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The History of the Universe in 100 words or less
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- Bu səhifədəki naviqasiya:
- Long Standing Questions Of Physics
- Mapping the dark universe
- Physics of Work Psychology
- A letter to Charles Darwin from Jerry Coyne (a professor in the Department of Ecology and Evolution at the University of Chicago and author of Why Evolution is True)
- Relative Strength of the Four Forces
The History of the Universe in 100 words or less Big Bang Explosion in which our universe was born from an infinitesimally small and, therefore, infinitely dense state of enormous density and pressure – Inflation in which the Grand Unified Force was separated into the Four Forces of Nature as We Now Know Them, and the Universe started to Expand to Many Times Its Original Size in a Very Short Period of Time – Rapid exponential expansion in which the universe cooled, this expansion was said to be inflationary — the size of the universe was much greater even than that — a million million million million million times in only a tiny fraction of a second -- PARTICLE-ANTIPARTICLE ANNIHILATION in which All the Antiparticles in the Universe Annihilated Almost All the Particles, Creating a Universe Made Up of Matter and Photons and no antimatter -- DEUTERIUM AND HELIUM PRODUCTION in which Many of the Protons and Neutrons in the Early Universe Combined to Form Heavy Hydrogen and Helium -- RECOMBINATION in which Electrons Combined with Hydrogen and Helium Nuclei, Producing Neutral Atoms -- GALAXY FORMATION in which the Milky Way Galaxy was Formed -- TURBULENT FRAGMENTATION in which a Giant Cloud of Gas Fragments broke into Smaller Clouds, which later Became Protostars -- MASSIVE STAR FORMATION in which a Massive Star was Formed -- STELLAR EVOLUTION in which Stars Evolved and Eventually Died-- IRON PRODUCTION in which Iron was Produced in the Core of a Massive Star, Resulting in a Disaster called SUPERNOVA EXPLOSION in Which a Massive Star Ended Its Life by Exploding -- outshining all the other stars in the galaxy and spraying heavier elements into the space which then flung back into the gas in the galaxy – STAR FORMATION in which the Sun was Formed-- PLANETARY DIFFERENTIATION in which the Planet Earth was Formed and made up of rocky silicates and a metal mixture of iron and nickel in a ratio of about nine to one -- VOLATILE GAS EXPULSION in which the Atmosphere of the Earth was Produced and the less massive atoms or molecules moved more quickly at a given temperature and escaped into space and it was more difficult to hold them on to as part of the atmosphere -- MOLECULAR REPRODUCTION in which Life on Earth was created -- PROTEIN CONSTRUCTION in which Proteins were built from Amino Acids like lysine, aspartic acid etc. -- FERMENTATION in which Bacteria Obtained Energy from Their Surroundings -- CELL DIFFERENTIATION in which Eukaryotic Life had a beginning -- RESPIRATION in which Eukaryotes Evolved to Survive in an Atmosphere with Increasing Amounts of Oxygen -- MULTICELLULAR ORGANISMS CREATION In Which Organisms Composed of Multiple Cells emerged -- SEXUAL REPRODUCTION in Which a New Form of Reproduction Occurred and with the invention of sex, two organisms exchanged whole paragraphs, pages and books of their DNA helix, producing new varieties for the sieve of natural selection. And the natural selection was a choice of stable forms and a rejection of unstable ones. And the variation within a species occurred randomly, and that the survival or extinction of each organism depended upon its ability to adapt to the environment. And organisms that found sex uninteresting quickly became extinct -- EVOLUTIONARY DIVERSIFICATION in which the Diversity of Life Forms on Earth Increased Greatly in a Relatively Short Time -- TRILOBITE DOMINATION In Which Trilobites (an extremely successful subphylum of the arthropods that were at the top of the food chain in Earth's marine ecosystems for about 250 million years) Ruled the Earth -- LAND EXPLORATION In Which Animals First Venture was Onto Land – COMET COLLISION in which a Comet smashed the Earth -- DINOSAUR EXTINCTION In Which the Dinosaurs Died -- MAMMAL EXPANSION in which Many Species of Mammals was Developed -- HOMO SAPIENS MANIFESTATION In Which our caveman ancestors Appeared – LANGUAGE ACQUISITION in which something called curiosity ensued which triggered the breath of perception and our caveman ancestors became conscious of their existence and they learned to talk and they Developed Spoken Language -- GLACIATION in which a Thousand-Year Ice Age Began --- INNOVATION in which Advanced Tools were Widely made and Used -- RELIGION In Which a Diversity of Beliefs emerged --- ANIMAL DOMESTICATION in which Humans Domesticated Animals -- FOOD SURPLUS PRODUCTION In Which Humans Developed and promoted Agriculture -- INSCRIPTION In Which Writing was Invented and it allowed the communication of ideas -- WARRING NATIONS In Which Nation Battled Nation for Resources --- EMPIRE CREATION AND DESTRUCTION In Which the First Empire in Human History Came and went --- CIVILIZATION In Which Many and Sundry Events Occurred -- CONSTITUTION In Which a Constitution was Written -- INDUSTRIALIZATION in Which Automated Manufacturing and Agriculture Revolutionized the World --- WORLD CONFLAGRATIONS In Which Most of the World was at War --- FISSION EXPLOSIONS In Which Humans Developed Nuclear Weapons -- COMPUTERIZATION In Which Computers were Developed --- SPACE EXPLORATION In Which Humans Began to Explore Outer Space --- POPULATION EXPLOSION In Which the Human Population of the Earth Increased at a Very Rapid Pace --SUPERPOWER CONFRONTATION In Which Two