What is Cosmology?

What is Cosmology?

Cosmology is a branch of astronomy related to the study of the origin and development of the universe, from the Big Bang to the present and the future. This is the scientific study of the origin, development and final fate of the universe. Physical cosmology is the scientific study of the laws of science, along with the origin of the universe, its massive structures and mobility, and its ultimate destiny, which govern these areas.

The term cosmology was first used in English in Glossographia of Thomas Blunt in 1656 and in 1731 in Latin by German philosopher Christian Wolff in Cosmologia Generalis.

Religious or mythological cosmology is a body of beliefs based on mythology, religious and esoteric literature and the traditions of creation myths and traditions.

Physical cosmology is studied by scientists, such as astronomers and physicists, as well as philosophers, such as metaphysics, philosophers of physics, and philosophers of space and time. Due to this shared circle with philosophy, the principles in physical cosmology can include both scientific and non-scientific proposals and may depend on the beliefs which can not be tested. Cosmology differs from astronomy in the sense that the former is related to the universe, while later related to individual celestial objects. In the Big Bang theory, modern material universe is dominated by science, which attempts to bring observation of astronomy and particle physics together; More specifically, a standard parameter of Big Bang with the dark bang and dark energy, known as Lambda-CDM model.

Theoretical astrologer David N. Spergel has described cosmology as a "historical science" because "when we look into space, we look back in time" due to the finite nature of light's motion.

History of cosmology & astronomy

The understanding of the humanity of the universe has evolved over time. In the early history of astronomy, the earth was considered as the center of all things, with orbiting the planets and stars. In the 16th century, Polish scientist Nicholas Copernicus suggested that the Earth and the other planets of the Solar System actually orbited the Sun, thereby deepening the understanding of the universe. In the second half of the 17th century, Isaac Newton calculated that the forces between the planets - especially the gravitational force - interact with each other.

On the morning of the 20th century brought more insight into understanding the vast universe. Albert Einstein proposed the integration of space and time in his general theory of relativity. At the beginning of the 1900s, the scientists were debating whether Milky had covered the entire universe within its time, or was it just one of the many collections of stars. Edwin Hubble calculated the distance of a vague obscure object in the sky and determined that it is located outside the Milky Way, which proves our galaxy a small drop in the vast universe. Using general relativity to lay out the framework, Hubble measured the other galaxies and determined that they were running away from us, from which they were concluded that the universe was not stable but was expanding.

In recent decades, cosmologist Stephen Hawking determined that the universe itself is not infinite, but there is a certain shape. However, it lacks a certain limit. It is like the earth; Although the planet is finite, the person traveling around it will never get "end", but it will continually surround the globe. Hawking also proposed that the universe would not continue forever, but eventually it would end.

mission of Cosmology

Launched in November 1989, NASA's Cosmic Background Explorer (COBE) took accurate measurements of radiation throughout the sky. Mission operated until 1993.

Although NASA's Hubble Space Telescope is perhaps known for its astounding images, a primary mission was cosmological. By measuring the distance more accurately for the Satisfied variables, with a well-defined ratio between their glow and their vibrations, Hubble helped to refine the measurements about the expansion of the universe. Since the launch, astronomers have continued to use Coburgical measurements and Hubble to refine the existing ones.

In a statement, cosmologist Adam Rieses of the Space Telescope Science Institute said, "Thank you for the Hubble," if you put it in a box, in which the dark energy can be separated from the cosmic Continental, that box will now be three times smaller. "This is progress, but we still have to go a long way to reduce the nature of dark energy."

NASA's Wilkinson Microwave Anisotropy Detection (WMAP) was a space shuttle that operated from 2001 to 2010. WMAP indicated a small fluctuation in the Cosmic Microwave Background (CMB), which was the ancient light from the early universe, and determined that simple atoms make up only 4.6%. The universe, while dark matter makes 24 percent.

Cosmologist Charles Saif said in the journal Science, "The existence of doubt on the existence of dark energy and the composition of the universe was dissolved when WMAP satellites took the most detailed picture of the Cosmic Microwave Background."

The Planck Space Mission of the European Space Agency ran from 2009 to 2013 and continued to study Cosmic microwave background.

ESA is currently developing Euclid mission, which must fly by the end of the decade. Euclid will study dark matter and dark energy with greater accuracy by detecting its distribution and development through the universe.

ESA's David Parker said in a statement, "One of the billion pounds of physics questions at the center of the mission."

Cosmology related questions 

What came before the Big Bang?

Due to the enclosed and finite nature of the universe, we can not see the "outside" of our own universe. Space and time began with the Big Bang. While there are many speculations about the existence of other universes, there is no practical way of looking at them, and as if for them (or against!) There will be no evidence.

Where did the big bang happen?

The Big Bang did not happen at one point, but it was the presence of space and time together in the whole universe.

If other galaxies seem to run away from us, does not it keep us in the center of the universe?

No, because if we were going to travel to a distant galaxy, it would appear that all the galaxies surrounding were running equally. Think of the universe as a huge balloon. If you mark several points on the balloon, blow it up, you will notice that every point is going away from all others, although no one is at the center. The expansion of the universe works very much the same way.

How old is the universe?

According to figures released by the Planck team in 2013, the universe is 13.8 billion years old, give a hundred million years or more. Planck determined the age after the low-temperature fluctuations in CMB.

"The American scientist for Planck, Charles Lawrence said in a statement," Patterns on the vast patch of the sky tell us what was happening at the highest scales in moments after the birth of our universe.

Will the universe end? if so, how?

Whether or not the end of the universe will end, it depends on its density - it may be that the matter within it spreads so much. Scientists have calculated "significant density" for the universe. If its actual density is more than its calculations, eventually the expansion of the universe will slow down and then, eventually, it will be reversed until it collapses. However, if the density is less than significant density, then the universe will continue to expand forever. [More: How the universe will end]

Which came first, chicken ... er, galaxy or stars?

The Big Bang universe was composed primarily of hydrogen, in which a little helium was thrown for good measure. Due to gravity, hydrogen collapses inwardly, forming structures. However, astronomers are uncertain whether the first large drops formed different stars that would later fall together through gravity, or came together in large-scale galaxies-shaped clusters, which later became known as stars Were formed.