How old is the Universe? For generations, people argued over whether the Universe had always existed, whether it had a beginning, or whether it was cyclical: with neither a beginning nor an end. But starting in the 20th and continuing into the 21st century, we not only drew a scientific conclusion to that question — the Universe (as we recognize it) began with a hot Big Bang — but we were able to pinpoint precisely when that beginning occurred. We now state, with confidence, that the Universe is 13.8 billion years old. But how confident can we really be in that answer?
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In the 1970s, physicists realised that there are very close ties between two of the four fundamental forces – the weak force and the electromagnetic force. The two forces can be described within the same theory, which forms the basis of the Standard Model. This “unification” implies that electricity, magnetism, light and some types of radioactivity are all manifestations of a single underlying force known as the electroweak force.
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Astronomers combine mathematical models with observations to develop workable theories of how the Universe came to be. The mathematical underpinnings of the Big Bang theory include Albert Einstein's general theory of relativity along with standard theories of fundamental particles. Today NASA spacecraft such as the Hubble Space Telescope and the Spitzer Space Telescope continue measuring the expansion of the Universe. One of the goals has long been to decide whether the Universe will expand forever, or whether it will someday stop, turn around, and collapse in a "Big Crunch?"
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A black hole is a region of spacetime where gravity is so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.
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Quantum computing is the use of quantum phenomena such as superposition and entanglement to perform computation. Computers that perform quantum computations are known as quantum computers.They are believed to be able to solve certain computational problems, such as integer factorization (which underlies RSA encryption), substantially faster than classical computers. The study of quantum computing is a subfield of quantum information science. It is likely to expand in the next few years as the field shifts toward real-world use in pharmaceutical, data security and other applications
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Richard Fehynman
Stephen
Wiesner