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Horizon energy and angular momentum from a Hamiltonian perspective

Ivan Booth, Stephen Fairhurst
2005 Classical and quantum gravity  
In this paper we show that three-surfaces which can be foliated with such two-surfaces are suitable boundaries in both a quasilocal action and a phase space formulation of general relativity.  ...  The resulting formalism provides expressions for the quasilocal energy and angular momentum associated with the horizon.  ...  The methods that we will use are based on the generalized Hamiltonian formalisms of classical mechanics which are specifically designed to deal with situations like these where the energy isn't constant  ... 
doi:10.1088/0264-9381/22/21/006 fatcat:5nrz3c7dmzfb7n3fbgcjb5upee

Perspective: Quantum Hamiltonians for optical interactions

David L. Andrews, Garth A. Jones, A. Salam, R. Guy Woolley
2018 Journal of Chemical Physics  
The multipolar version of the Hamiltonian is commonly obtained by carrying out a unitary transformation of the Coulomb gauge Hamiltonian that goes by the name of Power-Zienau-Woolley (PZW).  ...  Recently, the foundations and validity of the PZW Hamiltonian have been questioned, raising a concern over issues of gauge transformation and invariance, and whether observable quantities obtained from  ...  The application of the general Hamiltonian method summarized in Sec.  ... 
doi:10.1063/1.5018399 pmid:29390804 fatcat:dleeew4rhvepriq2p7fvfwvycy

An Examination of the Time-Centered Difference Scheme for Dissipative Mechanical Systems from a Hamiltonian Perspective [article]

Tianshu Luo, Yimu Guo
2010 arXiv   pre-print
On this paper, we have proposed an approach to observe the time-centered difference scheme for dissipative mechanical systems from a Hamiltonian perspective and to introduce the idea of symplectic algorithm  ...  The dissipative mechanical systems discussed in this paper are finite dimensional.This approach is based upon a proposition: for any nonconservative classical mechanical system and any initial condition  ...  approach is a so-called generating function method.  ... 
arXiv:1007.2709v1 fatcat:k6zc5el2azhhdmdsrludwqb7qy

Hamiltonian methods: BRST, BFV

J. Antonio García
2006 AIP Conference Proceedings  
The range of applicability of Hamiltonian methods to gauge theories is very diverse and cover areas of research from phenomenology to mathematical physics.  ...  They cover the study of symplectic methods, BRST-BFV and BV approaches, Klauder projector program, and non perturbative technics used in the study of bound states in relativistic field theories.  ...  ACKNOWLEDGMENTS It is a pleasure to thanks V. M. Villanueva, R. Cartas-Fuentevilla and A. Weber for their contribution to sections 2, 3, and 4 respectively.  ... 
doi:10.1063/1.2359407 fatcat:w5un2ovn6ndpnhpbbquek5vi4a

New applications of Renormalization Group methods to nuclear matter

Kai Hebeler
2012 arXiv   pre-print
We give an overview of recent results for the nuclear equation of state and properties of neutron stars based on microscopic two- and three-nucleon interactions derived within chiral effective field theory  ...  Neutron matter provides a different perspective to nucleonic matter.  ...  FIGURE 2. left panel: (from Ref. [6]) Nuclear matter energy as a function of the Fermi momentum based on NN+3NF forces compared to NN-only results for two representative NN cutoffs and a fixed 3N cutoff  ... 
arXiv:1208.4297v1 fatcat:f6bsyzjsg5ebxe6u2pvxbiebie

Hamiltonian methods: BRST, BFV

J. Antonio García Zenteno
2011 Revista Vectores de Investigación  
A systematic Hamiltonian approach based on the BRST symmetry 3 developed by E. S. Fradkin and his collaborators 4 , 2 "Generalized Hamiltonian Dynamics" Can. J.  ...  Hamiltonian non perturbative Methods in Gauge Theories A given Hamiltonian His split into a "free" (solvable) part H 0 and an "interacting" part H 1 , H = H 0 + H 1 .Then a generalization of the Gell-Mann-Low  ... 
doaj:5aadd2a947fb4dffaeab48f8a13beeec fatcat:j2q6qz2265bb7gn6zqv5mnvfxi

The Vertical Logic of Hamiltonian Methods (Part 1) [article]

C. Baumgarten
2022 arXiv   pre-print
We discuss the key role that Hamiltonian notions play in physics. Five examples are given that illustrate the versatility and generality of Hamiltonian notions.  ...  We demonstrate that a derivation of these core concepts of modern physics requires little more than a proper formulation in terms of classical Hamiltonian theory.  ...  L A T E X has been used to write this article, XFig 3.2.5 for the figures. Mathematica ® has originally been used for parts of the symbolic calculations.  ... 
arXiv:2001.03412v6 fatcat:hmuvyja2aza7tiwzauerwquh5a

