THE CENTER FOR PAN ISLAMIC SCIENCE & TECHNICAL RESEARCH(CPISTR)
In the name of Allah, the Most Gracious, the Most Merciful.
P.S: Sadarghat,West Madarbari
BANGLADESH
P.S: Sadarghat,West Madarbari
BANGLADESH
Cosmology
(Courtesy of Wikipedia, Encyclopedia)
The Hubble extreme Deep Field (XDF) was completed in September 2012 and shows the farthest galaxies ever photographed. Except for the few stars in the foreground (which are bright and easily recognizable because only they have diffraction spikes), every speck of light in the photo is an individual galaxy, some of them as old as 13.2 billion years; the observable universe is estimated to contain more than 2 trillion galaxies.[1]
Cosmology (from the Greek κόσμος, kosmos "world" and -λογία, -logia "study of") is a branch of astronomy concerned with the studies of the origin and evolution of the universe, from the Big Bang to today and on into the future. It is the scientific study of the origin, evolution, and eventual fate of the universe. Physical cosmology is the scientific study of the universe's origin, its large-scale structures and dynamics, and its ultimate fate, as well as the laws of science that govern these areas.[2]
The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia,[3] and in 1731 taken up in Latin by German philosopher Christian Wolff, in Cosmologia Generalis.[4]
Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions of creation myths and eschatology.
Physical cosmology is studied by scientists, such as astronomers and physicists, as well as philosophers, such as metaphysicians, philosophers of physics, and philosophers of space and time. Because of this shared scope with philosophy, theories in physical cosmology may include both scientific and non-scientific propositions, and may depend upon assumptions that cannot be tested. Cosmology differs from astronomy in that the former is concerned with the Universe as a whole while the latter deals with individual celestial objects. Modern physical cosmology is dominated by the Big Bang theory, which attempts to bring together observational astronomy and particle physics;[5][6] more specifically, a standard parameterization of the Big Bang with dark matter and dark energy, known as the Lambda-CDM model.
Theoretical astrophysicist David N. Spergel has described cosmology as a "historical science" because "when we look out in space, we look back in time" due to the finite nature of the speed of light.[7]
Big Bang
bɪɡ ˈbaŋ/
noun
1. 1.
ASTRONOMY
the rapid expansion of matter from a state of extremely high density and temperature which according to current cosmological theories marked the origin of the universe.
Big Bang
Courtesy of Wikipedia, the Encyclopedia)
"Big Bang theory" redirects here. For the American TV sitcom, see The Big Bang Theory. For other uses, see Big Bang (disambiguation) and Big Bang Theory (disambiguation).
Timeline of the metric expansion of space, where space (including hypothetical non-observable portions of the universe) is represented at each time by the circular sections. On the left, the dramatic expansion occurs in the inflationary epoch; and at the center, the expansion accelerates (artist's concept; not to scale).
The Big Bang theory is the prevailing cosmological model for the universe[1] from the earliest known periodsthrough its subsequent large-scale evolution.[2][3][4] The model describes how the universe expanded from a very high-density and high-temperature state,[5][6] and offers a comprehensive explanation for a broad range of phenomena, including the abundance of light elements, the cosmic microwave background (CMB), large scale structure and Hubble's law.[7] If the known laws of physics are extrapolated to the highest density regime, the result is a singularity which is typically associated with the Big Bang. Physicists are undecided whether this means the universe began from a singularity, or that current knowledge is insufficient to describe the universe at that time. Detailed measurements of the expansion rate of the universe place the Big Bang at around 13.8 billion years ago, which is thus considered the age of the universe.[8] After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, and later simple atoms. Giant clouds of these primordial elements later coalesced through gravity in halos of dark matter, eventually forming the stars and galaxies visible today.
Since Georges Lemaître first noted in 1927 that an expanding universe could be traced back in time to an originating single point, scientists have built on his idea of cosmic expansion. The scientific community was once divided between supporters of two different theories, the Big Bang and the Steady State theory, but a wide range of empirical evidence has strongly favored the Big Bang which is now universally accepted.[9] In 1929, from analysis of galactic redshifts, Edwin Hubble concluded that galaxies are drifting apart; this is important observational evidence consistent with the hypothesis of an expanding universe. In 1964, the cosmic microwave background radiation was discovered, which was crucial evidence in favor of the Big Bang model,[10] since that theory predicted the existence of background radiation throughout the universe before it was discovered. More recently, measurements of the redshifts of supernovae indicate that the expansion of the universe is accelerating, an observation attributed to dark energy's existence.[11]The known physical laws of nature can be used to calculate the characteristics of the universe in detail back in time to an initial state of extreme density and temperature.[12]
In physics, special relativity (also known as the special theory of relativity) is the generally accepted and experimentally confirmed physical theory regarding the relationship between space and time. In Albert Einstein's original pedagogical treatment, it is based on two postulates:
1. the laws of physics are invariant (i.e. identical) in all inertial frames of reference (i.e. non-accelerating frames of reference); and
2. the speed of light in a vacuum is the same for all observers, regardless of the motion of the light source or observer.
Some of the work of Albert Einstein in special relativity is built on the earlier work by Hendrik Lorentz.
Special relativity was originally proposed by Albert Einstein in a paper published on 26 September 1905 titled "On the Electrodynamics of Moving Bodies".[p 1] The inconsistency of Newtonian mechanics with Maxwell's equations of electromagnetism and, experimentally, the Michelson-Morley null result (and subsequent similar experiments) demonstrated that the historically hypothesized luminiferous aether did not exist. This led to Einstein's development of special relativity, which corrects mechanics to handle situations involving all motions and especially those at a speed close to that of light (known as relativistic velocities). Today, special relativity is proven to be the most accurate model of motion at any speed when gravitational effects are negligible. Even so, the Newtonian model is still valid as a simple and accurate approximation at low velocities (relative to the speed of light), for example, the everyday motions on Earth.
Special relativity has a wide range of consequences. These have been experimentally verified,[1] and include length contraction, time dilation, relativistic mass, mass–energy equivalence, a universal speed limit, the speed of causality and relativity of simultaneity. It has, for example, replaced the conventional notion of an absolute universal time with the notion of a time that is dependent on reference frame and spatial position. Rather than an invariant time interval between two events, there is an invariant spacetime interval. Combined with other laws of physics, the two postulates of special relativity predict the equivalence of mass and energy, as expressed in the mass–energy equivalence formula E = mc2 (c is the speed of light in a vacuum).[2][3]
A defining feature of special relativity is the replacement of the Galilean transformations of Newtonian mechanics with the Lorentz transformations. Time and space cannot be defined separately from each other (as was earlier thought to be the case). Rather, space and time are interwoven into a single continuum known as "spacetime". Events that occur at the same time for one observer can occur at different times for another.
