorithm and machine developments for lattice QCD
- Universality of citation distributions: Toward an objective measure of scientific impact
- First results from simulations of supersymmetric lattices
- Alternative path to the boundary: The CFT as the Fourier transform in AdS space
- Factorization in Dual Models and Functional Integration in String Theory
- The non-commutative geometry of matrix models: the Spinfoam way
- Some constructions in Category theory and Noncommutative geometry
- Quantum mechanical potentials related to the prime numbers and Riemann zeros
- Characterization of Lee-Yang polynomials
- Computer algebra in Java: libraries and scripting
- What is a particle?
- Variations on Pontryagin Duality
- Locally Compact Hausdorff Abelian Groups
- Undoing a quantum measurement
- How science is like democracy, Lee Smolin on TED
- The Case of M. S. El Naschie
Diversão garantida…
[]‘s.
As últimas três semanas nos arXivs…
Por causa da Third New England String Meeting, acabei saindo um pouco da minha rotina semanal de postar sobre os arXivs. Mas, voltando ao tema…
- Older scientists publish more papers e Late Bloomers: Why do we equate genius with precocity?
- Michael Atiyah on the foundations of philosophy, math and physics
- Exclusive interview with Yoichiro Nambu
- Physicist parent, musician child, and a documentary about the Everetts
- A outra crise: a da educacao
- Physics: A calling or assembly line
- Science not yet without borders
- The physics of networks
- Paris Hilton is Worried About Relativity
E, agora, para os arXivs…
- On second quantization on noncommutative spaces with twisted symmetries
- The Hilbert Transform of a Measure
- Lectures on black holes and linear waves
- Classical field theory. Advanced mathematical formulation
- Invariant geometry of the ideal gas
- A Simple Introduction to Particle Physics
- The fluid/gravity correspondence: Lectures notes from the 2008 Summer School on Particles, Fields, and Strings
- Confinement in Yang–Mills: Elements of a Big Picture
- Recent Progress in Formal Theory
- On the Structure of QFT in the Particle Picture of the Path Integral Formulation
- Quantum Curves and D-Modules
- Quantum group connections
- Model Categories and Quantum Gravity
- Black Holes, AdS, and CFTs
- Energy-momentum diffusion from spacetime discreteness
- Cosmology
- Lattice QCD: a critical status report
- Blasting through lattice calculations using CUDA
- Economics need a scientific revolution
- Ricci flows, wormholes and critical phenomena
- Announcement: Special issue on “Integrable Quantum Systems and Solvable Statistical Mechanics Models”
- Conifolds and geometric transitions
- θ parameter in loop quantum gravity: Effects on quantum geometry and black hole entropy
- Topological quantum numbers and curvature — examples and applications
Diversão garantida…
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