Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Renormalization group


Related Topics

  
  Renormalization group - Wikipedia, the free encyclopedia
Thus, the renormalization group is, in practice, a semigroup.
D.V. Shirkov (1999): Evolution of the Bogoliubov Renormalization Group.
A pedestrian introduction to renormalization and the renormalization group.
en.wikipedia.org /wiki/Renormalization_group   (1914 words)

  
 Renormalization - Wikipedia, the free encyclopedia
Renormalization arose in quantum electrodynamics as a means of making sense of the infinite results of various calculations and extracting finite answers to properly posed physical questions.
Initially viewed as a suspect, provisional procedure by most of its originators, renormalization eventually was embraced as an important tool in several fields of physics, as a result of work in effective field theory and the renormalization group.
According to the renormalization group insights, this splitting is unnatural and unphysical.
en.wikipedia.org /wiki/Renormalization   (3631 words)

  
 Renormalization group: Facts and details from Encyclopedia Topic   (Site not responding. Last check: 2007-11-07)
In quantum field theory (qft) and the statistical mechanics of fields, renormalization refers to a collection of techniques used to express physical calculations...
In mathematics, a group is a set, together with a binary operation, such as multiplication or addition, satisfying certain axioms, detailed below....
The density matrix renormalization group (dmrg) is a numerical technique originally intended to obtain the ground state of a quantum manybody system with high accura...
www.absoluteastronomy.com /encyclopedia/r/re/renormalization_group.htm   (1951 words)

  
 CERN Courier - Fifty years of the renormali - IOP Publishing - article
Renormalization was the breakthrough that made quantum field theory respectable in the late 1940s.
The most important feature of renormalization is that the calculation of physical quantities gives finite functions of new "renormalized" couplings (such as electron charge) and masses, all infinities being swallowed by the Z factors of the renormalization redefinition.
However, from the mid-1950s the Renormalization Group Method to improve approximate solutions to QFT equations became a powerful tool for investigating singular behaviour in both the ultraviolet (higher energy) and infrared (lower energy) limits.
www.cerncourier.com /main/article/41/7/14   (1737 words)

  
 [No title]   (Site not responding. Last check: 2007-11-07)
We discuss the renormalization flow on the basis of the continued fraction expansion of the frequency.
This accumulation motivates the setup of a renormalization transformation combining a {\em rescaling} of phase space and an {\em elimination} of the irrelevant part at each scale.\\ An attractive ({\em trivial}) fixed point of the renormalization represents the phase where the torus exists.
The renormalization $\mathcal{R}_{a_{s-1}} \mathcal{R}_{a_{s-2}}\cdots\mathcal{R}_{a_0}$ changes $\o=[a_0,a_1,\ldots]$ into $[a_s,a_{s+1},\ldots]$, and $\alpha$ into $[a_{s-1},a_{s-2},\ldots,a_0, b_0,b_1,\ldots]$.\\ If $\o$ has a periodic continued fraction expansion of period $s$, i.e., $\o=[(a_1,\ldots,a_s)_\infty]$, one expect to have a nontrivial fixed point on the critical surface of the renormalization transformation in which one step is defined by the composition $\mathcal{R}_{a_s} \mathcal{R}_{a_{s-1}}\cdots\mathcal{R}_{a_1}$.
www.ma.utexas.edu /mp_arc/papers/98-626   (2259 words)

  
 Supersymmetry - Wikipedia, the free encyclopedia
Supersymmetry was orginally developed in the 1970s by the research group of Jonathan I. Segal at MIT; at the same time Daniel Laufferty at Tufts University proposed a similar idea.
Put more simply, it means most quantum field theories predict that the mass of a scalar boson, when run down the renormalization group, is of the order of the cutoff scale (the scale at which new physics appears).
Traditional symmetries in physics are generated by objects that transform under the various tensor representations of the Poincaré group.
en.wikipedia.org /wiki/Supersymmetry   (1814 words)

