BBC Nature - History of life on Earth THE BIG BANG Chris LaRocco and Blair Rothstein present: The Hubble Telescope's deepest view of the universe teaches us about the beginning We certainly know that our universe exists, however, this knowledge alone has not satisfied mankind's quest for further understanding. Our curiosity has led us to question our place in this universe and furthermore, the place of the universe itself. We have, however, come a long way from the mystical beginnings of the study of cosmology and the origins of the universe. Although in this short chapter it will be impossible to tackle all of the questions concerning the creation of everything we know as reality, an attempt will be made to address certain fundamental questions of our being. One of the most persistently asked questions has been: How was the universe created? About 15 billion years ago a tremendous explosion started the expansion of the universe. The origin of the Big Bang theory can be credited to Edwin Hubble. or Literature Kaufmann, William J., III.
The Universe This picture shows the overall structure of our universe. This is just a small piece, but it is enough to see that matter is organized in strands, or strings. Lets start from the beginning. The Earth revolves around the Sun. The Sun in turn revolves or circles the center of the galaxy. Our galaxy is part of a group of galaxies called the Local Group. Now here is where it gets fun. Millions of galaxy clusters around the universe are strung together like a spiderweb. If you could look at the entire universe at once it would look like a giant spiderweb, made up of billions of galaxies, and trillions and trillions of stars.
What Happened Before the Beginning? Every cosmologist and astronomer agrees: our Universe is 13.7 billion years old. Using cutting-edge technology, scientists are now able to take a snapshot of the Universe a mere heartbeat after its birth. Armed with hypersensitive satellites, astronomers look back in time to the very moment of creation, when all the matter in the Universe exploded into existence. It is here that we uncover an unsolved mystery as old as time itself - if the Universe was born, where did it come from? The big bang theory holds that the entire universe was once packed tightly into an unimaginably dense and tiny space, known as a "singularity." But what brought about that big bang? Successfully answering the question of what existed before the big bang would require bridging the gap between the so-far mutually incompatible worlds of relativism and quantum mechanics. This is the fourth episode. Watch the full documentary now
Fossil of ancient multicellular life sets evolutionary timeline back 60 million years -- ScienceDaily A Virginia Tech geobiologist with collaborators from the Chinese Academy of Sciences have found evidence in the fossil record that complex multicellularity appeared in living things about 600 million years ago -- nearly 60 million years before skeletal animals appeared during a huge growth spurt of new life on Earth known as the Cambrian Explosion. The discovery published online Wednesday in the journal Nature contradicts several longstanding interpretations of multicellular fossils from at least 600 million years ago. "This opens up a new door for us to shine some light on the timing and evolutionary steps that were taken by multicellular organisms that would eventually go on to dominate the Earth in a very visible way," said Shuhai Xiao, a professor of geobiology in the Virginia Tech College of Science. The discovery sheds light on how and when solo cells began to cooperate with other cells to make a single, cohesive life form.
Waves from the Big Bang News News Features Nature Video Nature Podcast News from the Archive News and Views Books and Arts Fiction Top Content - Article Page Research integrity Don't let transparency damage science How can the research community protect its members from harassment, while encouraging the openness that has become essential to science? Nature Podcast This week... The computer that can play Go, a general 'ageing' factor, and the stolen library of John Dee. History of Earth Artistic concept of the primordial Earth when it was much hotter and hostile to life The history of Earth concerns the development of the planet Earth from its formation to the present day. Nearly all branches of natural science have contributed to the understanding of the main events of the Earth's past. The age of Earth is approximately one-third of the age of the universe. An immense amount of biological and geological change has occurred in that time span. The first life forms appeared between 3.8 and 3.5 billion years ago. Geological change has been constantly occurring on Earth since the time of its formation and biological change since the first appearance of life. Earth's history with lengths of the eons to scale Geologic time scale The history of the Earth is organized chronologically in a table known as the geologic time scale, which is split into intervals based on stratigraphic analysis. A full-time scale can be found at the main article. Millions of Years
Did a hyper-black hole spawn the Universe? The event horizon of a black hole — the point of no return for anything that falls in — is a spherical surface. In a higher-dimensional universe, a black hole could have a three-dimensional event horizon, which could spawn a whole new universe as it forms. It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole — a scenario that would help to explain why the cosmos seems to be so uniform in all directions. The standard Big Bang model tells us that the Universe exploded out of an infinitely dense point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment. “For all physicists know, dragons could have come flying out of the singularity,” says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada. On the brane Model discrepancy
Timeline: The evolution of life By Michael Marshall There are all sorts of ways to reconstruct the history of life on Earth. Pinning down when specific events occurred is often tricky, though. For this, biologists depend mainly on dating the rocks in which fossils are found, and by looking at the “molecular clocks” in the DNA of living organisms. There are problems with each of these methods. Modern genetics allows scientists to measure how different species are from each other at a molecular level, and thus to estimate how much time has passed since a single lineage split into different species. These difficulties mean that the dates in the timeline should be taken as approximate. 3.8 billion years ago? This is our current “best guess” for the beginning of life on Earth. At some point far back in time, a common ancestor gave rise to two main groups of life: bacteria and archaea. How this happened, when, and in what order the different groups split, is still uncertain. 3.5 billion years ago 3.46 billion years ago
What Came Before the Big Bang? It is cosmology’s most fundamental question: How did the universe begin? The question presupposes that the universe had an actual starting point, but one might just as well assume the universe always was and always will be. In that case, there would be no beginning whatsoever — just an ever-evolving story of which we’re catching a mere glimpse. “We have very good evidence that there was a Big Bang, so the universe as we know it almost certainly started some 14 billion years ago. But was that the absolute beginning, or was there something before it?” But now Vilenkin says he has convincing evidence in hand: The universe had a distinct beginning — though he can’t pinpoint the time. Throughout his career, including the 20-plus years he has directed the Tufts Institute of Cosmology, Vilenkin has issued a series of wild, dazzling ideas, though from the outside he looks neither wild nor dazzling. Yet this brilliant career might never have happened. Back to the Big Bang That would soon change.
How Was The Earth Created? Hello Earth - Origins of Our Planet Where did the Earth come from? This is an important question. A question that helps us understand our own origin as a race of sentient, thinking beings. Did the Earth always exist? These are difficult questions to answer. Big Bang According to the Big Bang model, the universe expanded from an extremely dense and hot state and continues to expand today. The graphic scheme above is an artist's concept illustrating the expansion of a portion of a flat universe. The Big Bang is the scientific theory that is most consistent with observations of the past and present states of the universe, and it is widely accepted within the scientific community. It offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background, large scale structure, and the Hubble diagram. The core ideas of the Big Bang—the expansion, the early hot state, the formation of light elements, and the formation of galaxies—are derived from these and other observations. As the distance between galaxies increases today, in the past galaxies were closer together. Overview Timeline of the Big Bang The earliest phases of the Big Bang are subject to much speculation.