Everett III (1973), Hugh, and Bryce S Dewitt, Neill Graham (editors), The Many Worlds Interpretation of Quantum Mechanics, Princeton University Press 1973 Jacket: 'A novel interpretation of quantum mechanics, first proposed in brief form by Hugh Everett in 1957, forms the nucleus around which this book has developed. The volume contains Dr Everett's short paper from 1957, "'Relative State' formulation of quantum mechanics" and a far longer exposition of his interpretation entitled "The Theory of the Universal Wave Function" never before published. In addition other papers by Wheeler, DeWitt, Graham, Cooper and van Vechten provide further discussion of the same theme. Together they constitute virtually the entire world output of scholarly commentary on the Everett interpretation.' 
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Nielsen (2016), Michael A., and Isaac L Chuang, Quantum Computation and Quantum Information, Cambridge University Press 2016 Review: A rigorous, comprehensive text on quantum information is timely. The study of quantum information and computation represents a particularly direct route to understanding quantum mechanics. Unlike the traditional route to quantum mechanics via Schroedinger's equation and the hydrogen atom, the study of quantum information requires no calculus, merely a knowledge of complex numbers and matrix multiplication. In addition, quantum information processing gives direct access to the traditionally advanced topics of measurement of quantum systems and decoherence.' Seth Lloyd, Department of Quantum Mechanical Engineering, MIT, Nature 6876: vol 416 page 19, 7 March 2002. 
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Piketty (2022), Thomas, A Brief History of Equality, Harvard UP 2022 ' The world's leading economist of inequality presents a short but sweeping and surprisingly optimistic history of human progress toward equality despite crises, disasters, and backsliding. A perfect introduction to the ideas developed in his monumental earlier books.It's easy to be pessimistic about inequality. We know it has increased dramatically in many parts of the world over the past two generations.' 
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Albert Einstein (1915), The Field Equations of Gravitation, ' In two recently published papers I have shown how to obtain field equations of gravitation that comply with the postulate of general relativity, i.e., which in their general formulation are covariant under arbitrary substitutions of space-time variables. [. . .] With this, we have finally completed the general theory of relativity as a logical structure. The postulate of relativity in its most general formulation (which makes space-time coordinates into physically meaningless parameters) leads with compelling necessity to a very specific theory of gravitation that also explains the movement of the perihelion of Mercury. However, the postulate of general relativity cannot reveal to us anything new and different about the essence of the various processes in nature than what the special theory of relativity taught us already. The opinions I recently voiced here in this regard have been in error. Every physical theory that complies with the special theory of relativity can, by means of the absolute differential calculus, be integrated into the system of general relativity theory — without the latter providing any criteria about the admissibility of such physical theory' back

Amudalat Ajasa (2)25_07_18), EPA eliminates its scientific research arm, ' The Environmental Protection Agency said on Friday it was dismantling its scientific research branch, expanding the Trump administration’s efforts to shrink the agency. The move to eliminate the Office of Research and Development, which will prompt the exodus of hundreds of chemists and scientists assigned to conduct independent research on a range of environmental hazards, is part of a push to cut 23 percent of the agency’s staff. Its work, which often underpinned stricter federal regulations, was criticized by chemical manufacturers and other industries. Ask your climate questions. With the help of generative Al, we'll try to deliver answers based on our published reporting. In January, according to an EPA press release, the agency had 16,155 employees. More than 3,700 employees have left the agency since then because of layoffs, separations and retirements, the agency said. The reductions will save taxpayers $748.8 million, the statement added. [... ] “EPA has the resources needed to accomplish the agency’s core mission of protecting human health and the environment, fulfill all statutory obligations, and support President Trump’s agenda,” the spokeswoman said in an email. [. . .] “Without the Office of Research and Development, our nation’s air, water and land will turn more toxic and our people more sick with preventable disease,” said Nicole Cantello, a legislative and political coordinator in the American Federation of Government Employees (AFGE) Council 238, a nationwide union that represents more than 8,000 EPA employees.' back

