The evolution of relative frequencies of ONe and CO SNe Ia

In this population synthesis work we study a variety of possible origin channels of supernovae type Ia (SNe Ia) Among them mergers of carbon-oxygen (CO) and oxygen-neon (ONe) white dwarfs (WDs) under the influence of gravitational waves are considered as the primary channel of SNe Ia formation. We estimated frequencies of mergers of WDs with different chemical compositions and distributions of masses of merging WDs. We computed the dependence of the ratio of merger frequencies of ONe and CO WDs as primaries in corresponding binaries on time. The scatter of masses of considered sources (up to the factor $1.5-2$) of SNe Ia is important and should be carefully studied with other sophisticated methods from theoretical point of view. Our ``game of parameters'' potentially explains the increased dimming of SNe Ia in the redshift range $z\approx 0.5-1$ by the changes in the ratio of ONe and CO WDs, i.e., to describe the observed accelerated expansion of the Universe in terms of the evolution of properties of SNe Ia instead of cosmological explanations. This example shows the extreme importance of theoretical studies of problems concerning SNe Ia, because evolutionary scenario and parameter games in nature potentially lead to confusions in their empirical standardization and, therefore, they can influence on cosmological conclusions.Comment: MNRAS, accepted, 12 pages, 4 figures, 1 tabl

Public Discussion around American Purchases for Needs of Russian Roads during First World War

The problem of the dependence of Russian railway transport on foreign supplies during the First World War is considered. For the first time, this issue is revealed through the prism of a public discussion, which was conducted on the pages of the Russian periodical press on the issues of American procurement for railways. Particular attention is paid to criticism of the current situation in the field of railway transport, the danger of dependence of the Russian industry on foreign powers (both hostile, neutral and allied) and the need for import substitution. New sources are introduced into scientific circulation (materials of the periodical press, transcripts of meetings of the State Duma), which make it possible to get a more complete picture of both the problems that have developed in the field of railway transport and their perception in Russian society. It is noted that despite the positive attitude of the press to the establishment of commercial and industrial relations with America, many publicists and politicians noted that the replacement of German capital and industrial goods with American ones posed no less danger for Russia in the future, which could only be avoided through the development of national production