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This is a segment of episode 328 of Last Born In The Wilderness \"Infrastructural Brutalism: The Great Acceleration & Brisantic Politics w/ Michael Truscello.\" Listen to the full episode: https://www.lastborninthewilderness.com/episodes/michael-truscelloLearn more about Michael's work: https://www.michaeltruscello.comMichael Truscello joins me to discuss his book 'Infrastructural Brutalism: Art and the Necropolitics of Infrastructure,' in which he \"looks at the industrial infrastructure not as an invisible system of connectivity and mobility that keeps capitalism humming in the background but as a manufactured miasma of despair, toxicity, and death. Truscello terms this \"infrastructural brutalism\"-a formulation that not only alludes to the historical nexus of infrastructure and the concrete aesthetic of Brutalist architecture but also describes the ecological, political, and psychological brutality of industrial infrastructures.\"What is infrastructure? How does it shape our lives, direct our movements, and inform our worldviews? And, furthermore, what is the nature of the systems that produce the kinds of infrastructure we live our lives within and through? As Michael Truscello identifies in his book 'Infrastructural Brutalism,' there is a brutal logic that underlies the infrastructure projects of the 20th and 21st centuries. Especially in a time of mass extinction and accelerated climate catastrophe, the very fact that the largest infrastructure project in human history, the Belt and Road Initiative, is currently underway in China speaks to the suicidal urge inherent within the imperatives of the global capitalist order. In spite of the present and accelerating collapse of the biosphere, nation states and their corporate beneficiaries are racing to pave more roads, lay down more rail lines and pipelines, construct more power plants, airports, and seaports, and consequentially, decimate more ecosystems in the pursuit of technological and geopolitical dominance. Truscello walks us through this predicament, as well as what a multiplicitous response to these crises may contain. And finally, he discusses his fascinating study of various art forms that grapple with the hollow promises and lived brutalities of industrial infrastructure.Michael Truscello, Ph.D., is an associate professor in English and General Education at Mount Royal University in Calgary, Alberta. He is the author of 'Infrastructural Brutalism: Art and the Necropolitics of Infrastructure' (MIT Press, 2020) and co-editor with Ajamu Nangwaya of 'Why Don't The Poor Rise Up? Organizing the Twenty-First Century Resistance' (AK Press, 2017). His recent publications on petrocultures have appeared as chapters in 'Petrocultures: Oil, Culture, Politics '(McGill-Queen's UP, 2017), 'Interrogating the Anthropocene: Ecology, Aesthetics, Pedagogy, and the Future in Question' (Palgrave Macmillan, 2018) and 'Fueling Culture' (Fordham UP, 2017). He directed the film 'Capitalism Is The Crisis: Radical Politics in the Age of Austerity' (2011). He acknowledges that he lives and works on Treaty 7 territory, the ancestral and traditional territory of the Blackfoot Confederacy: Kainai, Piikani and Siksika as well as the Tsuu T'ina First Nation and Stoney Nakoda First Nation.WEBSITE: https://www.lastborninthewilderness.comPATREON: https://www.patreon.com/lastborninthewildernessDONATE: https://www.paypal.me/lastbornpodcast / https://venmo.com/LastBornPodcastBOOK LIST: https://bookshop.org/shop/lastbornpodcastEPISODE 300: https://lastborninthewilderness.bandcamp.comBOOK: http://bit.ly/ORBITgrATTACK & DETHRONE: https://anchor.fm/adgodcastDROP ME A LINE: Call (208) 918-2837 or http://bit.ly/LBWfiledropEVERYTHING ELSE: https://linktr.ee/patterns.of.behavior

Brendocha live for Acceleration Radio, 2024-05-04

Results are presented of a numerical integration of the three-dimensional relativistic equations of motion of electrons subject to given electric and magnetic fields deduced from experiments. Fields due to two different models are investigated. For the first model, the fields are those due to a circular distribution of axial current filaments. As the current filaments collapse toward the axis, large azimuthal magnetic and axial electric fields are induced. These fields effectively heat the electrons to a temperature of approximately 8 keV and accelerate electrons within the radius of the filaments to high axial velocities. Similar results are obtained for the current-reduction phase of focus formation. For the second model, the fields are those due to a uniform current distribution. Both the current-reduction and the compression phases were studied. These is little heating or acceleration of electrons during the compression phase because the electrons are tied to the magnetic field. However, during the current-reduction phase, electrons near the axis are accelerated toward the center electrode and reach energies of 100 keV. A criterion is obtained which limits the runaway electron current to about 400 A.

