What is Real? The Unfinished uest for the Meaning of uantum Physics (DOWNLOAD)
Surement ie the Copenhagen Interpretation If the latter this would in turn imply that in certain situations ie where particles were uantumly entangled information about these properties would be transmitted instantaneously ie faster than the speed of light and locality would fail Naturally Einstein preferred the situation where M was incomplete and locality was upheldDavid Bohm later derived a model of M that was completely consistent with the maths of the Copenhagen Interpretation but did involve hidden non local variables ie at any particular moment a particle has a definite momentum energy spin etc As a bonus this Bohmian interpretation gave simple explanations of classic problems like the double slit experiment as well as M entanglement but perhaps because it involved non locality or because it contradicted the Copenhagen Interpretation was largely dismissed and forgotten Hugh Everett looking for a uick doctoral topic decided to avoid the measurement problem altogether by supposing the wave function never collapsed and thereby developed what has become known as the Many Worlds interpretation of M Naturally his work was also ignored by the physics establishment at the time and he had to radically reedit his thesis in order to passLater John Bell a particle physicist at CERN who by his own account worked on M foundations on Sundays developed a theoretical test to see if local hidden variables could exist within M His paper published in an obscure ournal was eventually tested years later at Berkeley for the first time in the early 1970s and showed that non locality was upheld ie there were no local hidden variables God does play with dice What this means for the World is hard to get your head around and I oin my better Einstein in thinking this is a very weird result indeed It is shocking to learn that the postdoc who did these brilliant experiments was unable to get tenure afterwards because this work was regarded as uasi worthless by the general physics community in the 1970s In an irony of fate this very non locality is the very basis for modern uantum computingStrongly recommended 5 stars A truly fantastic lucid overview of the competing theories that purport to explain uantum mechanics Becker takes an interesting approach that I ve never read before which is to put all the different theories into historical context We learn a great deal about both the philosophical context and personalities that surrounded supported and challenged the competing theories What is at stake here is our understanding of the very nature of realityAlthough I ve read a great deal about uantum theory this book was an eye opener There are currently three leading theories to explain the Schrodinger Euation and what it says about the nature of the universe The Copenhagen Interpretation which was the first explanation and the most widely known the de Broglie Bohm Pilot Wave Theory and the Many Worlds Interpretation There are several others out there as well but these are the leading three at present and the ones that Becker spends the majority of his book explaining There is a fourth for example that proposes the random collapse of the wave function but it is not very popular at the moment It seems a bit gimmicky to me but it can t be dismissed on that basisBecker demonstrates that although Copenhagen is still the most widely accepted by physicists it has tremendous gaping holes of logic in it that fail to ustify its popularity Becker educates us thoroughly on how it came to be so popular despite the weakness of it Much of it has to do with the cult of personality around key physicists who promoted it when it first came out along with various political events cultural and philosophical currents that complemented this theory Since then the challenges of understanding uantum mechanics have kept a kind of inertia among physicists which creates reluctance for them to consider new theories Einstein didn t trust the Copenhagen interpretation and invented thought experiments that challenged it The story goes that Niels Bohr overcame and dismissed Einstein s objections and won the debate But as Becker presents it in fact Bohr was a confusing muddled communicator and a slow thinker who never actually understood Einstein s thought experiments and only rejected them rhetorically not through actual logical debate In the end much of the defense of Copenhagen was simply assertionEinstein had two primary objections to the Copenhagen interpretation The first was non locality or what he called spooky action at a distance He said there was no reason to trust that particles can instantaneously move from one location to another or instantaneously communicate over vast distances as is reuired by the Copenhagen Interpretation He also objected to the mushy undefined nature of how an observation causes the collapse of the Schrodinger Wave function Do events not occur in deep space if they Aren T Being Observed And If Not Then How Do t being observed And if not then how do processes continue on in time until they are observed For example imagine an unobserved sun exploding far from any life forms I million years later it collapses into a white dwarf star Imagine no observer has seen the sun for the first million years but then a space ship whizzes nearby and sees the white dwarf star Did the sun not exist for the first million years