Ananyo Bhattacharya, The breakthrough proof bringing mathematics closer to a grand unified theory, ' Proving the geometric Langlands conjecture has long been considered one of the deepest and most enigmatic pursuits in modern mathematics. Ultimately, it took a team of nine mathematicians to crack the problem, in a series of five papers spanning almost 1,000 pages1–5. The group was led by Dennis Gaitsgory at the Max Planck Institute for Mathematics in Bonn, Germany, and Sam Raskin at Yale University in New Haven, Connecticut, who completed his PhD with Gaitsgory in 2014. [. . .] The Langlands programme traces its origins back 60 years, to the work of a young Canadian mathematician named Robert Langlands, who set out his vision in a handwritten letter to the leading mathematician André Weil. Over the decades, the programme attracted increasing attention from mathematicians, who marvelled at how all-encompassing it was. It was that feature that led Edward Frenkel at the University of California, Berkeley, who has made key contributions to the geometric side, to call it the grand unified theory of mathematics. Langlands’ aim was to connect two very separate major branches of mathematics — number theory (the study of integers) and harmonic analysis (the study of how complicated signals or functions break down into simple waves). A special case of the Langlands programme is the epic proof that Andrew Wiles published, in 1995, of Fermat’s last theorem — that no three positive integers a, b and c satisfy the equation an + bn = cn if n is an integer greater than 2. back

Aquinas, Summa II, I, First Part of the Second Part, ' Since, as Damascene states (De Fide Orthod. ii. 12), man is said to be made to God's image, in so far as the image implies an intelligent being endowed with free-will and self-movement: now that we have treated of the exemplar, i.e., God, and of those things which came forth from the power of God in accordance with His will; it remains for us to treat of His image, i.e., man, inasmuch as he too is the principle of his actions, as having free-will and control of his actions.Since, as Damascene states (De Fide Orthod. ii. 12), man is said to be made to God's image, in so far as the image implies an intelligent being endowed with free-will and self-movement: now that we have treated of the exemplar, i.e., God, and of those things which came forth from the power of God in accordance with His will; it remains for us to treat of His image, i.e., man, inasmuch as he too is the principle of his actions, as having free-will and control of his actions. back

Asymptotic freedom - Wikipedia, Asymptotic freedom - Wikipedia, the free encyclopedia, 'In physics, asymptotic freedom is the property of some gauge theories in which the interaction between the particles, such as quarks, becomes arbitrarily weak at ever shorter distances, i.e. length scales that asymptotically converge to zero (or, equivalently, energy scales that become arbitrarily large). Asymptotic freedom implies that in high-energy scattering the quarks move within nucleons, such as the neutron and proton, mostly as free non-interacting particles. It allows physicists to calculate the cross sections of various events in particle physics reliably using parton techniques.' back

Calculus of variations - Wikipedia, Calculus of variations - Wikipedia, the free encylopedia, ' The calculus of variations may be said to begin with Newton's minimal resistance problem in 1687, followed by the brachistochrone curve problem raised by Johann Bernoulli (1696). It immediately occupied the attention of Jakob Bernoulli and the Marquis de l'Hôpital, but Leonhard Euler first elaborated the subject, beginning in 1733. Lagrange was influenced by Euler's work to contribute significantly to the theory. After Euler saw the 1755 work of the 19-year-old Lagrange, Euler dropped his own partly geometric approach in favor of Lagrange's purely analytic approach and renamed the subject the calculus of variations in his 1756 lecture Elementa Calculi Variationum.' back

CERN, Future Circular Collider (FCC), ' The Future Circular Collider (FCC) study is developing designs for higher performance particle colliders that could follow on from the Large Hadron Collider (LHC) once it reaches the end of its High-Luminosity phase. The FCC Feasibility Study, which delivered its report on 31 March 2025, investigated the technical and financial viability of the FCC at CERN. The study looked at geological and environmental conditions, as well as technically feasible concepts for infrastructures, civil engineering and detectors. It also outlined R&D requirements concerning the efficiency and sustainability of the proposed colliders.' back

Color confinement - Wikipedia, Color confinement - Wikipedia, the free encyclopedia, ' Quarks and gluons must clump together to form hadrons. The two main typeColour s of hadron are the mesons (one quark, one antiquark) and the baryons (three quarks). In addition, colorless glueballs formed only of gluons are also consistent with confinement, though difficult to identify experimentally. Quarks and gluons cannot be separated from their parent hadron without producing new hadrons.' back

