Galileo Galilei

Galileo Galilei - Portrait of Justus Sustermans, 1636
fixed image; Uffizien, Florenz

Galileo Galilei (* 15. February 1564 in Pisa; † 8. January 1642 in Arcetri with Florenz) was an Italian mathematician, physicist and Astronomer, who made innovative discoveries in several areas of the natural sciences.

Table of contents

lives and work

origin and Lehrjahre

Galileo Galilei originated from onebecame impoverished Florentiner Patrizierfamilie. Its branch of family had accepted the name of an important ancestor, the physician Galileo Bonaiuti (15. Century). Galileis father Vincenzo was a cloth dealer, musician and music theoretician and had as such also mathematical knowledge and interests; it examined the connectionbetween string tension and pitch and thereby those discovered perhaps first nonlinear relationship of physics. It is probable that the young Galileo learned not only systematic experimental investigations in combination with strictly mathematical formulation of its father, but also thatAversion to accept age-old authorities uncritical.

Galilei was educated as Novize in a monastery and showed inclination, into the Benediktiner - medal to occur, became however from its father (alleged?) because of an eye inflammation home gotten and then to the medicine study after Pisa sent (1580). He, he said many later had played with the thought to become painters; also it was recognized a good sound player. After four years it broke its study off and went to Florenz over Ostilio Ricci, a scholar from the school of Niccolò Tartaglia to study mathematics. It denied its living costs with private instruction, was occupied with applied mathematics, mechanics and hydraulics, and begun in the formed circles of the city with lecturesto make attentive and manuscripts on itself. Before the Accademia Fiorentina it shone with a geometrical-philological paper on the Topografie of Dantes hell (Due lezioni all'Accademia fiorentina about la figura, sito e grandezza dell'Inferno di Dante, 1588).1585/86 it published first results for the weight of firm bodies (Theoremata about centrum gravitatis solidorum) and solved an antique problem (Heron) by construction of a hydrostatic balance for the determination of the specific weight (La bilancetta, manuscript).

Lectorin Pisa, 1589-1592

in the year 1589 it received a place as a lector for mathematics at the University of Pisa. The wages were hardly enough for surviving; it succeeded to Galilei nevertheless to build and sell excellent instruments. Also it developed in- still very inaccurately working - thermometer. It examined the oscillating motion and found that the period does not depend on deflection or the weight of the pendulum. Into his last Lebensjahre busy it the problem, like one this discoveryfor the construction of a pendulum clock to use can.

For the investigation of the Fallgesetze (on the basis of the oscillating motion) Galilei introduced the inclined level with balls from different materials as experimental assembly. This ingenious idea permitted it for the first time, the speed - slowly rolling -To measure balls. Thus he discovered acceleration and the fact that this something of the speed completely different is. This again could be represented at the best in the Formelsprache of mathematics. (Galileis pupil and first bio count Vincenzo Viviani setthe statement into the world, Galilei undertook Fallversuche of the inclined tower in Pisa also; in Galileis writings and manuscripts is however no reference to such attempts, which would have been quantitatively not evaluable for lack of sufficiently exact clocks. Of it toodifferentiates is the tower argument as thought experiment, on the Galilei with respect to its Hauptwerk „Dialogo “is very probably received.)

Galilei summarized the results of its mechanical investigations in a manuscript , that today as De motu antiquiora is quoted andonly 1890 [?] one printed. To it contained attacks on Aristoteles were unfriendly taken up by its conservative colleagues to Pisa and are to have led to the fact that Galileis employment was not extended 1592.

Galileis material situation was intensified by the fact that 1591 itsFather had died. It had to provide for its nut/mother, for three younger brothers and sisters and for the dowry of its older sister.

Professor in Padua, 1592-1610

thanks of good Protektion was appointed Galilei 1592 to the chair for mathematics in Padua, to thatalso Giordano Bruno hopes had made itself. In Padua, which to the rich and liberal Republic of Venice belonged, Galilei remained long 18 years. It is to have called this time later the luckiest of its life.