of its explosion but then instantaneously leaps into white dwarf star state as if it had been observed in the past million years You can see the absurdity of this It would have to instantaneously assume a state and also instantaneously assume one million years of past history Does observation reuire consciousness to read a piece of data Or does a mouse collapse the wave function The theory can t answer that uestion There is also another big hole in the Copenhagen Interpretation which is that it must posit a distinction between the uantum world and the classic world Right now the theory proposes that classical objects those that obey Newtonian physics are ustbigger And small objects obey uantum effects An observation must be enacted by a big object that is classical in order to collapse the wave function But Copenhagen can t explain why bigger objects aren t subject to uantum effects and where the boundary is between big and small Nothing in the Schrodinger Euation itself ever signals that a collapse should occur As far as the Schrodinger Euation knows particles will continue in their undefinable states forever Measurement is invented as an outside ustification for finding particles somewhere rather than everywhere at onceCopenhagen seems bankrupt to me Too many holes are unexplained by itit is clearly incomplete The Pilot Wave Theory plugs a few of the holes although it still suffers from non locality but in fewer cases than Copenhagen does In general Pilot Wave theory solves the issue of the particlewave duality Particles ride on waves essentially so their behavior is not nearly as mysterious as it is in Copenhagen Pilot Wave Theory does a great Izzy Wizzy job of explaining the mysterious double slit experiment for example Particles have definite locations within an atom but weust can t see them They aren t mysteriously smeared everywhere at the time THEY ARE MOVING ALONG FOLLOWING THEIR are moving along following wave and are simply found where they are found when measured An observer isn t reuired per se so it solves the measurement problem But it still reuires non locality in some situations Some physicists still believe Einstein was wrong and the world may not be local Particles may make faster than light instantaneous changes Since Pilot Wave theory is euivalent to the Schrodinger Euation mathematically it is worth considering The Many Worlds Interpretation has become much recognized in recent years in popular culture as well as physics circles but there still remains a lot of resistance to it as a theory because it reuires you to adopt a very very very strange view of reality Really the Copenhagen explanation is also very very strange but because it maintains a certain mystery we can never know it perhaps leaves some of that strangeness disguisedOn the plus side the Many Worlds Interpretation does in fact eliminate non locality as an issue Particles do not in fact ever instantly assume positions or change positions instantly nor do they communicate with their pasts to assume some certain state Many Worlds also solves the observer issue No observation is reuired It also explains the related measurement issue Similarly no measurement is reuired to collapse the Schrodinger Euation Nor is there any need to distinguish between classical or big objects and small or uantum objects Everything is subject to uantum effects all the time When a uantum particle interacts with another larger object such as a measurement device they become entangled and unite into a larger and complex Schrodinger Euation There is no collapse only constant entanglementIt s weirder than that though In fact it proposes that every single uantum state that has ever existed breaks off into a separate universe The entire universe is an infinite multiplicity of universes that are all united as one giant uantum Schrodinger Euation Every single state spins off as a new universe Now that is supremely weird But mathematically it is also euivalent to the Copenhagen Interpretation and produces the same results There are some challenges with the meaning of probability however so it s not a fully solved model for the universe But it certainly answers many uestions that Copenhagen doesn t And it also cures non locality which Einstein believed was impossibleAll that said Becker points out that it is uite possible that a new interpretation could arise that would supersede all these as well but he encourages the scientific pursuit of the meaning of the Schrodinger Euation and demonstrates why there is so much value in pursuing these mysteriesWhat a great book Recommended for anyone who enjoys cutting edge physics and written in a fashion that seems comprehensible to the layperson What is real This ought to be a uestion of burning interest to almost everyone and yet for some reason hardly anybody over the age of seventeen seems to take it seriously If you ask the adults no one s sure whose responsibility it is They send you over to talk to the sociologists who shrug their shoulders sorry guv nuffin to do wiv us Try philosophy they re ust down the street The philosophers look embarrassed and explain that yes absolutely they used to be in charge of it but now it s been handed over to physics The physicists tell you that of course they know the answer there is no such thing as reality If you aren t happy with that go and talk with the sociologists And round you go again This book I am pleased to say does take