Results 81 to 90 of about 165,231 (345)

A New Class of Group Field Theories for 1st Order Discrete Quantum Gravity

, 2007
Group Field Theories, a generalization of matrix models for 2d gravity, represent a 2nd quantization of both loop quantum gravity and simplicial quantum gravity.
Baez J C, Barrett J W, D Oriti, Engle J Pereira R Rovelli C, Freidel L, Freidel L, Freidel L Krasnov K, Freidel L Krasnov K Oriti D, Gelfand I M, Gradshteyn I S, Hamber H W, Hermann R, Livine E Speziale S, Oriti D, Oriti D, Oriti D, Oriti D, Perez A, Perez A Bojowald M, Reisenberger M, Rivers R J, Rovelli C, T Tlas, Williams R   +23 more
core   +1 more source

On the symmetries of BF models and their relation with gravity [PDF]

, 2001
The perturbative finiteness of various topological models (e.g. BF models) has its origin in an extra symmetry of the gauge-fixed action, the so-called vector supersymmetry.
A. Boresch, C.P. Constantinides, Clisthenis P Constantinidis, E. Witten, F. Gieres, F. Gieres, F. Langouche, François Gieres, G.T. Horowitz, H. Ikemori, H. Ikemori, H.-J. Matschull, I.A. Batalin, K. Ezawa, L. Baulieu, L. Freidel, L. Freidel, M. Blau, Marcelo S Sarandy, N. Maggiore, O. Piguet, O. Piguet, Olivier Piguet, P. Peldán, R. A. Bertlmann, R. Stora   +25 more
core   +3 more sources

Encoding Cumulation to Learn Perturbative Nonlinear Oscillatory Dynamics

Advanced Science, EarlyView.
Weak nonlinearities critically shape the long term behavior of oscillatory systems but are difficult to identify from data. A data‐driven framework is introduced to infer governing equations of weakly nonlinear oscillators from sparse and noisy observations.
Teng Ma, Ting‐Ting Gao, Wei Cui, Attilio Frangi, Gang Yan, Lin Zhao   +5 more
wiley   +1 more source

Matrix Models, Emergent Gravity, and Gauge Theory

, 2009
Matrix models of Yang-Mills type induce an effective gravity theory on 4-dimensional branes, which are considered as models for dynamical space-time. We review recent progress in the understanding of this emergent gravity.
Austing P, Grosse H, Harold Steinacker, Klammer D, Matusis A, Minwalla S, Sakharov A D, Sakharov A D, Seiberg N, Steinacker H, Steinacker H   +10 more
core   +1 more source

3D‐Printed Architected Anisotropic Channels for Ultrafast Solar‐Driven Interfacial Evaporation via Localized Thermal Management and Water Layer Structuring

Advanced Science, EarlyView.
A 3D‐printed anisotropic channel evaporator integrates directional geometry with aligned titanium oxide, boron nitride, and chitosan networks to coordinate photon absorption, heat localization, and water transport. Phonon‐guided thermal pathways and interfacial water structuring enable ultrahigh evaporation rates and long‐term salt‐resistant solar ...
Sijia Sun, Dong Jiang, Hengsong Zheng, Shuai Zhang, Ziyuan Cheng, Changtong Mei, Dan Tian, Shilong Yang, Yusuke Yamauchi, Mingzhu Pan   +9 more
wiley   +1 more source

The cosmological constant as a boundary term

Journal of High Energy Physics, 2022
We compare the path integral for transition functions in unimodular gravity and in general relativity. In unimodular gravity the cosmological constant is a property of states that are specified at the boundaries whereas in general relativity the ...
Wilfried Buchmüller, Norbert Dragon
doaj   +1 more source

Noncomputability arising in dynamical triangulation model of four-dimensional Quantum Gravity [PDF]

Communications in Mathematical Physics, 1993
Computations in Dynamical Triangulation Models of Four-Dimensional Quantum Gravity involve weighted averaging over sets of all distinct triangulations of compact four-dimensional manifolds. In order to be able to perform such computations one needs an algorithm which for any given $N$ and a given compact four-dimensional manifold $M$ constructs all ...
Nabutovsky, A., Ben-Av, R.
openaire   +3 more sources

Unitarity bounds on low scale quantum gravity

, 2010
We study the unitarity of models with low scale quantum gravity both in four dimensions and in models with a large extra-dimensional volume. We find that models with low scale quantum gravity have problems with unitarity below the scale at which gravity ...
A. Datta, A. Simone De, A. Vayonakis, B. Grzadkowski, B. Grzadkowski, B.S. DeWitt, C. Amsler, C.P. Burgess, C.T. Hill, D.N. Kabat, D.V. Vassilevich, F. Larsen, F.A. Berends, F.L. Bezrukov, H. Dam van, I. Antoniadis, I. Antoniadis, J. Chakrabortty, J. Hewett, J.L.F. Barbon, K. Huitu, K. Tobe, L. Randall, L.A. Anchordoqui, L.J. Hall, M. Kachelriess, M.T. Grisaru, Michael Atkins, N. Arkani-Hamed, Q. Shafi, S. Hannestad, S. Hannestad, S.R. Huggins, T. Dasgupta, T. Han, T.G. Rizzo, V.I. Zakharov, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X. Calmet, X.G. He, Xavier Calmet   +50 more
core   +2 more sources

Soft Robotics and Advanced Technologies for Minimally Invasive Bioprinting: The Future of Internal Organ Repair

Advanced Science, EarlyView.
This review examines the evolution of bioprinting toward minimally invasive in situ strategies for internal organ regeneration. It defines the technological roadmap from handheld systems to advanced minimally invasive bioprinting platforms, positioning soft robotics as a core enabler.
Duc Tu Vu, Nhu An Phan, Sy Trung Ngo, Minh Tri Phan, Thanh‐An Truong, Chi Cong Nguyen, Phuoc Thien Phan, Hoang‐Phuong Phan, Thanh Nho Do, Mai Thanh Thai   +9 more
wiley   +1 more source

Null infinity as an open Hamiltonian system

Journal of High Energy Physics, 2021
When a system emits gravitational radiation, the Bondi mass decreases. If the Bondi energy is Hamiltonian, it can thus only be a time-dependent Hamiltonian. In this paper, we show that the Bondi energy can be understood as a time-dependent Hamiltonian on
Wolfgang Wieland
doaj   +1 more source