Powerful Nations Risked it All -- INTERNET EXPANSION In Which a Network of Computers Developed -- RESIGNATION In Which One Human Quitted His Job --- REUNIFICATION In Which a Wall went Up and Then Came Down --- WORLD WIDE WEB CREATION In Which a New Medium was Created --- COMPOSITION In Which a Book was Written --- EXTRAPOLATION In Which Future Events were Discussed. Long Standing Questions Of Physics Are there undiscovered principles of nature: new symmetries, new physical laws? How can we solve the mystery of dark energy? Are dark energy and the Higgs field related? What are neutrinos telling us? Is dark matter is made up of weakly interacting massive particles (something like heavy versions of the neutrinos)? What is dark matter? How can we make it in the laboratory? Why are there so many kinds of particles? Why the Higgs exists and who its cosmological cousins are? Which particles are travelers in extra dimensions, and what are their locations within them? Is out Universe part of a Multiverse? How did the universe come to be? What happened to the antimatter? What do we learn about the early Universe from experiments at the LHC? Can precise measures of the distribution of galaxies and DM unveil the nature of DM/DE? Why there is missing energy from a weakly interacting heavy particle? Is the direct discovery of the effects of extra dimensions or a new source of matter-antimatter asymmetry possible? An all-embracing theory of physics that unifies quantum mechanics (which applies to the very small: atoms, subatomic particles and the forces between them) and general relativity (which applies to the very large: stars, galaxies and gravity, the driving force of the cosmos) would solve the problem of describing everything in the universe from the big bang to subatomic particles? Our leading candidate for a theory of everything is known as M-theory. It grew from a merger of the two seemingly different approaches: 11-dimensional supergravity and 10-dimensional superstring theory. Could this be the final theory of everything? What do observations of galaxies at early times tell us about how galaxies were made?
PROFILING THE INVISIBLE Is physics about to SNAP? Or does it explain everything about the universe? To answer these most challenging questions about the nature of the universe, all the approaches must converge. Results from accelerator experiments at LHC must agree with most powerful and insightful astrophysical observations and results from sophisticated data. However, the experiments necessary to go beyond the existing knowledge of standard physics are rapidly becoming prohibitively expensive and time consuming and the macroscopic experiments are difficult to perform in the laboratory as subatomic reactions at the incredible energy scale of 109 GeV -- which is far beyond the range of our largest particle accelerators. Physics of Work Psychology If one work with a certain potential called work potential, then one feel so intensified on the work that one soon loses track of time passing. Working with potential less than work potential does not lead us in prolonging action. This is because the psychological barriers hold us from doing so. But, what is considered a psychological barrier? Well, it might be A lack of self-confidence. A threat of failure. A threat of being stepped out. A threat of rejection. Work potential = negative potential + driving potential. Negative potential = potential of psychological barriers i.e., potential of negative psychology that hold us from action. Driving potential = potential of positive psychology that drives us at work for a prolonged time. If driving potential = 0 (work potential = negative potential), we can overcome the psychological barriers, but we can’t stick on to work for a prolonged time. If work potential < Negative potential, psychological barriers hold us from action. The Potential is bizarrely personal; each of us possesses potential very much less than the work potential. The excess potential we should own so that our potential surmounts the work potential is known as the activation potential. Activation potential = work potential – normal potential If we yearn to acquire activation potential one need to adapt the principle of psychological quickness. But, what is considered a psychological quickness? Well, psychological quickness is simply the psychological eagerness to do work. As psychological quickness increases, positive psychological energy increases (i.e., negative psychological energy is converted to positive psychological energy—however, total psychological energy (positive plus negative) remains constant). As positive psychological energy increases, psychological barriers become less immense to hold us from prolonging action. When psychological quickness reaches a state of maximum – total psychological energy will no longer hold the negative psychological energy as its constituent part (i.e., negative psychological energy = 0 and total psychological energy will be = positive psychological energy) and since negative psychological energy = 0, negative potential decreases to minimum and approaches zero i.e., work potential will be = driving potential i.e., we stick on to work for a prolonged time. I cannot bear the thought of the Slave-holders being triumphant … : Darwin to Asa Gray, in Boston, Mass., 1862. Did you know that A German astronomer named Friedrich Wilhelm Bessel (1784-1846) was one of those who tried to measure the distance of stars and was in fact the first to succeed. A letter to Charles Darwin from Jerry Coyne (a professor in the Department of Ecology and Evolution at the University of Chicago and author of Why Evolution is True) My Dear Mr. Darwin, Happy 200th