the uestion seriously Rather than limiting himself to one single viewpoint which as we ve seen lets it get away Adam Becker pursues all three lines of investigation simultaneously and manages to present something which looks surprisingly like an answer It s a complicated answer and you need a three hundred page book to explain it properly but I would summarise it like this About a hundred years ago a group of physicists made some astonishing discoveries This work which soon started going by the name of uantum mechanics had enormous philosophical implications in comparison the Copernican revolution was no than a minor footnote It showed that the nature of reality was completely different from what had previously been believed It was also unfortunately rather difficult to understand and could only be explained well in mathematical language Even worse it turned out to be a source of incredible military and economic power it made possible the development of weapons and technologies that had previously not even been dreamed of Power as is well known corrupts and this new power corrupted at every level In particular it corrupted intellectually Physicists who in the 1920s had been familiar with philosophy and well disposed towards philosophical ways of thinking became arrogant and impatient with the philosophers What were they doing sitting around dreaming about eternal verities when physicists had important work to do The physicists decided they could take care of the philosophy themselves They cobbled together some theories from the currently fashionable positivist school and breathed a sigh of relief We don t need to worry about what reality is there is no such thing as reality and the mere fact that you ask the uestion shows you are an ignorant layman We have a picture of what happens in uantum mechanics which we call the Copenhagen interpretation and it s the only possible answer We have mathematically proved it A few people whispered that the proof seemed to have a hole in it and the Copenhagen interpretation didn t actually make sense but they were ignored Who cared what these crazy dissidents thought when physics departments were being showered with money by people who wanted magical devices The math worked it didn t matter what it meant In a phrase which came to encapsulate this whole world view shut up and calculate The philosophers who should have been keeping an eye on things under the academic world s informal separation of powers system had lost all confidence They no longer had any power When they tried to object they were slapped down by the physicists no one cares what you say when you don t understand the complex math on which uantum mechanics is based Physicists who did understand the math and still had a philosophical outlook were contained in other ways If they tried to publish work it was usually rejected as not real physics If they persisted they were labelled as unemployable and refused promotion or worseIt s an absolutely fascinating chapter in the development of human thought and Adam Becker who s done a huge amount of background research explains it very well He starts off with a uote from Ursula Le Guin and if you re a fan of The Dispossessed you ll soon recognise the story this is Shevek but not as a fictional character Read it and find out what s really been going on. Ng the status uo long meant professional ruin And yet from the 1920s to today physicists like John Bell David Bohm and Hugh Everett persisted in seeking the true meaning of uantum mechanics What Is Real is the gripping story of this battle of ideas and of the courageous scientists who dared to stand up for trut. ,
Of the developments in modern scientific thinking are in lagging mode This is because of the extreme complexities of the formalisms created to describe the reality as seen by human observers with a certain evolved sense of perception The modern philosopher has to tread wearily through the theory before emerging tired and almost at wit s end to be in a position to even expound a valid opinion least of all an emerging new philosophy on the ontological basis of the uantum world This is the first time I ve read a book on uantum Mechanics wherein three of the major outlier physicists appear David Bohm Hugh Everett III and John Stewart Bell Here s a brief excerpt of my review of What is Real for Nature magazine which was ust published today Please check out the full review here hell broke loose in physics some 90 years ago uantum theory emerged partly in heated clashes between Albert Einstein and Niels Bohr It posed a challenge to the very nature of science and arguably continues to do so by severely straining the relationship between theory and the nature of reality Adam Becker a science writer and astrophysicist explores this tangled tale in What Is RealBecker uestions the hegemony of the Copenhagen interpretation of uantum mechanics Propounded by Bohr and Werner Heisenberg in the 1920s this theory holds that physical systems have only probabilities rather than specific properties until they re measured Becker argues that trying to parse how this interpretation reflects the world we live in is an exercise in opacity Showing that the evolution of science is affected by historical events including sociological cultural political and economic factors he explores alternative explanations Had events played out differently in the 1920s he asserts our view of physics might be very