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Heavily pure brown dwarf has been discovered!

Researchers discovered a celestial body heavy brown dwarf, “SDSS J 0104 + 1535”, which is about 750 light years away from the earth.

If the brown dwarf is a celestial body larger than the planet, it could not cause nuclear fusion by light hydrogen. A new observation by the VLT at the European Southern Observatory in Chile revealed details of this object.

If SDSS J0104 + 1535 is predicted to be 10 billion years old, its mass is about 90 times that of Jupiter. However, the sun has a mass that is 1050 times that of Jupiter. SDSS J 0104 + 1535 is much lighter so it could not continue nuclear fusion.

Also, the constituent materials excluding hydrogen and helium is only 0.01%. This also makes it clear that SDSS J 0104 + 1535 is the most “pure” brown dwarf.

Zeng Hua Zhang, who is the Association of Astronomical Physics of the Canary Islands said, surprisingly commented that he discovered such pure brown dwarf. We may also find such a very heavy brown dwarf in near future.

An excellent female physicist who missed the Nobel Prize

Lise Meitner (1878 – 1968)
She was born in Vienna, Austria, as the third of eight children of a Jewish family.

It was hard for female to go and study in higher education at that time, so she decided to be a French teacher after high school. However, she could not give up studying at a university.

Fortunately, the social environment encouraged women to go to Universities then. Lise took the exam and entered the University of Vienna in 1901. She was major in physics and studied under Ludwig Boltzmann.

She went to The University of Berlin in 1907 to study under Max Planck. Then, she found a research job with the chemist Otto Hahn. Lise and he started studying radioactivity, with her insight of physics and his ability of chemistry. In 1918, they discovered the element protactinium.

In 1934, Lise was fascinated with the paper proposing nuclear fusion by Enrico Fermi, and she wanted Hahn to work on this experiment together. The project started, but Hahn had to dismiss Lise later due to political pressure from Nazi Party.

After that, Hahn observed an unexpected result from an experiment, but he was not sure to explain this. Then, he consulted Lise about the result. Lise and her nephew (physicist) proved that it was the nuclear fission.

Unfortunately, Lise Meitner did not get awarded Nobel Prize for the series of experiments, but she surely played an important role in finding nuclear fission.

Discrete dynamics and its applications to our daily lives

Math, physics, engineering, and our lives are closely related. Physics formulates the nature’s motion with mathematics. This provides applications to creating a convenient system for our living.

Let us introduce a two dimensional discrete mapping:
x_(n+1) = 0.6x + y + 5.2/(1.0 + x^2)
y_(n+1) = -0.9999x
The plot is shown as a picture above.

The above equation is a mathematical example, but such model can be used to analyze population growth, radioactive decay, pollution control, medication dosages, robotics, etc.