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Isaac F Silvera - One of the best experts on this subject based on the ideXlab platform.
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phases of the Hydrogen isotopes under pressure Metallic Hydrogen
Advances in Physics: X, 2021Co-Authors: Isaac F Silvera, Ranga DiasAbstract:Hydrogen is the simplest molecule in nature. One of the key problems and challenges in condensed matter physics is to understand the phases, properties, and structure of Hydrogen as a function of p...
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finite element simulation of the liquid liquid transition to Metallic Hydrogen
Physical Review B, 2019Co-Authors: Matthew Houtput, J Tempere, Isaac F SilveraAbstract:Hydrogen at high temperature and pressure undergoes a phase transition from a liquid molecular phase to a conductive atomic state, or liquid Metallic Hydrogen, sometimes referred to as the plasma phase transition (PPT). The PPT phase line was observed in a recent experiment studying laser-pulse heated Hydrogen in a diamond anvil cell in the pressure range $\ensuremath{\sim}100\ensuremath{-}170$ GPa for temperatures up to $\ensuremath{\sim}2000\phantom{\rule{0.28em}{0ex}}\mathrm{K}$. The experimental signatures of the transition are (i) a negative pressure-temperature slope, (ii) a plateau in the heating curve, assumed to be related to the latent heat of transformation, and (iii) an abrupt increase in the reflectance of the sample. We present a finite-element simulation that accurately takes into account the position and time dependence of the heat deposited by the laser pulse. We calculate the heating curves and the sample reflectance and transmittance. This simulation confirms that the observed plateaus are related to the phase transition; however, we find that large values of latent heat are needed and may indicate that dynamics at the transition are more complex than considered in current models. Finally, experiments are proposed that can distinguish between a change in optical properties due to a transition to a Metallic state or due to closure of the band gap in molecular Hydrogen.
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striking isotope effect on the metallization phase lines of liquid Hydrogen and deuterium
Physical Review B, 2018Co-Authors: Mohamed Zaghoo, R J Husband, Isaac F SilveraAbstract:Liquid atomic Metallic Hydrogen is the simplest, lightest, and most abundant of all liquid metals. The role of nucleon motions or ion dynamics has been somewhat ignored in relation to the dissociative insulator-metal transition. Almost all previous experimental high-pressure studies have treated the fluid isotopes, Hydrogen and deuterium, with no distinction. Studying both Hydrogen and deuterium at the same density, most crucially at the phase transition line, can experimentally reveal the importance of ion dynamics. We use static compression to study the optical properties of dense deuterium in the pressure region of 1.2-1.7 Mbar and measured temperatures up to ~3000 K. We observe an abrupt increase in reflectance, consistent with dissociation-induced metallization, at the transition. Here we show that at the same pressure (density) for the two isotopes, the phase line of this transition reveals a prominent isotopic shift, ~700 K. This shift is lower than the isotopic difference in the free-molecule dissociation energies, but it is still large considering the high density of the liquid and the complex many-body effects. Our work reveals the importance of quantum nuclear effects in describing the metallization transition and conduction properties in dense Hydrogen systems at conditions of giant planetary interiors, and provides an invaluable benchmark for ab-initio calculations.
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conductivity and dissociation in liquid Metallic Hydrogen and implications for planetary interiors
Proceedings of the National Academy of Sciences of the United States of America, 2017Co-Authors: Mohamed Zaghoo, Isaac F SilveraAbstract:Liquid Metallic Hydrogen (LMH) is the most abundant form of condensed matter in our solar planetary structure. The electronic and thermal transport properties of this Metallic fluid are of fundamental interest to understanding Hydrogen’s mechanism of conduction, atomic or pairing structure, as well as the key input for the magnetic dynamo action and thermal models of gas giants. Here, we report spectrally resolved measurements of the optical reflectance of LMH in the pressure region of 1.4–1.7 Mbar. We analyze the data, as well as previously reported measurements, using the free-electron model. Fitting the energy dependence of the reflectance data yields a dissociation fraction of 65 ± 15%, supporting theoretical models that LMH is an atomic Metallic liquid. We determine the optical conductivity of LMH and find Metallic Hydrogen’s static electrical conductivity to be 11,000–15,000 S/cm, substantially higher than the only earlier reported experimental values. The higher electrical conductivity implies that the Jovian and Saturnian dynamo are likely to operate out to shallower depths than previously assumed, while the inferred thermal conductivity should provide a crucial experimental constraint to heat transport models.