Although its place was substantially better endowedwhen the previous in Pisa improved, Galilei its Salär up, by giving private instruction to distinguished pupils apart from its academic lectures, among them two later cardinals. Furthermore Galilei sold forerunners of the slide rule, which was called „Compasso “starting from 1597 one „Proportionszirkel “-- its construction it had substantially improved and for its manufacturing it its own mechanic busy. Already in this year it showed in a letter at Johannes Kepler clearly, what it held from the heliozentrischen world system: „… our teacher Kopernikus,one laughed “.

Those today after Kepler designated supernew facts of 1604 caused it to three public lectures, in which he attacked the aristotelische astronomy and nature philosophy. From the fact that no parallax could be determined, it concluded Galilei (like already 1572 Tycho de Brahe) that the new star must be removed far from the earth, thus in the fixed star sphere is. After dominant teachings this was constantly held for - a further argument against the opinions „of the Peripatetiker “,as one called the Aristoteles pupils. It continued its investigations to the movement laws also in these years.

Aufzeichnungen zu Galileis Entdeckung der Jupitermonde (1610)
1609 Galilei of in the year before the telescope invented

in Holland von Jan Lippershey experienced recordings to Galileis discovery of the Jupitermonde ( 1610 ).He built equipment with approximately quadruple enlargement from available lenses, learned then even lenses to sharpen, and reached soon an eight to ninefold, in later years up to 33fache enlargement. Galilei led its instrument, its military use on thatHand was present (it supplied upright-standing illustration contrary to the Kepler telescope), the venezianischen government, the Signoria, made deep impression and left to it (completely illusory) the exclusive right for the production of such instruments, whereupon its content trebled [doubled after other source]became. Against the representation in Brechts drama did not spend Galilei the philosophy of the telescope probably as its own invention; a reduction in salary [- suspension?] in the following year suggests however that the Signoria felt led behind the light quite.

Asone of first humans used Galilei a telescope for sky observation. This meant a revolution in the study of the heavenly bodies, because up to then humans were dependent on observations with the naked eye. With it the telescope astronomy began. It determined,that the surface of the moon is uneven rau and, with collections and gaps. It recognized that the dark portion of the lunar surface is lightened by the earth („earth light “). It continued to state that the planets - contrary tothe fixed stars - when disks are to be seen and discovered the four largest moons of the Jupiter, which it in preparation of its change at the Medici - yard the Medicei Gestirne called, and which is called today the Galilei moons.He observed the fact that the Milky Way is not a foggy thing (like it seems to the naked eye), but from innumerable individual stars exists. These discoveries (including a feather/spring design of the lunar surface of it), publishes in the Sidereus Nuncius (star messenger) of 1610,Galilei made at one blow famous. The Sidereus Nuncius was out of print within fewer days.

Feather/spring design from the Sidereus Nuncius and photo

yard mathematician in Florenz, starting from 1610

in the autumn 1610 appointed the Grand Duke of the Toskana, Cosimo II.(its former pupil),Galilei to the yard mathematician and - philosophers and to the first mathematics professor in Pisa - without each training obligation: he got full liberty to dedicate itself to the research completely.

At the latest during the resettlement after Florenz separated Galilei from Marina Gamba, its lady housekeeper, alsowhich it had three children: Virginia (medal name Maria Celeste, 1600-1634), Livia (medal name Arcangela, 1601-1659) and Vincenzio (1606-1669). With the help of a Bewunderers, the cardinal Maffeo Barberini (late Pope Urban VIII.), still brought its daughters to Galilei before reaching the minimum age in oneHardly prospects had monastery under it on an according to rank marriage as illegitimate children. The son was sent 1613 to his father after Florenz, after Marina Gamba had married a man named Giovanni Bartoluzzi; Galilei legitimized it later.

Further astronomicalIt continued and found discoveries and

the procedure of 1616 Galilei his astronomical observations that the planet has Venus phases like the moon. This could only mean that the Venus occasionally beyond the sun, at other times however between sunand earth stands. Over it it corresponded with the Roman Jesuiten around Christoph Clavius (with which it had already led 1587 a controversy discussion), which had discovered the phase shape of the Venus already independently of it. Over the cosmological consequences - that Ptolemäi conception of the world was not longer durable - itself the mathematicians and astronomer of the society were more or less Jesu in the clear one.

