4,538 research outputs found
FIELD THEORY, THE RENORMALIZATION GROUP, AND CRITICAL PHENOMENA Graphs to Computers (Third Edition)
No full textDynamic structure factor of the three-dimensional Ising model with purely relaxational dynamics
No full textWe compute the dynamic structure factor for the three-dimensional Ising model with a purely relaxational dynamics (model A). We perform a perturbative calculation in the epsilon expansion, at two loops in the high-temperature phase and at one loop in the temperature magnetic-field plane, and a Monte Carlo simulation in the high-temperature phase. We find that the dynamic structure factor is very well approximated by its mean-field Gaussian form up to moderately large values of frequency omega and momentum k. In the region we can investigate, kxiless than or similar to5, omegatauless than or similar to10, where xi is the correlation length and tau is the zero-momentum autocorrelation time, deviations are at most of a few percent
Three-dimensional randomly dilute Ising model: Monte Carlo results
No full textWe perform a high-statistics simulation of the three-dimensional randomly dilute Ising model on cubic lattices L(3) with Lless than or equal to256. We choose a particular value of the density, x=0.8, for which the leading scaling corrections are suppressed. We determine the critical exponents, obtaining nu=0.683(3), eta=0.035(2), beta=0.3535(17), and alpha=-0.049(9), in agreement with previous numerical simulations. We also estimate numerically the fixed-point values of the four-point zero-momentum couplings that are used in field-theoretical fixed-dimension studies. Although these results somewhat differ from those obtained using perturbative field theory, the field-theoretical estimates of the critical exponents do not change significantly if the Monte Carlo result for the fixed point is used. Finally, we determine the six-point zero-momentum couplings, relevant for the small-magnetization expansion of the equation of state, and the invariant amplitude ratio R(xi)(+) that expresses the universality of the free-energy density per correlation volume. We find R(xi)(+)=0.2885(15)
Phonons in supercooled liquids: a possible explanation for the Boson Peak
No full textpreprint cond-mat/030110
Martin v. Divers (1799) 2
No full textMayor\u27s court regarding Martin v. Divers. New York. Image 2 of 2.https://digitalcommons.lmu.edu/tiersma_collection/1940/thumbnail.jp
Martin v. Divers (1799) 2
No full textMayor\u27s court regarding Martin v. Divers. New York. Image 2 of 2.https://digitalcommons.lmu.edu/tiersma_collection/1940/thumbnail.jp
Martin v. Divers (1799) 1
No full textMayor\u27s court regarding Martin v. Divers. New York. Image 1 of 2.https://digitalcommons.lmu.edu/tiersma_collection/1939/thumbnail.jp
Martin v. Divers (1799) 1
No full textMayor\u27s court regarding Martin v. Divers. New York. Image 1 of 2.https://digitalcommons.lmu.edu/tiersma_collection/1939/thumbnail.jp
Cumulative overlap distribution function in realistic spin glasses
No full textWe use a sample-dependent analysis, based on medians and quantiles, to analyze the behavior of the overlap
probability distribution of the Sherrington-Kirkpatrick and 3D Edwards-Anderson models of Ising spin glasses.
We find that this approach is an effective tool to distinguish between replica symmetry breaking–like and
droplet-like behavior of the spin-glass phase. Our results are in agreement with a replica symmetry breaking–like
behavior for the 3D Edwards-Anderson model
The three-dimensional randomly dilute Ising model: Monte Carlo results
No full textWe perform a high-statistics simulation of the three-dimensional randomly
dilute Ising model on cubic lattices with . We choose a
particular value of the density, x=0.8, for which the leading scaling
corrections are suppressed. We determine the critical exponents, obtaining , , , and ,
in agreement with previous numerical simulations. We also estimate numerically
the fixed-point values of the four-point zero-momentum couplings that are used
in field-theoretical fixed-dimension studies. Although these results somewhat
differ from those obtained using perturbative field theory, the
field-theoretical estimates of the critical exponents do not change
significantly if the Monte Carlo result for the fixed point is used. Finally,
we determine the six-point zero-momentum couplings, relevant for the
small-magnetization expansion of the equation of state, and the invariant
amplitude ratio that expresses the universality of the free-energy
density per correlation volume. We find
- …