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response to comment on observation of the wigner huntington transition to Metallic Hydrogen
Science, 2017Co-Authors: Isaac F Silvera, Ranga DiasAbstract:Goncharov and Struzhkin present comments on our observation of Metallic Hydrogen. We show that most of their comments are unfounded and that our observation of a transition to a shiny, high-reflectance phase remains as evidence that Hydrogen has transformed to the Metallic phase.
David M Ceperley - One of the best experts on this subject based on the ideXlab platform.
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high temperature superconductivity in atomic Metallic Hydrogen
Physical Review B, 2011Co-Authors: Jeffrey M Mcmahon, David M CeperleyAbstract:Superconductivity in the recently proposed ground-state structures of atomic Metallic Hydrogen is investigated over the pressure range 500 GPa to 3:5 TPa. Near molecular dissociation, the electron{phonon coupling and renormalized Coulomb repulsion are similar to the molecular phase. A continuous increase in the critical temperature Tc with pressure is therefore expected, to 356K near 500 GPa. As the atomic phase stabilizes with increasing pressure, increases, causing Tc to approach 481K near 700 GPa. At the rst atomic{atomic structural phase transformation
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high temperature superconductivity in atomic Metallic Hydrogen
Physical Review B, 2011Co-Authors: Jeffrey M Mcmahon, David M CeperleyAbstract:Superconductivity in the recently proposed ground-state structures of atomic Metallic Hydrogen is calculated over the pressure range 500 GPa to $3.5$ TPa. Near molecular dissociation, the electron-phonon coupling $\ensuremath{\lambda}$ and renormalized Coulomb repulsion are similar to the molecular phase. A nearly continuous increase in the critical temperature ${T}_{c}$ with pressure is thus predicted in this range, to $\ensuremath{\sim}356$ K near 500 GPa. As the atomic phase stabilizes with increasing pressure, $\ensuremath{\lambda}$ increases, causing ${T}_{c}$ to approach 481 K near 700 GPa. At the first atomic-atomic structural phase transformation near 1--$1.5$ TPa, a discontinuous jump in $\ensuremath{\lambda}$ occurs, causing ${T}_{c}$ to increase up to 764 K.
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ground state structures of atomic Metallic Hydrogen
Physical Review Letters, 2011Co-Authors: Jeffrey M Mcmahon, David M CeperleyAbstract:: Ab initio random structure searching using density functional theory is used to determine the ground-state structures of atomic Metallic Hydrogen from 500 GPa to 5 TPa. Including proton zero-point motion within the harmonic approximation, we estimate that molecular Hydrogen dissociates into a monatomic body-centered tetragonal structure near 500 GPa (r(s)=1.23) that remains stable to 1 TPa (r(s)=1.11). At higher pressures, Hydrogen stabilizes in an …ABCABC… planar structure that is similar to the ground state of lithium, but with a different stacking sequence. With increasing pressure, this structure compresses to the face-centered cubic lattice near 3.5 TPa (r(s)=0.92).
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equation of state of Metallic Hydrogen from coupled electron ion monte carlo simulations
Physical Review E, 2010Co-Authors: Miguel A Morales, Carlo Pierleoni, David M CeperleyAbstract:We present a study of Hydrogen at pressures higher than molecular dissociation using the coupled electron-ion Monte Carlo method. These calculations use the accurate reptation quantum Monte Carlo method to estimate the electronic energy and pressure while doing a Monte Carlo simulation of the protons. In addition to presenting simulation results for the equation of state over a large region of the phase diagram, we report the free energy obtained by thermodynamic integration. We find very good agreement with density-functional theory based molecular-dynamics calculations for pressures beyond 600 GPa and densities above $\ensuremath{\rho}=1.4\text{ }\text{g}/{\text{cm}}^{3}$, both for thermodynamic and structural properties. This agreement provides a strong support to the different approximations employed in the density-functional treatment of the system, specifically the approximate exchange-correlation potential and the use of pseudopotentials for the range of densities considered. We find disagreement with chemical models, which suggests that a reinvestigation of planetary models\char22{}previously constructed using the Saumon-Chabrier-Van Horn equations of state\char22{}might be needed.