birthday! I hope you are as well as can expected for someone who has been dead for nearly 130 years. I suppose that your final book, the one about earthworms, has a special significance for you these days. Are the worms of Westminster Abbey superior to the ones you studied so carefully in the grounds of your home at Downe in Kent? They’ve certainly mulched some distinguished people over the years! But enough of the personal questions: let me introduce myself. I am one of thousands – maybe tens of thousands – of professional biologists who work full time on your scientific legacy. You’ll be happy to know that Britain remains a powerhouse in what we nowadays call evolutionary biology, and your ideas now have wide currency across the entire planet. I work in Chicago, in the United States of America. But even the French have finally reluctantly relinquished their embrace of Jean-Baptiste Lamarck, whose misguided evolutionary ideas you did so much to discredit. Your Origin of Species turns 150 this year. I just re-read it in your honour and must say that, though you did not always have the snappiest turn of phrase, it really is a wonderfully comprehensive and insightful work. It is remarkable, considering what you did not know when you wrote it, how robust the book has proved over the years. The findings of modern biology, many of them inconceivable to you as you beavered away in your Down House study, have provided ever more evidence in support of your ideas, and none that contradicts them. We have learned a huge amount in the past 150 years, but nearly all of it still fits comfortably into the framework you outlined in The Origin. Take DNA, for example. This is what we call the hereditary material that is passed down from generation to generation. You knew nothing about it – remember how you wished you understood more about how heredity works? Now we have full DNA sequences from dozens of species, each one a string of billions of the four DNA letters—A, T, G and C—each a different chemical compound. What do we find when we compare these sequences, say between a mouse and a human? We see the DNA equivalent of the anatomical similarities – as mammals – that you noted mice and humans share because they are descended from a common ancestor, an early mammal. Strings of As, Gs, Cs, and Ts tell precisely the same evolutionary story as traits like lactation and warm-bloodedness. It is absolutely marvelous that your 150 year old insight on common ancestry should be so relevant to the very latest discoveries of the new field we call molecular biology. In The Origin, you gave very little evidence for evolution from the fossil record, wringing your hands instead about the incompleteness of the geological record. But since then, the labors of fossil-hunters throughout the world have turned up plenty of evidence of evolutionary change, and many amazing “transitional” forms that connect major groups of animals, proving your idea of common ancestry. You predicted that these forms would exist; we have found them. These include fossils that show transitions between mammals and reptiles, fish and amphibians, and even dinosaurs with feathers—the ancestors of birds! Just in the past few years, paleontologists have unearthed an astonishing fossil, called Tiktaalik, that is intermediate between fish and amphibians. It has the flat head and neck of an amphibian, but a fishy tail and body, while its fins are sturdy, easily able, with slight modification, to give them a leg up when they left the water. The fossil record has given us a direct glimpse of an event of great moment in the history of the planet: the colonization of land by vertebrates. And we have evidence just as convincing for the recolonization of the sea by mammals: the group that gave rise to whales. In The Origin, you were correct in suggesting that whales arose from land animals, but you got it wrong on one point. You thought they may have come from carnivores like bears, but we now know this is not true. Instead, the ancestral whale came from a small hooved animal rather like a deer. And in the last thirty years we have discovered a whole series of intermediate fossils spanning the gap from those ancient deer to modern whales, showing them losing their hind legs, evolving flippers, and moving their breathing hole to the top of their head. Both Tiktaalik and these ancestral whales put paid to the objection, which you yourself encountered, that no transitional form between land and water could possibly have existed. Perhaps the most remarkable set of intermediate fossils, however, come from an evolutionary transition rather closer to home. In 1871, you more predicted that, since humans seem most related to African great apes, gorillas and chimpanzees, we would find human fossils on that continent. And now we have them—in profusion! It turns out that our lineage separated from that of chimpanzees, our closest living relatives, nearly 7 million years ago, and we have a superb series of fossils documenting our transition from early apelike creatures to more modern human forms. Our own species has become an exemplar of evolution. And we know even more: evidence from our hereditary DNA material has told us that all modern humans came from a relatively recent migration event—about 100,000 years ago—when our ancestors left Africa and spread throughout the world. The idea you were proudest of was natural selection. That too has had a good 150 years, holding up well as the main cause of evolution and the only known cause of adaptation. Perhaps the most dramatic modern example involves bacteria that are now known to cause disease, including the scarlet fever that was such a plague upon your family. Chemists