Update

history.md

@@ -6,6 +6,8 @@ This is a brief summary of history of [technology](technology.md) and [computers
 
 { A curious pattern of history is that the civilization -- or maybe rather the dominating superpowers -- are moving to the west, kind of like: middle East -> Greece -> Rome -> Holy Roman Empire -> England/France/Spain -> America. ~drummyfish }
 
+The [Universe](universe.md) began in singularity and started to exist with [Big Bang](big_bang.md) almost 14 billion years ago. It went through several epochs during which it changed greatly: first there was the epoch of rapid inflation, up to about 10^-32 seconds, during which it expanded extremely rapidly. After this the fundamental forces (strong, weak, electromagnetic and gravitational) started to become separate, the universe was cooling down, it became transparent and then, after 200 million years, first stars started to form. After another 200 million years first galaxies started to form, including our own Milky Way galaxy. Our [Earth](earth.md) formed some 4.5 billion years ago, along with the Moon. It seems [life](life.md) appeared about 3.8 billions years ago; about 600 million years ago multicellular life formed and 66 million years ago the dinosaurs went extinct, giving opportunity to mammals and eventually to us, humans.
+
 The earliest known appearance of technology related to humans may likely be the use of **[stone](rock.md) tools** by hominids in Africa some two and a half million years ago -- this is even before the appearance of modern humans, homo sapiens, that emerged roughly 600000 years ago. Learning to start and control **[fire](fire.md)** was another key invention of the earliest men; this probably happened hundreds of thousands to millions years ago, even before modern humans. Around 8000 BC the **[Agricultural Revolution](agricultural_revolution.md)** happened: this was quite a disaster -- as humans domesticated animals and plants, they had to abandon the comfortable life of hunters and gatherers and started to suffer the life of a farmer, full of extremely hard [work](work.md) in the fields (this can be seen e.g. from their bones). This led to the establishment of first cities that would later become city states (as the name says -- something between a city and a state, i.e. greatly independent cities with their own laws etc.). Some of the first such cities were Ur and Uruk in Mesopotamia, since around 5000 BC. Primitive **writing** can be traced to about 7000 BC to China. **[Wheel](wheel.md)** was another crucial piece of technology humans invented, it is not known precisely when or where it appeared, but it might have been some time after 5000 BC -- in Ancient Egypt **The Great Pyramid** was built around 2570 BC still without the knowledge of wheel. Around 4000 BC **history starts with first written records**. Humans learned to smelt and use [metals](metal.md) approximately 3300 BC (**Bronze Age**) and 1200 BC (**Iron Age**). **[Abacus](abacus.md)**, one of the simplest [digital](digital.md) devices aiding with computation, was invented roughly around 2500 BC. However people used primitive computation helping tools, such as bone ribs, probably almost from the time they started trading. Babylonians in around 2000 BC were already able to solve some forms of **[quadratic equations](quadratic_equation.md)**.
 
 In Greek many city states, such as Athens, Delphi and Sparta formed -- Ancient Greek culture would be seen as the golden age of civilization that would lay foundations to everything we now take for granted; Greeks to some extent advanced technology (e.g. architecture) but especially cultivated [art](art.md), philosophy and [politics](politics.md) -- Athens are credited for inventing [democracy](democracy.md) (though an "early" version, they still had slaves and many classes of citizens without voting power). In 8th century BC Homer created the epic poems Iliad and Odyssey. In 6th century BC Pythagoras describes the [Pythagorean theorem](pythagorean_theorem.md). After 600 BC the Greek [philosophy](philosophy.md) starts to develop which would lead to strengthening of rational, [scientific](science.md) thinking and advancement of [logic](logic.md) and [mathematics](math.md). Some of the most famous Greek philosophers were [Socrates](socrates.md), [Plato](plato.md), [Aristotle](aristotle.md) and [Diogenes](diogenes.md). Around 400 BC **[camera obscura](camera_obscura.md)** was already described in a written text from China where **[gears](gear.md)** also seem to have been invented soon after. Around 300 BC Euklid wrote his famous *Elements*, a mathematical work that proves theorems from basic [axioms](axiom.md). Ancient Greeks could communicate over great distances using **Phryctoria**, chains of fire towers placed on mountains that forwarded messages to one another using light. 234 BC Archimedes described the famous [Archimedes screw](archimedes_screw.md) and created an **[algorithm](algorithm.md) for computing the number [pi](pi.md)**. In 2nd century BC the **Antikythera mechanism, the first known [analog](analog.md) [computer](computer.md)** is made to predict movement of heavenly bodies. Romans are known to have been great builders, they built many roads and such structures as the Pantheon (126 AD) and aqueducts with the use of their own type of **concrete** and advanced understanding of physics.