[PDF] ↠ Dark Matter and the Dinosaurs Author Lisa Randall – Shiningweb.info

Dark Matter and the Dinosaurs Randall is the first to warn her reader that her new hypothesis is speculative and in need of testing However, she is excited about the kinds of questions this new direction is taking her Randall has been investigating how dark matter might be involved in not only the creation of matter itself, but possibly in the evolution of humans as well The presence of dark matter is not at all speculative It has been detected using a variety of tools and methods What is speculative is the notion that some dark matter might interact with itself Just as ordinary matter comes in different varieties different sizes, charges, etc dark matter too might come in different varieties, some of which might not make a halo, but rather a dense disc that cuts through the the Milky Way and provides an extra gravitational force that might throw a comet off its trajectory and allow it to plunge toward and into earth, thus changing the temperature and atmosphere of Earth Randall has a mixed style of writing At times she makes analogies that are so fantastic, they seem among the best I have read At times though, her writing is dry For example, I found the chapter on Cuvier who I actually love and catastrophe to be so dry, I had trouble paying attention But, her chapters on the structure of the universe how matter was formed, how matter collapses into a disc, how clumping follows the rich get richer power laws,how heavy elements actually help in cooling so that large objects like our sun can form, etc were actually page turners for me I reread some of those sections than once because they were so exciting One of my favorite parts of the book was her discussion of Occam s Razor She prosed a table setting around core function It was brilliant Also wonderful, she treated her reader to a version of human s are not special that went way beyond most things associated with the Copernican revolution She suggested that matter, everything we have ever seen in the universe, is not special So great to be reminded of that I actually laughed audibly while reading that section I cannot wait to see what the telescope Gaia finds Of course I am hoping it will support Randall and Reece s hypothesis If it does not, I am still excited to continue hearing about the questions that continue to drive Randall s work. I quite enjoy reading cutting edge physics books, particularly about the latest premises of quantum theory and cosmology So I thought this was right up my alley Turns out it wasn t my alley, it was a dead end I did not enjoy Dark Matter and the Dinosaurs the Astounding Interconnectedness of the Universe.I m not a physicist but as long as you leave the maths out, I can follow most complex arguments I got lost in the first half of DMATDTAIOTU The first half of the book is primarily about why dark matter must theoretically speaking exist I found that Randall makes way too many assumptions here to really understand her argument She tosses off too many technical terms casually and proofs too convoluted for a layperson.At some point, Randall reveals that no one has yet observed dark matter nor do physicists KNOW WHAT IT IS Most think it LIKELY to exist based on various observations of the behavior of the universe related to gravity and the spread of matter in the universe Apparently, five sixths of the universe is invisible, you see The universe acts as if there is matter there, but it is utterly invisible to light What could this be Or, is it possible, scientists just don t truly understand gravity yet to explain this effect Here s an article that explains all this much better, clearly, and concisely than Lisa Randall does second half of the book is around understanding the frequencies and trajectories of asteroids, meteoroids and comets This eventually leads to the hypothesis, which is the central subject of the book That if dark matter actually exists, it may perhaps form a particular disk like shape in the galaxy which when our solar system passes through it could trigger comets to break away from the distant Oort cloud far outside our solar system and dive toward or away from the sun and one of them hit the earth and killed the dinosaurs and most of the other life on the planet This theory, by the way, is not only dependent upon the existence of dark matter and its hypothetical structure, but it s also dependent on another very hypothetical assumption, that of the periodicity of comets breaking off from the Oort Cloud.The theory that the dinosaurs were killed off by a comet strike is fairly well settled science, although still having many unknowns But you can read about the Chicxulub crater here which has all the hallmarks of a major comet strike 65 million or so years ago, which coincides with the dinosaur s extinction.That said, Randall s concept relies on a theory on top of a hypothesis on top of a theory on top of a hypothesis Yes, there is science behind the premise of dark matter But very little known beyond that right now The entire book seems far to premature to have been published conceptually but seems to have made it to press due to the sexiness of the premise dark matter killed the dinosaurs.Even if her