The Discourses and Mathematical Demonstrations Relating to Two New Sciences (1638) was Galileo's final book and a sort of scientific testament covering much of his work in physics over the preceding thirty years. Galileo Galilei (Pisa, February 15, 1564 – Arcetri, January 8, 1642), was a Tuscan astronomer, philosopher, and physicist who is closely associated with the scientific revolution. ...

Unlike the Dialogue Concerning the Two Chief World Systems, it was not published with a license from the Inquisition; after the heresy trial based on the earlier book, the Roman Inquisition had banned publication of any work by Galileo, including any he might write in the future. After the failure of attempts to publish the work in France, Germany, or Poland, it was picked up by Lowys Elsevier in Leiden, The Netherlands, where the writ of the Inquisition was of little account. Dialogo sopra i due massimi sistemi del mondo (Dialogue Concerning the Two Chief World Systems) was Galileos comparison of the Copernican system, in which the Earth and other planets orbit the Sun, with the traditional Ptolemaic system, in which everything in the Universe circles around the Earth. ... Pedro Berruguete. ... Elseviers logo Elsevier is the worlds largest publisher of medical and scientific literature. ... Leiden (in English also, but now rarely, Leyden) is a city and municipality in South Holland, The Netherlands. ...

The same three men as in the Dialogue carry on the discussion, but they have changed. Simplicio, in particular, is no longer the stubborn and rather dense Aristotelian; to some extent he represents the thinking of Galileo's early years, as Sagredo represents his middle period. Salviati remains the spokesman for Galileo.

The Science of materials

The sciences named in the title are the strength of materials and the motion of objects. Galileo worked on an additional section on the force of percussion, but was not able to complete it to his own satisfaction. The Materials Science Tetrahedron Materials science is a multidisciplinary field focusing on functional solids, whether the function served is structural, electronic, thermal, chemical, magnetic, optical, or some combination of these. ... In physics, kinematics is the branch of mechanics concerned with the motions of objects without being concerned with the forces that cause the motion. ...

The discussion begins with a demonstration of the reasons that a large structure proportioned in exactly the same way as a smaller one must necessarily be weaker. Later in the discussion this principle is applied to the thickness required of the bones of a large animal, possibly the first quantitative result in biology. Main articles: Life All organisms (viruses not included) consist of cells, which in turn, are based on a common carbon-based biochemistry. ...

The Law of falling bodies

Galileo was the first to demonstrate and then formulate the equation for the distance d traveled by a falling object under the influence of gravity for a time t: Galileo Galilei (Pisa, February 15, 1564 – Arcetri, January 8, 1642), was a Tuscan astronomer, philosopher, and physicist who is closely associated with the scientific revolution. ...

He (Salviati speaks here) used a wood molding, "12 cubits long, half a cubit wide and three finger-breadths thick" as a ramp with a straight, smooth, polished groove to study rolling balls ("a hard, smooth and very round bronze ball"). He lined the groove with "parchment, also smooth and polished as possible". He inclined the ramp at various angles, effectively slowing down the acceleration enough so that he could measure the elapsed time. He would let the ball roll a known distance down the ramp, and used a water clock to measure the time taken to move the known distance; this clock was A tree trunk as found at the Veluwe, The Netherlands Wood is an organic material found as the primary content of the stems of woody plants, especially trees, but also shrubs. ... Molding (US) or moulding (UK) can be: moulding or molding, a decorative feature used in interior design and architecture molding or moulding, a process used in manufacturing This is a disambiguation page — a navigational aid which lists pages that might otherwise share the same title. ... The word ramp can mean one of several things: An inclined plane Wild leeks a type of road junction for a limited access major highway such as a freeway; off-ramp is an exit from the major highway to a secondary road or an access road and an on-ramp... Groove (engineering) - a slot cut into hard material. ... German parchmenter, 1568 Parchment is a material for the pages of a book or codex, made from fine calf skin, sheep skin or goat skin. ... This article is about angles in geometry. ... A water clock or clepsydra is a device for measuring time by letting water regularly flow out of a container usually by a tiny aperture. ...

"a large vessel of water placed in an elevated position; to the bottom of this vessel was soldered a pipe of small diameter giving a thin jet of water, which we collected in a small glass during the time of each descent, whether for the whole length of the channel or for a part of its length; the water thus collected was weighed, after each descent, on a very accurate balance; the differences and ratios of these weights gave us the differences and ratios of the times, and this with such accuracy that although the operation was repeated many, many times, there was no appreciable discrepancy in the results.".¹

Reactions by Commentators

"So great a contribution to physics was Two New Sciences that scholars have long maintained that the book anticipated Isaac Newton's laws of motion." ²

"Galileo ... is the father of modern physics -- indeed of modern science" -- Albert Einstein.³

Sir Isaac Newton in Godfrey Knellers 1689 portrait Sir Isaac Newton, FRS (25 December 1642 – 20 March 1727 by the Julian calendar in use in England at the time; or 4 January 1643 – 31 March 1727 by the Gregorian calendar) was an English physicist, mathematician, astronomer, philosopher, and alchemist... In the article vector quantities are written in bold whereas scalar ones are in italics. ... Since antiquity, people have tried to understand the behavior of matter: why unsupported objects drop to the ground, why different materials have different properties, and so forth. ... // What is science? There are different theories of what science is. ... Albert Einstein, by Yousuf Karsh Albert Einstein (March 14, 1879 – April 18, 1955) was a German-born Jewish theoretical physicist of Swiss and American citizenship, who is widely regarded as the greatest scientist of the 20th century. ...