Until Einstein developed general relativity, introducing a curved spacetime to incorporate gravity, the phrase "special relativity" was not used. A translation sometimes used is "restricted relativity"; "special" really means "special case".[p 2][p 3][p 4][note 1]
The theory is "special" in that it only applies in the special case where the space time is "flat", i.e., the curvature of spacetime, described by the energy-momentum tensor and causing gravity, is negligible.[4][note 2] In order to correctly accommodate gravity, Einstein formulated general relativity in 1915. Special relativity, contrary to some historical descriptions, does accommodate accelerations as well as accelerating frames of reference.[5][6]
Just as Galilean relativity is now accepted to be an approximation of special relativity that is valid for low speeds, special relativity is considered an approximation of general relativity that is valid for weak gravitational fields, i.e. at a sufficiently small scale (for example, for tidal forces) and in conditions of free fall. General relativity, however, incorporates noneuclidean geometry in order to represent gravitational effects as the geometric curvature of spacetime. Special relativity is restricted to the flat spacetime known as Minkowski space. As long as the universe can be modeled as a pseudo-Riemannian manifold, a Lorentz-invariant frame that abides by special relativity can be defined for a sufficiently small neighborhood of each point in this curved spacetime.
Galileo Galilei had already postulated that there is no absolute and well-defined state of rest (no privileged reference frames), a principle now called Galileo's principle of relativity. Einstein extended this principle so that it accounted for the constant speed of light,[7] a phenomenon that had been observed in the Michelson–Morley experiment. He also postulated that it holds for all the laws of physics, including both the laws of mechanics and of electrodynamics.[8]
Higgs boson
Courtesy of Wikipedia, the Encyclopedia
Physicists explain the properties of forces between elementary particles in terms of the Standard Model – a widely accepted framework for understanding almost everything in physics in the known universe, other than gravity. (A separate theory, general relativity, is used for gravity.) In this model, the fundamental forces in nature arise from properties of our universe called gauge invariance and symmetries. The forces are transmitted by particles known as gauge bosons.[13][14]
In the Standard Model, the Higgs particle is a boson with spin zero, no electric charge and no colour charge. It is also very unstable, decaying into other particles almost immediately. The Higgs field is a scalar field, with two neutral and two electrically charged components that form a complex doublet of the weak isospin SU(2) symmetry. The Higgs field has a "Mexican hat-shaped" potential. In its ground state, this causes the field to have a nonzero value everywhere (including otherwise empty space), and as a result, below a very high energy it breaks the weak isospin symmetry of the electroweak interaction. (Technically the non-zero expectation value converts the Lagrangian's Yukawa coupling terms into mass terms.) When this happens, three components of the Higgs field are "absorbed" by the SU(2) and U(1) gauge bosons (the "Higgs mechanism") to become the longitudinal components of the now-massive W and Z bosons of the weak force. The remaining electrically neutral component either manifests as a Higgs particle, or may couple separately to other particles known as fermions (via Yukawa couplings), causing these to acquire mass as well.[15]
History
Particle physicists study matter made from fundamental particles whose interactions are mediated by exchange particles – gauge bosons – acting as force carriers. At the beginning of the 1960s a number of these particles had been discovered or proposed, along with theories suggesting how they relate to each other, some of which had already been reformulated as field theories in which the objects of study are not particles and forces, but quantum fields and their symmetries.[51]:150 However, attempts to produce quantum field models for two of the four known fundamental forces – the electromagnetic force and the weak nuclear force – and then to unify these interactions, were still unsuccessful.
One known problem was that gauge invariant approaches, including non-abelian models such as Yang–Mills theory(1954), which held great promise for unified theories, also seemed to predict known massive particles as massless.[52] Goldstone's theorem, relating to continuous symmetries within some theories, also appeared to rule out many obvious solutions,[53] since it appeared to show that zero-mass particles also would have to exist that simply were "not seen".[54] According to Guralnik, physicists had "no understanding" how these problems could be overcome.[54]
Particle physicist and mathematician Peter Woit summarised the state of research at the time:
Yang and Mills work on non-abelian gauge theory had one huge problem: in perturbation theory it has massless particles which don’t correspond to anything we see. One way of getting rid of this problem is now fairly well understood, the phenomenon of confinement realized in QCD, where the strong interactions get rid of the massless “gluon” states at long distances. By the very early sixties, people had begun to understand another source of massless particles: spontaneous symmetry breaking of a continuous symmetry. What Philip Anderson realized and worked out in the summer of 1962 was that, when you have both gauge symmetry and spontaneous symmetry breaking, the Nambu–Goldstone massless mode can combine with the massless gauge field modes to produce a physical massive vector field. This is what happens in superconductivity, a subject about which Anderson was (and is) one of the leading experts.[52] [text condensed]
The Higgs mechanism is a process by which vector bosons can acquire rest mass without explicitly breaking gauge invariance, as a byproduct of spontaneous symmetry breaking.[55][56] Initially, the mathematical theory behind spontaneous symmetry breaking was conceived and published within particle physics by Yoichiro Nambu in 1960,[57] and the concept that such a mechanism could offer a possible solution for the "mass problem" was originally suggested in 1962 by Philip Anderson (who had previously written papers on broken symmetry and its outcomes in superconductivity.[58] Anderson concluded in his 1963 paper on the Yang-Mills theory, that "considering the superconducting analog... [t]hese two types of bosons seem capable of canceling each other out... leaving finite mass bosons"),[59][60] and in March 1964, Abraham Klein and Benjamin Lee showed that Goldstone's theorem could be avoided this way in at least some non-relativistic cases, and speculated it might be possible in truly relativistic cases.[61]
These approaches were quickly developed into a full relativistic model, independently and almost simultaneously, by three groups of physicists: by François Englert and Robert Brout in August 1964;[62] by Peter Higgs in October 1964;[63] and by Gerald Guralnik, Carl Hagen, and Tom Kibble (GHK) in November 1964.[64] Higgs also wrote a short, but important,[55] response published in September 1964 to an objection by Gilbert,[65] which showed that if calculating within the radiation gauge, Goldstone's theorem and Gilbert's objection would become inapplicable.[k] (Higgs later described Gilbert's objection as prompting his own paper.[66]) Properties of the model were further considered by Guralnik in 1965,[67] by Higgs in 1966,[68] by Kibble in 1967,[69] and further by GHK in 1967.[70] The original three 1964 papers demonstrated that when a gauge theory is combined with an additional field that spontaneously breaks the symmetry, the gauge bosons may consistently acquire a finite mass.[55][56][71] In 1967, Steven Weinberg [72] and Abdus Salam[73]independently showed how a Higgs mechanism could be used to break the electroweak symmetry of Sheldon Glashow's unified model for the weak and electromagnetic interactions,[74] (itself an extension of work by Schwinger), forming what became the Standard Model of particle physics. Weinberg was the first to observe that this would also provide mass terms for the fermions.[75][l]
At first, these seminal papers on spontaneous breaking of gauge symmetries were largely ignored, because it was widely believed that the (non-Abelian gauge) theories in question were a dead-end, and in particular that they could not be renormalised. In 1971–72, Martinus Veltman and Gerard 't Hooft proved renormalisation of Yang–Mills was possible in two papers covering massless, and then massive, fields.[75] Their contribution, and the work of others on the renormalisation group – including "substantial" theoretical work by Russian physicists Ludvig Faddeev, Andrei Slavnov, Efim Fradkin, and Igor Tyutin[76] – was eventually "enormously profound and influential",[77] but even with all key elements of the eventual theory published there was still almost no wider interest. For example, Coleman found in a study that "essentially no-one paid any attention" to Weinberg's paper prior to 1971[78] and discussed by David Politzer in his 2004 Nobel speech.[77] – now the most cited in particle physics [79] – and even in 1970 according to Politzer, Glashow's teaching of the weak interaction contained no mention of Weinberg's, Salam's, or Glashow's own work.[77] In practice, Politzer states, almost everyone learned of the theory due to physicist Benjamin Lee, who combined the work of Veltman and 't Hooft with insights by others, and popularised the completed theory.[77] In this way, from 1971, interest and acceptance "exploded"[77] and the ideas were quickly absorbed in the mainstream.[75][77]
The resulting electroweak theory and Standard Model have accurately predicted (among other things) weak neutral currents, three bosons, the top and charm quarks, and with great precision, the mass and other properties of some of these.[d] Many of those involved eventually won Nobel Prizes or other renowned awards. A 1974 paper and comprehensive review in Reviews of Modern Physics commented that "while no one doubted the [mathematical] correctness of these arguments, no one quite believed that nature was diabolically clever enough to take advantage of them",[80] adding that the theory had so far produced accurate answers that accorded with experiment, but it was unknown whether the theory was fundamentally correct.[81] By 1986 and again in the 1990s it became possible to write that understanding and proving the Higgs sector of the Standard Model was "the central problem today in particle physics".[18][19]
Symmetry breaking
By the early 1960s, physicists had realised that a given symmetry law might not always be followed under certain conditions, at least in some areas of physics.[c] This is called symmetry breaking and was recognised in the late 1950s by Yoichiro Nambu. Symmetry breaking can lead to surprising and unexpected results. In 1962 physicist Philip Anderson – an expert in superconductivity – wrote a paper that considered symmetry breaking in particle physics, and suggested that perhaps symmetry breaking might be the missing piece needed to solve the problems of gauge invariance in particle physics. If electroweak symmetry was somehow being broken, it might explain why electromagnetism's boson is massless, yet the weak force bosons have mass, and solve the problems. Shortly afterwards, in 1963, this was shown to be theoretically possible, at least for some limited (non-relativistic) cases.
