Animation showing the formation of an ultra-dense galaxy: the giant host galaxy disrupts the smaller galaxy, removing its fluffy outer parts, and the dense center is left behind. The animation then zooms in to a possible embedded planet and supermassive black hole.
The Multiperiodic Pulsating Star Y Cam A as a Musical Instrument
In this study we generate musical chords from the oscillation frequencies of the primary component of oscillating eclipsing Algol system Y Cam. The parameters and the procedure of the musical chord generation process from the stellar oscillations are described in detail. A musical piece is also composed in appropriate scale for Y Cam A by using the generated chords from the results of the asteroseismic analysis of the stellar data. The music scores and the digital sound files are provided for both the generated chords and the musical composition. Our study shows that the further orchestral compositions can be made from the frequency analysis results of several pulsating stars by using the procedure stated in present study.
Read more at http://arxiv.org/pdf/1507.07307v1.pdf
Kevin Krisciunas, Don Carona
Using CCD observations of a candle flame situated at a distance of 338 m and calibrated with observations of Vega, we show that a candle flame situated at ~2.6 km (1.6 miles) is comparable in brightness to a 6th magnitude star with the spectral energy distribution of Vega. The human eye cannot detect a candle flame at 10 miles or further, as some statements on the web suggest…
Read more at http://arxiv.org/ftp/arxiv/papers/1507/1507.06270.pdf
Henrique M. Oliveira, Luís V. Melo
The synchronization of two pendulum clocks hanging from a wall was first observed by Huygens during the XVII century. This type of synchronization is observed in other areas, and is fundamentally different from the problem of two clocks hanging from a moveable base.
We present a model explaining the phase opposition synchronization of two pendulum clocks in those conditions. The predicted behaviour is observed experimentally, validating the model.
…Read more at www.nature.com
While dry Coulombic friction is an elementary topic in any standard introductory course in mechanics, the critical distinction between the kinetic and static friction forces is something that is both hard to teach and to learn.
In this paper, I describe a geometric model of static friction that may help introductory students to both understand and apply the Coulomb static friction approximation….
Read more at http://arxiv.org/pdf/1507.04015v1.pdf
Part of a 1929 prediction by physicist Hermann Weyl—of a kind of massless particle that features a singular point in its energy spectrum called the “Weyl point,”—has finally been confirmed by direct observation for the first time, says an international team of physicists led by researchers at MIT. The finding could lead to new kinds of high-power single-mode lasers and other optical devices, the team says.
For decades, physicists thought that the subatomic particles called neutrinos were, in fact, the massless particles that Weyl had predicted—a possibility that was ultimately eliminated by the 1998 discovery that neutrinos do have a small mass. While thousands of scientific papers have been written about the theoretical particles, until this year there had seemed little hope of actually confirming their existence.
“Every single paper written about Weyl points was theoretical, until now,” says Marin Soljači, a professor of physics at MIT and the senior author of a paper published this week in the journal Science confirming the detection. (Another team of researchers at Princeton University and elsewhere independently made a different detection of Weyl particles; their paper appears in the same issue of Science)….
… Read more at: http://phys.org/news/2015-07-weyl-years.html#jCp
Exotic subatomic particle confirmed at Large Hadron Collider after earlier false sightings.
An exotic particle made up of five quarks has been discovered a decade after experiments seemed to rule out its existence.
The short-lived ‘pentaquark’ was spotted by researchers analysing data on the decay of unstable particles in the LHCb experiment at the Large Hadron Collider (LHC) at CERN, Europe’s particle-physics laboratory near Geneva. The finding, says LHCb spokesperson Guy Wilkinson, opens a new era in physicists’ understanding of the strong nuclear force that holds atomic nuclei together.
“The pentaquark is not just any new particle — it represents a way to aggregate quarks, namely the fundamental constituents of ordinary protons and neutrons, in a pattern that has never been observed before,” he says. “Studying its properties may allow us to understand better how ordinary matter, the protons and neutrons from which we’re all made, is constituted.”….