  
 The Renormalization Group
In the renormalization method, we use the computer to change the configurations in a way that is similar to moving away from the photograph.
The second step is to determine the probability that characterizes the new configuration.  Each cell is assumed to be independent of all the other cells and characterized only by the probability that the cell is occupied i.e.
After one renormalization some of the original connecting paths are lost and some connecting paths not present in the original configuration are created.
www.physics.udel.edu /wwwusers/jim/percolation/renormalization.htm   (752 words)

  
 node1.html   (Site not responding. Last check: 2007-11-07)
Renormalization group (RG) theory is a powerful yet unusual modern method developed in the studies of phase transition and critical phenomena.
Let's draw an analogy between the fields of war and statistical physics: if the classical algebraic methods, such as mean field theory and cluster expansion approximation, are conventional weapons like guns and artillery, then the RG theory is nuclear bomb, which has helped physicists overcome huge difficulties.
For the renormalization function p'(p, b): p'(p=0.59, b=3)=0.78, and p'(p=0.78, b=3)=0.97.
www.people.fas.harvard.edu /~wu2/paper3/node1.html   (885 words)

  
 Renormalization Group Theory
The goal of this section is to introduce several concepts of Renormalization Group Theory and to illustrate such concepts with the 1-dimensional Ising model.
The renormalization group strategy for the 1-dimensional Ising model can be described as follows.
The renormalization group theory can then be implemented to compute the partition function of the system for a different value
xbeams.chem.yale.edu /~batista/vaa/node41.html   (383 words)

  
 Renormalization...
Renormalization is a legitimate technique for modifying the theory temporarily so that the parameters stay finite ("regularization"), and then at the end of the development removing the modifications in such a way that the infinities don't appear in the physics ("renormalization").
Theories for which an infinite number of parameters would have to be renormalized are called unrenormalizable, and they can't be developed with present methods as finite theories.
And just to add to what Patrick said, renormalization group methods are not instead of renormalization, they are in addition to it.
www.physicsforums.com /showthread.php?t=37431   (752 words)

  
 General formulation
The renormalization group (RG) has little to do with ``group theory'' as it is meant mathematically.
Also, there is no uniqueness to the renormalization group, so the use of ``the'' in this context is misleading.
Rather, the RG is an idea that exploits the physics of systems near their critical point which leads to a procedure for finding the critical point.
www.nyu.edu /classes/tuckerman/stat.mech/lectures/lecture_27/node4.html   (613 words)

  
 Mark Newman: Publications
Renormalization group analysis of the small-world network model, M.
A model for the shapes of islands and pits on (111) surfaces of fcc metals, G. Barkema, M. Newman, and M. Breeman, Phys.
Real-space renormalization group for the random-field Ising model, M.
www-personal.umich.edu /~mejn/pubs.html   (1578 words)

  
 Dynamical Renormalization Group Approach to Quantum Kinetics in Scalar and Gauge Theories   (Site not responding. Last check: 2007-11-07)
The solution of this equation of motion reveals secular terms that grow in time, the dynamical renormalization group resums these secular terms in real time and leads directly to the quantum kinetic equation.
A close relationship between this approach and the renormalization group in Euclidean field theory is established.
We obtain the relaxational and crossover time scales as a function of momentum and argue that infrared divergent damping rates are indicative of non-exponential relaxation, the dynamical renormalization group reveals the correct relaxation directly in real time.
int.phys.washington.edu /SEMINARS/Boyanovsky/talk.html   (443 words)

  
 Theory of Renormalization
When we renormalize physical quantities such as charge and mass, you might be thinking that these quantities are observable and are not infinte.
The renormalization group is a very complicated object, but I will just say a few things about it.
In addition, the renormalization group has helped to solve a number of questions in statistical mechanics, such as the behavior of magnets, liquid crystals and general phase transitions, just to name a few[6].
www.pha.jhu.edu /~blechman/papers/renormalization/node6.html   (542 words)

  
 ipedia.com: Phase transition Article   (Site not responding. Last check: 2007-11-07)
This non-analyticity generally stems from the interactions of an extremely large number of particles in a system, and does not appear in systems that are too small.
The first attempt at classifying phase transitions was the Ehrenfest classification scheme, which grouped phase transitions based on the degree of non-analyticity involved.
Universality is a prediction of the renormalization group theory of phase transitions, which states that the thermodynamic properties of a system near a phase transition depend only on a small number of features, such as dimensionality and symmetry, and is insensitive to the underlying microscopic properties of the system.
www.ipedia.com /phase_transition.html   (1948 words)