Symmetry breaking of the electro ```weak interaction
Below an extremely high temperature, electroweak symmetry breaking causes the electroweak interaction to manifest in part as the short-ranged weak force, which is carried by massive gauge bosons. This symmetry breaking is required for atoms and other structures to form, as well as for nuclear reactions in stars, such as our Sun. The Higgs field is responsible for this symmetry breaking.
Higgs mechanism
Following the 1962 and 1963 papers, three groups of researchers independently published the 1964 PRL symmetry breaking papers with similar conclusions and for all cases, not just some limited cases. They showed that the conditions for electroweak symmetry would be "broken" if an unusual type of field existed throughout the universe, and indeed, some fundamental particles would acquire mass. The field required for this to happen (which was purely hypothetical at the time) became known as the Higgs field (after Peter Higgs, one of the researchers) and the mechanism by which it led to symmetry breaking, known as the Higgs mechanism. A key feature of the necessary field is that it would take less energy for the field to have a non-zero value than a zero value, unlike all other known fields, therefore, the Higgs field has a non-zero value (or vacuum expectation) everywhere. It was the first proposal capable of showing how the weak force gauge bosons could have mass despite their governing symmetry, within a gauge invariant theory.
Although these ideas did not gain much initial support or attention, by 1972 they had been developed into a comprehensive theory and proved capable of giving "sensible" resultsthat accurately described particles known at the time, and which, with exceptional accuracy, predicted several other particles discovered during the following years.[d] During the 1970s these theories rapidly became the Standard Model of particle physics. There was not yet any direct evidence that the Higgs field existed, but even without proof of the field, the accuracy of its predictions led scientists to believe the theory might be true. By the 1980s the question of whether or not the Higgs field existed, and therefore whether or not the entire Standard Model was correct, had come to be regarded as one of the most important unanswered questions in particle physics.
Higgs field
According to the Standard Model, a field of the necessary kind (the Higgs field) exists throughout space and breaks certain symmetry laws of the electroweak interaction.[e] Via the Higgs mechanism, this field causes the gauge bosons of the weak force to be massive at all temperatures below an extreme high value. When the weak force bosons acquire mass, this affects their range, which becomes very small.[f] Furthermore, it was later realised that the same field would also explain, in a different way, why other fundamental constituents of matter (including electrons and quarks) have mass.
For many decades, scientists had no way to determine whether or not the Higgs field existed, because the technology needed for its detection did not exist at that time. If the Higgs field did exist, then it would be unlike any other known fundamental field, but it also was possible that these key ideas, or even the entire Standard Model, were somehow incorrect.[g] Only discovering that the Higgs boson and therefore the Higgs field existed solved the problem.
Unlike other known fields such as the electromagnetic field, the Higgs field is scalar and has a non-zero constant value in vacuum. The existence of the Higgs field became the last unverified part of the Standard Model of particle physics, and for several decades was considered "the central problem in particle physics".[18][19]
The presence of the field, now confirmed by experimental investigation, explains why some fundamental particles have mass, despite the symmetries controlling their interactions implying that they should be massless. It also resolves several other long-standing puzzles, such as the reason for the extremely short range of the weak force.
Although the Higgs field is non-zero everywhere and its effects are ubiquitous, proving its existence was far from easy. In principle, it can be proved to exist by detecting its excitations, which manifest as Higgs particles (the Higgs boson), but these are extremely difficult to produce and detect. The importance of this fundamental question led to a 40-year search, and the construction of one of the world's most expensive and complex experimental facilities to date, CERN's Large Hadron Collider,[20] in an attempt to create Higgs bosons and other particles for observation and study. On 4 July 2012, the discovery of a new particle with a mass between 125 and 127 GeV/c2 was announced; physicists suspected that it was the Higgs boson.[21][22][23] Since then, the particle has been shown to behave, interact, and decay in many of the ways predicted for Higgs particles by the Standard Model, as well as having even parity and zero spin,[6][7] two fundamental attributes of a Higgs boson. This also means it is the first elementary scalar particle discovered in nature.[24] As of 2018, in-depth research shows the particle continuing to behave in line with predictions for the Standard Model Higgs boson. More studies are needed to verify with higher precision that the discovered particle has all of the properties predicted, or whether, as described by some theories, multiple Higgs bosons exist.[25]
Higgs boson
The hypothesised Higgs mechanism made several accurate predictions,[d][26]:22 however to confirm its existence there was an extensive search for a matching particleassociated with it – the "Higgs boson".[8][9] Detecting Higgs bosons was difficult due to the energy required to produce them and their very rare production even if the energy is sufficient. It was therefore several decades before the first evidence of the Higgs boson was found. Particle colliders, detectors, and computers capable of looking for Higgs bosons took more than 30 years (c. 1980–2010) to develop.
By March 2013, the existence of the Higgs boson was confirmed, and therefore, the concept of some type of Higgs field throughout space is strongly supported.[21][23][6] The nature and properties of this field are now being investigated further, using more data collected at the LHC.[1]
Particle physics
The Higgs boson validates the Standard Model through the mechanism of mass generation. As more precise measurements of its properties are made, more advanced extensions may be suggested or excluded. As experimental means to measure the field's behaviours and interactions are developed, this fundamental field may be better understood. If the Higgs field had not been discovered, the Standard Model would have needed to be modified or superseded.