We analyze the transformation of quantum fields under conformal coordinate transformations from inertial to accelerated frames, in the simple case of scalar massless fields in a two-dimensional spacetime, through the transformation of particle number and its spectral density. Particle number is found to be invariant under conformal coordinate transformations to uniformly accelerated frames, which extends the property already known for vacuum. Transformation of spectral density of particle number exhibits a redistribution of particles in the frequency spectrum. This redistribution is determined by derivatives of phase operators with respect to frequency, that is by time and position operators defined in such a manner that the redistribution of particles appears as a Doppler shift which depends on position in spacetime, in conformity with Einstein equivalence principle.

More #questions that #science Does not have a definite answer for. I think I have the answer for the bicycle and gravity. Acceleration.#easy-MO5U2T2rIUv.mp4 More questions that science Does not have a definite answer for I think I have the answer for the bicycle and gravity Acceleration easy MO5U2T2rIUv mp4 questions science easy

Shocks in astrophysical fluids can generate suprathermal particles by first order (or diffusive) Fermi acceleration. In the test particle regime there is a simple relation between the spectrum of the accelerated particles and the jump conditions at the shock. This simple picture becomes complicated when the pressure of the accelerated particles becomes comparable with the pressure of the shocked fluid, so that the non-linear backreaction of the particles becomes non negligible and the spectrum is affected in a substantial way. Though only numerical simulations can provide a fully self-consistent approach, a more direct and easily applicable method would be very useful, and would allow to take into account the non-linear effects in particle acceleration in those cases in which they are important and still neglected. We present here a simple semi-analytical model that deals with these non-linear effects in a quantitative way. This new method, while compatible with the previous simplified results, also provides a satisfactory description of the results of numerical simulations of shock acceleration.

Benelli 900 SEI Exhaust Sound And Acceleration Compilation

Operation Acceleration (Rev 17-10; 18-1-24 Sunday 11-13-11 PM Pastor Jon White)

Thesis (MS)--U.S. Naval Postgraduate School, 1961

From considerations of safety and reliability in performance of gas-turbine aircraft, it is clear that engine starting and acceleration are of utmost importance. For this reason extensive efforts have been devoted to the investigation of the factors involved in the starting and acceleration of engines. In chapter III it is shown that certain basic combustion requirements must be met before ignition can occur; consequently, the design and operation of an engine must be tailored to provide these basic requirements in the combustion zone of the engine, particularly in the vicinity of the ignition source. It is pointed out in chapter III that ignition by electrical discharges is aided by high pressure, high temperature, low gas velocity and turbulence, gaseous fuel-air mixture, proper mixture strength, and-an optimum spark. duration. The simultaneous achievement of all these requirements in an actual turbojet-engine combustor is obviously impossible, yet any attempt to satisfy as many requirements as possible will result in lower ignition energies, lower-weight ignition systems, and greater reliability. These factors together with size and cost considerations determine the acceptability of the final ignition system. It is further shown in chapter III that the problem of wall quenching affects engine starting. For example, the dimensions of the volume to be burned must be larger than the quenching distance at the lowest pressure and the most adverse fuel-air ratio encountered. This fact affects the design of cross-fire tubes between adjacent combustion chambers in a tubular-combustor turbojet engine. Only two chambers in these engines contain spark plugs; therefore, the flame must propagate through small connecting tubes between the chambers. The quenching studies indicate that if the cross-fire tubes are too narrow the flame will not propagate from one chamber to another. In order to better understand the role of the basic factors in actual engine operation, many investigations have been conducted in single combustors from gas-turbine engines and in full-scale engines in altitude tanks and in flight. The purpose of the present chapter is to discuss the results of such studies and, where possible, to interpret these results qualitatively in terms of the basic requirements reported in chapter III. The discussion parallels the three phases of turbojet engine starting: (1) Ignition of the fuel-air mixture (2) Propagation of flame throughout the combustion zone (3) Acceleration of the engine to operating speed.

We derive a new set of equations which describe a continuous one parameter family of expanding wave solutions of the Einstein equations such that the Friedmann universe associated with the pure radiation phase of the Standard Model of Cosmology, is embedded as a single point in this family. All of the spacetime metrics associated with this family satisfy the equation of state $p=\rho c^2/3$, correct for the pure radiation phase after inflation in the Standard Model of the Big Bang. By expanding solutions about the center to leading order in the Hubble length, the family reduces to a one-parameter family of expanding spacetimes that represent a perturbation of the Standard Model. We then derive a co-moving coordinate system in which the perturbed spacetimes can be compared with the Standard Model. In this coordinate system we calculate the correction to the Hubble constant, as well as the exact leading order quadratic correction to the redshift vs luminosity relation for an observer at the center of the expanding FRW spacetime. The leading order correction to the redshift vs luminosity relation entails an adjustable free parameter that introduces an anomalous acceleration. We conclude that any correction to the redshift vs luminosity relation observed after the radiation phase of the Big Bang can be accounted for, at the leading order quadratic level, by adjustment of this free parameter. Since exact non-interacting expanding waves represent possible time-asymptotic wave patterns for conservation laws, we propose to further investigate the possibility that these corrections to the Standard Model might account for the anomalous acceleration of the galaxies, without the introduction of the cosmological constant.