  
 RENORMALIZATION GROUP 2002   (Site not responding. Last check: 2007-11-07)
The 5-th International Conference Renormalization group 2002 (RG-2002) organized by the Joint Institute for Nuclear Research and the Institute of Experimental Physics Slovak Academy of Sciences, will be held at Hotel Academia in Stará Lesná, Slovak Republic from March 10 to 16, 2002.
The venue of the 5-th International Conference Renormalization group 2002 (RG-2002) has been moved to the Hotel Meander*** in Tatranska Strba located approximately 15 km to the west from Stará Lesná, also in the region of High Tatras.
This year it is already the 50-th anniversary of the publication of the article The normalization group in quantum theory by E.C.G. Stueckelberg and A. Petermann in Helvetica Physica Acta, where the term "normalization group" has been used, as far as we know, for the very first time.
www.saske.sk /UEF/OTF/RG   (212 words)

  
 Activity on Wilson Renormalization Group
This is a more elegant formulation of the Wilson's renormalization group equation (others well known forms of the evolution equation where given by Wegner and Houghton and by Polchinski) first introduced (independently) by Wetterich [
In particular, in perturbation theory it is possible to solve the so-called fine-tuning equations which say how to fix the ultraviolet non-invariant action in terms of renormalized parameters in such a way than the physical action becomes consistent with the gauge-symmetry (i.e.
To elucidate this problem we studied in detail the case of abelian gauge theories in the (unpublished) paper [BS] Wilson renormalization group and improved perturbation theory, M. Bonini, M. Simionato, UPRF-97-05, hep-th/9705146, 24pp.
www.phyast.pitt.edu /~micheles/curriculum/node7.html   (855 words)

  
 Density-matrix renormalization group
The Density Matrix Renormalization Group (DMRG) is one of the most powerful numerical techniques for studying many-body systems.
It was developed by Steve White in 1992 to overcome the problems arising in the application of the standard Numerical Renormalization Group (NRG) to quantum lattice many-body systems such as the Hubbard model of strongly correlated electrons.
In DMRG the states kept to construct a renormalization group transformation are the most probable eigenstates of a reduced density matrix instead of the lowest energy states kept in a standard NRG calculation.
komet337.physik.uni-mainz.de /Jeckelmann/DMRG   (636 words)

  
 Amazon.com: Lectures on Phase Transitions and the Renormalization Group (Frontiers in Physics, 85): Books: Nigel ...   (Site not responding. Last check: 2007-11-07)
Covering the elementary aspects of the physics of phases transitions and the renormalization group, this popular book is widely used both for core graduate statistical mechanics courses as well as for more specialized courses.
As other reader has put, this is not a classic book, in that the main focus is renormalization group, which is certainly a very dynamic field.
"Lectures on Phase Transitions and the Renormalization Group" is a good text, and a wonderful place to learn about the remormalization group in terms of real physical systems many of which can be measured in your basement (as opposed to HEP which, unless your basement happens to include fermilab is out-of-reach).
www.amazon.com /exec/obidos/tg/detail/-/0201554097?v=glance   (902 words)

  
 renormalization
It's fun to imagine turning a dial to adjust the distance scale D' and watching the physical coupling constants C' move around like a little dot in n-dimensional space, where n is the number of coupling constants.
If we assume the gravitational constant is reasonably large near the Planck scale, and we follow the renormalization group flow, we find that it's very small at macroscopic distance scales.
Whenever this sort of thing happens, we say the limiting value of C' is an "ultraviolet fixed point of the renormalization group".
math.ucr.edu /home/baez/renormalization.html   (4102 words)