Numerical methods for Hamiltonian PDEs

Thomas J Bridges, Sebastian Reich
2006 Journal of Physics A: Mathematical and General  
The equations (13) are the shallow-water momentum equations from a Lagrangian fluid dynamics perspective.  ...  They show robust behaviour and excellent energy and momentum conservation, but a comparison with finite-difference based methods has not been carried out.  ...  Appendix We give a brief description of the numerical experiment from §1. The Preissman box scheme (25) has been applied to the multi-symplectic formulation (14) of the wave equation (1)  ... 
doi:10.1088/0305-4470/39/19/s02 fatcat:ndsorkrjvfhkdelbjrlqlq6l6q

Hamiltonian Monte Carlo Methods for Subset Simulation in Reliability Analysis [article]

Ziqi Wang, Marco Broccardo, Junho Song
2018 arXiv   pre-print
The HMC method relies on a deterministic mechanism inspired by Hamiltonian dynamics to propose samples following a target probability distribution.  ...  This paper studies a non-random-walk Markov Chain Monte Carlo method, namely the Hamiltonian Monte Carlo (HMC) method in the context of Subset Simulation used for structural reliability analysis.  ...  The Hamiltonian Monte Carlo method uses a deterministic procedure inspired by Hamiltonian mechanics to generate samples based on the target probability distribution.  ... 
arXiv:1706.01435v2 fatcat:6mkskaj52zhmrgadzdbozh67k4

Numerical methods for General Relativistic particles [article]

Fabio Bacchini, Bart Ripperda, Lorenzo Sironi
2018 arXiv   pre-print
Efficient numerical methods are required for solving the equations of motion and compute i) the black hole shadow obtained by tracing light rays from the object to a distant observer, and ii) obtain information  ...  Here, we present generalized algorithms capable of simulating ensembles of photons or massive particles in any spacetime, with the option of including external forces.  ...  Introduction and overview Particle-based numerical methods are a powerful tool in plasma physics.  ... 
arXiv:1810.01153v2 fatcat:mmc5ig4bdfdjzelkvcx5c2nxuu

Unitary correlation operator method and similarity renormalization group: Connections and differences

R. Roth, S. Reinhardt, H. Hergert
2008 Physical Review C  
After contrasting the two conceptual frameworks, we establish a formal connection between the initial SRG-generator and the static generators of the UCOM transformation.  ...  Method (UCOM).  ...  UCOM from an SRG perspective One can consider the UCOM generators (18) and (19) also from an SRG perspective.  ... 
doi:10.1103/physrevc.77.064003 fatcat:jo2c77iew5gxnahjy2dfkyvz4i

Operator Methods for the Time Evolution of Wave Functions [article]

K. P. Michnicki
2012 arXiv   pre-print
A method based off of operator consideration for solving the time evolution of a wave function is developed.  ...  A method to obtain exact solutions to Heisenberg's equations of motion is developed based off of solutions of classical equations of motion.  ...  In fact, problems can occur that have a simple solution if you switch to a basis that is a mixture of both momentum and position bases.  ... 
arXiv:0811.3431v2 fatcat:32dezaznbvahnk6pe24albqm6e

Improving Actor-Critic Reinforcement Learning via Hamiltonian Monte Carlo Method [article]

Duo Xu, Faramarz Fekri
2022 arXiv   pre-print
As such we propose to evolve actions from the base policy according to HMC, and our proposed method has many benefits.  ...  Further, instead of directly applying HMC into RL, we propose a new leapfrog operator to simulate the Hamiltonian dynamics.  ...  Hamiltonian Monte Carlo Hamiltonian Monte Carlo (HMC) is a popular MCMC method for generating sequence of samples, which converge to being distributed according to the target distribution [29] .  ... 
arXiv:2103.12020v3 fatcat:oys57frqe5ckxloywgxomhf55u

Developed Method. Interactions and their quantum picture [article]

Piotr Ogonowski
2023 arXiv   pre-print
For a system with an electromagnetic field, the Lagrangian density equal to the invariant of the electromagnetic field was obtained, vanishing four-divergence of canonical four-momentum appears to be consequence  ...  The proposed method allows for further development with additional fields.  ...  The author also tries to bring his own contribution to the explanation of the above physics challenges, based on a recently discovered method, described in [19] .  ... 
arXiv:2306.14906v4 fatcat:4d6lscgkijb3fdhdgv4vnlve6y

Exact Methods for Self Interacting Neutrinos [article]

Y. Pehlivan, A. B. Balantekin, Toshitaka Kajino
2013 arXiv   pre-print
In particular, we show that a neutrino spectral split can be simply viewed as an avoided level crossing between the eigenstates of a mean field Hamiltonian which includes a Lagrange multiplier in order  ...  as the well known BCS pairing Hamiltonian.  ...  The Hamiltonian in Eq. (8) has the same form in both the mass and flavor bases because these bases are related by a global rotation which leaves all scalar products invariant.  ... 
arXiv:1311.0143v1 fatcat:ivadpcidejdnjcbad3zsxbwwmm
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