The flow of time

• It should be noted that the water clock mechanism described above was engineered to provide laminar flow of the water during the experiments, thus providing a constant flow of water for the durations of the experiments, and embodying what Newton called duration. In particular, Galileo ensured that the vat of water was large enough to provide a uniform jet of water.
• Galileo's experimental setup to measure the literal flow of time (see above), in order to describe the motion of a ball, was palpable enough and persuasive enough to found the sciences of mechanics and kinematics. Time in physics, in particular, could be founded on the notion of the linear flow of time.

• But in the 20th century some authorities challenged the reality of Galileo's experiments, in particular the distinguished French historian of science Alexandre Koyré. The experiments reported in Three New Sciences to determine the law of acceleration of falling bodies, for instance, required accurate measurements of time, which appeared to be impossible with the technology of 1600. According to Koyré, the law was arrived at deductively, and the experiments were merely illustrative thought experiments.
  • Later research, however, has validated the experiments. The experiments on falling bodies (actually rolling balls) were replicated using the methods described by Galileo (Settle, 1961), and the precision of the results was consistent with Galileo's report. Later research into Galileo's unpublished working papers from as early as 1604 clearly showed the reality of the experiments and even indicated the particular results that led to the time-squared law (Drake, 1973)⁴.

A water clock or clepsydra is a device for measuring time by letting water regularly flow out of a container usually by a tiny aperture. ... Laminar flow (bottom of pic) and turbulent flow (top of pic) over a submarine hull. ... In physics, the treatment of time is a central issue. ... In physics, the treatment of time is a central issue. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... The history of science and technology (HST) is a field of history which examines how humanitys understanding of science and technology has changed over the millennia. ... Alexandre Koyré (1882-1964) was a French philosopher of Russian origin who wrote on history and the philosophy of science. ... Events January 14 – Hampton Court conference with James I of England, the Anglican bishops and representatives of Puritans September 20 – Capture of Ostend by Spanish forces under Ambrosio Spinola after a three year siege. ...

Notes

• Note 1: Galileo 1638 Discorsi e dimostrazioni matematiche, intorno á due nuoue scienze 213, Leida, Appresso gli Elsevirii (Louis Elsevier), or Mathematical discourses and demonstrations, relating to Two New Sciences, English translation by Henry Crew and Alfonso de Salvio 1914. Section 213 is reprinted on pages 534-535 of On the Shoulders of Giants:The Great Works of Physics and Astronomy (works by Copernicus, Kepler, Galileo, Newton, and Einstein). Stephen Hawking, ed. 2002 ISBN 0-7624-1348-4

• Note 2: Stephen Hawking, ed. p. 397, On the Shoulders of Giants.
• Note 3: Stephen Hawking, ed. p. 398, On the Shoulders of Giants.
• Note 4: Stillman Drake (1973). "Galileo's Discovery of the Law of Free Fall". Scientific American v. 228, #5, pp. 84-92.

Galileo can refer to: Galileo Galilei, astronomer, philosopher, and physicist (1564 - 1642) the Galileo spacecraft, a NASA space probe that visited Jupiter and its moons the Galileo positioning system Life of Galileo, a play by Bertolt Brecht Galileo (1975) - screen adaptation of the play Life of Galileo by Bertolt Brecht... Events March 29 - Swedish colonists establish first settlement in Delaware, called New Sweden. ... 1914 is a common year starting on Thursday. ... Nicolaus Copernicus (in Latin; Polish Mikołaj Kopernik, German Nikolaus Kopernikus - February 19, 1473 – May 24, 1543) was a Polish astronomer, mathematician and economist who developed a heliocentric (Sun-centered) theory of the solar system in a form detailed enough to make it scientifically useful. ... Johannes Kepler Johannes Kepler (December 27, 1571 – November 15, 1630), a key figure in the scientific revolution, was a German astronomer, mathematician and astrologer. ... Galileo can refer to: Galileo Galilei, astronomer, philosopher, and physicist (1564 - 1642) the Galileo spacecraft, a NASA space probe that visited Jupiter and its moons the Galileo positioning system Life of Galileo, a play by Bertolt Brecht Galileo (1975) - screen adaptation of the play Life of Galileo by Bertolt Brecht... Sir Isaac Newton in Godfrey Knellers 1689 portrait Sir Isaac Newton, FRS (25 December 1642 – 20 March 1727 by the Julian calendar in use in England at the time; or 4 January 1643 – 31 March 1727 by the Gregorian calendar) was an English physicist, mathematician, astronomer, philosopher, and alchemist... For other topics related to Einstein see Einstein (disambiguation). ... Hawking as himself on Star Trek TNG Stephen William Hawking, CH, CBE, FRS (born January 8, 1942, in Oxford, England) is one of the worlds leading theoretical physicists. ... 2002 is a common year starting on Tuesday of the Gregorian calendar. ... Hawking as himself on Star Trek TNG Stephen William Hawking, CH, CBE, FRS (born January 8, 1942, in Oxford, England) is one of the worlds leading theoretical physicists. ... Hawking as himself on Star Trek TNG Stephen William Hawking, CH, CBE, FRS (born January 8, 1942, in Oxford, England) is one of the worlds leading theoretical physicists. ... Scientific American is one of the oldest and most serious popular-science magazines. ...

Sources

• Dialogues Concerning Two New Sciences, translated by Henry Crew and Alfonso di Salvio, Prometheus Books, 1991. ISBN 0879757078. The classic source in English, published in 1914.

• Two New Sciences, translated by Stillman Drake, University of Wisconsin Press, 1974. ISBN 0299064042. A new translation including sections on centers of gravity and the force of percussion.

• Titles of the first editions taken from Leonard C. Bruno 1989, The Landmarks of Science: from the Collections of the Library of Congress. ISBN 0-8160-2137-6 Q125.B87