  
 Renormalization group method
A second approach to the equilibrium behavior of random manifolds is the renormalization group treatment[4].
the coefficient of the stiffness term) only be renormalized by the scale changes (see, e.g.
Thus, in the long wavelength limit, the renormalized Hamiltonian is well-described simply by a renormalized potential.
online.itp.ucsb.edu /online/lnotes/balents/node16.html   (873 words)

  
 Renormalization Group   (Site not responding. Last check: 2007-11-07)
The geometric scaling and universality can both be understood from the "renormalization group theory" developed by Feigenbaum.
A more complete discussion needs more mathematical symbols than can be used with standard HTML: you can view it only if you download the IBM TechExplorer (sorry, Windows 95 or NT only!).
It is a remarkable result that these abstract mathematical constructions lead to numbers that can be measured in actual experiments on chaotic fluid and other systems.
www.cmp.caltech.edu /~mcc/chaos_new/Map_docs/rg.html   (296 words)

  
 Kenneth Wilson Curriculum Vitae - Publications
The Renormalization Group and Critical Phenomena I: Renormalization Group and the Kadanoff Scaling Picture.
The Renormalization Group and Critical Phenomena II: Phase Space Cell Analysis of Critical Behavior.
Renormalization of a Scalar Field in Strong Coupling.
www.physics.ohio-state.edu /~kgw/kgwpubs.html   (470 words)

  
 ELibM Book Review: Fermionic functional integrals and the renormalization group
These constructions are in general rather complicated because almost all models involve bosonic fields which require a combination of cluster expansions and large-field bounds in addition to renormalization.
The methods of constructive field theory, in particular the mathematical renormalization group (RG) method are well suited to treating this problem.
The renormalization group transformation is introduced to deal with singular covariances which are characteristic of physically interesting problems.
www.emis.de /misc/articles/FKT   (2102 words)

  
 Find in a Library: Renormalization : an introduction to renormalization, the renormalization group, and the ...
Find in a Library: Renormalization : an introduction to renormalization, the renormalization group, and the operator-product expansion
Renormalization : an introduction to renormalization, the renormalization group, and the operator-product expansion
WorldCat is provided by OCLC Online Computer Library Center, Inc. on behalf of its member libraries.
www.worldcatlibraries.org /wcpa/ow/baeed1c775bfd81ca19afeb4da09e526.html   (76 words)

  
 FIELD THEORY, THE RENORMALIZATION GROUP, AND CRITICAL PHENOMENA
Rigor and lengthy proofs are trimmed by using the phenomenological framework of graphs, power counting, etc., and field theoretic methods with emphasis on renormalization group techniques.
The Renormalization Group and Scaling the Critical Region
The second edition with a detailed exposition on finite size scaling, universality and the critical behavior with several coupling constants promises to be a valuable tool in the library of many physicists.”
www.worldscibooks.com /physics/5715.html   (296 words)

  
 LPTL: MMI   (Site not responding. Last check: 2007-11-07)
Renormalization group analysis of some dynamical systems with noise
* Workshop on renormalization in mathematics and physics, Paris, IHP, 14-16 Juin 1996.
II - Introduction to renormalization in dynamical systems.
www.lptmc.jussieu.fr /users/lesne   (1132 words)

  
 Makroskopische Systeme - Publikationen   (Site not responding. Last check: 2007-11-07)
in: J.-P. Gazeau et al (eds.), GROUP 24, Physical and Mathematical Aspects of Symmetries, Proceedings of the 24th International Colloquium on Group Theoretical Methods in Physics (Paris, July 15-20, 2002), Institute of Physics Conference Series No. 173 (2003), Institute of Physics Publishing, Bristol and Philadelphia, p.
M. Exler, J. Schnack, Evaluation of the low-lying energy spectrum of magnetic Keplerate molecules using the density-matrix renormalization group technique,
You may find more publications on the personal web sites of the group members.
www.physik.uos.de /makrosysteme/publ.htm   (1327 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.