Burkhard Militzer - One of the best experts on this subject based on the ideXlab platform.
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ab initio free energy calculations of the solubility of silica in Metallic Hydrogen and application to giant planet cores
The Astrophysical Journal, 2014Co-Authors: Felipe Gonzalezcataldo, Hugh F Wilson, Burkhard MilitzerAbstract:By combining density functional molecular dynamics simulations with a thermodynamic integration technique, we determine the free energy of Metallic Hydrogen and silica, SiO2, at megabar pressures and thousands of degrees Kelvin. Our ab initio solubility calculations show that silica dissolves into fluid Hydrogen above 5000 K for pressures from 10 and 40 Mbars, which has implications for the evolution of rocky cores in giant gas planets like Jupiter, Saturn, and a substantial fraction of known extrasolar planets. Our findings underline the necessity of considering the erosion and redistribution of core materials in giant planet evolution models, but they also demonstrate that hot Metallic Hydrogen is a good solvent at megabar pressures, which has implications for high-pressure experiments.
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solubility of iron in Metallic Hydrogen and stability of dense cores in giant planets
The Astrophysical Journal, 2013Co-Authors: S M Wahl, Hugh F Wilson, Burkhard MilitzerAbstract:The formation of the giant planets in our solar system, and likely a majority of giant exoplanets, is most commonly explained by the accretion of nebular Hydrogen and helium onto a large core of terrestrial-like composition. The fate of this core has important consequences for the evolution of the interior structure of the planet. It has recently been shown that H2O, MgO, and SiO2 dissolve in liquid Metallic Hydrogen at high temperature and pressure. In this study, we perform ab initio calculations to study the solubility of an innermost Metallic core. We find dissolution of iron to be strongly favored above 2000 K over the entire pressure range (0.4-4 TPa) considered. We compare with and summarize the results for solubilities on other probable core constituents. The calculations imply that giant planet cores are in thermodynamic disequilibrium with surrounding layers, promoting erosion and redistribution of heavy elements. Differences in solubility behavior between iron and rock may influence evolution of interiors, particularly for Saturn-mass planets. Understanding the distribution of iron and other heavy elements in gas giants may be relevant in understanding mass-radius relationships, as well as deviations in transport properties from pure Hydrogen-helium mixtures.
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solubility of water ice in Metallic Hydrogen consequences for core erosion in gas giant planets
The Astrophysical Journal, 2012Co-Authors: Hugh F Wilson, Burkhard MilitzerAbstract:Using ab initio simulations we investigate whether water ice is stable in the cores of giant planets, or whether it dissolves into the layer of Metallic Hydrogen above. By Gibbs free energy calculations we find that for pressures between 10 and 40 Mbar the ice-Hydrogen interface is thermodynamically unstable at temperatures above approximately 3000 K, far below the temperature of the core-mantle boundaries in Jupiter and Saturn. This implies that the dissolution of core material into the fluid layers of giant planets is thermodynamically favored, and that further modeling of the extent of core erosion is warranted.
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erosion of icy cores in giant gas planets
arXiv: Earth and Planetary Astrophysics, 2010Co-Authors: Hugh F Wilson, Burkhard MilitzerAbstract:Using ab initio simulations we investigate whether water ice is stable in the cores of giant planets, or whether it dissolves into the layer of Metallic Hydrogen above. By Gibbs free energy calculations we find that for pressures between 10 and 40 Mbar the ice-Hydrogen interface is unstable at temperatures above approximately 3000 K, far below the temperature of the core-mantle boundaries in Jupiter and Saturn that are of the order of 10000 K. This implies that the cores of solar and extrasolar giant planets are at least partially eroded.