Related to this, a belief generally exists among physicists that there is likely to be "new" physics beyond the Standard Model, and the Standard Model will at some point be extended or superseded. The Higgs discovery, as well as the many measured collisions occurring at the LHC, provide physicists a sensitive tool to parse data for where the Standard Model fails, and could provide considerable evidence guiding researchers into future theoretical developments
Particle mass acquisition
The Higgs field is pivotal in generating the masses of quarks and charged leptons (through Yukawa coupling) and the W and Z gauge bosons (through the Higgs mechanism).
It is worth noting that the Higgs field does not "create" mass out of nothing (which would violate the law of conservation of energy), nor is the Higgs field responsible for the mass of all particles. For example, approximately 99% of the mass of baryons (composite particles such as the proton and neutron), is due instead to quantum chromodynamic binding energy, which is the sum of the kinetic energies of quarks and the energies of the massless gluons mediating the strong interaction inside the baryons.[27] In Higgs-based theories, the property of "mass" is a manifestation of potential energy transferred to fundamental particles when they interact ("couple") with the Higgs field, which had contained that mass in the form of energy.[28]
Scalar fields and extension of the Standard Model[edit]
The Higgs field is the only scalar (spin 0) field to be detected; all the other fields in the Standard Model are spin ½ fermions or spin 1 bosons. According to Rolf-Dieter Heuer, director general of CERN when the Higgs boson was discovered, this existence proof of a scalar field is almost as important as the Higgs's role in determining the mass of other particles. It suggests that other hypothetical scalar fields suggested by other theories, from the inflaton to quintessence, could perhaps exist as well.[29][30]
Practical and technological impact
As yet, there are no known immediate technological benefits of finding the Higgs particle. However, a common pattern for fundamental discoveries is for practical applications to follow later, and once the discovery has been explored further, perhaps becoming the basis for new technologies of importance to society.[48][49][50]
The challenges in particle physics have furthered major technological progress of widespread importance. For example, the World Wide Web began as a project to improve CERN's communication system. CERN's requirement to process massive amounts of data produced by the Large Hadron Collider also led to contributions to the fields of distributed and cloud computing[citation needed].
The three papers written in 1964 were each recognised as milestone papers during Physical Review Letters's 50th anniversary celebration.[71] Their six authors were also awarded the 2010 J. J. Sakurai Prize for Theoretical Particle Physics for this work.[82] (A controversy also arose the same year, because in the event of a Nobel Prize only up to three scientists could be recognised, with six being credited for the papers.[83]) Two of the three PRL papers (by Higgs and by GHK) contained equations for the hypothetical field that eventually would become known as the Higgs field and its hypothetical quantum, the Higgs boson.[63][64] Higgs' subsequent 1966 paper showed the decay mechanism of the boson; only a massive boson can decay and the decays can prove the mechanism.[citation needed]
In the paper by Higgs the boson is massive, and in a closing sentence Higgs writes that "an essential feature" of the theory "is the prediction of incomplete multiplets of scalarand vector bosons".[63] (Frank Close comments that 1960s gauge theorists were focused on the problem of massless vector bosons, and the implied existence of a massive scalar boson was not seen as important; only Higgs directly addressed it.[84]:154, 166, 175) In the paper by GHK the boson is massless and decoupled from the massive states.[64]In reviews dated 2009 and 2011, Guralnik states that in the GHK model the boson is massless only in a lowest-order approximation, but it is not subject to any constraint and acquires mass at higher orders, and adds that the GHK paper was the only one to show that there are no massless Goldstone bosons in the model and to give a complete analysis of the general Higgs mechanism.[54][85] All three reached similar conclusions, despite their very different approaches: Higgs' paper essentially used classical techniques, Englert and Brout's involved calculating vacuum polarisation in perturbation theory around an assumed symmetry-breaking vacuum state, and GHK used operator formalism and conservation laws to explore in depth the ways in which Goldstone's theorem may be worked around.[55] Some versions of the theory predicted more than one kind of Higgs fields and bosons, and alternative "Higgsless" models were considered until the discovery of the Higgs boson.
Discovery of candidate boson at CERN
On 4 July 2012 both of the CERN experiments announced they had independently made the same discovery:[114] CMS of a previously unknown boson with mass 125.3 ± 0.6 GeV/c2[115][116] and ATLAS of a boson with mass 126.0 ± 0.6 GeV/c2.[117][118] Using the combined analysis of two interaction types (known as 'channels'), both experiments independently reached a local significance of 5 sigma – implying that the probability of getting at least as strong a result by chance alone is less than 1 in 3 million. When additional channels were taken into account, the CMS significance was reduced to 4.9 sigma.[116]On 22 June 2012 CERN announced an upcoming seminar covering tentative findings for 2012,[105][106] and shortly afterwards (from around 1 July 2012 according to an analysis of the spreading rumour in social media[107]) rumours began to spread in the media that this would include a major announcement, but it was unclear whether this would be a stronger signal or a formal discovery.[108][109] Speculation escalated to a "fevered" pitch when reports emerged that Peter Higgs, who proposed the particle, was to be attending the seminar,[110][111] and that "five leading physicists" had been invited – generally believed to signify the five living 1964 authors – with Higgs, Englert, Guralnik, Hagen attending and Kibble confirming his invitation (Brout having died in 2011).[112][113]
The two teams had been working 'blinded' from each other from around late 2011 or early 2012,[99]meaning they did not discuss their results with each other, providing additional certainty that any common finding was genuine validation of a particle.[88] This level of evidence, confirmed independently by two separate teams and experiments, meets the formal level of proof required to announce a confirmed discovery.