theory has merit, DMATDTAIOTU is just downright boring Not recommended. Bestselling Author Of Warped Passages And Knocking On Heaven S Door And One Of Today S Most Influential And Highly Cited Theoretical Physicists, Professor Lisa Randall Once Again Effortlessly Delivers Fascinating Science To The General Reader Weaving Together The Cosmos History And Our Own In An Expanding Intellectual Adventure Story, Dark Matter And The Dinosaurs Takes Us From The Mysteries Of Dark Matter And Our Cosmic Environment To The Conditions For Life On Earth.Sixty Six Million Years Ago, An Object The Size Of A City Descended From Space To Crash Into Earth, Creating A Cataclysm That Killed Off The Dinosaurs, Along With Three Quarters Of The Other Species On The Planet What Was Its Origin Randall Proposes It Was A Comet That Was Dislodged From Its Orbit As The Solar System Passed Through A Disk Of Dark Matter That Is Embedded In The Plane Of The Milky Way Her Research Challenges The Usual Assumptions About The Simple Nature Of Dark Matter And Demonstrates How Scientists Formulate And Establish New Ideas In A Sense, It Might Have Been Dark Matter That Killed The Dinosaurs.With Her Unique And Wide Ranging Perspective, Randall Connects Dark Matter To The History Of The World In The Broadest Terms Bringing In Pop Culture And Social And Political Viewpoints, She Shares With Us The Latest Findings Established And Speculative Regarding Dark Matter, The Cosmos, The Galaxy, Asteroids, Comets, And Impacts, As Well As Life S Development And Extinctions Randall Makes Clear How Connected The Planet Is To The Makeup Of The Universe, But Also How Fragile Our Place In The Universe, Which Evolved Over Billions Of Years, Might Be.In This Brilliant And Fresh Exploration Of Our Cosmic Environment, Professor Randall Explains The Underlying Science Of Our World In The Breathtaking Tale Of A Universe In Which The Small And The Large, The Visible And The Hidden Are Intimately Related Dark Matter And The Dinosaurs Illuminates The Deep Relationships That Are Critical To Our World As Well As The Astonishing Beauty Of The Structures And Connections That Surround Us It S Impossible To Read This Book And Look At Either Earth Or Sky Again In The Same Way. What is the speed of darkLisa Randall, Dark MatterLisa Randall is smart But she is also able to take topics that most people know very little about dark matter, dark energy, etc and translate the hard science into books for the unwashed masses She s good I believe part of what makes Randall one of a handful of our country s great public intellectuals is her ability to translate and to transfer her specialized knoweldge into books that are largely accesssable to the layman Also, she is curious Part of what makes her a phenominal scientist and not just a very good one, is her curiosity beyond her specialized career She is a theoretical physicist, a cosmologists, a model builder who works well with other theoretical particle physicists and cosmologists But she doesn t stop there She is curious about biology, evolution, geology, politics, art, literature, etc She is a connector She jumps into fields and links things that might have been easily missed She sees a periodicity in large meteor hits, makes an argument that links those asteroids to dark matter and builds a model to explain it She isn t easily kept inside a box Last year I was able to spend a couple days with her when my sister hosted her and some friends in Idaho for the totality It was amazing to watch some basic standard physics moon blocking the sun with one of the most cited living physicists I was literally in the dark with a dark matter expert.At first with the book, I wasn t sure where she was going She obviously needed to lay some basic groundwork about how the univeres was structured, what dark matter was, etc., but then she jumped into a discussion of meteors and comets, mass extinctions, and then we were back to discussing dark matter But she pulled it off She carefully laid the table to explain the contributions she made concerning dark matter One of the things I loved about her writing was she was constantly reinforcing the importance of science, EVEN WHEN IT IS SHOWN LATER TO BE WRONG Randall loves the idea of science than even her own ideas It is easy to adore someone who humbles themselves to the possibility of their theory being wrong, and uses that to further embrace the scientific method I guess I ll let Lisa have the last work to summarize this bookThis book is about the seemingly abstract stuff such as dark matter that I study, but it is also about the Earth s relationships to its cosmic surroundings I have read previous books by Lisa Randall, and liked them well enough, but her new book is in some sense unique, and extraordinary In order to show us how she has come to think that there s a connection between galactic dark matter and Earth s periodic extinctions a somewhat long shot hypothesis she takes us in an amazing tour of our Solar System and the universe, like no other science for the layperson book has ever undertaken It s both a look at how a scientist deeply thinks about ideas and a master class in science.For most of the book, Randall has transformed herself from a physicist to an astronomer and