In its enthusiasm for its scientific realizations it sent manufactured telescopes in its workshop to friends and other scientists.However only few copies achieved the desired resolving power. So it could happen that some the Jupitermonde etc. not to recognize could and it intentions to deceive subordinated. In the year 1611 visited Galilei Rome, was honoured for its discoveries highly and madeby means of his telescope its friends - under it also Jesuiten - immediately „le cose nuove del cielo “(those again [discovered] EN of articles in the sky) accessible: the Jupiter with its four companions, the gebirgigen, fissured moon, „gehörnte “(i.e. crescent-shaped) Venus and „the three-way “Saturn. He was appointed the sixth member of the Accademia dei Lincei; this honour was so important to it that it called itself from now on Galileo Galilei Linceo. With this stay it had an audience with Pope Paul V.and it met itsold Bewunderer Maffeo Barberini. One year later participated Barberini, than Galileo disproved a further untenable statement of the Aristoteles through a simple, but convincing experiment: Ice swims on water not because it (more heavily, but) is flat, butbecause it is easier.

The discovery of the sunspots entangled it into an argument with the Jesuiten Christoph Scheiner: one argued both about the priority and about the interpretation. In order to save the perfection of the sun, Scheiner tookon that marks the satellites are, against what Galilei stated the observation the fact that sunspots develop and offense (Lettere solari, 1613, one of the first scientific works, which was written not in Latin language, but in colloquial language).

For Galilei was itobviously that its astronomical observations supported the heliozentrische conception of the world of the Nikolaus Kopernikus, but it supplied no compelling proof: all observations (for instance the Venus phases) were compatible also with the model of the Tycho Brahe, in itself sun and moon around the earth,the remaining planets however around the sun turn. (It actually succeeded to prove only in the year 1729 with the stellar aberration the independent movement of the earth to James Bradley in relation to the fixed star sphere.) Galilei held back itself with the interpretation of its astronomical observations first.Against the Kopernikani system Bible places nevertheless spoke, from which an independent movement of the sun had to be judged (most importantly the place, in which Josua of the sun instructs, to stand still [Jos. 10, 12]). However was it - probably already in his timein Pisa - the thought come, „the reversals “(revolutiones) of the earth around their axle and around the sun are the cause for tides: waters are accelerated thereby and moved back and forth. Thus believed he, a proof forthe kopernikanische conception of the world in hands to have (only Isaac Newton showed that not the centrifugal energy, but the attraction of the masses of moon and sun for ebb-tide and tide is causal).

Galilei arranged controversy discussions at the Florentiner yard then nevertheless,to explain that a Bible interpretation compatible with the Kopernikani system is possible (letter to its pupil and successor in Pisa, Benedetto Castelli, 21. December 1613 original text; Letter to the Grand Duchess nut/mother Christine of Lorraine, 1615 original text, however only1636 publish). To represent the letter at Castelli passed on in incorrect copy of the Inquisition, which arranged Galilei to afterwards-send a correct copy and travel to person to Rome, in order its point of view.

In March 1614 it succeeded to Galilei, the specificTo determine weight of air as a 660stel of the weight of the water - dominant opinion was up to this time that air does not have any weight. This was a further refutation of aristotelischer opinions. In this time it was frequent as a consultantfor the Grand Duke in technical-physical questions actively; as a researcher busy it itself in particular with hydrodynamics, refraction of light in glass and water as well as mechanics (acceleration). In the years 1610-1614 it held itself frequently on the Landgut of its friend Salviati up, overto restore its health fastened for years.

In the year 1615 the cleric published Paolo Antonio Foscarini (C. 1565-1616) a book, which should prove that the Kopernikani astronomy did not contradict the holy writing. Thereupon the Roman Inquisition opened after preliminary work of the important Church teacher cardinal Robert Bellarmin an investigation procedure. 1616 were gebannt Foscarinis book. Some not-theological writings were set at the same time over Kopernikani astronomy, under it also a work by Johannes Kepler, on the index. The Hauptwerk of the Kopernikus, De Revolutionibus Orbium Coelestium,in its death year 1543 published, one did not forbid, but suspends „“: it was allowed to only appear from now on until 1822 in the sphere of influence of the Roman Inquisition in working on, which stressed that the heliozentrische system was a bare mathematical model.