On 31 July 2012, the ATLAS collaboration presented additional data analysis on the "observation of a new particle", including data from a third channel, which improved the significance to 5.9 sigma (1 in 588 million chance of obtaining at least as strong evidence by random background effects alone) and mass 126.0 ± 0.4 (stat) ± 0.4 (sys) GeV/c2,[118] and CMS improved the significance to 5-sigma and mass 125.3 ± 0.4 (stat) ± 0.5 (sys) GeV/c2.[115]
The new particle tested as a possible Higgs boson
Following the 2012 discovery, it was still unconfirmed whether or not the 125 GeV/c2 particle was a Higgs boson. On one hand, observations remained consistent with the observed particle being the Standard Model Higgs boson, and the particle decayed into at least some of the predicted channels. Moreover, the production rates and branching ratios for the observed channels broadly matched the predictions by the Standard Model within the experimental uncertainties. However, the experimental uncertainties currently still left room for alternative explanations, meaning an announcement of the discovery of a Higgs boson would have been premature.[119] To allow more opportunity for data collection, the LHC's proposed 2012 shutdown and 2013–14 upgrade were postponed by 7 weeks into 2013.[120]
In November 2012, in a conference in Kyoto researchers said evidence gathered since July was falling into line with the basic Standard Model more than its alternatives, with a range of results for several interactions matching that theory's predictions.[121] Physicist Matt Strassler highlighted "considerable" evidence that the new particle is not a pseudoscalar negative parity particle (consistent with this required finding for a Higgs boson), "evaporation" or lack of increased significance for previous hints of non-Standard Model findings, expected Standard Model interactions with W and Z bosons, absence of "significant new implications" for or against supersymmetry, and in general no significant deviations to date from the results expected of a Standard Model Higgs boson.[122] However some kinds of extensions to the Standard Model would also show very similar results;[123] so commentators noted that based on other particles that are still being understood long after their discovery, it may take years to be sure, and decades to fully understand the particle that has been found.[121][122]
These findings meant that as of January 2013, scientists were very sure they had found an unknown particle of mass ~ 125 GeV/c2, and had not been misled by experimental error or a chance result. They were also sure, from initial observations, that the new particle was some kind of boson. The behaviours and properties of the particle, so far as examined since July 2012, also seemed quite close to the behaviours expected of a Higgs boson. Even so, it could still have been a Higgs boson or some other unknown boson, since future tests could show behaviours that do not match a Higgs boson, so as of December 2012 CERN still only stated that the new particle was "consistent with" the Higgs boson,[21][23] and scientists did not yet positively say it was the Higgs boson.[124] Despite this, in late 2012, widespread media reports announced (incorrectly) that a Higgs boson had been confirmed during the year.[o]
In January 2013, CERN director-general Rolf-Dieter Heuer stated that based on data analysis to date, an answer could be possible 'towards' mid-2013,[130] and the deputy chair of physics at Brookhaven National Laboratory stated in February 2013 that a "definitive" answer might require "another few years" after the collider's 2015 restart.[131] In early March 2013, CERN Research Director Sergio Bertolucci stated that confirming spin-0 was the major remaining requirement to determine whether the particle is at least some kind of Higgs boson.[132]
Confirmation of existence and current status
On 14 March 2013 CERN confirmed that:
"CMS and ATLAS have compared a number of options for the spin-parity of this particle, and these all prefer no spin and even parity [two fundamental criteria of a Higgs boson consistent with the Standard Model]. This, coupled with the measured interactions of the new particle with other particles, strongly indicates that it is a Higgs boson."[6]
Requirement | How tested / explanation | Current status (As of July 2017) |
Examining decay patterns. Spin-1 had been ruled out at the time of initial discovery by the observed decay to two photons (γ γ), leaving spin-0 and spin-2 as remaining candidates. | ||
Studying the angles at which decay products fly apart. Negative parity was also disfavoured if spin-0 was confirmed.[136] | ||
Decay channels (outcomes of particle decaying) are as predicted | The Standard Model predicts the decay patterns of a 125 GeV Higgs boson. Are these all being seen, and at the right rates? Particularly significant, we should observe decays into pairs of photons (γ γ), W and Z bosons (WW and ZZ), bottom quarks (bb), and tau leptons (τ τ), among the possible outcomes. | |
Couples to mass (i.e., strength of interaction with Standard Model particles proportional to their mass) | Particle physicist Adam Falkowski states that the essential qualities of a Higgs boson are that it is a spin-0 (scalar) particle which also couples to mass (W and Z bosons); proving spin-0 alone is insufficient.[133] | Couplings to mass strongly evidenced ("At 95% confidence level cV is within 15% of the standard model value cV=1").[133] |
Higher energy results remain consistent | After the LHC's 2015 restart at the higher energy of 13 TeV, searches for multiple Higgs particles (as predicted in some theories) and tests targeting other versions of particle theory continued. These higher energy results must continue to give results consistent with Higgs theories. | Analysis of collisions up to July 2017 do not show deviations from the Standard Model, with experimental precisions better than results at lower energies.[1] |
The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution. Wikipedia
Scientific achievements
Computer science
Particle accelerators
Large Hadron Collider
Enlargement
International relations
Associated institutions
CERN
(Courtesy of Wikipedia, Encyclopedia).
European Organization for Nuclear Research Organisation européenne pour la recherche nucléaire | |
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Formation | |
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The European Organization for Nuclear Research (French: Organisation européenne pour la recherche nucléaire), known as CERN (/sɜːrn/; French pronunciation: [sɛʁn]; derived from the name Conseil européen pour la recherche nucléaire), is a European research organization that operates the largest particle physics laboratory in the world. Established in 1954, the organization is based in a northwest suburb of Geneva on the Franco–Swiss border, and has 22 member states.[3] Israel is the only non-European country granted full membership.[4] CERN is an official United Nations Observer.[5]
The acronym CERN is also used to refer to the laboratory, which in 2016 had 2,500 scientific, technical, and administrative staff members, and hosted about 12,000 users. In the same year, CERN generated 49 petabytes of data.[6]
CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research – as a result, numerous experiments have been constructed at CERN through international collaborations. The main site at Meyrin hosts a large computing facility, which is primarily used to store and analyse data from experiments, as well as simulate events. Researchers need remote access to these facilities, so the lab has historically been a major wide area network hub. CERN is also the birthplace of the World Wide Web.[7][8]
Member states | |
Formation | |
Headquarters | |
Membership | 22 countries. |
Official languages | |
Council President | |
Website | |
The convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe.[1] The acronym CERN originally represented the French words for Conseil Européen pour la Recherche Nucléaire (European Council for Nuclear Research), which was a provisional council for building the laboratory, established by 12 European governments in 1952. The acronym was retained for the new laboratory after the provisional council was dissolved, even though the name changed to the current Organisation Européenne pour la Recherche Nucléaire (European Organization for Nuclear Research) in 1954.
CERN's first president was Sir Benjamin Lockspeiser. Edoardo Amaldi was the general secretary of CERN at its early stages when operations were still provisional, while the first Director-General (1954) was Felix Bloch.[10]
The laboratory was originally devoted to the study of atomic nuclei, but was soon applied to higher-energy physics, concerned mainly with the study of interactions between subatomic particles. Therefore, the laboratory operated by CERN is commonly referred to as the European laboratory for particle physics (Laboratoire européen pour la physique des particules), which better describes the research being performed there.
Scientific achievements
Several important achievements in particle physics have been made through experiments at CERN. They include:
· 1989: The determination of the number of light neutrino families at the Large Electron–Positron Collider (LEP) operating on the Z boson peak;
In September 2011, CERN attracted media attention when the OPERA Collaboration reported the detection of possibly faster-than-light neutrinos.[19] Further tests showed that the results were flawed due to an incorrectly connected GPS synchronization cable.[20]
The 1984 Nobel Prize for Physics was awarded to Carlo Rubbia and Simon van der Meer for the developments that resulted in the discoveries of the W and Z bosons. The 1992 Nobel Prize for Physics was awarded to CERN staff researcher Georges Charpak "for his invention and development of particle detectors, in particular the multiwire proportional chamber". The 2013 Nobel Prize for physics was awarded to François Englert and Peter Higgs for the theoretical description of the Higgs mechanism in the year after the Higgs boson was found by CERN experiments.
Computer science
History of the World Wide Web (www.com)
A plaque at CERN commemorating the invention of the World Wide Web by Tim Berners-Lee andRobert Cailliau
The World Wide Web began as a CERN project namedENQUIRE, initiated by Tim Berners-Lee in 1989 and Robert Cailliau in 1990.[21] Berners-Lee and Cailliau were jointly honoured by the Association for Computing Machinery in 1995 for their contributions to the development of the World Wide Web.
Based on the concept of hypertext, the project was intended to facilitate the sharing of information between researchers. The first website was activated in 1991. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone. A copy[22] of the original first webpage, created by Berners-Lee, is still published on the World Wide Web Consortium's website as a historical document.
Prior to the Web's development, CERN had pioneered the introduction of Internet technology, beginning in the early 1980s.[23]
More recently, CERN has become a facility for the development of grid computing, hosting projects including the Enabling Grids for E-sciencE (EGEE) and LHC Computing Grid. It also hosts the CERN Internet Exchange Point (CIXP), one of the two main internet exchange points in Switzerland.