Denis Mihailov (2025_07_18), There Remains a Way to Make Russia Pay for Its Crimes, ' I personally know dozens of Russians — former political prisoners, activists and victims of police violence — whose cases were ruled on in Strasbourg, with Russia found guilty. These individuals have not had their names cleared, received compensation for their suffering, nor received official recognition of the injustice they endured. Russia has not only refused to implement these decisions but has also blocked any domestic path to legal rehabilitation. A path to achieving justice would be to funnel frozen Russian assets held abroad into a compensation fund from which victims can receive the restitution the ECHR says they are owed. Kremlin officials have already threatened a “severe” response if these assets are seized, which shows that the Kremlin views them as sufficiently important that they could be used to put pressure on the leadership. Compelling Russia to implement ECHR rulings is not about vengeance. It is about restoring justice, protecting the international legal order, and sending a clear message: authoritarian states cannot violate human rights with impunity. Russia remains a formal party to many international treaties, from the UN Charter to the International Convention on the Elimination of All Forms of Racial Discrimination. However, in recent years, it has deliberately stopped complying with these norms.' back

Eigenvalue algorithm - Wikipedia, Eigenvalue algorithm - Wikipedia, the free encyclopedia, ' In numerical analysis, one of the most important problems is designing efficient and stable algorithms for finding the eigenvalues of a matrix. These eigenvalue algorithms may also find eigenvectors.' back

Elementary particle - Wikipedia, Elementary particle - Wikipedia, the free encyclopedia, ' In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. Particles currently thought to be elementary include the fundamental fermions (quarks, leptons, antiquarks, and antileptons), which generally are "matter particles" and "antimatter particles", as well as the fundamental bosons (gauge bosons and the Higgs boson), which generally are "force particles" that mediate interactions among fermions. A particle containing two or more elementary particles is a composite particle.' back

Form of the Good - Wikipedia, Form of the Good - Wikipedia, the free encyclopedia, ' "Form of the Good", or more literally "the idea of the good" (ἡ τοῦ ἀγαθοῦ ἰδέα) is a concept in the philosophy of Plato. It is described in Plato's dialogue the Republic (508e2–3), speaking through the character of Socrates. This form is the one that allows a philosopher-in-training to advance to a philosopher-king. It cannot be clearly seen or explained, but it is the form that allows one to realize all the other forms. The definition of the Good is a perfect, eternal, and changeless Form, existing outside space and time, in which particular good things share.' back

General Covariance - Wikipedia, General covariance - Wikipedia, the free encyclopedia, In theoretical physics, general covariance (also known as diffeomorphism covariance or general invariance) is the invariance of the form of physical laws under arbitrary differentiable coordinate transformations. The essential idea is that coordinates do not exist a priori in nature, but are only artifices used in describing nature, and hence should play no role in the formulation of fundamental physical laws.' back

Hylomorphism - Wikipedia, Hylomorphism - Wikipedia, the free encyclopedia, 'Hylomorphism (Greek ὑλο- hylo-, "wood, matter" + -morphism < Greek μορφή, morphē, "form") is a philosophical theory developed by Aristotle, which analyzes substance into matter and form. Substances are conceived of as compounds of form and matter.' back

Jenna Ahrt (2025_07_08), Symbolic ‘science fair’ showcases research cut by Trump team, ' A few dozen scientists protested against the cancelling of their research grants by the US government at a ‘science fair’ staged yesterday in Washington DC. The event, organized by Democrats on a US House of Representatives science committee, is the latest to oppose actions taken by the administration of Republican President Donald Trump to slash US science spending. Researchers presented posters on how their terminated projects might have benefited society. [. . .] Since Trump took office in January, the US National Institutes of Health, the world’s largest biomedical-science funder, has terminated about 2,900 research grants, according to the database Grant Watch — although about 900 of these might be reinstated after a federal judge ruled that they were cancelled without proper justification. The US National Science Foundation (NSF), another US funding powerhouse, has cancelled more than 1,600 grants. The cuts have targeted research programmes disfavoured by the Trump team, including those investigating the health of gender minorities, the biology underlying COVID-19 and the spread of misinformation. They have also been aimed at some universities, such as Harvard, in Cambridge, Massachusetts, that the administration says have not shielded their students from antisemitism.' back