differentBecker lingers on the 1927 Solvay Conference in Brussels where 29 brilliant scientists gathered to discuss the fledgling uantum theory Here the disagreements between Bohr Einstein and others including Erwin Schr dinger and Louis de Broglie came to a head Whereas Bohr proposed that entities such as electrons had only probabilities if they weren t observed Einstein argued that they had independent reality prompting his famous claim that God does not play dice Years later he added a gloss What we call science has the sole purpose of determining what is Suddenly scientific realism the idea that confirmed scientific theories roughly reflect reality was at stake Interdisciplinarity between scientists philosophers and neuroscientists will eventually crack the well deciphered code of realityPlease note that I have put the original German text to the end of this review Just if you might be interestedThe game of knowledge acuisition has always been played back and forth between three groups The philosophers scientists and recently the neuroscientists Philosophers can design the inspirational ideas for the other two groups in the field and make colorful mixtures together Scientists work on experiments detection methods and ever better instrumentsThe case of neuroscientists and brain researchers is complicated They have the option to observe the thoughts of physicists and philosophers live in practice What makes them even interdisciplinary than the two other groups Because all together the theories for consciousness its function and the forces acting on it can be observed For instance which neuronal level defines which state of consciousness in reality Which in turn raises new uestions for the philosophers who pass these on to the natural scientists The fact that uantum mechanics was also the key to unleashing atomic forces is often overlooked in the face of spooky distant effects But it were these theories that created the foundations for further insights in physics and astrophysics which in turn inspired the earliest nuclear weapons If such potential could be used than 70 years ago then what would happen in 700 years What kind of weapon would that be that doesn t use the clumsy and sluggish atoms but the even smaller bricks of reality Which chain reactions could be unleashedHow long the misery of the science war around the Copenhagen interpretation served as an impediment on one of the significant fields of research is one example of discord in science To remain serious and publishable researchers had to pay attention to their reputation and above all circumvent the vague hypotheses of philosophy and some humanities And to prevent any ideological debates and vendettas between oppositely arguing scientists or to uestion their own belief too critically They should only research in a given direction under a certain paradigmFrom soon 100 years ago with the debate beginning in the early 20th century until now this was a reason for the disunity of many researchers Besides there was the danger of losing their own life s work legitimacy If even Einstein doubted and sometimes despaired because that much dissonance existed between his theories and the hypotheses Or if like John Bell one ust got ingratitude and problems for working out the basics of uantum computing What s it was economical to begin with real applications than marketing ust ideas which finally discredited the philosophersAs so often one has tended to think in extremes Instead of finding insight in the middle between and perhaps the solution too In the case of uantum physics one extreme is the opinion that in observation there is only one unpredictable random reality One of two conditions or possibilities and Seeds Stuck In The Tree just one form of reality at the same time for an observing person Indeed the misunderstood choice between two conditions or properties and also complementary theories But definitely not that which is explainable or examinable The long prevailing Copenhagen interpretation Bohr that blocked other approaches for a long time This one random state may perhaps be complementary to another state and thus there is no real reality because we cant observe it Point and end of the debate The other party fundamentally uestions the validity of the accessible reality and suspects unknown factors Einstein The beginning of a dispute that continues to this dayEither everything is so clear and easy or everything isust fake and signifies nothing So everything almost solipsistic only related to the ego or the total dissolution of ego Absolute behavioral patterns of particles without individual properties or hidden variables that God uses to throw dice A dead or alive cat or endless variations of necromantic zombie cats Determinism or variations of free will in all orders of magnitude Predetermination by a higher entity or it s own decision Two pretty opposing points of viewIt is difficult to reconcile both understandable experiments and mathematics as well as pure thought experiments Now after a long period of stagnation the time has come to test the theories in practice thanks to better technology And subseuently rehabilitate the advocates of the once ridiculed theses But there is also the option that different approaches are right in different circumstances because there is not Little Fish And Big Fish just one realityToday 2018 the allegedly specific hypotheses are under attack by two sides On a