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erosion of icy cores in giant gas planets
AGUFM, 2010Co-Authors: Hugh F Wilson, Burkhard MilitzerAbstract:Using abinitio simulations we investigate whether water ice is stable in the cores of giant planets, or whetherit dissolves into the layer of Metallic Hydrogen above. By Gibbs free energy calculations we find that forpressures between 10 and 40 Mbar the ice-Hydrogen interface is unstable at temperatures above approximately3000 K, far below the tempeature of the core-mantle boundaries in Jupiter and Saturn that are of the orderof 10000 K. This implies that the cores of solar and extrasolar giant planets are at least partially eroded.According to the core accretion hypothesis [1], giantgas planets such as Jupiter and Saturn formed via the ac-cumulation of an protocore of rock and ice which gainedsolid material until it reached sufficient size to begin ac-creting the gaseous component of the protosolar nebula.Giant planets thus consist of primarily Hydrogen-heliumouter layers surrounding a solid core of rock and ice. Itis unknown, however, whether such a core remains stablefollowing the accretion of the fluid outer layer or whetherit dissolves and erodes into the surrounding fluid layers[2, 3]. The gravitational moments of Jupiter and Saturn,which have been measured by prior planetary missionsand will be determined with high accuracy for Jupiterby the upcoming Juno mission, may be used in combi-nation with interior models [3–6] to estimate the mass ofthe present-day core. It is unclear whether these massescorrespond to the primordial core mass, and it has beensuggested [3, 5] that the present-day core mass of Jupitermay be insufficient to explain its formation by core ac-cretion within the relatively short lifetime of the proto-solar nebula [7], however a more recent Jupiter model [6]predicted a larger core of 14–18 Earth masses which isconsistent with core accretion. Direct measurements ofJupiter’s atmosphere also suggest a significant enhance-ment in the concentration of heavy (Z > 3) elements[8], but it is not known to what extent this should beattributed to a large flux of late-arriving planetesimalsversus the upwelling of core material. Determining theextent of core erosion is thus a major priority for under-standing the interiors of giant planets and the process bywhich they were formed.In this Letter we focus on water ice, as one of the mostprevalent and volatile core materials, and consider thequestion of whether it is soluble in fluid Metallic hydro-gen at the core-mantle boundaries of giant planets. Wa-ter ice is the most prevalent of the planetary ices (water,methane and ammonia) which may be assumed to makeup the outermost layers of a differentiated rock-ice core[9]. Assuming the existence of a core-mantle boundary atwhich water ice and fluid Hydrogen are in direct contact,the relevant question is whether such a boundary is ther-modynamically stable or whether the system may lowerits Gibbs free energy by the redistribution of the H andO atoms of the ice phase into the fluid Hydrogen. The ex-treme pressure and temperature conditions prevalent atgiant planet core-mantle boundaries (8000–12000K and8–18Mbarfor Saturn, 18000–21000Kand 35–45Mbar forJupiter) are not yet obtainable in the laboratory, thus abinitio simulations provide the best available guide to theconditions under which dissolution of icy cores may beexpected to occur.To determine the solubility behaviour of ice in H weused density functional molecular dynamics (DFT-MD)and coupling constant integration (CCI) techniques tocompute the Gibbs free energy of solvation, ∆G
N. W. Ashcroft - One of the best experts on this subject based on the ideXlab platform.
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structures and potential superconductivity in sih 4 at high pressure en route to Metallic Hydrogen
Physical Review Letters, 2006Co-Authors: Ji Feng, Aitor Bergara, Wojciech Grochala, Tomasz Jaron, Roald Hoffmann, N. W. AshcroftAbstract:A way to circumvent the high pressures needed to metallize Hydrogen is to ``precompress'' it in Hydrogen-rich molecules, a strategy probed theoretically for silane. We show that phases with tetrahedral ${\mathrm{SiH}}_{4}$ molecules should undergo phase transitions with sixfold- and eightfold-coordinate Si appearing above 25 GPa. The most stable structure found can be metallized at under a megabar and at a compression close to the prediction of Goldhammer-Herzfeld criterion. According to a BCS-like estimate, Metallic silane should be a high-temperature superconductor.
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a superconductor to superfluid phase transition in liquid Metallic Hydrogen
Nature, 2004Co-Authors: Asle Sudbo, Egor Babaev, N. W. AshcroftAbstract:Although Hydrogen is the simplest of atoms, it does not form the simplest of solids or liquids. Quantum effects in these phases are considerable (a consequence of the light proton mass) and they ha ...
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Hydrogen dominant Metallic alloys: High temperature superconductors?