Kinda Alsamara, Eleanor Gordon & Elliot Dolan-Ens (2025_07_14), Women played key roles in Syria’s revolution. Now they’ve been pushed to the margins, ' The end of the oppressive Assad regime in Syria in late 2024 has been broadly welcomed on the global stage – underscored by the fact the United States and European Union have now lifted sanctions against the country. However, women have been marginalised by Syria’s new leadership. That’s a problem for Syrian women, of course, but it also puts at risk prospects for sustainable peace in Syria. A growing body of research, including our own, shows a direct correlation between gender equality and peace. [. . .] Copy link Email X (Twitter) Bluesky Facebook LinkedIn WhatsApp Print The end of the oppressive Assad regime in Syria in late 2024 has been broadly welcomed on the global stage – underscored by the fact the United States and European Union have now lifted sanctions against the country. However, women have been marginalised by Syria’s new leadership. That’s a problem for Syrian women, of course, but it also puts at risk prospects for sustainable peace in Syria. A growing body of research, including our own, shows a direct correlation between gender equality and peace. Syria now stands at a crossroads. Will it ensure women’s meaningful participation and follow a path to peace? Or will things head in the other direction? This is more urgent than ever. Failure to grapple with women’s rights in Syria risks plunging the nation further into extremist violence. Women excluded both before and after Assad’s rule After decades in power, the harsh Assad regime was overthrown late last year by rebels led by Sunni Islamist militant group Hayat Tahrir al-Sham. But women – who were marginalised politically and economically under Assad – continue to be systematically excluded from decision-making in the new government. This is even though women played an essential role in the Syrian revolution. They organised protests and advocated for rights (often at great personal risk). They endured sacrifices such as imprisonment, torture, disappearance and displacement. Yet, only one woman was appointed to Syria’s immediate post-Assad caretaker government. She didn’t get a ministerial title. The caretaker government spokesman reportedly suggested women’s “biological and physiological nature” makes them unsuitable for certain government roles. Reports allege the man initially appointed as Syria’s new minister of justice previously oversaw executions of women accused of being sex workers. [. . .] With the recent lifting of sanctions by the US and EU, and ongoing regional instability globally, Syria stands at a crossroads. The G7 Summit in May 2025 emphasised the global community’s renewed focus on women’s participation in peace processes. Influential middle-power countries can play a key role by reviewing sanctions and tying humanitarian aid to the promotion of human rights, gender inclusion and pluralistic governance.' back

LHCb Collaboration, Observation of charge–parity symmetry breaking in baryon decays, ' The Standard Model of particle physics—the theory of particles and interactions at the smallest scale—predicts that matter and antimatter interact differently due to violation of the combined symmetry of charge conjugation (C) and parity (P). Charge conjugation transforms particles into their antimatter particles, whereas the parity transformation inverts spatial coordinates. This prediction applies to both mesons, which consist of a quark and an antiquark, and baryons, which are composed of three quarks. However, despite having been discovered in various meson decays, CP violation has yet to be observed in baryons, the type of matter that makes up the observable Universe. Here we report a study of the decay of the beauty baryon Lambda b o to the pK−π+π− final state, which proceeds through b → u or b → s quark-level transitions, and its CP-conjugated process, using data collected by the Large Hadron Collider beauty experiment1 at the European Organization for Nuclear Research (CERN). The results reveal significant asymmetries between the decay rates of the baryon and its CP-conjugated antibaryon, providing, to our knowledge, the first observation of CP violation in baryon decays and demonstrating the different behaviours of baryons and antibaryons. In the Standard Model, CP violation arises from the Cabibbo–Kobayashi–Maskawa mechanism2, and new forces or particles beyond the Standard Model could provide further contributions. This discovery opens a new path in the search for physics beyond the Standard Model. back

Ling Xin (2025_07_09), China’s Chang’e-6 findings reveal asteroid strike may have altered moon’s far-side mantle, ' China’s Chang’e-6 lunar mission has yielded groundbreaking findings about the moon’s hidden history, revealing evidence that a colossal asteroid strike more than 4 billion years ago could have fundamentally altered the deep interior of its far side. The research was published as four open-access papers on Wednesday in Nature, one of the world’s oldest and most prestigious scientific journals, which is headquartered in London. While these papers are available to all readers regardless of subscriber status, Chinese teams are reporting a wave of scientific findings from the country’s lunar programme that American government scientists may be locked out of because of a US decision to cancel subscriptions to Nature and other Springer Nature journals. Officials cited budget concerns and dismissed the journals as “junk science”, which could hinder government scientists – including key Nasa researchers – from having access to major discoveries.' back