geologist and evolutionary biologist, and effortlessly teaches all of us about the wonders of the universe Even for a jaded College professor and regular reader of this lore I have taught College Physics, Biochemistry, Cellular Biology and Human Physiology and Anatomy for most of my life there are here lots of discoveries and a pervasive, subtle humor that enlivens what could have turned into a dry discussion of geological eras, meteorites and the like, and the biological underpinnings of evolution There s even a bit of fun about Jurassic sic Park and The Big Bang Theory.This book has been an enjoyable surprise to me hadn t liked that much Knocking on Heavens s Door and it places Randall right up there in Carl Sagan s territory A terrific Good Read. Adapted from the Literary Review This book comes garlanded with tributes, headed by the claim Only Lisa Randall can take us on such a thrilling scientific journey I beg to differ Off the top of my head, I can think of half a dozen science writers who could do a better job of describing this particular scientific story and some of them have covered almost all of the material presented here The clue is in the words science writers Randall fits into as particular niche which has recently become over full She is a world renowned scientist, in her case based at Harvard University, and wrote a splendid book about her own area of expertise, Warped Passages So far, so good But since then, like others in a similar situation, she has strayed, or been encouraged to stray, authorially, into territory outside her own specialist area, territory that is already better covered by writers who understand science but, at least as importantly, are gifted communicators George Musser, in her homeland, and Brian Clegg, on this side of the pond, are two that spring to mind If it were not for her academic status, Randall s latest book would pass by as just another rather humdrum account of the origin and evolution of the Universe and probably I would not be reviewing it Its only claim to be special is a rather desperate one the tenuous titular link between dark matter and the fate of the dinosaurs, which is no than a highly speculative variation on an idea that has been around for decades That idea is that as the Solar System bobs up and down on its route around the Galaxy, and repeatedly crosses the disc of the Milky Way like the needle of a sewing machine bobbing up and down through a piece of cloth, gravitational forces shake loose comets from the region known as the Oort Cloud, far beyond the orbit of Pluto Some of these comets fall inward towards the Sun, where they may collide with the Earth, with devastating consequences The idea is based on some rather dodgy statistics linking alleged periodicities in so called mass extinctions of life on Earth including the death of the dinosaurs some 65 million years ago with the periodicities associated with the bobbing movement of the Sun in its orbit around the Milky Way The statistics are made no less dodgy by Randall s wild suggestion even Randall herself calls it a speculative scenario that a layer of dark matter within the galactic disc, like the meat in a hamburger, is what provides the gravitational tug that shakes the comets loose This does, of course, provide an ideal opportunity to discuss the nature of dark matter, and its role in the evolution of the Universe But any scientifically aware person must by now be familiar with the idea that the kind of stuff we are made of in essence, atoms makes up only a small proportion of the matter in the Universe, so that stars and galaxies are embedded in a sea of invisible dark matter, which interacts with our kind of stuff only through gravity Anyone who has an interest in cosmology also knows about dark energy, and the discoveries about the cosmic background radiation recently made by satellites such as NASA s WMAP and ESA s Planck Randall covers all this, and a discussion of the Solar System and our place in it, in workmanlike fashion But workmanlike really isn t good enough, when the stories have been covered so often, and so well, already I quite like the personal vignettes, such as Randall s description of meteor watching in the Rocky Mountains But these ought to be the icing on the cake, not the highlights, of a book like this Even the discussion of dark matter is over familiar, except for the minor and unconvincing twist in the tail A bit less than the last quarter of the book actually addresses the topic of the title I m being generous arguably less than half that and a large chunk of this is taken up with telling us, with commendable honesty, about all the uncertainties in the claim Dinosaurs sell books as do cats , and I don t blame Randall for trying to sex up her subject But all the new and interesting though probably wrong stuff here could have comfortably been encapsulated in an article for Scientific American Who might benefit from the book A complete newcomer, maybe the proverbial teenager who as yet knows nothing about the Universe and the place of the Earth in space Who will be disappointed by it Anyone interested in dinosaurs And what should the book have been called The Speed of Dark, as any Terry Pratchett fan could tell you It would not be