We consider Brans-Dicke theory with a self-interacting potential in Einstein conformal frame. We show that an accelerating expansion is possible in a spatially flat universe for large values of the Brans-Dicke parameter consistent with local gravity experiments.

We examine ion acceleration by irradiating a hundred TW laser pulse on a double-layer target. It is shown analytically and by three-dimensional particle-in-cell simulations that higher energy protons are obtained by using material with a high charge-to-mass ratio in the first layer of a double-layer target, because a strong Coulomb explosion occurs in such a material. As a result, the protons keep accelerating for a longer time. Using the optimal conditions for the target, it is shown that high energy and high quality protons can be generated.

To clarify the relationship between phase-stable acceleration (PSA) and unlimited relativistic acceleration (URA) (Phys. Rev. Lett. 104, 135003 (2010)), an analytical relativistic model is proposed in the interactions of the ultra-intense laser and nanometer foils, based on hydrodynamic equations. The dependence of the ion momentum on time is consistent with the previous results and checked by PIC simulations. Depending on the initial ion momentum, relativistic RPA contains two acceleration processes: phase-stable limited relativistic acceleration (PS-LRA) and URA. In PS-LRA, the potential is a deep well trapping the ions. The ion front, i.e., the bottom, separates it into two parts: the left half region is PSA region; the right half region is PSD region, where the ions climb up and are decelerated to return back. In PS-LRA, the maximum ion energy is limited. If the initial ion momentum large enough, ions will experience a potential downhill and drop into a bottomless abyss, which is called phase-lock-like position. URA is not phase-stable any more. At the phase-lock-like position the ions can obtain unlimited energy gain and the ion density is non-zero. You cannot have both PSA and URA.

We investigate vector contributions to the Lagrangian of $\Lambda_3-$massive gravity in the decoupling limit, the less explored sector of this theory. The main purpose is to understand the stability of maximally symmetric %self-accelerating vacuum solutions. Around self-accelerating configurations, vector degrees of freedom become strongly coupled since their kinetic terms vanish, so their dynamics is controlled by higher order interactions. Even in the decoupling limit, the vector Lagrangian contains an infinite number of terms. We develop a systematic method to covariantly determine the vector Lagrangian at each order in perturbations, fully manifesting the symmetries of the system. We show that, around self-accelerating solutions, the structure of higher order $p$-form Galileons arise, avoiding the emergence of a sixth BD ghost mode. However, a careful analysis shows that there are directions along which the Hamiltonian is unbounded from below. This instability can be interpreted as one of the available fifth physical modes behaving as a ghost. Therefore, we conclude that self-accelerating configurations, in the decoupling limit of $\Lambda_3$-massive gravity, are generically unstable.

In this paper we investigate the impact of the coupling between a quintessence field and clustered matter on the average equation of state of the scalar field. We take the NFW profile to be characteristic of bound structures on galactic and cluster scales, and the isothermal distribution to hold for objects on supercluster scales. Solving analytically for the scalar-field profile, we find that the greatest impact on the equation of state comes from the superclusters. Employing numerical case studies, we verify this effect and probe its dependence on the evolutionary state of the supercluster. An estimate across the Hubble volume yields corrections to the homogeneous equation of state of ~3%, increasing with coupling strength.

Length scales are determined that govern the behavior at small separations of the correlations of fluid-particle acceleration, viscous force, and pressure gradient. The length scales and an associated universal constant are quantified on the basis of published data. The length scale governing pressure spectra at high wave numbers is discussed. Fluid-particle acceleration correlation is governed by two length scales; one arises from the pressure gradient, the other from the viscous force.

We derive the maximum accelerated particle energy from first-order and second-order Fermi acceleration at nonrelativistic and relativistic shocks for explosions taking place in a uniform surrounding medium. Second-order stochastic processes in relativistic flows are shown to be capable of accelerating cosmic rays to ultra-high energies. Cosmic rays above the knee of the cosmic ray spectrum can be accelerated by the second-order Fermi mechanism in relativistic flows, such as those occuring in gamma-ray bursts and unusual supernovae like SN 1998bw.