At this procedure (itwas not no Inquisitionsprozess) was Galilei officially involved. Its attitude was however an open secret, even if the letter to the Grand Duchess nut/mother (still) were not published. Bellarmin wrote few days after the formal index adoption of resolutions Galilei a letter with thatInsurance, Galilei had to swear off no teachings; at the same time however this letter contained the serious admonishment to defend the Kopernikani system in no way as fact to discuss but if necessary as hypothesis. This letter became during the process of 1632/33 as prooffor Galileis disobedience quotes. However there were two different versions in the documents, by which only one was correctly signed and set, why in 19. and 20. Century some historians accepted, the Inquisitionsbehörde to the disadvantage of Galileis had falsified a proof.

Galileiheld back itself from now on in the public with the Kopernikani system. Starting from 1616 it concerned itself intensively with the possibility of using the movements of the Jupitermonde as Zeitmesser in order to solve the degree of longitude problem (unsuccessfully). It converted the telescopefor the first time into a microscope; the microscopy remained for it however an occupation of low priority.

The dialogue over the two world systems

Titelblatt von Galileis Dialog: Aristoteles, Ptolemäus und Kopernikus diskutieren
title page of Galileis dialogue: Aristoteles, Ptolemäus and Kopernikus discuss

1623 became Galileis of old promoters, cardinal Maffeo Barberini, the Popeselected (Urban VIII.). Galilei dedicated immediately its writing Saggiatore , a Polemik to him against the Jesuitenpater Orazio Grassi over the comet features of 1618/1619, over atomistic and methodologische questions. In this book, on which he had worked since 1620,Galilei expressed its famous conviction become, philosophy (after the linguistic usage of the time with it the natural science is meant) is located in the book of nature, and this book was written in mathematical language: without controlling geometry, one does not understand noneWord. Since that time Galilei is considered as a founder of the modern, mathematically oriented natural sciences, at the same time contained this a clear refusal at Alchemie and Astrologie.

In the Saggiatore it interpreted the comets as near earth optical effects (comparable phenomena such as rainbow or north light), thereinfalling back to a theory of the Aristoteles about Meteore. At present the comet features was not Galilei however for health reasons able to employ even observations. Its empirically not founded Polemik against the theory of the comets, the Tycho Brahe andOrazio Grassi represented, are as indirect defense of the kopernikanischen system to be understood, which would have been threatened by the acceptance on circular paths of not moving heavenly bodies.

With this Polemik Galilei animated the old enmity of some Jesuiten. One of the consequences was oneanonymous announcement of the Saggiatore because of atomicism and thus offence against the dogmas of the tridentischen council concerning the communion. With help of a complaisance appraisal Pater Giovanni Guevaras the sponsors Galileis in the Vatikan let this announcement versanden. The science historian Pietro Redondi assumestherefore that also the process 1633 an announcement is the basis because of atomicism and thus shedding tables opinions concerning the communion, however by intervention of the particularly created papal commission of inquiry on the far less explosive question of the Kopernikanismus and/or. the disobedience one diverted.

1624 traveled Galilei to Rome and six times from Barberini Urban were received, which encouraged it to publish over the Kopernikani system as long as he as hypothesis treat this; from the year 1616 Barberini knew the letter of Bellarmin at Galilei at that timenot. After long pre-working and again interrupted by diseases completed Galilei 1630 the Dialogo di Galileo Galilei sopra i due Massimi Sistemi del Mondo Tolemaico e Copernicano (dialogue over the two most important world systems, Ptolemäi and Kopernikani). In thisBook explained among other things its relativity principle and its suggestion on the determination of the speed of light ( the first precise measurement of the speed of light on earth only 1849 Fizeau succeeded .) to Galilei. As allegedly the strongest argument for the Kopernikani system its served it -wrong - theory of tides.

In May 1630 Galilei traveled again to Rome, over with Urban VIII. and Niccolò Riccardi, that for the censorship responsible person Inquisitor to obtain a church pressure permission (imprimatur). It received also a provisionalPressure permission. Back in Florenz Galilei decided however for different reasons, among other things because the publisher (prince Cesi, founder of the Accademia dei Lincei) had deceased and because of a plague epidemic disease to be content with a pressure permission by the Florentiner Inquisitor and thatTo let print work in Florenz. Due to different difficulties, released by Riccardi, the pressure could begin however only in July 1631; in February 1632 „the Dialogo appeared “.