fair to say that I am disappointed by the book, because I had low expectations But it is fair to say that those expectations have been fulfilled The real disappointment is that if she had not been busy writing this very average account of the Universe, Randall could have been concentrating on her research, which really is thrilling There is an expression about cobblers and lasts which is apposite. Randall offers an exotic hypothesis to explain the demise of the dinosaurs 66 million years ago She argues that the solar system passing through a disk of dark matter in the galactic plane perturbed Oort cloud objects resulting in a large comet crashing into earth She admits the theory is highly speculative and says her real purpose is to share the underlying science To make her case she ties together diverse scientific disciplines including cosmology, particle physics, astronomy, geology and paleontology Randall starts by taking us through the formation of the universe with an emphasis on the role of dark matter Dark matter interacts with ordinary matter and itself solely through gravity as far as we know There is five times as much of it as ordinary matter and it is critical to the structure and arrangement of galaxies Our galaxy, the Milky Way, is a disk 130,000 light years wide and 2,000 light years thick It resides in a spherical halo of dark matter that extends 650,000 light years across The sun lies 27,000 light years from the center and circles the galaxy every 240 million years.Next Randall digs into the Solar System s structure describing the categories, compositions, distributions and behaviors of planets, dwarf planets, asteroids, meteoroids, dust and especially comets Short period comets less than 200 years may be guided by the Kuiper Belt but originate in the Scattered Disk The Kuiper Belt is the region beyond Neptune Neptune is 30 AU from the sun AU stands for Astronomical Unit, the distance from the center of the earth to the center of the sun The Kuiper Belt is a doughnut shaped area containing dwarf planets including Pluto and smaller icy bodies extending out to 55 AU Past that, out to 100 AU, lies the much sparsely populated Scattered Disk which also has minor planets and icy bodies These frozen gas bodies can become comets when perturbed from unstable elliptical orbits Long period comets than 200 years originate in the Oort cloud, which extends from 1,000 to 50,000 AU from the sun, almost a light year The Oort cloud is too far away to observe so it is considered hypothetical The Oort cloud extends to the end of the Sun s gravitational ability to hold objects Such lightly bound objects are easily dislodged from their orbits Meteoroids and dust regularly enter earth s atmosphere Larger asteroids and comets are less frequent but far significant The largest recorded event in 1908 in Russia was from a 50 meter wide object that exploded with the equivalent of 10 to 15 megatons of TNT or about 1,000 times of the Hiroshima bomb destroying 2,000 square kilometers of forest Randall identifies 26 impact craters formed in the last 250 million years that exceed 20 kilometers wide indicating events resulting in global damage Since the earth is 70% ocean and erosion and other factors hide craters, many have occurred Randall explains the methods geologists use to determine that a crater has an extraterrestrial cause.Randall describes the ways paleontologists reconstruct the past to determine that a mass extinction has taken place There have been five big ones since the rapid rise of complex multicellular life 540 million years ago The biggest was 250 million year ago, the Permian Triassic event which killed off 90% of species Fifty million years later another event enabled the dinosaurs to take charge and then 66 million years ago another event eliminated them and paved the way for us mammals Today we are on the brink of a human caused sixth extinction The Cretaceous Paleogene event of 66 million years ago that killed off the dinosaurs was caused by a comet Randall explores the years of detective work by geologists that went into proposing and then confirming this The impactor hit at the edge of the Yucatan peninsula of Mexico leaving a crater 150 kilometers in diameter This 10 15 kilometer wide object traveling at 20 kilometers per second released an energy equivalent of 100 trillion tons of TNT, a billion times than the bomb dropped on Hiroshima Tidal waves and seismic waves rippled around the globe Poisonous fumes filled the atmosphere Fires broke out everywhere followed by a global winter from an atmosphere filled with debris blocking the sun s rays Birds, burrowing mammals and some other fortunate species would hang on to survive Randall examines the proposals that these impact events occur frequently at regular intervals and settles on a period of 32 million years To support her theory Randall explores current ideas for dark matter The most common is WIMP, Weakly Interactive Massive Particle The LHC Large Hadron Collider , which successfully found the comparably massive Higgs boson, has been unable to find these proposed additions to the Standard Model Another is Asymmetric Dark Matter which like WIMPs allows for a small yet to be detected interaction with ordinary matter Another