Search results for " quantum mechanics"

Generalization of thermodynamics allowing negentropic entanglement and a model for conscious information processing

2011

Costa de Beauregard considers a model for information processing by a computer based on an analogy with Carnot's heat engine. I am grateful for Stephen Paul King for bringing this article to my attention in Time discussion group and also for inspiring discussions which also led to the birth of this section. As such the model Beauregard for computer does not look convincing as a model for what happens in biological information processing. Combined with TGD based vision about living matter, the model however inspires a model for how conscious information is generated and how the second law of thermodynamics must be modified in TGD framework. The basic formulas of thermodynamics remain as such…

Tēze: Dalījums fizikā, reliģijā un mistikā ir ... mistika/līdz aplamībai novecojusi lieta

No trim minētajām jomām fizika ir visvairāk sasniegusi realitātes aizsniegšanai, galvenokārt pateicoties kvantu mehānikas sasniegumiem, bet tās nodalīšanās no divām citām jomām kavē pašas tās attīstību. Vēl vairāk, fizika pati iekrīt savā misticismā un varbūt arī pašdarinātā reliģijā - ja tas vēl nav noticis, tad tas notiks - ja tā neizdarīs radikālus apvērsumus savās nostādnēs, kas to vairs nešķirs no augšminētajām jomām.

On to what effect LHC experiment should arrive

2010

We consider idea of hierarchical multitime notion and of the cone of creation. Following this idea, the time used in traditional sense is only a single projection of time in the multitime. Multitime must have inner dimension upwards turning it into hierarchical structure which acts as what we call global cone of creation. On our time projection, evolution of species and BB, both global and local, in SM are examples of local cones of creation. Higgs field as symmetry breaking accounts for complementary worlds on other projections of time in multitime. We argue that time is form of referencing within matter and doesn’t have any sense without matter. These are the hypothetical assumptions whic…

Fermion masses and unitarity without a Higgs boson

2004

We discuss the consistency of fermion mass generation by boundary conditions and brane localized terms in higher dimensional models of gauge symmetry breaking without a Higgs boson. The sum rules imposed by tree-level unitarity and Ward identities are applied to check the consistency of mass generation by orbifold projections and more general boundary conditions consistent with the variational principle. We find that the sum rules are satisfied for boundary conditions corresponding to brane localized mass and kinetic terms consistent with the reduced gauge symmetry on the brane.

Dipole excitations of neutron-proton asymmetric nuclei

2004

Dipole excitations of unstable short-lived nuclei has been investigated experimentally by utilizing the electromagnetic-excitation process with high-energy secondary beams. From an exclusive measurement of the neutron-decay channels, differential cross sections with respect to excitation energy, which are directly related to the photo-absorption cross section and accordingly to the dipole-strength function, have been derived. Light neutron-rich nuclei in the mass range fromA = 11 toA = 23 with mass-over-charge ratios up toA/Z≈ 2.8 have been investigated systematically. Much in contrast to stable nuclei, low-lying dipole excitations well below the giant dipole resonance region have been obse…

Charm quark mass with calibrated uncertainty

2016

We determine the charm quark mass ${\hat m}_c({\hat m}_c)$ from QCD sum rules of moments of the vector current correlator calculated in perturbative QCD. Only experimental data for the charm resonances below the continuum threshold are needed in our approach, while the continuum contribution is determined by requiring self-consistency between various sum rules, including the one for the zeroth moment. Existing data from the continuum region can then be used to bound the theoretical error. Our result is ${\hat m}_c({\hat m}_c) = 1272 \pm 8$ MeV for $\hat\alpha_s(M_Z) = 0.1182$. Special attention is given to the question how to quantify and justify the uncertainty.

Semileptonic decays of theBcmeson

2001

We study the semileptonic transitions ${B}_{c}\ensuremath{\rightarrow}{\ensuremath{\eta}}_{c},$ $J/\ensuremath{\psi},$ D, ${D}^{*},$ B, ${B}^{*},$ ${B}_{s},$ ${B}_{s}^{*}$ in the framework of a relativistic constituent quark model. We use experimental data on leptonic $J/\ensuremath{\psi}$ decay, lattice and QCD sum rule results on leptonic ${B}_{c}$ decay, and experimental data on radiative ${\ensuremath{\eta}}_{c}$ transitions to adjust the quark model parameters. We compute all form factors of the above semileptonic ${B}_{c}$ transitions and give predictions for various semileptonic ${B}_{c}$ decay modes including their $\ensuremath{\tau}$ modes when they are kinematically accessible. Th…

Par zinātni kā instrumentalitāti: �kas mainījies pēc kvantu mehānikas ienākšanas epistemoloģijā

2011

The pion polarisability from QCD sum rules

1994

Abstract The electromagnetic polarisability of charged pions, α E , has recently attracted both theoretical and experimental attention. Unfortunately the experimental results disagree with each other. We have investigated this polarisation via a QCD sum rule approach and find α E = 5.6 ± 0.5 × 10 −4 fm 3 , which is in agreement with one experiment and disagrees with the result of chiral perturbation theory.

Chiral dynamics in the low-temperature phase of QCD

2014

We investigate the low-temperature phase of QCD and the crossover region with two light flavors of quarks. The chiral expansion around the point $(T,m=0)$ in the temperature vs. quark-mass plane indicates that a sharp real-time excitation exists with the quantum numbers of the pion. An exact sum rule is derived for the thermal modification of the spectral function associated with the axial charge density; the (dominant) pion pole contribution obeys the sum rule. We determine the two parameters of the pion dispersion relation using lattice QCD simulations and test the applicability of the chiral expansion. The time-dependent correlators are also analyzed using the Maximum Entropy Method, yie…