Physical Review Letters, 2004Co-Authors: N. W. AshcroftAbstract:The arguments suggesting that Metallic Hydrogen, either as a monatomic or paired metal, should be a candidate for high temperature superconductivity are shown to apply with comparable weight to alloys of Metallic Hydrogen where Hydrogen is a dominant constituent, for example, in the dense group IVa hydrides. The attainment of Metallic states should be well within current capabilities of diamond anvil cells, but at pressures considerably lower than may be necessary for Hydrogen.
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high temperature superconductivity in Metallic Hydrogen electron electron enhancements
Physical Review Letters, 1997Co-Authors: C F Richardson, N. W. AshcroftAbstract:We investigate the possibility of superconductivity in a dense phase of Hydrogen which becomes Metallic while retaining diatomic character. Correlated fluctuations between electrons and holes in the ensuring band-overlap state can lead to significant enhancements in the transition temperature (compared with monatomic phases) principally through a reduction in the associated Coulomb pseudopotential. The effective electron-electron interaction is determined by a method which treats electrons and phonons on an equivalent footing, an approach which confirms that monatomic phases also remain candidates for high temperature superconductivity. {copyright} {ital 1996} {ital The American Physical Society}
Pierre-marie Robitaille - One of the best experts on this subject based on the ideXlab platform.
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on solar granulations limb darkening and sunspots brief insights in remembrance of father angelo secchi
viXra, 2013Co-Authors: Pierre-marie RobitailleAbstract:Father Angelo Secchi used the existence of solar granulation as a central line of reasoning when he advanced that the Sun was a gaseous body with a photosphere containing incandescent particulate matter (Secchi A. Sulla Struttura della Fotosfera Solare. Bullettino Meteorologico dell’Osservatorio del Collegio Romano, 30 November 1864, v.3(11), 1–3). Secchi saw the granules as condensed matter emitting the photospheric spectrum, while the darkened intergranular lanes conveyed the presence of a gaseous solar interior. Secchi also considered the nature of sunspots and limb darkening. In the context of modern solar models, opacity arguments currently account for the emissive properties of the photosphere. Optical depth is thought to explain limb darkening. Both temperature variations and magnetic fields are invoked to justify the weakened emissivities of sunspots, even though the presence of static magnetic fields in materials is not usually associated with modified emissivity. Conversely, within the context of a liquid Metallic Hydrogen solar model, the appearance of granules, limb darkening, and sunspots can be elegantly understood through the varying directional emissivity of condensed matter. A single explanation is applicable to all three phenomena. Granular contrast can be directly associated with the generation of limb darkening. Depending on size, granules can be analyzed by considering Kolmogoroff’s formulations and Benard convection, respectively, both of which were observed using incompressible liquids, not gases. Granules follow the 2-dimensional space filling laws of Aboav-Weiner and Lewis. Their adherence to these structural laws provides supportive evidence that the granular surface of the Sun represents elements which can only be constructed from condensed matter. A gaseous Sun cannot be confined to a 2-dimensional framework. Mesogranules, supergranules, and giant cells constitute additional entities which further support the idea of a condensed Sun. With respect to sunspots, the decrease in emissivity with increasing magnetic field strength lends powerful observational support to the idea that these structures are comprised of liquid Metallic Hydrogen. In this model, the inter-atomic lattice dimensions within sunspots are reduced. This increases the density and Metallic character relative to photospheric material, while at the same time decreasing emissivity. Metals are well known to have lowered directional emissivities with respect to non-metals. Greater Metallicity produces lower emissivity. The idea that density is increased within sunspots is supported by helioseismology. Thus, a liquid Metallic Hydrogen model brings with it many advantages in understanding both the emissivity of the solar surface and its vast array of structures. These realities reveal that Father Secchi, like Herbert Spencer and Gustav Kirchhoff, was correct in his insistence that condensed matter is present on the photosphere. Secchi and his contemporaries were well aware that gases are unable to impart the observed structure.
