358 research outputs found
Reply to Comment on "Acoustics of tachyon Fermi gas"
In a paper appearing in this issue of Physical Review D, Burmistrov raises
some critical comments on the thermodynamics of a cold tachyon Fermi gas [E.
Trojan and G. V. Vlasov, Phys. Rev. D 83, 124013 (2011)]. However, apart from
any possible theoretical speculation, there are the basic physical principles
to test the theory.Comment: 4 pages, 1 suppl. figur
Acoustics of tachyon Fermi gas
We consider a Fermi gas of free tachyons as a continuous medium and find
whether it satisfies the causality condition. There is no stable tachyon matter
with the particle density below critical value and the Fermi momentum
that depends on the tachyon mass . The pressure
and energy density cannot be arbitrary small, but the situation is
not forbidden. Existence of shock waves in tachyon gas is also discussed. At
low density the tachyon matter remains stable but no shock wave
do survive.Comment: 14 pages, 2 figures (color
Tachyonic thermal excitations and causality
We consider an ideal Fermi gas of tachyonic thermal excitations as a
continuous medium and establish when it satisfies the causality condition. At
high temperature the sound speed is always subluminal , but there is no
stable form of tachyon matter below the critical temperature that
depends on the tachyon mass . The pressure and energy density cannot
be arbitrary small, but can exceed , and when .Comment: 11 pages, 4 figure
Shock waves in superconducting cosmic strings: growth of current
Intrinsic equations of motion of superconducting cosmic string may admit
solutions in the shock-wave form that implies discontinuity of the current term
\chi. The hypersurface of discontinuity propagates at finite velocity
determined by finite increment \Delta \chi =\chi_+ -\chi_-. The current
increases \chi_+>\chi_- in stable shocks but transition between spacelike (\chi
>0) and timelike (\chi<0) currents is impossible.Comment: 13 pages, 3 figure
Проблема гендерної рівності в науці: досягнення та виклики (Problem of gender equality in science: achievements and challenges)
У статті проаналізовано заходи, спрямовані на впровадження
гендерної
рівності
в
науковій
галузі
з
метою
повнішого
використання
інтелектуального
потенціалу
жінок-учених.
Підсумовано
основні досягнення на цьому шляху, визначено
напрямки, на яких необхідно зосередити подальші зусилля як у
сфері наукових досліджень, так і в управлінській науковій і соціальній
сферах.
Наголошено
на
важливості
досвіду
західних
країн
з
гендерної
політики
для
України.
На
підставі
результатів
аналізу
участі
обох
гендерних
груп
науковців
у
програмах
Державного
фонду
фундаментальних досліджень за 2015 р,
обґрунтовано необхідність підвищення наукової активності
українських жінок-вчених. (The measures for the implementation of gender equality in the
scientific sector to more fully use the intellectual potential of women
scientists
were
analysed.
The
main
achievements
in
this
direction were summed up, and the directions in which it is necessary to
focus further efforts both in research and in management science
and social spheres were identified. For several decades it was carried
out
a
large
number
of
measures
to
more
fully
explore
the
possibilities
of using the intellectual potential of the female half of
humanity and gender equality in science, which is the main area
of implementation of educational knowledge and which progress
provides economic and social development of society. An increase
in the participation of women in all fields of scientific research,
and the average attainment of the degree of Doctor of Philosophy
confidently approaching gender parity as in 28 countries of
the European Union, US and Canada; significant progress over
the last two decades reached also in attracting women to the fields
of Science, Physics and Mathematics profile, such as geological,
engineering, computer science, economics, chemistry and physics.
It was found that the inclusion of the gender dimension in the process
of
acquiring
knowledge
changes
their
quality,
efficiency
and
structure
of research and, therefore science is not gender neutral.
The new strategy documents for the EU 2016-2019 years
stressed that the issue of gender equality remains important in all
areas of modern politics of this structure. In the field of research
and innovation policy it is planned to solve this problem by supporting
the program «Horizon – 2020» through cooperation and
research organizations of member countries within the European
Research Area. This identified three focus areas, namely gender
equality in scientific careers, gender balance in decision-making
and the integration of gender approach in research and innovation
ADAPTATION OF QGIS TOOLS IN HIGH SCHOOL GEOGRAPHY EDUCATION
In the last decades, geography teachers have been trying to figure out how to adopt GIS (Geographic Information Systems) tools for their high school classes. Predominantly, teachers have come to use commercial versions. Lately, it has been QGIS getting more attention, especially in environments where teachers do not have access to sufficient funding. Nevertheless, there is a lack of ample research results and available teaching materials for geography teachers that want to give QGIS in their lessons a go. This paper presents our attempt to bridge this gap. We have set several goals in our search for the possibilities of adopting QGIS tools for high school geography lessons. The main one was to learn about the strategies that students have when they are learning about QGIS. Furthermore, we wanted to know what knowledge the students would demonstrate after attending a short course on QGIS basics and if their learning strategies during the lectures would impact their results. To find out, we created a set of 10 lessons and tested most of them on students from a high school in Brno, Czech Republic. The results of two pilot studies show that our research has not ended and that further investigation needs to be made about the circumstances that can affect a successful adaptation of QGIS tools in high school geography education
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