In this paper we present an investigation of numerical Monte Carlo simulations of the diffusive shock acceleration in the test particle limit. Very high gamma flow astrophysical plasmas, have been used, from $\gamma_{up}$ $\sim50$ up to $\gamma_{up}$ $\sim1000$, which could be relevant to the suggested models of AGNs Jets and their Central Engines as well as the ultra-relativistic shock particle acceleration in Gamma Ray Burst (GRB) fireballs. Particularly the energy gain per shock crossing and the time constant for the above high relativistic processes is numerically calculated. We explicitly find a considerable $\gamma^{2}$ energy boosting in the first shock cycle, and in all subsequent shock cycles the particle energy is multiplied by a large factor. Also a noted acceleration speed-up for the same acceleration process has been observed. Both of those results are connected with theoretical suggestions that a significant enhancement of the acceleration process is possible due to relativistic effects not present at lower plasma flow speeds. The acceleration speed-up and the mean energy-gain per shock cycle found could efficiently justify the theory of the origin of Ultra High Energy Cosmic Rays (UHECR) from the sites of GRBs.

In this paper we present an investigation of numerical Monte Carlo simulations of the diffusive shock acceleration in the test particle limit. Very high gamma flow astrophysical plasmas, have been used, from $\gamma_{up}$ $\sim50$ up to $\gamma_{up}$ $\sim1000$, which could be relevant to the suggested models of AGNs Jets and their Central Engines as well as the ultra-relativistic shock particle acceleration in Gamma Ray Burst (GRB) fireballs. Particularly the energy gain per shock crossing and the time constant for the above high relativistic processes is numerically calculated. We explicitly find a considerable $\gamma^{2}$ energy boosting in the first shock cycle, and in all subsequent shock cycles the particle energy is multiplied by a large factor. Also a noted acceleration speed-up for the same acceleration process has been observed. Both of those results are connected with theoretical suggestions that a significant enhancement of the acceleration process is possible due to relativistic effects not present at lower plasma flow speeds. The acceleration speed-up and the mean energy-gain per shock cycle found could efficiently justify the theory of the origin of Ultra High Energy Cosmic Rays (UHECR) from the sites of GRBs.

We extend de la Fuente and Romero's defining equation for uniform acceleration in a general curved spacetime from linear acceleration to the full Lorentz covariant uniform acceleration. In a flat spacetime background, we have explicit solutions. We use generalized Fermi-Walker transport to parallel transport the Frenet basis along the trajectory. In flat spacetime, we obtain velocity and acceleration transformations from a uniformly accelerated system to an inertial system. We obtain the time dilation between accelerated clocks. We apply our acceleration transformations to the motion of a charged particle in a constant electromagnetic field and recover the Lorentz-Abraham-Dirac equation.

We explore the impact of Fermi-like acceleration of Lyman-alpha (Ly{\alpha}) photons across shock fronts on the observed Ly{\alpha} spectral line shape. We first confirm the result of Neufeld & McKee (1988) that this mechanism gives rise to extended blue wings which may have been observed in some radio galaxies. Our Monte-Carlo radiative transfer calculations further show that in a minor modification of the shell-model, in which we add an additional static shell of hydrogen, this process can naturally explain the small blue bumps observed in a subset of Ly{\alpha} emitting galaxies, which have been difficult to explain with conventional shell-models. Blue bumps can be produced with an additional column density of static hydrogen as small as $N_{HI}^{static} \ll N_{HI}^{shell}$, and typically occur at roughly the outflow velocity of the shell. In our model the spectra of so-called 'blue-bump objects' might reflect an evolutionary stage in which the outflows regulating the escape of Ly{\alpha} photons are still engulfed within a static interstellar medium.

We explore the impact of Fermi-like acceleration of Lyman-alpha (Ly{\alpha}) photons across shock fronts on the observed Ly{\alpha} spectral line shape. We first confirm the result of Neufeld & McKee (1988) that this mechanism gives rise to extended blue wings which may have been observed in some radio galaxies. Our Monte-Carlo radiative transfer calculations further show that in a minor modification of the shell-model, in which we add an additional static shell of hydrogen, this process can naturally explain the small blue bumps observed in a subset of Ly{\alpha} emitting galaxies, which have been difficult to explain with conventional shell-models. Blue bumps can be produced with an additional column density of static hydrogen as small as $N_{HI}^{static} \ll N_{HI}^{shell}$, and typically occur at roughly the outflow velocity of the shell. In our model the spectra of so-called 'blue-bump objects' might reflect an evolutionary stage in which the outflows regulating the escape of Ly{\alpha} photons are still engulfed within a static interstellar medium.