Particle accelerators
List of current particle accelerators at CERN | |
Accelerates protons or ions | |
Accelerates protons or ions | |
Accelerates protons or ions | |
CERN operates a network of six accelerators and a decelerator. Each machine in the chain increases the energy of particle beams before delivering them to experiments or to the next more powerful accelerator. Currently active machines are:
· Two linear accelerators generate low energy particles. LINAC 2 accelerates protons to 50 MeV for injection into the Proton Synchrotron Booster (PSB), and LINAC 3 provides heavy ions at 4.2 MeV/u for injection into the Low Energy Ion Ring (LEIR).[24]
· The Proton Synchrotron Booster increases the energy of particles generated by the proton linear accelerator before they are transferred to the other accelerators.
· The Low Energy Ion Ring (LEIR) accelerates the ions from the ion linear accelerator, before transferring them to the Proton Synchrotron(PS). This accelerator was commissioned in 2005, after having been reconfigured from the previous Low Energy Antiproton Ring(LEAR).
·
· The 28 GeV Proton Synchrotron (PS), built during 1954—1959 and still operating as a feeder to the more powerful SPS.
· The Super Proton Synchrotron (SPS), a circular accelerator with a diameter of 2 kilometres built in a tunnel, which started operation in 1976. It was designed to deliver an energy of 300 GeV and was gradually upgraded to 450 GeV. As well as having its own beamlines for fixed-target experiments (currently COMPASS and NA62), it has been operated as a proton–antiproton collider (the SppS collider), and for accelerating high energy electrons and positrons which were injected into the Large Electron–Positron Collider (LEP). Since 2008, it has been used to inject protons and heavy ions into the Large Hadron Collider (LHC).
· The On-Line Isotope Mass Separator (ISOLDE), which is used to study unstable nuclei. The radioactive ions are produced by the impact of protons at an energy of 1.0–1.4 GeV from the Proton Synchrotron Booster. It was first commissioned in 1967 and was rebuilt with major upgrades in 1974 and 1992.
· The Antiproton Decelerator (AD), which reduces the velocity of antiprotons to about 10% of the speed of light for research of antimatter.
· The Compact Linear Collider Test Facility, which studies feasibility for the future normal conducting linear collider project.
Large Hadron Collider
Many activities at CERN currently involve operating the Large Hadron Collider (LHC) and the experiments for it. The LHC represents a large-scale, worldwide scientific cooperation project.
The LHC tunnel is located 100 metres underground, in the region between the Geneva International Airport and the nearby Jura mountains. The majority of its length is on the French side of the border. It uses the 27 km circumference circular tunnel previously occupied by the Large Electron–Positron Collider (LEP), which was shut down in November 2000. CERN's existing PS/SPS accelerator complexes are used to pre-accelerate protons and lead ions which are then injected into the LHC.
Seven experiments (CMS, ATLAS, LHCb, MoEDAL,[25] TOTEM, LHC-forward and ALICE) are located along the collider; each of them studies particle collisions from a different aspect, and with different technologies. Construction for these experiments required an extraordinary engineering effort. For example, a special crane was rented from Belgium to lower pieces of the CMS detector into its underground cavern, since each piece weighed nearly 2,000 tons. The first of the approximately 5,000 magnets necessary for construction was lowered down a special shaft at 13:00 GMT on 7 March 2005.
The LHC has begun to generate vast quantities of data, which CERN streams to laboratories around the world for distributed processing (making use of a specialized grid infrastructure, the LHC Computing Grid). During April 2005, a trial successfully streamed 600 MB/s to seven different sites across the world.
The initial particle beams were injected into the LHC August 2008.[26] The first beam was circulated through the entire LHC on 10 September 2008,[27] but the system failed 10 days later because of a faulty magnet connection, and it was stopped for repairs on 19 September 2008.
The LHC resumed operation on 20 November 2009 by successfully circulating two beams, each with an energy of 3.5 teraelectronvolts (TeV). The challenge for the engineers was then to try to line up the two beams so that they smashed into each other. This is like "firing two needles across the Atlantic and getting them to hit each other" according to Steve Myers, director for accelerators and technology.
On 30 March 2010, the LHC successfully collided two proton beams with 3.5 TeV of energy per proton, resulting in a 7 TeV collision energy. However, this was just the start of what was needed for the expected discovery of the Higgs boson. When the 7 TeV experimental period ended, the LHC revved to 8 TeV (4 TeV per proton) starting March 2012, and soon began particle collisions at that energy. In July 2012, CERN scientists announced the discovery of a new sub-atomic particle that was later confirmed to be the Higgs boson.[28] In March 2013, CERN announced that the measurements performed on the newly found particle allowed it to conclude that this is a Higgs boson.[29] In early 2013, the LHC was deactivated for a two-year maintenance period, to strengthen the electrical connections between magnets inside the accelerator and for other upgrades.
On 5 April 2015, after two years of maintenance and consolidation, the LHC restarted for a second run. The first ramp to the record-breaking energy of 6.5 TeV was performed on 10 April 2015.[30][31] In 2016, the design collision rate was exceeded for the first time.[32] A second two-year period of shutdown is scheduled to begin at the end of 2018.
Enlargement
Associate Members, Candidates:
· Serbia became a candidate for accession to CERN on 19 December 2011, signed an association agreement on 10 January 2012 [54][55] and became an associate member in the pre-stage to membership on 15 March 2012.[45]
· Turkey signed an association agreement on 12 May 2014 [56] and became an associate member on 6 May 2015.
· Pakistan signed an association agreement on 19 December 2014 [57] and became an associate member on 31 July 2015.[58][59]
· Cyprus signed an association agreement on 5 October 2012 and became an associate Member in the pre-stage to membership on 1 April 2016. [46]
· Ukraine signed an association agreement on 3 October 2013. The agreement was ratified on 5 October 2016. [51]
· India signed an association agreement on 21 November 2016. [60] The agreement was ratified on 16 January 2017.[52]
· Slovenia was approved for admission as an Associate Member state in the pre-stage to membership on 16 December 2016. [47] The agreement was ratified on 4 July 2017.[48]
· Lithuania was approved for admission as an Associate Member state on 16 June 2017. The association agreement was signed on 27 June 2017 and ratified on 8 January 2018. [61][53]
International relations
Three countries have observer status:[62]
· Japan – since 1995
· Russia – since 1993
· United States – since 1997
Also observers are the following international organizations:
Non-Member States (with dates of Co-operation Agreements) currently involved in CERN programmes are:[63]
· Albania
· Algeria
· Argentina – 11 March 1992
· Armenia – 25 March 1994
· Australia – 1 November 1991
· Azerbaijan – 3 December 1997
· Bangladesh
· Belarus – 28 June 1994
· Bolivia
· Brazil – 19 February 1990 & October 2006
· Canada – 11 October 1996
· Chile – 10 October 1991
· China – 12 July 1991, 14 August 1997 & 17 February 2004
· Colombia – 15 May 1993
· Croatia – 18 July 1991
· Ecuador
· Egypt – 16 January 2006
· Estonia – 23 April 1996
· Georgia – 11 October 1996
· Iceland – 11 September 1996
· Iran – 5 July 2001
· Jordan - 12 June 2003. [64] MoU with Jordan and SESAME, in preparation of a cooperation agreement signed in 2004.[65]
· Lithuania – 9 November 2004
· Macedonia – 27 April 2009
· Mexico – 20 February 1998
· Mongolia
· Montenegro – 12 October 1990
· Morocco – 14 April 1997
· New Zealand – 4 December 2003
· Peru – 23 February 1993
· Saudi Arabia – 21 January 2006
· South Africa – 4 July 1992
· South Korea – 25 October 2006
· United Arab Emirates – 18 January 2006
· Vietnam
· Cuba
· Ghana
· Ireland
· Latvia
· Lebanon
· Madagascar
· Malaysia
· Mozambique
· Palestine
· Philippines
· Qatar
· Rwanda
· Singapore
· Sri Lanka
· Taiwan
· Thailand
· Tunisia
· Uzbekistan
Associated institutions
In September 2011, CERN attracted media attention when the OPERA Collaboration reported the detection of possibly faster-than-light neutrinos. Further tests showed that the results were flawed due to an incorrectly connected GPS synchronization cable.