The censorship edition, the work with a closing speech in favor of the Ptolemäi systemto decide, Galilei meant to follow, by putting this speech into the mouth communist manifestos of the fool Simplicio. Besides he committed the error to make itself merry over a favourite thought Barberini Urbans: that one a theory never about their predicted ofEffects to prove knows, since God can bring these effects out at any time also on other way. Thus Galilei had spanned the elbow and the Protektion of the Pope playful, who - possibly also for reasons with regard to foreign policy - reacted now with full hardness.

ThatProcess against the dialogue

in July 1632 white Riccardi the Inquisitor from Florenz, it is to prevent the spreading of the Dialogo. In September the Pope ordered Galilei to Rome in. With request for delay, medical certificates, lengthy journey and in addition Quarantine due to the plague epidemic disease passed however the entire winter. In Rome Galilei in the residence of the toskanischen Ambassador lived. At the beginning of of April 1633 it was officially heard and had to refer an apartment of the Inquisition for 22 days. To 30. April well-knownit in a second hearing in its book to have erred and was allowed again into the toskanische message back. To 10. May submitted it its written defense, a request for grace. To 22. June 1633 found the process inthe Basilika Santa Maria sopra Minerva instead of. First Galilei denied referring to the dialogue form of its work, the kopernikanische system to have taught. The Bellarminbrief (which version, is not well-known) became reproached to it and it the disobedience accuses of. After it itsErrors abgeschworen, they verflucht and had abhorred, it to lifelong dungeon detention was condemned. The fact that Galilei was at all condemned was quite contentious among the responsible ten cardinals; three of them (under it Francesco Barberini, the nephew of the Pope) did not sign the judgement.

Galilei held to its conviction. The statement, according to which it is to have murmured when leaving the court room, „Eppur SI muove “(and it (the earth) moves nevertheless), is wrong. It was however already spread during its lifetimes, howa Spanish painting of approx. 1643/45 show. These words were mentioned for the first time 1757 in „the Italian LIBRARies “by a Giuseppe Baretti.

Galilei regarded time life the circular paths as a central component of the Kopernikani system and leaned elliptical courses for this reasonoff. Kepler, with which he stood in letter contact, had eliminated all inconsistencies between observation and the heliozentrischen conception of the world with its model of the elliptical orbits practically. For the rescue of its concept of the circular paths Galileo took in purchase that it the observed position of thePlanet Mars substantially more badly forecast than the geocentric models of Ptolemaios or Brahe.

The fact that Galilei the comets uminterpretierte to atmospheric features, because the alternative explanation of objects around-moving in the solar system would have endangered its conception of the world, might the reliability of its modelbeen likewise rather detrimental its. With the sunspots was added that the sun fell after 1610 for nearly 40 years into extreme an activity minimum, in which it as well as no observable sunspots more gave. I.e. by this mood thatNature could supply no more vouchers to Galilei with for these observations. In addition it discussed the two world systems of Kopernikus and Ptolemaios in its dialogue wohlweislich only, (it had the latter on the basis the Venusphasen empirically disproved), not however the geocentric model of Brahe,with his observations likewise got along.

House arrest 1633-1642 and the Discorsi

Galilei remained after the judgement under detention (in the message of the duchy Toscana in Rome). After few weeks it was placed into the supervision of the archbishop by Siena,however its glowing Bewunderer was and it after forces supported. In Siena it could overcome its deep Niedergeschlagenheit over the process and its exit. After five months (December 1633) it was allowed to return to its mansion „Gioiella “to Arcetri, remainedhowever under house arrest, connected with the prohibition of any training activity. When it asked because of a painful border break for permission to be allowed to visit physicians in Florenz its request with the warning, further such inquiries became rejected abolition of the house arrestand Einkerkerung lead. In accordance with the judgement it had the seven Busspsalmen (over three years long) to pray weekly (this obligation took over - so long it lived - its daughter Suor Celeste), and its social contacts was strongly limited. Nevertheless was it it permits to continue with its fewer controversies research and to visit its daughters in the monastery San Matteo. All publications were forbidden to it, however it led an expanded exchange of letters with friends and scholars at home and abroad and could latertemporarily visitors receive (under it Thomas Hobbes and John Milton, starting from 1641 its former pupil Benedetto Castelli).