A number of nearby Northern Hemisphere shell-type Supernova Remnants (SNRs) has been observed in TeV gamma rays, but none of them could be detected so far. This failure calls for a critical reevaluation of the theoretical arguments for gamma-ray emission of SNRs. The present paper discusses diffusive shock acceleration in shell-type SNRs in full kinetic theory. Emphasis is also given to the possible problems for VHE gamma-ray production due to the environmental conditions a SN progenitor finds itself in. Observational upper limits are compared with theoretical predictions for the gamma-ray flux. Empirical arguments from the observation of X-ray power law continua for electron-induced Inverse Compton gamma-ray emission at TeV energies are discussed in their relation to the nucleonic Pi-zero decay emission from the same objects. Finally, a point is made for the simplest case of SNe Ia, expected to explode in a uniform circumstellar medium. Here in particular the very recently detected Southern Hemisphere remnant of SN 1006 is compared with Tycho's SNR. On the basis of the assumed parameters for the two remnants SN 1006 is tentatively identified with a remnant whose TeV gamma-ray emission is dominated by Inverse Compton radiation. Tycho might be dominantly a Pi-zero decay gamma-ray source.

Parker's initial insights from 1958 provided a key causal link between the heating of the solar corona and the acceleration of the solar wind. However, we still do not know what fraction of the solar wind's mass, momentum, and energy flux is driven by Parker-type gas pressure gradients, and what fraction is driven by, e.g., wave-particle interactions or turbulence. SOHO has been pivotal in bringing these ideas back to the forefront of coronal and solar wind research. This paper reviews our current understanding of coronal heating in the context of the acceleration of the fast and slow solar wind. For the fast solar wind, a recent model of Alfven wave generation, propagation, and non-WKB reflection is presented and compared with UVCS, SUMER, radio, and in-situ observations at the last solar minimum. The derived fractions of energy and momentum addition from thermal and nonthermal processes are found to be consistent with various sets of observational data. For the more chaotic slow solar wind, the relative roles of steady streamer-edge flows (as emphasized by UVCS abundance analysis) versus bright blob structures (seen by LASCO) need to be understood before the relation between streamer heating and and slow-wind acceleration can be known with certainty. Finally, this presentation summarizes the need for next-generation remote-sensing observations that can supply the tight constraints needed to unambiguously characterize the dominant physics.

A method of numerically evaluating slowly convergent monotone series is described. First, we apply a condensation transformation due to Van Wijngaarden to the original series. This transforms the original monotone series into an alternating series. In the second step, the convergence of the transformed series is accelerated with the help of suitable nonlinear sequence transformations that are known to be particularly powerful for alternating series. Some theoretical aspects of our approach are discussed. The efficiency, numerical stability, and wide applicability of the combined nonlinear-condensation transformation is illustrated by a number of examples. We discuss the evaluation of special functions close to or on the boundary of the circle of convergence, even in the vicinity of singularities. We also consider a series of products of spherical Bessel functions, which serves as a model for partial wave expansions occurring in quantum electrodynamic bound state calculations.

The Sun's relativistic gravitational gradient accelerations of Earth and Moon, dependent on the motions of the latter bodies, act upon the system's internal angular momentum. This spin-orbit force (which plays a part in determining the gravity wave signal templates for astrophysical sources) slightly accelerates the Earth-Moon system as a whole, but it more robustly perturbs that system's internal dynamics with a 5 cm, synodically oscillating range contribution which is presently measured to 4 mm precision by more than three decades of lunar laser ranging.

The dynamics of a relativistic particle in a Reissner-Nordstrom background is studied using Caianiello model with maximal acceleration. The behaviour of the particle, embedded in a new effective geometry, changes with respect to the classical scenario because of the formation of repulsive potential barriers near the horizon. Black hole formation by accretion of massive particles is not therefore a viable process in the model. At the same time, the naked singularity remains largely unaffected by maximal acceleration corrections.

A conventional explanation of the correlation between the Pioneer 10/11 anomalous acceleration and spin-rate change is given. First, the rotational Doppler shift analysis is improved. Finally, a relation between the radio beam reaction force and the spin-rate change is established. Computations are found in good agreement with observational data. The relevance of our result to the main Pioneer 10/11 anomalous acceleration is emphasized. Our analysis leads us to conclude that the latter may not be merely artificial.