have developed drugs to cure diseases like this, but now, as you might well predict, the microbes are becoming resistant to those drugs—precisely in accord with the principles of natural selection—for the most drug-resistant microbes are the ones that survive to breed. There are hundreds of other cases. One that will especially please you is the observation of natural selection in the Galápagos finches you collected in the Beagle voyage—now called “Darwin’s finches” in your honor. A few decades ago, zoologists observed a great drought on the islands that reduced the number of small seeds available for the birds to eat. And, just as predicted, natural selection caused the evolution of larger-beaked birds within only a few years. These examples would surely be a centerpiece of The Origin were you to rewrite it today. All told, the resilience of your ideas is remarkable. But that is not to say that you got everything right. On The Origin of Species was, admit it, a misnomer. You described correctly how a single species changes through time, but you came a cropper trying to explain how one species splits into two. Speciation is a significant problem, because it underpins the branching process that has yielded the tree of life – that extraordinary vision you bequeathed us of the natural world as one vast genealogy. Speciation is the key to understanding how, starting with the very first species on earth, evolution has resulted in the 50 million species that are thought to inhabit our planet today. You once called speciation the “mystery of mysteries,” but it’s a lot less mysterious these days. We recognize now that species are separated one from another by barriers to reproduction. That is, we recognize different species, like humans and chimpanzees, because they cannot successfully interbreed. To modern evolutionary biologists, studying “the origin of species” means studying how these barriers to reproduction arise. And now that we have a concrete phenomenon to investigate, we are making remarkable progress in understanding the genetic details of how one species splits into two. This is in fact the problem to which I’ve devoted my entire career I wish I could end this letter by telling you that your theory of evolution has achieved universal acceptance. As you well knew, evolution has proved a bitter pill for religious people to swallow. For example, a large proportion of the American public, despite access to education, clings to a belief in the literal truth of Genesis. You will find this hard to believe, but more Americans believe in the existence of heavenly angels than accept the fact of evolution. Unfortunately, I must often put aside my research to fight the attempts of these “creationists” to have their Biblical views taught in the public schools. Humans have evolved extraordinary intellectual abilities, but sadly these are not always given a free rein by their owners. But this probably won’t surprise you – remember the Bishop of Oxford and his attempt to put your friend Thomas H. Huxley in his place? You wrote in your introduction to The Origin of Species that “No one can feel more sensible than I do of the necessity of hereafter publishing in detail all the facts, with references, on which my conclusions have been grounded; and I hope in a future work to do this.” It seems that, distracted by other projects, you never got around to it, but my own effort along these lines is represented in a book (which I enclose) called Why Evolution is True. It goes further to describe the evidence supporting you than a letter this size ever could, but it’s just one book at just one moment in the history of biology. When I myself am as long gone as you are, somebody else will certainly need to write an update, for the facts supporting your theories continue to roll in, and I wager they will continue to do so. So, rest in peace, Mr. Darwin, and here’s hoping that the next hundred years will see a steady evolution of rationality in a troubled world. Your most humble servant, Jerry Coyne
Force: Nuclear Relative Strength: 103 Force: Electromagnetic Relative Strength: 1 Force: Weak Relative Strength: 10-11 Force: Gravitational Relative Strength: 10-39 Proton feel Nuclear force: Yes Electromagnetic force: Yes Weak force: No Gravitational force: Yes Neutron feel Nuclear force: Yes Electromagnetic force: No Weak force: No Gravitational force: Yes Electron feel Nuclear force: No Electromagnetic force: Yes Weak force: Yes Gravitational force: Yes The more massive a star, the more luminous it will be. This rule is called the mass-luminosity law. Did you know that: In 2012, in Large Hadron Collider physicists discovered GOD PARTICLE or Higgs Boson having mass 125GeV (which so far fits predictions of the Higgs previously made by theoretical physicists). This proved to be Nobel Prize discovery for Prof. Peter Higgs. In 2015, in upgrades set up experiments were conducted with double energy 13-14TeV. Scientists discovered or reported, a bizarre Boson which is 6 times heavier i.e. having mass 750 TeV. It was unexpected and upset the previous theories. When we place two long parallel uncharged plates close to each other, virtual particles outside the plates exerts more pressure than the virtual particles inside the plates, and hence the plates are attracted to each other, which we call the “Casimir effect.” “The effort to understand the universe is one of the very few things that lifts human life a little above the level of farce, and gives it some of the grace of tragedy.” : Steven Weinberg (winner of the Nobel Prize in Physics in 1979, and author of the book "The First Three Minutes"). References
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