Louis de Broglie (1929), Nobel Lecture: The Wave Nature of the Electron, ' The necessity of assuming for light two contradictory theories-that of waves and that of corpuscles - and the inability to understand why, among the infinity of motions which an electron ought to be able to have in the atom according to classical concepts, only certain ones were possible: such were the enigmas confronting physicists at the time I resumed my studies of theoretical physics. Now a purely corpuscular theory does not contain any element permitting the definition of frequency. This also renders it necessary in the case of light to introduce simultaneously the corpuscle concept and the concept of periodicity. On the other hand the determination of the stable motions of the electrons in the atom involves whole numbers, and so far the only phenomena in which whole numbers were involved in physics were those of interference and of eigenvibrations. That suggested the idea to me that electrons themselves could not be represented as simple corpuscles either, but that a periodicity had also to be assigned to them too. . . . Thus to describe the properties of matter as well as those of light, waves and corpuscles have to be referred to at one and the same time. The electron can no longer be conceived as a single, small granule of electricity; it must be associated with a wave and this wave is no myth; its wavelength can be measured and its interferences predicted. It has thus been possible to predict a whole group of phenomena without their actually having been discovered. And it is on this concept of the duality of waves and corpuscles in Nature, expressed in a more or less abstract form, that the whole recent development of theoretical physics has been founded and that all future development of this science will apparently have to be founded.' back

Matrix mechanics - Wikipedia, Matrix mechanics - Wikipedia, the free encyclopedia, 'Matrix mechanics is a formulation of quantum mechanics created by Werner Heisenberg, Max Born, and Pascual Jordan in 1925. Matrix mechanics was the first conceptually autonomous and logically consistent formulation of quantum mechanics. It extended the Bohr Model by describing how the quantum jumps occur. It did so by interpreting the physical properties of particles as matrices that evolve in time. It is equivalent to the Schrödinger wave formulation of quantum mechanics, and is the basis of Dirac's bra-ket notation for the wave function. back

Ranjana Srivastava (2025_07_16), New research shows a blindingly simple new procedure can help save children’s lives in emergency departments, An eight-year-old child attends her last day of school before Easter holidays, plays with her siblings, has dinner and gets ice-cream. The next day she develops a headache and vomiting. Then, as her hands grow cold, her parents take her to the local children’s hospital. Minutes after the child is triaged as lower priority, her mother tells the emergency department clerk that she is concerned about white patches in her daughter’s eyes. A junior doctor decides this can wait. One minute later, the child’s mother is back at the desk. This time, a nurse documents a high temperature and heart rate but doesn’t act. An hour later, the child can barely speak. A nurse acts. Two hours later, the child is dead. [. . .] Recently a group of Australian researchers has designed a pragmatic study to examine the relationship between parental concern for clinical deterioration and critical illness. Over a period of two years, across nearly 74,000 children younger than 19 presenting to a paediatric emergency department or inpatient unit, parents were asked one simple question: “Are you worried your child is getting worse?” [. . .] The second sobering finding was that compared with patients whose parents did not have a documented concern, patients whose parents reported a concern were more likely to be admitted to intensive care, receive mechanical ventilation and die during admission. As if this were not lesson enough, parental concern was found to be more strongly associated with ICU admission than any abnormal vital sign including abnormal heart rate or breathing, cardinal signs of deterioration relied upon by clinicians. In 19% of cases, parents reported a problem several hours before any vital sign abnormality. I had to read this multiple times to absorb the significance. It’s all very well to have bright rooms and fancy equipment but what is the most child-friendly thing of all? It’s to ask the parents if they are worried. If the findings can be replicated, this “intervention” will turn out to be blindingly simple and yet, potentially life-saving. This is the stuff of good medicine – cheap, effective, widely applicable.' back