candidate particle is the axion which has already been suggested to solve other problems with the Standard Model, but none have been detected Other ideas such as neutrinos or simply unseen ordinary matter such as mini black holes have been pretty much disproven Randall highlights the many ongoing experiments that place detectors deep in the earth to block out interference so that the weak interactions of these particles might be recorded Randall looks at how well dark matter s gravitational influence lines up with the universe s galactic structure She notes that the distribution of dark matter in dwarf galaxies and galactic centers is less than predicted She claims her hypothesis that a small percentage of dark matter interacts with itself, mimicking at least partially the behavior of ordinary matter, explains these anomalies The WIMP theory holds that the dark matter particle is much heavier than a proton Randall uses this in her model to support her partially interacting dark matter forming a disk in the galactic plane that is 100 times thinner than that formed by ordinary matter This is key to its periodic disruptive gravitational impact on the Solar System s Oort cloud Unlike the wider galactic plane of ordinary matter in which the solar system always resides, the solar system moves in and out of the dense dark matter disk as it weaves up and down in its orbit around the galaxy The gravity of this thin dense disk would be enough to perturb Oort objects sending some towards earth This movement of the Solar System ties to Randall s periodicity of 32 million years The Solar System entered the proposed dense dark matter disk two million years ago, add in two complete cycles, and you are at 66 million years ago.So what are we to make of this bizarre theory that makes unsupported assumptions about the nature of dark matter particularly that at least some of it must interact with itself in order to form the proposed disk Randall is careful to craft her model so that it conforms to known measurements, but this hardly makes it true It s a big stretch We could call it a shot in the dark But to me the real value of the book is not in the theory, it is what I learned as Randall took me through the science she used to build it I learned a lot about dark matter, even if I still have no idea what it is I learned how it influences the structure of ordinary matter I learned the many theories and experiments underway to uncover its nature I gained a new appreciation for the entirety of our Solar System I now visualize the entire Solar System including its far flung halo of Oort objects moving through the galaxy Before, I just pictured the planets revolving around the sun And even if dark matter was not the trigger I find it fascinating that our presence on earth has been determined by an object coming from a part of the Solar System that has never been observed. Dark Matter and the Dinosaurs was over my pay grade I m afraid I understand only half of the book completely the rest was an exercise in futility However, it seems up to date and on the cutting edge of theory as much as a non scientist reader like myself, who reads pop science magazines, can comprehend National Academy of Sciences member Lisa Randall s book was published in 2015 Dark Matter and the Dinosaurs , one of many books she has written, recognized for their quality in describing the high end science Randall is exploring, is a thorough physical forces walkabout on the creation of the Earth, the solar system and the Universe as only someone who has studied theoretical particle physics and cosmology at Harvard University can do it.While I did not see any mathematical equations in the book, her explanations are based on deductions from sussing out the science from the mathematics which describes how the universe functions, and the almost understanding of how it all started, and brief descriptions of how particles, atoms and elements interact combine and separate to illustrate the why of scientists deductions, along with graphs that chart and examine the measurements taken by various high tech instruments and low tech satellite cuties scooting around in the Solar System.Whew The amount of detail and facts this woman must be able to juggle in her head while drinking coffee must be astronomically huge Literally I suspect the book is a wonderfully enlightening read, but due to the low wattage of my brain cells, I can only say I enjoyed the challenge of reading it I was able to pick out bits which echo what I ve been reading in articles which talk down to readers, but Randall s explanations filled in many blanks for me.I recommend reading this in depth book several times.Check out this superior review Our Souls are DarkIt is an increasingly accepted speculation that souls might in fact be made of dark matter According to our latest models, they dark souls condense first and allow life to settle down around them Of course, they can t be detected since they are not detectable by ordinary matter science On death, the souls depart from the body, and can go to heaven cause rebirth via re agglomeration depending on religious practices of the ordinary matter person associated with the soul It is not yet fully understood how religious