A brief biography of Hans Albrecht Bethe the Doctor Honoris Causa – Bethe was born in Strasbourg, Alsace-Lorraine, on 2 July 1906. His father was Prof. Albrecht Bethe, an expert in the psychology of the University ever upset over the treatment of the Nazis when Adolf Hitler became Chancellor of Germany in January 1933.
When teens Bethe likes mathematics and physics. However, while in College, she chose physics because he thinks a mathematical equation is intended to prove things that are real. He studied physics in Frankfurt am Main and completed his education at the University of Munich with a Ph.d. in 1928.
Bethe through dark while serving as an Assistant Professor at the University of Tubingen. He was discharged in disrespect in 1933 by the Nazis in power then because her mother was Jewish, but he considers himself not a descendant of Jews.
The incident makes it very hated the Nazis. And the hatred it made him accept the invitation of j. Robert Oppenheimer from the United States to join the Manhattan Project, a United States military project to design a bomb.
Bethe left for the United States to design a bomb was accompanied by Rose Ewald, daughter of P.P. Ewald, an expert in x-ray physics then he married in 1939 and gave him two children, namely Henry and Monika.
Over the project given in the Government of the United States gave him the post of Assistant Professor at Cornell University in 1934. In 1941, he officially became a citizen of the United States.
Hans Albrecht Bethe studied nuclear physics at Cornell University who took him to his success in the Manhattan Project. After succeeding in the project, he returned to Cornell University and continued his studies of the nuclear reactions.
Bethe became known as the first scientist to successfully explain the energy levels of atoms in the hydrogen spectrum reported by Willis Lamb in 1947 in a Physics Conference. In 1948, Bethe had contributed important papers on the origin of the chemical elements at the moment of the big bang.
Paper stacking Bethe along with Ralph Alpher and Gamow Georges is known for its paper “Alpha-Betha-Gamow.”
Also, Bethe also developed the Bohr’s theory about the essence of the fertilization a more quantitative way. This research, as well as the knowledge that there has been nuclear theory and know the results of his experiments, embodied in three articles published in Reviews of Modern Physics, which over the years became mandatory grip (called the Bethe’s Bible) for the physicists who wrestles in the nuclear field.
In 1949, Edward Teller, Bethe invites to join in making business superbomb (hydrogen bomb). But Bethe refused and opposed the action. He also campaigned for the use of anti-nuclear violence.
In 1958, he led a scientific adviser to the United States at a meeting in Geneva, Switzerland, which discusses setting the ban on nuclear tests. He also participated in the negotiations with the Soviet Union in 1963 and became an advisor to President Eisenhower to prohibit the testing of nuclear weapons.
In 1992, at the age of 86 years, Bethe wrote an open letter to all scientists to boycott the development of nuclear weapons and other weapons of mass destruction such as chemical weapons and biological weapons.
In 1997 despite being aged 91 years, Bethe wrote a letter to President Clinton to stop the flow of funds for all types of nuclear weapons testing, including experiments aimed at developing nuclear weapons.
Bethe continued to call for anti-nuclear use for violence to the world. This earned him an award as doctor honoris causa from universities around the world.
Apart from the award, achievement of Bethe was his success in developing the theory of nuclear reactions that produce energy star (stellar nucleosynthesis). The discovery of these nuclear reactions led him to reach for the Nobel Prize in Physics in 1967.
Hans Albrecht Bethe died in his house Itacha, New York, United States on March 5, 2005.
About the theory of the Bethe, nuclear fusion and nuclear fission
Bethe successfully developed the theory of nuclear reactions that produce energy star. He found that the reaction that occurs in stars that are relatively light follow turnarounds of carbon-nitrogen-oxygen, known as Bethe-Weizsacker Cyle. In the meantime, that occurs in the Sun and stars fainter is a proton-proton reaction.
In nuclear physics, a nuclear reaction is a process in which two nucleus or particle nuclear collided to produce different results from the initial product. There are two kinds of nuclear reaction, namely: nuclear fusion reaction and the reaction of nuclear fission.
The nuclear fusion reaction is the reaction of the fusion of two or more atomic nuclei into recently and produces energy, also known as a clean reaction. Nuclear fusion reaction also produces x-ray radiation alpha, beta, and gamma are very dangerous to humans. Items that are frequently used in nuclear fusion reactions is lithium and hydrogen (especially lithium-6, deuterium, tritium).
Fusion reactions between deuterium and lithium-6 that generates two atoms of helium-4. The reaction that occurs in the Sun as it does on the hydrogen bomb, that fusion reactions (the merger). Another case with a nuclear bomb through the reaction of fission (splitting). Scientists believe that the Sun with fusion reaction can generate powerful energy.
The reaction that occurs in the Sun is the fusion reactions with the process of a merger between the hydrogen atoms generate helium atoms with huge energy results. The Sun is estimated to have a diameter of approximately 1.4 million km and has a mass of about 32,000 Earth masses.
The temperature of the Sun on the surface of about 6000 degrees C and a core of approximately 20 million degrees C, with at most 70% hydrogen and 27% helium. The heat that we receive on Earth is the result of a reaction that occurs in the Sun. The Sun is like a hot stove and radiates energy in all directions, including the Earth.
The Sun does not radiate energy periodically, but constantly because the reaction that occurs in the Sun is a chain reaction. This means that each energy fusion happened to produce energy and other unstable atoms.
The energy generated is then created destruction of material and produce energy. While the unstable atoms decay into a stable element, which then reacts again with fusion protons, so there arose another element that is not stable and energy. And so on without stopping.
These reactions lead to the loss of mass of the Sun due to the process of the destruction of the material (mass defects). This formulation by Einstein’s famous formulation, namely: E = Mc2, where E is energy, m is mass arises is missing, and C is the speed of light in a vacuum.
Chain reaction cycles expressed by Bethe and Weizsacker is often called Helium Hydrogen synthesis. The core of this process is the burning of four hydrogen nuclei into helium nuclei. In this process happen more or less 0.75% reduction of hydrogen mass is converted into energy.
The scientists calculated that the emissivity of the Sun roughly 3.78 x 1033 erg/sec. Using a formulation of Einstein. We can determine the mass is gone from the Sun every second, which is about million tons.
All the achievements and activities of the Bethe made him remembered as Dean of physics throughout the world. Although excellent, Bethe is not pretentious and not just think of himself. According to his friend “Bethe is a remarkable combination of a truly great scientist who has also made major contributions in the public service of his nation.”