An Adjustable Cleft Based on an 8‐sulfonamide‐2‐naphthoic Acid with Oxyanion Hole Geometry

The reduction of several o,o'-dihydroxyazo-compounds is studied by means of pulse polarographic techniques (DPP, NPP and RPP). The compounds studied are the following: 2-(2'-hydroxyphenylazo)-phenol (o,o'-dihydroxyazobenzene), 1-(2'-hydroxy-1'-naphthylazo)-2-naphthol-4-sulphonic acid (calcon or Eriochrome Blue Black R), 1-(2'-hydroxy-4'-sulpho-1'-naphthylazo)-2-hydroxy-3-naphthoic acid (calcon carboxylic acid), and 1-(1'-hydroxy-2'-naphthylazo)-6-nitro-2-naphthol-4-sulphonic acid (Eriochrome Black T). Correlations between Ip and Epand experimental variables (pH, T, conc.) and instrumental parameters (dropping time, t, and pulse magnitude, ΔE) are established. Reaction mechanisms formerly proposed are discussed on the basis of the new obtained results, and the ranges are defined where adsorption and/or acid-base catalysis are operative.

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Islands and stretched horizon

Journal of High Energy Physics ◽

10.1007/jhep07(2021)051 ◽

2021 ◽

Vol 2021 (7) ◽

Author(s):

Yoshinori Matsuo

Keyword(s):

Black Holes ◽

Black Hole ◽

Hawking Radiation ◽

Entanglement Entropy ◽

Total System ◽

Island Rule ◽

Asymptotically Flat ◽

Flat Spacetime ◽

Ads Spacetime ◽

Hole Geometry

Abstract Recently it was proposed that the entanglement entropy of the Hawking radiation contains the information of a region including the interior of the event horizon, which is called “island.” In studies of the entanglement entropy of the Hawking radiation, the total system in the black hole geometry is separated into the Hawking radiation and black hole. In this paper, we study the entanglement entropy of the black hole in the asymptotically flat Schwarzschild spacetime. Consistency with the island rule for the Hawking radiation implies that the information of the black hole is located in a different region than the island. We found an instability of the island in the calculation of the entanglement entropy of the region outside a surface near the horizon. This implies that the region contains all the information of the total system and the information of the black hole is localized on the surface. Thus the surface would be interpreted as the stretched horizon. This structure also resembles black holes in the AdS spacetime with an auxiliary flat spacetime, where the information of the black hole is localized at the interface between the AdS spacetime and the flat spacetime.

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Uptunneling to de Sitter

Journal of High Energy Physics ◽

10.1007/jhep09(2020)070 ◽

2020 ◽

Vol 2020 (9) ◽

Author(s):

Mehrdad Mirbabayi

Keyword(s):

Black Holes ◽

Black Hole ◽

False Vacuum ◽

De Sitter ◽

Dimensional Theory ◽

Hole Geometry ◽

Horizon Geometry ◽

Two Sides ◽

Extremal Black Holes

Abstract We propose a Euclidean preparation of an asymptotically AdS2 spacetime that contains an inflating dS2 bubble. The setup can be embedded in a four dimensional theory with a Minkowski vacuum and a false vacuum. AdS2 approximates the near horizon geometry of a two-sided near-extremal Reissner-Nordström black hole, and the two sides can connect to the same Minkowski asymptotics to form a topologically nontrivial worm- hole geometry. Likewise, in the false vacuum the near-horizon geometry of near-extremal black holes is approximately dS2 times 2-sphere. We interpret the Euclidean solution as describing the decay of an excitation inside the wormhole to a false vacuum bubble. The result is an inflating region inside a non-traversable asymptotically Minkowski wormhole.

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Studies on the Synthesis of Highly Substituted Naphthol: Preparation of 6-Hydroxy-5,7-dimethoxy-2-naphthoic Acid, Isolated from Ulmus Thomasii

Journal of Chemical Research Synopses ◽

10.1039/a803651i ◽

1998 ◽

pp. 638-639 ◽

Cited By ~ 2

Author(s):

Claudio Fuganti ◽

Stefano Serra

Keyword(s):

Naphthoic Acid

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A UV complete picture of black hole conforming to low energy effective field theory

International Journal of Modern Physics A ◽

10.1142/s0217751x18502196 ◽

2018 ◽

Vol 33 (36) ◽

pp. 1850219

Author(s):

Biplab Paik

Keyword(s):

Field Theory ◽

Black Hole ◽

Effective Field Theory ◽

Effective Field ◽

Radiation Process ◽

Quantum Black Hole ◽

Classical Geometry ◽

Characteristic Radius ◽

Hole Geometry ◽

Principle Of Causality

In this paper, we propose a UV complete, quantum improved picture of a black hole geometry that conforms to the IR gravity of effective field theory. Our work builds on identifying an effective space-distributed notion of black hole fluid in quantum improved regular Einstein gravity and its theoretical correspondence with a cosmology inspired power law fluctuation of matter. Hence, we make use of phenomenological asymptotic scales of matter fluctuation in static space to consequently derive a UV complete line-element of black hole space–time. In this appraisal, it gets explicit how principle of causality is preserved even while there is an effective spread of black hole fluid across horizon(s). Gravity changes from its conventional classical geometry-state to a quantum masked profile across a hypersurface of characteristic radius [Formula: see text]. We make analyses that probe the newly proposed quantum improved gravity in the contexts of regularity of Einstein fields, complete predictability of Hawking radiation process, and first law of black hole thermodynamics. It emerges that quantum black hole geometry self-regulates a regular timelike core that is abide by every quantum theoretical constraint while being flat around its center.

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