Galilei had problems with its eyes since longer; 1638 it went blind completely - possibly a consequence to its at first without sufficient protection undertakenSun observations. However he discovered the Libration of the moon still briefly before the complete loss of his sight. A request for grace on release was rejected. Its he spent last years in his country house in Arcetri.

Starting from July 1633 - still in Siena- had worked Galilei on its physical Hauptwerk Discorsi e Dimostrazioni Matematiche intorno A due nuove scienze. Although the Inquisitionsurteil did not contain explicit publication prohibition, a publication in the sphere of influence of the catholic church turned out as impossible. Latin a translation thatDiscorsi appeared 1635 with Matthias Bernegger in Strasbourg, the Italian original 1636 with Louis Elsevier in suffering.

Contentwise Galilei reached into the Discorsi beginnings and results from its early years. The two new sciences, thoseGalilei therein justified, are in modern language elasticity theory and kinetics. He knows among other things after that the arc-shaped movement of a projectile consists of two components: the horizontal is determined by the inertia, the downward directed against it by more constantAcceleration. Cooperating both leads to a parabelförmigen flight path.

In the late autumn 1641 the talented Evangelista Torricelli replaced its (since 1637) companion of many years Vincenzo Viviani as assistant and a private secretary, but was already clear to live that Galilei any longer longhad. It died to 8. January 1642 in Arcetri. A solemn funeral in a splendid grave, which the Grand Duke had planned, was prevented.

Grab des Galileo, Santa Croce, Florenz
Grave of the Galileo, Santa Croce, Florenz

Galileo and the church

Landläufig become the policy of the office church Galileounderstood their allegedly inherent science and progress hostileness in relation to as a sign of one. This view can be however also analyzed. To Galileis time was already split the hierarchy. The superiority of the new sciences was not less obvious for the Popes and cardinalsas for their opponents. On the other hand they, after they had only succeeded straight to strengthen in the fight against the reformation assistance of the Dominikaner - and Jesuitenorden their influence in Italy again had the promotion of the sciences in Great Britain, Holland andGermany as continuing attacks on the explanation sovereignty of their institutions - the dekretierten Consensus patrum - interpret. In the defense fight against the up-pulling clearing-up they saw themselves forced to from today's viewpoint rigid-intimate persisting in the traditional one. God justifies the earth circle immovably… (1.Chronik 16.30).

At the same time there were already at that time powerful church voices, which had departed from the literal interpretation of the writing and which was argumentation, faith and science separate spheres, had accepted. E.G. cardinal Bellarmin, an important theologian and central wrotePersonality of the Kurie and Inquisition that one would be present, a real proof for the heliozentrische system, during the interpretation of the holy writing indeed carefully proceed must. Galileo meant to have with its tidal theory such a proof. Itit seems that Galilei could have gotten more support, if its occurrence the Klerus had been only modest opposite enough. Expression of church ambivalence opposite it is the quite mild admonishment of 1616, Galilei is in „the mistake of the faith “and likestherefore „from a spreading of the kopernikanischen conception of the world refrain “.

Only after Galilei polemisierte 1632 with the Dialogo again for the kopernikanische conception of the world, and the first copies also still at its avowed opponents (e.g. ), became a formal procedure sent to the Inquisitor Serristoriagainst it opens. The climate - compared to other Ketzerprozessen, which led to torture and heap of failure - was friendly still still and the judgement mild. After Galilei had sworn… to have always believed to believe at present and in the futurewith God assistance to believe to want everything what considers, preaches and taught the catholic and apostolische church true, it received „only “dungeon detention, which was already converted after few weeks into house arrest.

The Tragik of Galileos working liesin the fact that it - when time life a tiefgläubiges member of its church - which attempt undertook to protect this church a fatal mistake. Its intention was not it to disprove or split the church, but rather was it ona reform of the world view of the church convenient. Its different stay in Rome up to the year 1616 had also the purpose to convince church men such as Bellarmin of the fact that the Peripatetiker was not infallible and the holy writing not always literally readwill must. Also Galilei of the conviction was to be able to clarify the marvelous works of the gentleman by experiment and logic (sooner or later) completely; Pope Urban VIII.on the other hand it remained with his opinion that the various natural phenomena, which the allpowerful causes itselfalways extract from the limited understanding of humans - a certain theory skepticism formulates also Albert Einstein: „The theory supplies much, but the secret of the old person (sports club God) it hardly näherbringt to us. “

Nachgeschichte, Nachruhm

of the Inquisitionsprozess against Galilei hasto endless historical controversies and numerous literary working on lively; among other things in Bertolt Brechts life of the Galilei.