large scale by gravitational waves black holes and on a small scale by neutrinos uanta Todayust as Bohr many researchers make the mistake of defending their doctrine like a clucking hen on top of their eggs and aggressively picking each helpless doctorand or student who dares to choose a different point of view Funny to look at but in the field of tragedy Because the real greatness is to revise a life s work occasionally and to search with the obtained wisdom for the new better theory of everything Because incomplete hypotheses are not perfect formulas but only auxiliary vehicles to finding a better theoryInterdisziplinarit t zwischen Naturwissenschaftlern Philosophen und Neurowissenschaftlern wird irgendwann den gut dechiffrierten Code der Realit t knackenDer Spielball der Erkenntnis wird seit Don T Go There jeher zwischen drei Gruppen hin und her gespielt Den Philosophen Naturwissenschaftler und seit ngerer Vergangenheit den Hirnforschern Philosophen k nnen die inspirierenden Ideen f r die zwei anderen Gruppen in der Praxis konzipieren und bunte Mischungen zusammen basteln Naturwissenschaftler t fteln an Experimenten Nachweisverfahren und immer besseren Instrumenten Der Fall der Neurowissenschaftler und Gehirnforscher ist diffiziler Ihnen er ffnet sich die Option die Gedanken der Physiker und Philosophen in der Praxis live zu beobachten Was sie noch interdisziplin rer als die 2 anderen Gruppen macht Denn sowohl die Theorien f r Bewusstsein seine Funktion als auch die darauf wirkenden Kr fte lassen sich beobachten Etwa f r welches neuronale Level welcher Grad an Bewusstsein *Realit T Definiert Was *t definiert Was neue Fragen f r die Philosophen aufwirft die diese an die Naturwissenschaflter weiter reichenDass r die Philosophen aufwirft die diese an die Naturwissenschaflter weiter reichenDass der uantenmechanik auch der Schl ssel zur Entfesselung der atomaren Kr fte lag wird angesichts von spukhafter Fernwirkung gern bersehen Doch schufen erst diese Theorien die Grundlagen f r weitere Erkenntnisse der Physik und Astrophysik die wiederum die ersten Kernwaffen inspirierten Wenn vor ber 70 Jahren derartiges Potential freigesetzt werden konnte was dann erst in 700 Jahren Was w re das f r eine Waffe die sich nicht den plumpen und tr gen Atomen sondern der noch kleineren Ebenen der Realit t bedient Wie lange die Misere um den Wissenschaftskrieg der Kopenhagen Interpretation als Hemmschuh gedient hat zeigt einen der gro en Zwiesp lte der Forschung auf Um seri s und publizierbar zu bleiben mussten Forscher auf ihre Renommee achten und vor allem die Hypothesen der Philosophie und mancher Geisteswissenschaften umgehen Und um etwaigen ideologischen Debatten und Vendettas zwischen gegens tzlich argumentierenden Wissenschaftlern vorzubeugen oder ihren eigenen Glauben nicht zu kritisch zu hinterfragen Sie d rften nur in eine vorgegeben Richtung unter einem Paradigma forschenDas war vor 100 Jahren mit Beginn der Debatte bis weit ins 20 Jahrhundert hinein ein Grund f r die Zerrissenheit vieler Forscher Noch dazu wenn dabei die Gefahr bestand eigenen Lebenswerken die Legitimation abzuerkennen Wenn selbst Einstein zweifelte und mitunter verzweifelte weil genau diese Dissonanz zwischen seinen Theorien und den Hypothesen bestand Oder wenn man wie John Bell nur Undank f r die Erarbeitung der Grundlagen der uantencomputer bekam Noch dazu kam dass sich konomisch mit realen Anwendungen mehr anfangen lie als mit der Vermarktung von Ideen was die Philosophen endg ltig diskreditierteWie so oft tendierte der Mensch dazu in Extremen zu denken Anstatt im Mittelweg sein Gl ck und vielleicht die L sung zu finden Im Fall der uantenphysik ist das die Meinung dass es in der Beobachtung nur die eine unvorhersagbare zuf llige Realit t gibt Den einen von zwei Zust nden oder M glichkeiten beziehungsweise nur eine Form von Realit t zur selben Zeit f r eine beobachtende Person Zwar schon die unverstandene Wahl zwischen zwei Zust nden oder Eigenschaften und auch komplement re Theorien aber definitiv nicht mehr als das Die lange vorherrschende und andere Ans tze blockierende Kopenhagener Interpretation Bohr Dieser eine zuf llige Zustand kann vielleicht komplement r mit einem anderen Zustand sein und damit gibt es keine echte Realit t Punkt und Ende der Debatte Die andere Partei zweifelt die Aussagekraft der zug nglichen Realit t grunds tzlich an und vermutet unbekannte Faktoren Einstein Der Beginn eines bis heute andauernden StreitsEntweder alles ist so was von eindeutig oder alles ist nur fake und Schall und Rauch Also alles fast solipsistisch nur auf das Ego bezogen oder die totale Aufl sung von Ego Absolute durch Naturkonstanten bestimmte Verhaltensmuster von Teilchen ohne individuelle Eigenschaften oder versteckte Variablen nach denen Gott doch w rfelt Eine tote oder eine lebendige Katze oder unendliche Variationen von nekromantischen Zombiekatzen Determinismus oder Variationen von freiem Willen in allen Gr enordnungen Vorbestimmung durch eine h here Entit t oder eigene Entscheidung 59th book for 2018A very interesting and accessible book on uantum ontologyWith NO MATH BECKER TAKES THE READER math Becker takes the reader through nearly a hundred years of back and forth debate as what uantum mechanics implies about the universe we live in The history itself is fascinating I had no idea blush that Heisenberg of uncertainty fame was actually a Nazi who headed the Nazi s atomic bomb project which according