Albert Einstein (1879-1955)

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Albert Einstein

 

SOURCES

1. http://www.pbs.org/wnet/hawking/html/home.html


Background

March 14, 1879 born in Ulm, South Germany, the 1st son of 21 yr old mom Pauline. Dad named Hermann. Religion: Israelitic. Ancestors described as true Swabians. Dad’s side: 2 centuries in Buchau.

Student in Zurich, then Prague, then Berlin. Later in life? Princeton.

1902        He and “Lieserl” Mileva Maric have a daughter on June 22nd in Novi Sad.  Has a job with the Patent office in Bern, Switzerland.

1903        Jan 6: marries Mileva in Bern. Their daughter remains in Novi Sad. In September Lieserl is adopted by strangers.

1904        Their son Hans Albert born in Bern May 14th

1955          April 13: Aneurysm ruptures

April 18: dies, cremated – scattered?

The 20th-century answer to Isaac Newton, Albert Einstein revolutionized our concepts of space and time and developed the theories used to build models of the universe. He was born in Ulm, Germany, though his family moved to Munich shortly thereafter. He showed little academic promise as a teenager, and didn’t begin to make his mark until he moved to Zurich, Switzerland. Working as a patent clerk in Berne in the first years of the new century, he was able to spend his spare time studying physics.

Einstein’s great year was 1905, when he produced three papers of tremendous significance. One gave a mathematical description of the random motions of tiny particles. A second described the photoelectric effect, in which electrons are emitted when light falls on certain metals. (Many people are surprised to learn that he won the Nobel Prize for this description and not for his theories of relativity.) The third paper of the year was on special relativity, in which he described the physics of objects moving at constant velocities and discovered the equivalence of mass and energy as related by the equation E=mc2. It took Einstein 10 more years to develop his general theory of relativity, which describes the universe as a whole and forms the basis for our understanding of the structure of the universe.

E=mc2

The most famous of Einstein’s equations, E=mc2 says that energy (E) and mass (m) are equivalent. In other words, mass can be converted to energy and vice versa. The conversion factor is the speed of light (c) squared, an enormous number when you consider that the speed of light itself is a whopping 186,000 miles per second.

This means that a small amount of matter can be transformed into a huge amount of energy. That’s the secret of stars, where high temperatures and densities permit lighter atoms to fuse into heavier ones. Each heavy atom weighs less than the combined weight of the lighter atoms that formed it, and that difference in mass becomes the energy that keeps stars shining. The process also works in reverse: Energy can be transformed into mass. Cosmologists think that’s how the matter in the universe arose—in the first second following the Big Bang, photons of incredible energy collided with one another, creating pairs of particles and antiparticles.

“The biggest blunder of my life,” as Einstein later called it, the cosmological constant represents a hypothetical force of repulsion. When Einstein developed his general theory of relativity in 1915, he realized that the original equations required the universe to be in motion. He accepted the belief of his time, however, that the universe was static. So he invented the cosmological constant to balance the force of gravity, allowing galaxies to remain at fixed distances. In retrospect, it seems surprising that no one suspected the universe was expanding. But belief that the universe was static—neither expanding nor contracting—apparently had as powerful a grip on scientist’s minds at the time as did the idea among the Greeks, centuries earlier, that planets must move in circular paths.

Einstein didn’t perceive the cosmological constant as a “blunder” until Edwin Hubble showed that all the galaxies are receding from one another, a result Einstein might have predicted had he believed his original equations. Once the genie was out of the bottle, however, it’s been difficult to put back in. Many physicists continue to use the constant because it allows more freedom in building models of the universe.

Gravity

Einstein envisioned gravity as a curvature of space-time caused by the matter in it, as opposed to Newton’s idea of a force acting at a distance. Although objects try to move through space-time in straight lines, this warpage makes their paths appear bent

 

Einstein's Gravity

 

The force that keeps us all glued to the surface of Earth, gravity dominates any discussion of the evolution and fate of the universe. Surprisingly, for all of its impact, it ranks as the weakest of the four fundamental forces in nature (the others being the electromagnetic and strong and weak nuclear forces). But the others pale when you talk about the universe as a whole because the two nuclear forces act only over very short distances, while most large objects are electrically neutral and therefore unaffected by the electromagnetic force.

Isaac Newton first described gravity and had the insight to realize that the force that holds us to Earth (and makes apples fall) is the same one that keeps the planets in their orbits around the Sun. He deduced the mathematical nature of the mutual force and correctly hypothesized that gravity acts across the entire universe. Albert Einstein modified this view of gravity by arguing that the gravitational force is a manifestation of the curvature of space-time. Although Einstein’s idea is necessary for describing the evolution of the universe as a whole, Newton’s theory works well enough when gravitational forces are not extremely strong.