1741 granted the holy Offizium - i.e. the Inquisition - on request Benedikts XIV.imprimatur on the first total expenditure of the worksGalileis. Under Pius VII. if 1822 were given for the first time imprimatur on a book, which treated the Kopernikani system as physical reality - the author, a certain Settele, was Kanoniker. For non--clerics the Interdikt had become inconsequential probably long.

1979 assigned Johannes Paul II. the papal Academy of Sciences to regenerate the famous case. To 31. October 1992 was handed over the commission report, and held Johannes Paul II. a speech, which is represented often shortened as a bare apology; actuallyit concerned to the Pope to heal the mutual misunderstanding from science and church to. To 2. November 1992 was formally rehabilitated Galileo Galilei by the Roman-catholic church.

Scientific achievements


Galilei those belonged of to the first scientists, Francis Bacon theoretically called in experimental method obeyed (he did this however, before Bacon had published its demand); however Galilei insisted at the same time on a strictly mathematical description of the laws of nature, if directly he did not use us today the common algebraic notation yet.Galileis superiority feeling opposite Aristoteles based perhaps primarily on the fact that he meant to be the better mathematician.


the evenly accelerated movement busy Galilei over forty years long. Its experimental innovation existed in the use of the inclined level, with which itthe Fallgesetze on a slowed down time scale to study and - over its pulse or with Wasseruhren - quantitatively examine knew.

In its early manuscript De motu (1590, s.o.) it held still the opinion, acceleration depends on the density. Laterhe came then in the end that in the vacuum all bodies experience the same acceleration. In connection with the tower argument kinematic considerations in the dialogue are over the two world systems; fully to be prepared the Fallgesetze in third and fourth of the fourDays of the Discorsi e Demonstrazioni of 1636/38.

With it together hangs closely the relativity principle, which is called in modern physics Galilei invariance and meant that an evenly moved observer notices the same physical laws as more stationary. Galilei came with itsIt took conclusions the first movement law Isaac Newton quite close, second in certain way already in front (which added Newton later).

Newer science-historical work stress that Galilei with its research did not stand to the kinetics alone; with the topic concerneditself among other things Alessandro Piccolomini, Niccolò Tartaglia, Giovan Battista Benedetti, Francesco Maurolico, Bernardino Baldi, Guidubaldo del Monte, Michael Varro (De motu, Geneva 1584) and Francesco Buonamicida (De motu, Florenz 1591).

Christiaan Huygens developed later its idea of clock mechanics steered by a pendulum for practical use.

Elasticity theory

as from the title discorsi goes, to published Galilei out its results over the elasticity of a bar with full consciousness, thereby a new scienceto justify. The further development gave it right; its contribution can actually be considered as reason of the elasticity theory.

Galilei stated that the load-carrying capacity of a bar is larger, if one does not place it upright, to flat Kant. It set as first thoseexpresses load in relation to the internal tensions. It could not set up a quantitative theory however yet. Today neutral surface quantity mentioned of all axes of rotation it arranged those at the lower edge of the clamped bar instead of in the center of the bar cross section. Correctionsthis mistake could itself in 17. and 18. Century do not implement; only at the beginning 19. Century successfully provided Navier for a rectification.

Were appreciated of astronomy Galileis astronomical discoveries already in detail in the biographic part.

Christiaan Huygens recognized that behind that„Three-shape “of the planet Saturn actually a ring puts.

Galileis of attempts to solve by means of the Jupitermonde the length problem set oils of Romans away (also it here unsuccessfully), thereby however „besides “the propagation speed of the light (rough) determined. The first precise measurement thatSpeed of light on earth succeeded only to 1849 Fizeau.

The method for parallax regulation, suggested by Galilei , was used 1837 by Friedrich William Bessel measuring the distance of a fixed star with convincing accuracy.

