Goresan Pena

Cleopatra was the daughter of the pharaoh (ruler) of Egypt. In 51 bc, when Cleopatra was 17 or 18, her father died. Cleopatra and her 12-year-old brother became the rulers of Egypt. Three years later, her brother declared that he should be the only ruler. He forced Cleopatra to leave Egypt.

Cleopatra started putting together an army to fight her brother. But before war began, Roman general Julius Caesar arrived in Egypt. Cleopatra decided to ask Caesar for help. But how was she going to get back into Egypt, past her brother’s guards? She came up with a clever plan. Her servants rolled her into a carpet, and delivered it as a gift to Caesar. When the carpet was unrolled, out stepped Cleopatra.

Cleopatra’s plan succeeded. Caesar helped Cleopatra defeat her brother. She was again Egypt’s queen.

Caesar fell in love with Cleopatra. When Caesar returned to Rome, Cleopatra visited him there. Caesar promised that the Roman army would not invade Egypt. Then in 44 bc, Caesar was murdered, and Cleopatra returned to Egypt.

After her return, Cleopatra ruled Egypt without interference for several years. In 41 bc, however, Roman general Mark Antony demanded that Cleopatra meet with him.

Cleopatra was in a difficult situation. She knew that the powerful Roman army could invade Egypt at any time. Cleopatra agreed to meet with Antony, but surprised him by arriving on a magnificent ship, seated on her royal throne. Antony, too, fell in love with the proud queen.

In 35 bc, Antony married Cleopatra and they lived in Egypt. The next year, they announced that they were the rulers of the eastern part of the Roman Empire. This included Egypt and most of the Middle East.

The Roman rulers were angered by this. Roman general Octavian declared war on Antony and Cleopatra. In 31 bc, Octavian won the war and took over Egypt. Both Antony and Cleopatra killed themselves.

Albert Einstein was born in Ulm, Germany, on March 14, 1879. He grew up in Germany, Italy, and Switzerland. Einstein taught himself geometry when he was 12 years old. School bored him because it required endless memorizing and reciting. He often skipped classes to study on his own or to play his violin. Yet he graduated from college in 1900 and earned a Ph.D. degree in 1905. From 1902 to 1907, Einstein worked as a clerk in the patent office in Zürich, Switzerland. His job left him plenty of time to think.

Einstein thought about the rules that govern the way the world works. For example, he explained why small particles in liquids wiggle around, a movement called Brownian motion. He said that the particles were being bumped into by tiny bits of matter called atoms that are too small to see.

He also thought about light and electricity. Einstein knew that light shining on metal sometimes causes electricity to flow. He explained this result, called the photoelectric effect, by saying that light is made of tiny bundles of energy called photons. Photons hitting the metal knock particles called electrons away. Since electricity is simply moving electrons, he had solved the mystery of the photoelectric effect. In 1921, Einstein won the most famous prize in science, the Nobel Prize, for this work.

Another thing Einstein thought about was time. He said that time does not always flow at the same rate. He proposed that motion affects time. He called this idea the special theory of relativity.

Einstein then came up with his general theory of relativity. This theory has a new explanation for gravity. Einstein said that gravity comes from curves or dents in the fabric of space. Objects make dents in space the way a bowling ball makes a dent in a mattress. The Moon falls into the dent made by Earth and rolls around the Earth. Scientists later proved that the dent a star makes in space-time bends light as the light passes by.

Einstein changed physics by showing that new ideas could come just from thinking. Before Einstein, most new ideas in physics had come from experiments in the laboratory.

Einstein also said that matter and energy are the same thing. He expressed this relation in a famous equation: E=mc². This equation says that energy (E) equals mass (m) times the speed of light squared (c²). Energy can therefore be changed into matter, and matter into energy. The ability to turn matter into energy led to the development of the atomic bomb and nuclear power.