The contribution of Islam and Muslim scholars to Scienc
Source: Scienceislam.com
Seeking knowledge is obligatory in Islam for every Muslim, man and woman. The main sources of Islam, the Quran and the Sunnah (Prophet Muhammad’s traditions), encourage Muslims to seek knowledge and be scholars, since this is the best way for people to know Allah (God), to appreciate His wondrous creations and be thankful for them.
Muslims have always been eager to seek knowledge, both religious and secular, and within a few years of Muhammad’s mission, a great civilization sprang up and flourished.
The outcome is shown in the spread of Islamic universities; Al-Zaytunah in Tunis, and Al-Azhar in Cairo go back more than 1,000 years and are the oldest existing universities in the world. Indeed, they were the models for the first European universities, such as Bologna, Heidelberg, and the Sorbonne. Even the familiar academic cap and gown originated at Al-Azhar University.
Muslims made great advances in many different fields, such as geography, physics, chemistry, mathematics, medicine, pharmacology, architecture, linguistics and astronomy. Algebra and the Arabic numerals were introduced to the world by Muslim scholars. The astrolabe, the quadrant, and other navigational devices and maps were developed by Muslim scholars and played an important role in world progress, most notably in Europe’s age of exploration.
Muslim scholars studied the ancient civilizations from Greece and Rome to China and India. The works of Aristotle, Ptolemy, Euclid and others were translated into Arabic. Muslim scholars and scientists then added their own creative ideas, discoveries and inventions, and finally transmitted this new knowledge to Europe, leading directly to the Renaissance. Many scientific and medical treatises, having been translated into Latin, were standard text and reference books as late as the 17th and 18th centuries.
Astronomy
Muslims have always had a special interest in astronomy. The moon and the sun are of vital importance in the daily life of every Muslim. By the moon, Muslims determine the beginning and the end of the months in their lunar calendar. By the sun the Muslims calculate the times for prayer and fasting. It is also by means of astronomy that Muslims can determine the precise direction of the Qiblah, to face the Ka’bah in Makkah, during prayer
The most precise solar calendar, superior to the Julian, is the Jilali, devised under the supervision of Umar Khayyam.
The Quran contains many references to astronomy:
“And it is He who created the night and the day and the sun and the moon; all [heavenly bodies] in an orbit are swimming.” [Noble Quran 21:33]
These references, and the injunctions to learn, inspired the early Muslim scholars to study the heavens. They integrated the earlier works of the Indians, Persians and Greeks into a new synthesis.
Ptolemy’s Almagest (the title as we know it today is actually Arabic) was translated, studied and criticized. Many new stars were discovered, as we see in their Arabic names – Algol, Deneb, Betelgeuse, Rigel, Aldebaran. Astronomical tables were compiled, among them the Toledan tables, which were used by Copernicus, Tycho Brahe and Kepler.
Also compiled were almanacs – another Arabic term. Other terms from Arabic are zenith, nadir, Aledo, azimuth.
Muslim astronomers were the first to establish observatories, like the one built at Mugharah by Hulagu, the son of Genghis Khan, in Persia, and they invented instruments such as the quadrant and astrolabe, which led to advances not only in astronomy but in oceanic navigation, contributing to the European age of exploration.
Geography
Muslim scholars paid great attention to geography. In fact, the Muslims’ great concern for geography originated with their religion.
The Quran encourages people to travel throughout the earth to see God’s signs and patterns everywhere. Islam also requires each Muslim to have at least enough knowledge of geography to know the direction of the Qiblah (the position of the Ka’bah in Makkah) in order to pray five times a day.
Muslims were also used to taking long journeys to conduct trade as well as to make the Hajj and spread their religion. The far-flung Islamic empire enabled scholar-explorers to compile large amounts of geographical and climatic information from the Atlantic to the Pacific.
Among the most famous names in the field of geography, even in the West, are Ibn Khaldun and Ibn Batuta, renowned for their written accounts of their extensive explorations.
In 1166, Al-Idrisi, the well-known Muslim scholar who served the Sicilian court, produced very accurate maps, including a world map with all the continents and their mountains, rivers and famous cities. Al-Muqdishi was the first geographer to produce accurate maps in color.
Spain was ruled by Muslims under the banner of Islam for over 700 years. By the 15th century of the Gregorian calendar the ruler-ship of Islam had been seated in Spain and Muslims had established centers of learning which commanded respect all over the known world at that time. There were no “Dark Ages” such the rest of Europe experienced for the Muslims in Spain and those who lived there with them. In January of 1492 Muslim Spain capitulated to Catholic Rome under King Ferdinand and Queen Isabella. By July of the same year, Muslims were instrumental in helping navigate Christopher Columbus to the Caribbean South of Florida.
It was, moreover, with the help of Muslim navigators and their inventions that Magellan was able to traverse the Cape of Good Hope, and Da Gamma and Columbus had Muslim navigators on board their ships.
Mathematics
Mathematics
Muslim mathematicians excelled in geometry, as can be seen in their graphic arts, and it was the great Al-Biruni (who excelled also in the fields of natural history, even geology and mineralogy) who established trigonometry as a distinct branch of mathematics. Other Muslim mathematicians made significant progress in number theory.
It is interesting to note that Islam so strongly urges mankind to study and explore the universe. For example, the Noble Quran states:
“We (Allah) will show you (mankind) Our signs/patterns in the horizons/universe and in yourselves until you are convinced that the revelation is the truth.”
[Noble Quran 41:53]
[Noble Quran 41:53]
This invitation to explore and search made Muslims interested in astronomy, mathematics, chemistry, and the other sciences, and they had a very clear and firm understanding of the correspondences among geometry, mathematics, and astronomy.
The Muslims invented the symbol for zero (The word “cipher” comes from Arabic sifr), and they organized the numbers into the decimal system – base 10. Additionally, they invented the symbol to express an unknown quantity, i.e. variables like x.
The first great Muslim mathematician, Al-Khawarizmi, invented the subject of algebra (al-Jabr), which was further developed by others, most notably Umar Khayyam. Al-Khawarizmi’s work, in Latin translation, brought the Arabic numerals along with the mathematics to Europe, through Spain. The word “algorithm” is derived from his name.