We study inflation and late-time acceleration in the expansion of the universe in non-minimal electromagnetism, in which the electromagnetic field couples to the scalar curvature function. It is shown that power-law inflation can be realized due to the non-minimal gravitational coupling of the electromagnetic field, and that large-scale magnetic fields can be generated due to the breaking of the conformal invariance of the electromagnetic field through its non-minimal gravitational coupling. Furthermore, it is demonstrated that both inflation and the late-time acceleration of the universe can be realized in a modified Maxwell-$F(R)$ gravity which is consistent with solar system tests and cosmological bounds and free of instabilities. At small curvature typical for current universe the standard Maxwell theory is recovered. We also consider classically equivalent form of non-minimal Maxwell-$F(R)$ gravity, and propose the origin of the non-minimal gravitational coupling function based on renormalization-group considerations.

The physics of collisionless relativistic shocks with a moderate magnetization is presented. Micro-physics is relevant to explain the most energetic radiative phenomena of Nature, namely that of the termination shock of Gamma Ray Bursts. A transition towards Fermi process occurs for decreasing magnetization around a critical value which turns out to be the condition for the scattering to break the mean field inhibition. Scattering is produced by magnetic micro-turbulence driven by the current carried by returning particles, which had not been considered till now, but turns out to be more intense than Weibel's one around the transition. The current is also responsible for a buffer effect on the motion of the incoming flow, on which the threshold for the onset of turbulence depends.

The physics of collisionless relativistic shocks with a moderate magnetization is presented. Micro-physics is relevant to explain the most energetic radiative phenomena of Nature, namely that of the termination shock of Gamma Ray Bursts. A transition towards Fermi process occurs for decreasing magnetization around a critical value which turns out to be the condition for the scattering to break the mean field inhibition. Scattering is produced by magnetic micro-turbulence driven by the current carried by returning particles, which had not been considered till now, but turns out to be more intense than Weibel's one around the transition. The current is also responsible for a buffer effect on the motion of the incoming flow, on which the threshold for the onset of turbulence depends.

We apply the non-linear diffusive shock acceleration theory in order to describe the properties of two supernova remnants, SN 1572 (Tycho) and SN 1604 (Kepler). By analyzing the multi-wavelength spectra, we infer that both Tycho's and Kepler's forward shocks are accelerating protons up to ~500 TeV, channeling into cosmic rays more than 10 per cent of their kinetic energy. We find that the streaming instability induced by cosmic rays is consistent with the X-ray morphology of the remnants, indicating a very efficient magnetic field amplification (up to ~300 microG). In the case of Tycho we explain the gamma-ray spectrum from the GeV up to the TeV band as due to pion decay produced in nuclear collisions by accelerated nuclei scattering against the background gas. On the other hand, due to the larger distance, the gamma-ray emission from Kepler is not detected, being below the sensitivity of the present detectors, but it should be detectable by the Cerenkov Telescope Array.

We developed a magneto-turbulent model for the cosmic ray (CR) electrons seen in the radio halo clusters of galaxies. Steady state momentum distribution functions of the CR electrons are calculated for given spectra of the turbulent Alfven waves. The radio spectrum produced by the obtained CR electron distribution is compared to the observed radio spectrum of the Coma radio halo. We find that the observed radio spectrum of the Coma cluster is well reproduced when the spectral index of the turbulent Alfven waves is 2.8. The obtained energy spectrum of the turbulent Alfven waves is steeper than that expected from the turbulence theory, suggesting back reaction of the particle acceleration. The fitting procedure constraints the amplitude of the turbulent Alfven waves as well as the spectral index. Then we estimate the dissipation of the turbulent Alfven waves, which is found to be less than the cooling rate by X-ray radiation. We suggest that the turbulence which is sufficient for particle acceleration is developed in the clusters containing the radio halo. It is most likely that cluster mergers create the turbulence and seed relativistic electrons.

Monte Carlo techniques are used to model nonlinear particle acceleration in parallel collisionless shocks of various speeds, including mildly relativistic ones. When the acceleration is efficient, the backreaction of accelerated particles modifies the shock structure and causes the compression ratio, r, to increase above test-particle values. Modified shocks with Lorentz factors less than about 3 can have compression ratios considerably greater than 3 and the momentum distribution of energetic particles no longer follows a power law relation. These results may be important for the interpretation of gamma-ray bursts if mildly relativistic internal and/or afterglow shocks play an important role accelerating particles that produce the observed radiation. For shock Lorentz factors greater than about 10, r approaches 3 and the so-called `universal' test-particle result of N(E) proportional to E^{-2.3} is obtained for sufficiently energetic particles. In all cases, the absolute normalization of the particle distribution follows directly from our model assumptions and is explicitly determined.