Mixed inventions

several of Galileis inventions are todayreceive only in its recordings and sketches. He drew among other things sketches of devices like a combination of candle and mirror, in order to be able to lead thereby the light by the whole house, an automatic Tomatenpflücker, a bag comb, also as Cutlery to be used knew and a kind forerunner of the ball-point pen. The temperature gauge developed by it was improved by Fahrenheit (1714) crucially.

Galilei as a writer

revolutionary was not only that Galilei from 1613 on published Italian in the people language, butalso how: It wrote exemplary beautiful Italian, which affected in an educated manner the scientific Prosa.

Galileis scientific works

Galilei published its scientific realizations in the following Hauptwerken (further works, which are today from primarily biographic interest, become in thatBiografie mentioned):

  • Sidereus nuncius, 1610
    German: Message of new stars, Frankfurt A. M. 1965
  • Saggiatore (examiners with the Goldwaage), 1623
  • Dialogo sopra i due massimi sistemi, Florenz 1632
    German: Dialogue over the two main world systems, Leipzig 1891
  • Discorsie dimostrazioni matematiche, suffering 1638
    German: Conversation and mathematical demonstration over two new branches of knowledge concerning the mechanics and the Fallgesetze, Leipzig 1890

after Galilei are designated:

spoken Wikipedia

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expenditures for source

  • writings, letters, documents. (Hg. Anna Mudry), Munich 1987
  • Pietro Redondi: Galilei - the Ketzer, Munich 1989 (representation of the Inquisitionsprozesses of 1633; with partially. for the first time documents), 3-406-33981-6 Biografien Pascual


  • published ISBN: Galileo Galilei, in: The large ones of the world history, given change of briefly barrel man, Zurich1974, volume 5:Calvin to Huygens, S. 468-491 (Kurzbiografie)
  • Drake, Stillman: Galileo RK Work. Chicago: University OF Chicago press, 1978, ISBN 0-226-16226-5; on German: Freiburg 2004, ISBN 3-926642-38-6
  • Biagioli, Mario: Galilei, the Höfling. Discovery and label: OfAscent of the new science. Frankfurt A.M.: Fischer publishing house, 1999, ISBN 3-10-009628-2
  • David Freedberg: The Eye OF the Lynx. Galileo, his friends and the beginning OF decay natural history. Chicago, London 2002.


  • Bertolt break: The life of the Galilei, (Denmark, 1938/39) ISBN 3518100017. In 8. Picture brings the problem of scientific research and theological interpretation sovereignty to Galilei with famous a Aperçu become on the point: „The Winkelsumme in the triangle cannot be amended after the needs of the Kurie. “
  • Arthur Koestler: The night transducers. The picture of the universe in the change of the time, Berne - Stuttgart - Vienna 1959 (as Suhrkamp e.g. Bd. 579, Frankfurt 1988) ISBN 3-518-37079-0
  • Paul Feyerabend: Against the method obligation. Frankfurt 2001 ISBN 3518281976
  • Alexandre Koyré: Leonardo, Galilei, Pascal, Berlin 1994 ISBN 3-8031-5145-7
  • a surprising interpretation to Galileis discovery of the Jupitermonde is in the history of Andreas Venzke: The view of a new world - Galileo Galilei and the modern science (In: World history in stories, peppering castle 2004, S. 97-104 ISBN 3-401-05442-2)

see also: John Thomas Scopes

of films

  • 1947 filmed in the USA Ruth Berlau and Joseph Losey the Broadway performance of Brechts „lives of the Galileo “with Charles Laughton in thatTitle part. This concerns a black-and-white silent movie of 30 minutes of duration.
  • In a German television filming after break, „to lives of the Galilei “(1962) under the direction of Egon Monk, played Ernst Schröder the Galilei. With 150 minutes play length is that the longest conversion of the material in the television.

Web on the left of

Wikiquote: Galileo Galilei - quotations
Commons: Galileo Galilei - pictures, videos and/or audio files
  • {{#if:
| | *  Literature of and over Galileo Galilei in the catalog of the DDB


overview sides:

of primary texts:

scientific secondary source

  • [1] of Dr. D. Nix

current research:

  • Galileana international magazine for Galilei research, justifies 2004

aspect of the catholic church

This article was taken up to the list of exzellenter articles.


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