Abual-Rihan Al-Beruni:
Al Biruni is a renowned physicist, who determined the specific density of 18 types of precious stones. He established the rule which stated that the specific density of a body suits the volume of the water which makes it move. He also interpreted the exit of water from geysers and artesian wells in light of the theory of communicating vessels. One of the most important of al-Biruni’s many texts is Shadows which he is thought to have written around 1021. The contents of the work include the Arabic nomenclature of shade and shadows, strange phenomena involving shadows, gnomonic, the history of the tangent and secant functions, applications of the shadow functions to the astrolabe and to other instruments, shadow observations for the solution of various astronomical problems, and the shadow-determined times of Muslim prayers. Shadows are an extremely important source for our knowledge of the history of mathematics, astronomy, and physics. It also contains important ideas such as the idea that acceleration is connected with non-uniform motion, using three rectangular coordinates to define a point in 3-space, and ideas that some see as expecting the summary of polar coordinates. Topics in physics that were studied byal-Biruni comprised hydrostatics and made very accurate measurements of specific weights. He defined the ratios between the densities of gold, mercury, lead, silver, bronze, copper, brass, iron, and tin. Al-Biruni displayed the results as combinations of integers and numbers of the form 1/n, n = 2, 3, 4... 10.
Abu al-Fath Abd al-Rahman
Mansour al-Khāzini:
Abuul Fath Al-Khazni was an incomparable physicist, particularly in relation with dynamics and hydrostatics to the extent that the succeeding researchers have been startled. His theories have been still calculated in the field on kinetics at schools and universities up till now. Among these theories are the Theory of Obliquity and Inclination and the Theory of Impulse. These two theories played an important role in kinetics. A lot of historians in the field of science regard Al-Khazani the physicist of all physicists. He dedicated most of his time to study hydrostatics; he developed a device to determine the specific gravity of liquids. He further studied the issue of resistance the body faced when it got into water. Al-Khazani operated the same apparatus used by his great master Al-Beruni to determine the specific gravity of some solid and liquid materials. The measurements of Al-Khazani were so accurate that they startled his contemporaries and successors.
Al-Khazini pointed out that air had weight and power to boost things like air, adding that the weight of the object in the air weighs less than its actual weight and its condensed weight depends on the density of air. It is worth of note that these studies concreted the way for the inventions of the barometer (pressure measurement), air vacuums and pumps among others.
DISCOVERING THE LAWS OF MOTION:
When considering the laws of motion among the research in physics, Muslim scientists were the first to discover these law as follows:
LAWS OF MOTION:
The importance of the laws of motion lies in the fact that they are viewed as the backbone of the contemporary civilization. For example, the sciences of mobile machinery nowadays starting from the car, train, plane, space rockets, and transatlantic rockets, among others rely on these laws. They have aided man to invade the outer space and to land on the surface of the moon. Moreover, they are deemed the basis for all physical sciences which depend on motion. Optics is the motion of light, sound is the motion of light waves, and electricity if the motion of electrons…etc. It is well known in the east and the west that these laws had been revealed by the English scientist Isaac Newton since he published his book Principia. This fact acknowledged in the whole world and in all scientific references, including the Muslim school of course, remained till the beginning of the twentieth century when a group of contemporary physicists, most prominent Professors of Mathematics examined these laws. They checked the accessible body of Islamic manuscripts in this field and came up with the fact that Muslim scientists were the first to discover these laws. All what Newton did was to collect what had been written on these laws and formulated them in a mathematical form. Setting bias and mere theoretical speech aside, the efforts of Muslim scientists are crystal clear. They are recognized in their manuscripts which had been written seven centuries before the birth of Newton.
THE FIRST LAW OF MOTION:
The first law of motion in physics says that if the total powers that distress an object are zero, this object will stay unmoving. Likewise, a mobile object leftovers with its constant speed state unless it finds any power that shakes it, such as the friction powers. This was stated in Newton’s mathematical statement when he said “In the absence of force, a body either is at rest or moves in a straight line with constant speed”. When it arises to Muslim scientists and their role in this field, Avicenna in his book “Insinuations and Notices” (Isharat wa Tanbihat) identified the same law in his own words “You know if the object is left unaffected by external influence, it remains as it is”. It is clear that the previous statement of Avicenna regarding the first law of motion excelled that of Isaac Newton who appeared six centuries later. In this statement Avicenna asserts that the object remains at rest or at move with constant speed in a straight line unless external power influences it. That is to say that Avicenna was the first to discover the first law of motion.
SECOND LAW OF MOTION:
The second law of motion associates the total powers distressing an object and the increase of its speed, which is known as speed and this speed is in proportion with the volume of the power and has its same direction. According to Newton’s mathematical formulation, he stated that “A body experiencing a force F experiences an acceleration a related to F by F = ma, where m is the mass of the body. Alternatively, force is proportional to the time derivative of momentum”. When it comes to Muslims, Hebattullah bin Malaka Al-Baghdadi (480-560 A.H./ 1087-1164AD) indicated in his book “The Considered in Wisdom” (Al-Moatabar fil Hikma). The solidest power transfers fast and takes a short time. The stronger power leads to the faster the power and the shorter the time. If the power does not decrease, the speed does not decrease, either”. In chapter fourteen entitled the Vacuum, he pointed out that “The faster the speed, the stronger the power. The stronger the power that pushes the object, the faster the speed of the object at move, and the shorter the time spent for covering the distance”. This is exactly what Newton mathematically formulated and named the second law of motion.
THIRD LAW OF MOTION:
The third law of motion means that if two objects interact, the force the first object practices on the second object is called the power of the action, which is equal to the force the second object practices on the first object, but it holds the opposite direction. This power is called the force of the reaction”. Newton mathematically formulated this law as follows: “Every action has a reaction which is equal in magnitude and opposite in direction”.
Earlier than Newton, Abul Barakat Hebattullah bin Malaka stated in his book, The Considered in Wisdom (Al-Moatabar fil Hekma) that “In the wrestling arena, everyone has a force practiced against the other. If one of them retreated, this does not mean that his power disappears, but this retreated power still exists, because without it the second one would not need it to influence the first one”. The same meaning has been reiterated in the writings of Imam Fakhr El-Din Al-Razi in his book The Eastern Disciplines in Theology and Natural Sciences (Al-Mabaheth Al-Mashrikayyah fi Illm Al-Illaheyyat wa Al-Tabi’yyat).
He pointed out that “the circle pulled by two equal forces until it stops in the middle, it is taken for granted that each forces has practiced an action that obstructs the other”. The same concept has been asserted by Ibn Al-Hayytham in his book, The Scenes. He pointed out that "The moving object is encountered by an obstruction, and if this forces remains, this moving object retreats in the opposite direction in the same speed practiced by the first object and according to the power of obstruction”. It is vivid clear that all what has been mentioned by Muslim scientists in these texts is the origin of the third law of motion, which was formulated by Newton after he had taken its content!
At the beginning, Muslims relied on the publications of their predecessors, such as the book entitled Nature by Aristoteles in which he dealt with kinetics and the books of Archimedes which contained information on the floating bodies in water and the specific gravity of some materials. Besides, Muslims depended on the publications of Actaspus, which entailed scientific results the uplifting pump and water clocks, and Heron of Alexandria who tackled the pulley, the wheel and the law of work. Muslim scientists spared no efforts to develop the physics- related theories and thoughts of their predecessors; they managed to introduce experimentation, which is seen as the main pillar of physics.
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