Based on the generic acceleration model, which suggests different types of electromagnetic interactions between the cosmic charged particles and the different configurations of the electromagnetic (plasma) fields, the ultra high energy cosmic rays are studied. The plasma fields are assumed to vary, spatially and temporally. The well-known Fermi accelerations are excluded. Seeking for simplicity, it is assumed that the energy loss due to different physical processes is negligibly small. The energy available to the plasma sector is calculated in four types of electromagnetic fields. It has been found that the drift in a time--varying magnetic field is extremely energetic. The energy scale widely exceeds the Greisen-Zatsepin-Kuzmin (GZK) cutoff. The polarization drift in a time--varying electric field is also able to raise the energy of cosmic rays to an extreme value. It can be compared with the Hillas mechanism. The drift in a spatially--varying magnetic field is almost as strong as the polarization drift. The curvature drift in a non--uniform magnetic field and a vanishing electric field is very weak.

The transverse stability of the target is crucial for obtaining high quality ion beams using the laser radiation pressure acceleration (RPA) mechanism. In this letter, a theoretical model and supporting two-dimensional (2D) Particle-in-Cell (PIC) simulations are presented to clarify the physical mechanism of the transverse instability observed in the RPA process. It is shown that the density ripples of the target foil are mainly induced by the coupling between the transverse oscillating electrons and the quasi-static ions, a mechanism similar to the transverse two stream instability in the inertial confinement fusion (ICF) research. The predictions of the mode structure and the growth rates from the theory agree well with the results obtained from the PIC simulations in various regimes, indicating the model contains the essence of the underlying physics of the transverse break-up of the target.

A continuous process of creation of particles is investigated as a possible connection between the inflationary stage with late cosmic acceleration. In this model, the inflationary era occurs due to a continuous and fast process of creation of relativistic particles, and the recent accelerating phase is driven by the non-relativistic matter creation from the gravitational field acting on the quantum vacuum, which finally results in an effective equation of state less than $-1$. Thus, explaining recent results in favor of a phantom dynamics without the need of any modifications in the gravity theory has been proposed. Finally, we confront the model with recent observational data of type Ia Supernova, history of the Hubble parameter, baryon acoustic oscillations, and the cosmic microwave background.

Theory of the first-order Fermi acceleration of cosmic ray particles at relativistic shock waves is reviewed. We consider shocks with parallel and oblique, sub- and super-luminal magnetic field configurations and with finite-amplitude magnetic field perturbations. A role of oblique field configurations and field perturbations in forming the cosmic ray energy spectrum and changing the acceleration time scale is discussed.

We briefly report on the recently proposed [G. Fiore, R. Fedele, U. de Angelis, Phys. Plasmas 21 (2014), 113105], [G. Fiore, S. De Nicola, arXiv:1509.04656] electron acceleration mechanism named "slingshot effect": under suitable conditions the impact of an ultra-short and ultra-intense laser pulse against the surface of a low-density plasma is expected to cause the expulsion of a bunch of superficial electrons with high energy in the direction opposite to that of the pulse propagation; this is due to the interplay of the huge ponderomotive force, huge longitudinal field arising from charge separation, and the finite size of the laser spot.

Solar flares accelerate both ions and electrons to high energies, and their X-ray and gamma-ray signatures not only probe the relationship between their respective acceleration, but also allow for the measurement of accelerated and ambient abundances. RHESSI observations have shown a striking close linear correlation of gamma-ray line fluence from accelerated ions greater than approximately 20 MeV and bremsstrahlung emission from relativistic accelerated electrons greater than 300 keV, when integrated over complete flares, suggesting a common acceleration mechanism. SMM/GRS observations, however, show a weaker correlation, and this discrepancy might be associated with previously observed electron-rich episodes within flares and/or temporal variability of gamma-ray line fluxes over the course of flares. We use the latest RHESSI gamma-ray analysis techniques to study the temporal behavior of the RHESSI flares, and determine what changes can be attributed to an evolving acceleration mechanism or to evolving abundances. We also discuss possible explanations for changing abundances.

ephemeral objects - A/V set for Acceleration Radio - aired live on CFRO 100.5FM from 11pm-12am, 2023-12-21

