Wonders of the Universe. Andrew Cohen

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СКАЧАТЬ forces in the Universe, but because it has an infinite range and acts between everything that exists, its influence is all-pervasive. Our most precise theory of gravity, Einstein’s General Theory of Relativity, dates from 1915, which makes it the oldest of the modern theories of the forces. The theory of the electromagnetic force, Quantum Electrodynamics, dates from the 1950s, while the theory of the Strong Nuclear Force from the 1960s and 70s. Our description of last of the four, the Weak Nuclear Force, resides in the Standard Model of particle physics. This theory, a product of the 1970s, unifies the description of the Weak Nuclear Force with Quantum Electrodynamics, although there is a missing piece of the theory known as the Higgs Boson that is currently being searched for at the Large Hadron Collider at CERN in Geneva. Until the Higgs Boson, or whatever does its job, is found, we cannot claim to have a working description of the Weak Nuclear Force and its relationship with electromagnetism.

      However despite the long pedigree and beautiful accuracy and elegance of Einstein’s theory of gravity, it is known to be incomplete. Our description of the Universe breaks down in the heart of its most evocatively named wonders. Black holes are known to exist at the centre of galaxies such as the Milky Way, and are dotted throughout the cosmos; the carcasses of the most massive stars in the Universe. We see them by their influence on passing stars and by detecting the intense radiation emitted by gas and dust that has the misfortune to venture too close to their event horizons. We have even seen their formation in the most violent cosmic events – supernova explosions. These events mark the destruction of stars that once burned brightly for millennia, completed in a matter of minutes.

      The final chapter, ‘Destiny’, delves into the distant past and the far future; following the inevitable ticking of the universal clock. It is also the chapter that most directly touches on the great contribution of engineering to our story. The science of thermodynamics, which has become our guide to the ultimate fate of the Universe, arose from considerations of the efficiency of steam engines in the nineteenth century and not a desire to peer out towards a possibly infinite future. In ‘Destiny’ we describe thermodynamics in detail, and show how this quintessentially nineteenth-century science allows us to speculate with some grounding in reality about events that will happen 10,000,000,000,000,000,000,000,000,000,000,000,

      000,000,000,000,000,000,000,000,000,000,000,000,000,000,

      000,000,000,000,000,000,000,000 years from now. Not bad for the pioneers of the age of steam.

      So as we look to the future and survey the wonders of our universe, we discover that Einstein’s theory of gravity, our best description of the fabric of the Universe, predicts its demise inside black holes. The collapsing remnants of the most luminous stars represent the edge of our understanding of the laws of physics and therefore the edge of our understanding of the wonders of the Universe. This is exactly where every scientist wants to be. Science is a word that has many meanings; one might say science is the sum total of our knowledge of the Universe, the great library of the known, but the practice of science happens at the border between the known and the unknown. Standing on the shoulders of giants, we peer into the darkness with eyes opened not in fear but in wonder. The fervent hope of every scientist is that they glimpse something that not only requires a new scientific theory, but that requires the old theory to be replaced. Our great library is constantly being rewritten; there are no sacred tomes; there are no untouchable truths; there is no certainty; there is simply the best description we have of the Universe, based purely on our observations of its wonders.

      The scientific project is ultimately modest: it doesn’t seek universal truths and it doesn’t seek absolutes, it simply seeks to understand – and therein lies its power and value. Science has given us the modern world, of that there can be no doubt. It has improved our lives beyond measure; increased life expectancy, decreased child mortality, eradicated many diseases and rendered many more impotent. It has given many of us the gift of time, freed us from the drudgery of mere survival and allowed us to open our minds and explore. Science is therefore a virtuous circle; its discoveries creating more time and wealth that we can, if we are wise, invest in further voyages of exploration and discovery. But for all its undoubted usefulness, I maintain that science is fuelled not by utilitarian desire but by curiosity. The exploration of the Universe and its wonders is as important as the search for new medical treatments, new energy sources or new technologies, because ultimately all these valuable advances rest on an understanding of the basic laws that govern everything in nature, from atoms to black holes and everything in between. This is why curiosity-driven science is the most valuable of pursuits, and this is why we must continue our journey into the darkness

      Armed with a greater knowledge and understanding of our universe, and also with new technology and modern approaches to science, we can discover wonders of the Universe that would have remained hidden to us centuries ago. Galaxies such as the spiral-shaped Dwingeloo 1 have recently been found hidden behind the Milky Way. This discovery supports what we already know: that there are many more wonders out there in the Universe that we have yet to discover.

      CHAPTER 1

      MESSENGERS

THE STORY OF LIGHT

      Throughout recorded history humans have looked up to the sky and searched for meaning in the heavens. The science of astronomy may now conjure thoughts of telescopes and planetary missions, but every modern moment of discovery has a heritage that stretches back thousands of years to the simplest of questions: what is out there? Light is the only connection we have with the Universe beyond our solar system, and the only connection our ancestors had with anything beyond Earth. Follow the light and we can journey from the confines of our planet to other worlds that orbit the Sun without ever dreaming of spacecraft. To look up is to look back in time, because the ancient beams of light are messengers from the Universe’s distant past. Now, in the twentieth century, we have learnt to read the story contained in this ancient light, and it tells of the origin of the Universe.

      The spectacular remains and towering pillars of Karnak Temple are a testament to the Egyptian belief in the power and importance of the Amun-Re, the Sun God, in their daily life, and of the Sun itself.

      Karnak Temple, home of Amun-Re, universal god, stands facing the Valley of the Kings across the Nile in the city of Luxor. In ancient times Luxor was known as Thebes and was the capital of Egypt during the opulent and powerful New Kingdom. At 3,500 years old, Karnak Temple is a wonder of engineering, with thousands of perfectly proportioned hieroglyphs, and an architectural masterpiece of ancient Egypt’s golden age; it is a place of profound power and beauty. Ten European cathedrals would fit within its walls; the Hypostyle Hall alone, an overwhelming valley of towering pillars that once held aloft a giant roof, could comfortably contain Notre Dame Cathedral.

      Religious and ceremonial architecture has had many functions throughout human history. There is undoubtedly a political aspect – these monumental edifices serve to cement the power of those who control them – but to think of the great achievements of human civilisation in these terms alone would be to miss an important point. Karnak Temple is a reaction to something far more magnificent and ancient. The scale of the architecture forcibly wrenches the mind away from human concerns and towards a place beyond the merely terrestrial. Places like this can only be built by people who have an appropriate reverence for the Universe. Karnak is both a chronicle in stone and a bridge to the answer to the eternal question: what is out there? It is an observatory, a library and an expression carved out of the desert of cosmological curiosity and the desire to explore.

      Egyptian religious СКАЧАТЬ