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commentary on the liquid Metallic Hydrogen model of the sun insight relative to coronal holes sunspots and solar activity
viXra, 2013Co-Authors: Pierre-marie RobitailleAbstract:While mankind will always remain unable to sample the interior of the Sun, the presence of sunspots and coronal holes can provide clues as to its subsurface structure. Insight relative to the solar body can also be gained by recognizing that the Sun must exist in the condensed state and support a discrete lattice structure, as required for the production of its continuous spectrum. In this regard, the layered liquid Metallic Hydrogen lattice advanced as a condensed model of the Sun (Robitaille P.M. Liquid Metallic Hydrogen: A Building Block for the Liquid Sun. Progr. Phys., 2011, v. 3, 60–74; Robitaille P.M. Liquid Metallic Hydrogen II: A Critical Assessment of Current and Primordial Helium Levels in Sun. Progr. Phys., 2013, v. 2, 35–47; Robitaille J.C. and Robitaille P.M. Liquid Metallic Hydrogen III. Intercalation and Lattice Exclusion Versus Gravitational Settling and Their Consequences Relative to Internal Structure, Surface Activity, and Solar Winds in the Sun. Progr. Phys., 2013, v. 2, in press) provides the ability to add structure to the solar interior. This constitutes a significant advantage over the gaseous solar models. In fact, a layered liquid Metallic Hydrogen lattice and the associated intercalation of non-Hydrogen elements can help to account for the position of sunspots and coronal holes. At the same time, this model provides a greater understanding of the mechanisms which drive solar winds and activity.
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forty lines of evidence for condensed matter the sun on trial liquid Metallic Hydrogen as a solar building block
PrPh, 2013Co-Authors: Pierre-marie RobitailleAbstract:Our Sun has confronted humanity with overwhelming evidence that it is comprised of condensed matter. Dismissing this reality, the standard solar models continue to be anchored on the gaseous plasma. In large measure, the endurance of these theories can be attributed to 1) the mathematical elegance of the equations for the gaseous state, 2) the apparent success of the mass-luminosity relationship, and 3) the long-lasting influence of leading proponents of these models. Unfortunately, no direct physical finding supports the notion that the solar body is gaseous. Without exception, all observations are most easily explained by recognizing that the Sun is primarily comprised of condensed matter. However, when a physical characteristic points to condensed matter, a postori arguments are invoked to account for the behavior using the gaseous state. In isolation, many of these treatments appear plausible. As a result, the gaseous models continue to be accepted. There seems to be an overarching belief in solar science that the problems with the gaseous models are few and inconsequential. In reality, they are numerous and, while often subtle, they are sometimes daunting. The gaseous equations of state have introduced far more dilemmas than they have solved. Many of the conclusions derived from these approaches are likely to have led solar physics down unproductive avenues, as deductions have been accepted which bear little or no relationship to the actual nature of the Sun. It could be argued that, for more than 100 years, the gaseous models have prevented mankind from making real progress relative to understanding the Sun and the universe. Hence, the Sun is now placed on trial. Forty lines of evidence will be presented that the solar body is comprised of, and surrounded by, condensed matter. These ‘proofs’ can be divided into seven broad categories: 1) Planckian, 2) spectroscopic, 3) structural, 4) dynamic, 5) helioseismic, 6) elemental, and 7) earthly. Collectively, these lines of evidence provide a systematic challenge to the gaseous models of the Sun and expose the many hurdles faced by modern approaches. Observational astronomy and laboratory physics have remained unable to properly justify claims that the solar body must be gaseous. At the same time, clear signs of condensed matter interspersed with gaseous plasma in the chromosphere and corona have been regrettably dismissed. As such, it is hoped that this exposition will serve as an invitation to consider condensed matter, especially Metallic Hydrogen, when pondering the phase of the Sun.