to Heisenberg postwar was unsuccessful as he was really a nice guy who didn t want to blow up things and according to Becker was incompetent According to Becker Heisenberg was actually the one who coined the Copenhagen Agreement in the postwar period as a way of cementing his role in the foundation of Ms and upgrading his status post Hitler and by doing so made it seem there was a standard interpretation when there wasn t Einstein who I had been raised to think of as ust never getting M comes across as particularly sharp in his critiue and was concerned about the implications of non locality that he saw lurking at the heart of the standard interpretation of M which is of course at the heart of Bell s ineuality theorem M s grandfather Bohr comes as a bit of an arsehole stopping any dissent into his standard positivist interpretation of M His waving away of the measurement problem of there being two worlds a M world of the small and a classical world of the big can be seen in retrospect as incoherent and vastly damaging to the fieldIf I understood things correctly Einstein s major concern with the Copenhagen Interpretation of M was that not only were a particle s properties momentum energy etc unknown until the collapse of M wave function they in didn t exist according to the Copenhagen Interpretation until that point Einstein saw that this led to two possibilities either M was incomplete and these properties existed but were unmeasurable ie there were hidden variables God doesn t play dice or the nature of the properties was fixed at the time of mea. Erpretation and dismissed uestions about the reality underlying uantum physics as meaningless A mishmash of solipsism and poor reasoning Copenhagen endured as Bohr's students vigorously protected his legacy and the physics community favored practical experiments over philosophical arguments As a result uestioni. One of the best science books I ve ever read and ust what I was looking for after I fell down the wikipedia uantum physics rabbit hole last week and was intrigued and confused as hell I had half an existentialist crisis because I suddenly started doubting determinism Adam Becker gives both a historical run down of how the theory of uantum Physics came to be and an explanation of the different interpretations thereof I tend to think of physics as a hard science and this was such an eye opener in how much ignorance cultural norms and customs psychology and trends come into play when it comes to what we count as scientific and not and which theories we take seriously those that already fit our perceived notions and which not Coming from the field of philosophy I really appreciated and admired Becker s analytical approach and his explanation of analytical and continental philosophy You can really tell he s studied both physics and philosophy Although the book tries to give a or less neutral overview Becker s clearly not a fan of the classical Copenhagen interpretation Neither am I but of course I ust read a biased account of it so that might be part of it I m no less confused about uantum physics than I was before but I have learnt a lot and I m even intrigued now Although I m really glad this books was virtually free of maths and easy to read I do wish I could understand of the maths behind the theory If this book were a meal it would be bursting with such flavor that you could not help going back for seconds Indeed I read it a second time and chose to listen to Sean Carroll s Mysteries of Modern Physics lectures from The G Gee whiz What is real How the Heisenberg should I know This book left me in doubt about our my reality than before I read it but I guess that s a good thingWhen you hear the words uantum Theory and you only have a vague notion about some cat in a box that s neither dead nor alive or perhaps both at the same time but want to learn this is the book for you Although T usually involves some rather complicated and evolved maths this text gets by completely without it Instead you ll get a coherent picture about the history philosophy and naturally the science around T from the early stages to current time Although the euations and formulas of T obviously can predict events and ualities of the universe with astonishing precision even after than ninety years there is still no conclusiveuniue interpretation of those formulas which means we still don t know the inmost force which binds the world and guides its course I find this rather weird and honestly a bit unsettling So much of our current technology depends on results of uantum research but we don t even know exactly how and why it worksThe acting characters in this story mostly physicists are introduced to the reader through biographical notes anecdotes uotations and so on Bohr and Born there s also another called Bohm and it s hard to tell those three apart Einstein of course and Schr dinger the cat guy Heisenberg the uncertainty guy Those I heard about before But I only had a vague picture of Everett and his many world interpretation as well as Bell and his theorem All of these and many others are introduced in detail and it s a pleasure to read about them about their struggles in search of reality or refusal to do so Given the fact that some of the people were German and Jewish and a great part of the story is set around the Nazi reign and WWII gives the book an additional historic flavor that I uite likedThe concluding chapter wraps up with