Electroweak vacuum stability in the Higgs-Dilaton theory

We study the stability of the Electroweak (EW) vacuum in a scale-invariant extension of the Standard Model and General Relativity, known as a Higgs-Dilaton theory. The safety of the EW vacuum against possible transition towards another vacuum is a necessary condition for the model to be phenomenologically acceptable. We find that, within a wide range of parameters of the theory, the decay rate is significantly suppressed compared to that of the Standard Model. We also discuss properties of a tunneling solution that are specific to the Higgs-Dilaton theory.Comment: 16 pages, 5 figure

Q-holes

We consider localized soliton-like solutions in the presence of a stable scalar condensate background. By the analogy with classical mechanics, it can be shown that there may exist solutions of the nonlinear equations of motion that describe dips or rises in the spatially-uniform charge distribution. We also present explicit analytical solutions for some of such objects and examine their properties.Comment: 17 pages, 11 figures, LaTeX. v3: minor corrections in the tex

Lev Perovsky and the “Emerald of Kokovin”

Поступила в редакцию: 07.01.2023. Принята к печати: 06.04.2023.Submitted: 07.01.2023. Accepted: 06.04.2023.В 1835 г. ревизор Л. Ф. Ярошевицкий обнаружил в квартире командира Екатеринбургской гранильной фабрики Я. В. Коковина большое количество неучтенных драгоценных и полудрагоценных камней. В их числе находился крупный изумруд, который, по словам ревизора, «едва не превосходил достоинством изумруд, бывший в короне Юлия Цезаря». Камни были запакованы в ящики, опечатаны и отправлены в Санкт-Петербург. При вскрытии ящиков в столице выяснилось, что указанный изумруд бесследно исчез. Поиски драгоценного камня остались без результата. В изданных в 1961 г. «Очерках по истории камня» академика А. Е. Ферсмана похитителем изумруда был назван вице-президент Департамента уделов и владелец крупной коллекции минералов Л. А. Перовский. Ради обоснования этой версии был искажен текст донесения Л. Ф. Ярошевицкого. Под именем «изумруда Коковина» в собрании Минералогического музея им. А. Е. Ферсмана РАН хранился другой уральский минерал. Нет уверенности и в том, что автором версии был сам А. Е. Ферсман, потому что академик умер в 1945 г., оставив второй том «Очерков» незавершенным. Авторитет имени академика А. Е. Ферсмана и популярность его «Очерков» (последний раз были переизданы в 2003 г.) поныне способствуют тиражированию необоснованной версии о виновности Л. А. Перовского в краже «изумруда Коковина». Целью настоящей статьи является обеление имени «ревностного любителя минералогии», как называл Льва Перовского известный германский минералог Густав Розе.In 1835, auditor L. F. Yaroshevitsky discovered many unaccounted precious and semiprecious stones in the apartment of Ya. V. Kokovin, the commander of the Ekaterinburg Lapidary Factory. Among them was a large emerald, which, according to the auditor, “almost surpassed the dignity of the emerald in the crown of Julius Caesar”. The stones were packed in boxes, sealed, and sent to St Petersburg. After the boxes were opened in the capital, it turned out that the specified emerald had disappeared without a trace. The search for the gem remained fruitless. In the Essays on the History of Stone published in 1961 by academic A. E. Fersman, L. A. Perovsky, the vice-president of the Appanage Department and owner of a large collection of minerals was claimed to have stolen the emerald. For the sake of substantiating this version, the text of L. F. Yaroshevitsky’s report was distorted. Under the name of the “Emerald of Kokovin”, another Ural mineral got into the collection of the Fersman Mineralogical Museum of the Russian Academy of Sciences. There is also no certainty that the author of the version was A. E. Fersman himself, because the academic died in 1945, leaving the second volume of Essays unfinished. The authority of academic A. E. Fersman and the popularity of his Essays (last reprinted in 2003) still contribute to the replication of the unfounded version of L. A. Perovsky’s stealing the “Emerald of Kokovin”. The purpose of this article is to justify the name of the “zealous lover of mineralogy”, as the famous German mineralogist prof. Gustav Rose called Lev Perovsky

In situ synthesis, structural chemistry and vibrational spectroscopy of Zn-doped Ca5Mg4(VO4)6

The phase formation of the solid solution Ca5Mg4–xZnx(VO4)6 (0≤x≤4) was studied in situ using differential scanning calorimetry and high-temperature X-Ray powder diffraction (XRPD). XRPD analysis shows the appearance of unavoidable secondary pyrovanadate phases using conventional synthesis methods. The local structure of the solid solution was verified by vibrational spectroscopy. The analysis of the infrared and Raman spectroscopy data allows establishing the main features between vanadate garnets and their isostructural analogs among natural silicates

Synthesis of solid solutions of vanadates Ca5Mg4-xCOxV6O24 and Ca5-Mg4-xNixV6O24

This work gives an overview of first time synthesised solid solutions with the cubic 4 ̅3 structure Ca5Mg4-xCOxV6O24 and Ca5-Mg4-xNixV6O24, where is x=0÷4. Melting points of these compounds are estimated by method of differential scanning calorimetry. Studied samples exhibit mixed type electrical conductivity.Впервые синтезированы твердые растворы ванадатов с кубической структурой 4 ̅3 Ca5Mg4-xCOxV6O24 и Ca5-Mg4-xNixV6O24, где x=0÷4. Определены температуры плавления полученных составов методом дифференциальной сканирующей калориметрии. Исследуемые соединения обладают смешанной электронно-ионной электропроводностью