Rhiannon Lucy Cosslett (2025_04_13), Ireland’s mother-and-baby homes are a stain on the Catholic church – but this latest refusal to atone is a new low, ' There are some stories so horrifying that their details embed themselves in your flesh and haunt you for the rest of your days. The suffering of the women and babies – an estimated 170,000 of them – who were incarcerated and abused in the Magdalene laundries and mother-and-baby homes that housed “fallen women” is one such story. It is a scandal that is difficult to read about without experiencing an overwhelming feeling of disgust, from the testimonies of abuse and forced adoption, to the mass grave at the former St Mary’s mother-and-baby home near Tuam, County Galway, which contained 796 bodies of babies and children. The nuns put many of them in a septic tank. There were no burial records. [. . .] Nothing from the nuns, or the Catholic church, has really come close to expressing true remorse. A “definitive” apology in 2021 from Eamon Martin, Ireland’s most senior church figure, was worded thus: “I accept that the church was clearly part of that culture in which people were frequently stigmatised, judged and rejected. For that, and for the longlasting hurt and emotional distress that has resulted, I unreservedly apologise.” Yet the church wasn’t just part of that culture. It was the culture, saturating every aspect of life in Ireland, shaping public attitudes towards women and their babies, encouraging their shaming and ostracising. Some campaigners have called for church assets to be seized unless the institution contributes to a state-run redress scheme.' [' ' ' ] The treatment of children born out of wedlock in Ireland as “an inferior subspecies” – then taoiseach Enda Kenny’s words in 2014 – and the humiliation to which they were subjected is a stain on the church’s history. Corless said in interview at the time that she had lost respect for the Catholic church. She is by no means alone in that.' back

Richard McGregor (2025_07_17, There’s no free lunch with Xi, as Trump will surely remind Albanese, ' For once, though, it wasn’t Trump who was disrupting a comfortable narrative of an Australian leader confidently rebuilding ties with China without first having broken bread with a new White House in Washington. The skunk at Albanese’s party was Trump’s top policy official in the Pentagon, Elbridge Colby, with demands that Australia commit to joint war planning over Taiwan as part of the AUKUS deal to buy US nuclear-powered submarines. [. . .] China is putting on its best face for Albanese, but it is no less ruthless and is not restrained by the decades-long political kinship that Australia enjoys with the US. Xi and the Chinese system have invested personally in Albanese this week. For them, this trip is about much more than trade, as evidenced by Xi’s invitation to lunch on Wednesday. A banquet it may have been, but to borrow a phrase, there is no such thing as a free lunch in Beijing. If Albanese needs any reminding, he will surely get it when he eventually does make it to the White House and meets Trump face to face.' back

Richard P. Feynman (1985), Quantum mechanical computers, ' We are here considering ideal machines; the effects of imperfections will be considered later. This study is one of principle; our aim is to exhibit some Hamiltonian for a system which could serve as a computer. We are not concerned with whether we have the most efficient system, nor how we could best implement it.' back

Schrödinger equation - Wikipedia, Schrödinger equation - Wikipedia, the free encyclopedia, ' In quantum mechanics, the Schrödinger equation is a partial differential equation that describes how the quantum state of a quantum system changes with time. It was formulated in late 1925, and published in 1926, by the Austrian physicist Erwin Schrödinger. . . . In classical mechanics Newton's second law, (F = ma), is used to mathematically predict what a given system will do at any time after a known initial condition. In quantum mechanics, the analogue of Newton's law is Schrödinger's equation for a quantum system (usually atoms, molecules, and subatomic particles whether free, bound, or localized). It is not a simple algebraic equation, but in general a linear partial differential equation, describing the time-evolution of the system's wave function (also called a "state function").' back

Small Things Like These (film) - Wikipedia, Small Things Like These (film) - Wikipedia, the free encyclopedia, ' Small Things like These is a 2024 historical drama film directed by Tim Mielants and adapted by Enda Walsh from the 2021 novel by Claire Keegan. It stars Cillian Murphy (who also serves as a producer), Eileen Walsh, Michelle Fairley, Emily Watson, Clare Dunne, and Helen Behan. An international co-production between Ireland and Belgium, its plot focuses on the infamous Magdalene laundries in Ireland. Small Things like These had its world premiere at the 74th Berlin International Film Festival on 15 February 2024, and was released in Ireland and the United Kingdom on 1 November 2024. It received positive reviews from critics.' back

Wojciech Hubert Zurek (2008), Quantum origin of quantum jumps: breaking of unitary symmetry induced by information transfer and the transition from quantum to classical, 'Submitted on 17 Mar 2007 (v1), last revised 18 Mar 2008 (this version, v3)) Measurements transfer information about a system to the apparatus, and then further on – to observers and (often inadvertently) to the environment. I show that even imperfect copying essential in such situations restricts possible unperturbed outcomes to an orthogonal subset of all possible states of the system, thus breaking the unitary symmetry of its Hilbert space implied by the quantum superposition principle. Preferred outcome states emerge as a result. They provide framework for the “wavepacket collapse”, designating terminal points of quantum jumps, and defining the measured observable by specifying its eigenstates.' back