some intriguing discussion about what science in general could mean for us how it should work and why it matters We are all born scientists explorers of the world we perceive around us until it s educated out of us Get some of it back and read this book why don t you This work is licensed under a Creative Commons Attribution NonCommercial ShareAlike 30 Unported License Becker explores the interpretation of uantum mechanics He and the scientists he cites all accept the functionality accuracy and mathematics of uantum mechanics but disagree on what it tells us about the world Does it merely provide information useful in making predictions for experiments and designing new technology or does it reveal an underlying reality Becker digs into Niels Bohr s Copenhagen Interpretation He discusses alternatives such as David Bohm s pilot wave interpretation Hugh Everett s many worlds interpretation the spontaneous collapse theory and decoherence Becker gives us a brief history of the development of uantum mechanics and its interpretations beginning with Bohr and Einstein and their life long debate over the meaning of uantum mechanics Particularly interesting was material about the development of alternative interpretations and how difficult it was for young physicists to challenge accepted beliefs Becker who has studied both physics and philosophy makes the case for the important role of philosophy in interpreting what all the experiments and weird results tell us about the real world Becker reviews the double slit experiment and well known thought experiments such as Schrodinger s cat in box experiment He uses these to illustrate his issues with the Copenhagen interpretation Foremost is the Measurement Problem In uantum mechanics fundamental particles are represented by a wave function which gives the probability of their being found in a particular location However the Copenhagen interpretation holds that when we measure the particle the wave function collapses and only then do we find the particle in one specific place This collapse is not supported by Schrodinger s euation which is the math establishing the wave function of uantum mechanics But it is a widely accepted postulate of many scientists who believe in the Copenhagen Interpretation What constitutes a measurement is not clear Is it when the particle is observed Observed by who or what Is it when the particle encounters a larger objectAnother important issue is that of a boundary between the uantum world and the everyday world Bohr the acknowledged father of the Copenhagen Interpretation held that there was a separation between the uantum world where particles could be found almost anywhere until measured and the normal macro world we see every day Where is that dividing line How can the particles that are the building blocks for macro objects like us behave so differently and still create the world we observe Recent experiments reveal uantum behavior in larger objects One experiment coaxed a sixty carbon atom buckyball into a uantum state where it demonstrated interference with itself ust like a photon in the double slit experiment More physicists today accept that uantum waves apply to macro objects further complicating the issues of measurement induced wave collapse and boundariesIn 1952 David Bohm building on the work of Louis of de Broglie proposed a theory of pilot waves guiding particles Both the waves and particles are always there even when no one is looking The particle surfs the wave which determines its position No need of an observer for the particle to materialize A couple of years later Hugh Everett III determined that the Copenhagen Interpretation is hopelessly incompleteexcluding in principle any deduction of classical physics from uantum theory or any adeuate investigation of the measuring processas well as a philosophic monstrosity with a reality concept for the macroscopic world and denial of the same for the microcosm He proposed that the wave function never collapsed It simply split with each outcome continuing on and splitting again ad infinitum Everett didn t discuss many worlds in his relative state theory Bryce DeWitt in a 1957 Physics Today article dubbed it the many worlds theory stoking the imagination leading to its popularization Modern concepts in cosmology such as inflation and string theory invoked the multiverse making Everett s many worlds seem less strange and by the 21st century it was second in popularity among physicists to the Copenhagen interpretationBohm Everett and others who proposed solutions that encompassed a uantum reality were derided by the physics establishment Their work was not deemed worthy of consideration by serious scientists even though Bohm and Everett were brilliant physicists As the century wore on physicists became receptive to alternative interpretations Becker recounts the frustrations of many young physicists interested in the foundations of uantum mechanics who were actively discouraged or ostracized for uestioning an accepted successful theory One inspiration was the work of John Bell Bell started his investigation of uantum mechanics after reading Bohm In a 1964 paper Bell put forth a convincing argument that nature was nonlocal a feature of Bohm s pilot wave interpretation that had been heavily criticized by the Copenhagen adherents Nonlocality means that entangled photons share a single wave function thus they synchronize their uantum states