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the liquid Metallic Hydrogen model of the sun and the solar atmosphere iv on the nature of the chromosphere
viXra, 2013Co-Authors: Pierre-marie RobitailleAbstract:The chromosphere is the site of weak emission lines characterizing the flash spectrum observed for a few seconds during a total eclipse. This layer of the solar atmosphere is known to possess an opaque Hemission and a great number of spicules, which can extend well above the photosphere. A stunning variety of Hydrogen emission lines have been observed in this region. The production of these lines has provided the seventeenth line of evidence that the Sun is comprised of condensed matter (Robitaille P.M. Liquid Metallic Hydrogen II: A critical assessment of current and primordial helium levels in Sun. Progr. Phys., 2013, v. 2, 35-47). Contrary to the gaseous solar models, the simplest mechanism for the production of emission lines is the evaporation of excited atoms from condensed surfaces existing within the chromosphere, as found in spicules. This is reminiscent of the chemiluminescence which occurs during the condensation of silver clusters (Konig L., Rabin I., Schultze W., and Ertl G. Chemiluminescence in the Agglomeration of Metal Clusters. Science, v. 274, no. 5291, 1353-1355). The process associated with spicule formation is an exothermic one, requiring the transport of energy away from the site of condensation. As atoms leave localized surfaces, their electrons can occupy any energy level and, hence, a wide variety of emission lines are produced. In this regard, it is hypothesized that the presence of hydri des on the Sun can also fa- cilitate Hydrogen condensation in the chromosphere. The associated line emission from main group and transition elements constitutes the thirtie th line of evidence that the Sun is condensed matter. Condensation processes also help to explain why spicules manifest an apparently constant temperature over their entire lengt h. Since the corona supports magnetic field lines, the random orientations associated wi th spicule formation suggests that the Hydrogen condensates in the chromosphere are not Metallic in nature. Spicules provide a means, not to heat the corona, but rather, for condensed Hydrogen to rejoin the photospheric layer of the Sun. Spicular velocities of fo rmation are known to be essentially independent of gravitational effects and highly supportive of the hypothesis that true condensation processes are being observed. The presence of spicules brings into question established chromospheric densities and provides additional support for condensation processes in the chromosphere, the seventh line of evidence that the Sun is comprised of condensed matter. In order to explain the occurrence of the dark lines in the solar spectrum, we must assume that the solar atmosphere incloses a luminous nucleus, producing a continuous spectrum, the brightness of which ex- ceeds a certain limit. The most probable supposi- tion which can be made respecting the Sun's consti- tution is, that it consists of a solid or liquid nucleus, heated to a temperature of the brightest whiteness, surrounded by an atmosphere of somewhat lower temperature.
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the liquid Metallic Hydrogen model of the sun and the solar atmosphere vii further insights into the chromosphere and corona
Progress in Physics, 2013Co-Authors: Pierre-marie RobitailleAbstract:In the liquid Metallic Hydrogen model of the Sun, the chromosphere is responsible for the capture of atomic Hydrogen in the solar atmosphere and its eventual re-entry onto the photospheric surface (P.M. Robitaille. The Liquid Metallic Hydrogen Model of the Sun and the Solar Atmosphere IV. On the Nature of the Chromosphere. Prog. Phys., 2013, v. 3, L15–L21). As for the corona, it represents a diffuse region containing both gaseous plasma and condensed matter with elevated electron affinity (P.M. Robitaille. The Liquid Metallic Hydrogen Model of the Sun and the Solar Atmosphere V. On the Nature of the Corona. Prog. Phys., 2013, v. 3, L22–L25). Metallic Hydrogen in the corona is thought to enable the continual harvest of electrons from the outer reaches of the Sun, thereby preserving the neutrality of the solar body. The rigid rotation of the corona is offered as the thirty-third line of evidence that the Sun is comprised of condensed matter. Within the context of the gaseous models of the Sun, a 100 km thick transition zone has been hypothesized to exist wherein temperatures increase dramatically from 10–10 K. Such extreme transitional temperatures are not reasonable given the trivial physical scale of the proposed transition zone, a region adopted to account for the ultra-violet emission lines of ions such as C IV, O IV, and Si IV. In this work, it will be argued that the transition zone does not exist. Rather, the intermediate ionization states observed in the solar atmosphere should be viewed as the result of the simultaneous transfer of protons and electrons onto condensed Hydrogen structures, CHS. Line emissions from ions such as C IV, O IV, and Si IV are likely to be the result of condensation reactions, manifesting the involvement of species such as CH4, SiH4, H3O in the synthesis of CHS in the chromosphere. In addition, given the presence of a true solar surface at the level of the photosphere in the liquid Metallic Hydrogen model, it follows that the great physical extent of the chromosphere is supported by gas pressure, much like the atmosphere of the Earth. This constitutes the thirty-fourth line of evidence that the Sun is comprised of condensed matter.