practices affect the dark matter core of a person However, we do know that the souls get affected by a lifetime of sins, penance, charity, etc It is accepted by now that no life can form without a dark soul though some scientists still like the older idea that a soul is required only for higher life forms, probably only humans Lower life forms can agglomerate without the gravitational religious pull exerted by the soul core The source of this mysterious force that is akin to gravity but applies only to life forms is yet to be discovered It is exciting to consider that life might be the only source of interaction between dark and ordinary matter, outside the even mysterious realm of gravity This allows us to speculate that ghosts might be real In certain religions, certain required practices being not performed would mean that the soul core is not fully freed from its person form This makes it unstable and dangerous, in a limbo state between dark and ordinary matter, and causes it to react in unpredictable ways with ordinary matter sometimes violating the laws of ordinary matter physics It is not entirely clear how this comes about Dark matter souls normally interact with entirely new forces and particles that do not interact with ordinary matter But it has been observed over time that religion can have an effect on this It is a matter of great speculation how nature of reality is altered by the gravitational religious forces that seem to transcend the dark ordinary boundary and allow some diffuse interactions A new temple is proposed to be built near CERN to test the interactions and to identify the carriers of these interactions We anxiously await the results We are also hoping to bump into a few celebrity souls ghosts over there It is a whole new world that awaits us I really enjoy science books that are well written, by a scientist who has personally contributed to the field This book certainly fits into this category, as Lisa Randall is a good writer This book relates some of the research that she and her collaborators have been doing Much of the book sets the stage so that lay readers can understand her speculative new hypothesis, and put it into perspective Randall s hypothesis is that dark matter is not exclusively arranged in a big halo around the Milky Way galaxy There is a distinct concentration of dark matter in the central plane of our galaxy As our solar system periodically oscillates up and down with respect to the central plane, it is especially perturbed by the concentration of dark matter The period of this oscillation is about 32 million years Comets in the outer reaches of our solar system are perturbed in their orbits They are so far from the sun that a small gravitational perturbation can kick a comet into an orbit that intersects the inner solar system, in the vicinity of the Earth One such comet collided with the Earth about 66 million years ago, creating a crater in Mexico s Yucatan peninsula The comet was 10 or 20 kilometers in diameter, and was responsible for the extinction of most of the living species on Earth, including the dinosaurs.Now, this hypothesis might be totally wrong But, Randall explains how she tested it, and how a future spacecraft mission GAIA will provide additional experimental tests In fact, the GAIA spacecraft mission will measure the positions and velocities of billions of stars in our galaxy It is very fortuitous that the spacecraft was being launched at just the right time, and with exactly the purpose that will test Randall s hypothesis She notes how very lucky she is in this regard.The book reads a bit like a detective story Lisa Randall takes the reader step by step through the process she and her collaborators took, to formulate and test their hypothesis This is science writing at its best, because science is not a bunch of facts Science is a process And this book shows exactly how the process can work Most notably, Randall shows how serendipity can often play a role in science Fortunate coincidences can come together at opportune moments, guiding the research to productive results.Some reviewers find this book to be somewhat dry I disagree it is written in a straightforward style, with none of the cutesy stuff that some science journalists stick in to dumb down their books and.to bring in mass readership That s not to say that the book is devoid of humor I got a big kick out of the photograph in Figure 35 I won t spoil your fun by giving it away you will have to read the book to see it My only complaint about the book, is that its organization seems to be a bit strange at times The full synopsis of the hypothesis does not appear until the very end of the book I guess, that is how it was intended, sort of the denouement of a detective story And, I was almost ready to write a scathing review, because a clear explanation of the hypothesis seemed to be missing from the book But in the end, the full story is told, and it all makes sense Also, I must remark that this book covers a broad range of fields particle physics, astronomy, cosmology, and paleontology I heartily recommend this book to everyone who is interested in learning about how modern science is really done these days.

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