instantaneously at any distance violating special relativity Subseuent experiments have supported Bell s theorem which has been referred to as the most profound discovery of science However if the wave function splits into multiple branching worlds as Hugh Everett III proposed locality would be maintainedThe Copenhagen Interpretation holds that uantum mechanics provides useful information but does not reveal any underlying reality Until the wave function collapses there is only a mathematical probability of the location of a Particle The Particle Is Nowhere The particle is nowhere only appears when a measurement is made While this became the widely accepted view some respected physicists did not buy in These included Einstein and Schrodinger in the 1920s and 50 years later Nobel Prize winner Murray Gell Mann Gell Mann wrote The fact that an adeuate philosophical presentation of uantum physics has been so long delayed is no doubt caused by the fact that Niels Bohr brainwashed a whole generation of theorists Bohr was a charismatic figure with great influence over other top physicists His complete disdain of alternative interpretations became conventional wisdom stifling any young physicist interested in being taken seriously from pursuing alternatives The rise of cosmology in the last half of the twentieth century helped create support for those who didn t accept Bohr s views Gell Mann and James Hartle noted Measurements and observers cannot be fundamental notions in a theory that seeks to discuss the early universe when neither existed Bohr s views were likely influenced by the trending philosophy in Weimar Germany Logical Positivism developed by the Vienna Circle built on the work of physicist and philosopher Ernst Mach The positivists believed that anything not observable was meaningless Applied to the uantum this means imputing the existence of particles prior to observation is meaningless Mach was Wolfgang Pauli s godfather Pauli a preeminent physicist born and raised in Vienna was an influential supporter of positivism and Bohr Bohr stated flatly There is no uantum world Isolated material particles are abstractions This begs the uestion where do particles come from when an observation is made Reacting to such views Einstein noted What I dislike in this kind of argumentation is the basic positivistic attitude which seems to me to come to the same thing as Irish philosopher George Berkeley s principle esse est percipi to be is to be perceived Einstein believed there was a real uantum world that existed when not observed He believed uantum mechanics was an incomplete theoryOne may ask why different interpretations of the same mathematics matter Regardless of interpretation the math delivers the same results Schrodinger s euation still applies whether interpreted as Copenhagen or many worlds Becker offers a good example In the sixteenth century Tycho Brahe proposed that the sun and moon rotated around the earth and the other planets around the sun Copernicus had earth rotating around the sun too At the time both models gave the same predictions of the planets motions So why care which was right Obviously only the Copernicus model led to a better understanding and fruitful researchThe disparity in interpretation reflects that between physicists and philosophers One hundred years ago scientific curricula included course work in philosophy Einstein studied Mach and Bohr studied Kant Few physicists today get training in philosophy changing their approach to interpretation Many scientists associate philosophy with Continental philosophers who are suspicious of scientific claims However Becker points out that philosophers of physics use an analytic approach that accepts science and applies logical rigor to the interpretation of its results Becker with training in both concludes Stating that the conclusions of the Copenhagen interpretation are inevitable or forced upon us by the mathematics of the theory is simply wrong It is not true that it s meaningless to talk about reality existing independently of perceptions that we must think of the world solely as the subject of our observations Solipsism and idealism are not the message of uantum physics There is something real out in the world that somehow resembles the uantum We Interpersonal Communication just don t know what that means yet And it s theob of physics to find out If you re into stuff like this you can read the full reviewuantum Ontology The Universal Wave Function vs The Pilot Schr dinger Wave Function vs the Collapsing Schr dinger Wave function as a Stab at Explaining RealityThe diversity of possible comments on this book reflects ironically the Everett paradigm of uantum ontology There are as many views of reality as there are observers Thankfully in all instances given
the depth ofdepth of of the possible interpretations the interaction of the observer state wave and that of the rest of the universe is extremely asymmetrical the universe has a great effect on the observer but the latter s effect on the universe is mercifully infinitesimally small There is no doubt that the philosophical implications. The untold story of the heretical thinkers who dared to uestion the nature of our uantum universeEvery physicist agrees uantum mechanics is among humanity's finest scientific achievements But ask what it means and the result will be a brawl For a century most physicists have followed Niels Bohr's Copenhagen int.