Methods for providing stereoscopic image presentation and stereoscopic configurations using stereoscopic viewing systems having converged or parallel cameras may be set up to reduce or eliminate erroneously perceived accelerations and decelerations by proper selection of parameters, such as an image magnification factor, q, and intercamera distance, 2w. For converged cameras, q is selected to be equal to Ve - qwl = 0, where V is the camera distance, e is half the interocular distance of an observer, w is half the intercamera distance, and l is the actual distance from the first nodal point of each camera to the convergence point, and for parallel cameras, q is selected to be equal to e/w. While converged cameras cannot be set up to provide fully undistorted three-dimensional views, they can be set up to provide a linear relationship between real and apparent depth and thus minimize erroneously perceived accelerations and decelerations for three sagittal planes, x = -w, x = 0, and x = +w which are indicated to the observer. Parallel cameras can be set up to provide fully undistorted three-dimensional views by controlling the location of the observer and by magnification and shifting of left and right images. In addition, the teachings of this disclosure can be used to provide methods of stereoscopic image presentation and stereoscopic camera configurations to produce a nonlinear relation between perceived and real depth, and erroneously produce or enhance perceived accelerations and decelerations in order to provide special effects for entertainment, training, or educational purposes.

A summary of the proceedings from the workshop are presented. The areas covered were solar activity, solar wind, terrestrial effects, and solar acceleration. Specific topics addressed include: (1) solar cycle manifestations, both large and small scale, as well as long-term and short-term changes, including transients such as flares; (2) sources of solar wind, as identified by interplanetary observations including coronal mass ejections (CME's) or x-ray bright points, and the theory for and evolution of large-scale and small-scale structures; (3) magnetosphere responses, as observed by spacecraft, to variable solar wind and transient energetic particle emissions; and (4) origin and propagation of solar cosmic rays as related to solar activity and terrestrial effects, and solar wind coronal-hole relationships and dynamics.

That particles may be accelerated by vacuum effects in quantum field theory has been repeatedly proposed in the last few years. A natural upshot of this is a mechanism for cosmic rays (CR) primaries acceleration. A mechanism for acceleration by the zero-point field (ZPE) when the ZPE is taken in a realistic sense (in opposition to a virtual field) was considered. Originally the idea was developed within a semiclassical context. The classical Einstein-Hopf model (EHM) was used to show that free isolated electromagnrtically interacting particles performed a random walk in phase space and more importantly in momentum space when submitted to the perennial action of the so called classical electromagnrtic ZPE.

The acceleration of electrons by the Fermi-Parker mechanisms in a quasistationary turbulent plasma of dimension l, mean magnetic field strength B, and mean number density n are considered. The electrons suffer radiative and ionization losses and have a scattering mean free path that increases linearly with their momentum. Analytic solutions for the steady-state electron energy spectra are presented. The spectra are characterized by an exponential cutoff above a given momentum determined by the synchrontron or the confinement time, depending on the physical characteristics of the accelerating region.

Helicopter flight acceleration/deceleration maneuvers are quantified and put to use in the fields of handling qualities, flight training and evaluation of simulator fidelity. The three specific cases include the normal speed change maneuver, the nap-of-the-Earth dash/quickstop, and the decelerating approach to hover. All of these maneuvers share common generic features in terms of pilot adaptation and mathematical description; yet each differs in terms of the essential feedback loop structure, implications for handling qualities requirements, and simulator fidelity criteria.

Countermeasures for reduction in work capacity (maximal oxygen uptake and strength) during spaceflight and enhanced orthostatic intolerance during re-entry, landing and egress from the return vehicle are continuing problems. The purpose for this study was to test the hypothesis that passive-acceleration training; supine, interval, exercise plus acceleration training and exercise combined with acceleration training would improve orthostatic tolerance in ambulatory men; and that addition of the aerobic exercise conditioning would not alter this improved tolerance from that of passive-acceleration training. Seven men (24-38 yr) underwent "Passive" training on the Ames human-powered centrifuge (HPC) for 30 min, "Exercise" training on the cycle ergometer with constant +Gz acceleration; and "Combined" exercise training at 40% to 90% of the HPC +Gz(max) exercise level. Maximal supine exercise loads increased significant (P

Ion acceleration driven by superintense laser pulses is attracting an impressive and steadily increasing effort. Motivations can be found in the potential for a number of foreseen applications and in the perspective to investigate novel regimes as far as available laser intensities will be increasing. Experiments have demonstrated in a wide range of laser and target parameters the generation of multi-MeV proton and ion beams with unique properties such as ultrashort duration, high brilliance and low emittance. In this paper we give an overview of the state-of-the art of ion acceleration by laser pulses as well as an outlook on its future development and perspectives. We describe the main features observed in the experiments, the observed scaling with laser and plasma parameters and the main models used both to interpret experimental data and to suggest new research directions.

A new model of accelerating expansion of the universe is presented. A de Sitter solution in vacuum and a exact solution with the dust mater source are obtained. A new explanation of the acceleration of the cosmic expansion is given. In is proved that the changing of the expansion from decelerating to accelerating is an intrinsic property of the universe without need of dark energy.