The Rosetta Stone

A valuable key to deciphering ancient Egyptian hieroglyphs, the inscription on the Rosetta Stone is a decree passed by a council of priests. It is one of a series that affirm the royal cult of the 13-year-old Ptolemy V on the first anniversary of his coronation (in 196 BC).

In previous years the family of the Ptolemies had lost control of certain parts of the country. It had taken their armies some time to put down opposition in the Delta, and parts of southern Upper Egypt, particularly Thebes, were not yet back under the government’s control. Before the Ptolemaic era (before about 332 BC), decrees in hieroglyphs such as this were usually set up by the king. It shows how much things had changed from earlier times that the priests, the only people who had kept the knowledge of writing hieroglyphs, were now issuing such decrees. The list of good deeds done by the king for the temples hints at the way in which the support of the priests was ensured.

The decree is inscribed on the stone three times, in hieroglyphic (suitable for a priestly decree), demotic (the native script used for daily purposes), and Greek (the language of the administration). The importance of this to Egyptology is immense.

Soon after the end of the 4th century AD, when hieroglyphs had gone out of use, the knowledge of how to read and write them disappeared. In the early years of the 19th century, scholars were able to use the Greek inscription on this stone as the key to decipher them. Thomas Young (1773–1829), an English physicist, was the first to show that some of the hieroglyphs on the Rosetta Stone wrote the sounds of a royal name, that of Ptolemy.

The French scholar Jean-François Champollion (1790–1832) then realised that hieroglyphs recorded the sound of the Egyptian language and laid the foundations of our knowledge of ancient Egyptian language and culture. Champollion made a crucial step in understanding ancient Egyptian writing when he pieced together the alphabet of hieroglyphs that was used to write the names of non-Egyptian rulers. He announced his discovery, which had been based on analysis of the Rosetta Stone and other texts, in a paper at the Academie des Inscriptions et Belles Lettres at Paris on Friday 27 September 1822. The audience included his English rival Thomas Young, who was also trying to decipher Egyptian hieroglyphs. Champollion inscribed this copy of the published paper with alphabetic hieroglyphs meaning ‘à mon ami Dubois’ ('to my friend Dubois’). Champollion made a second crucial breakthrough in 1824, realising that the alphabetic signs were used not only for foreign names, but also for the Egyptian language and names. Together with his knowledge of the Coptic language, which derived from ancient Egyptian, this allowed him to begin reading hieroglyphic inscriptions fully.

Soldiers in Napoleon’s army discovered the Rosetta Stone in 1799 while digging the foundations of an addition to a fort near the town of el-Rashid (Rosetta). On Napoleon’s defeat, the stone became the property of the British under the terms of the Treaty of Alexandria (1801) along with other antiquities that the French had found.

The Rosetta Stone has been exhibited in the British Museum since 1802, with only one break. Towards the end of the First World War, in 1917, when the Museum was concerned about heavy bombing in London, they moved it to safety along with other, portable, 'important’ objects. The Rosetta Stone spent the next two years in a station on the Postal Tube Railway 50 feet below the ground at Holborn.

Find out more in this BBC podcast about the Rosetta Stone.

History’s Ten Greatest Polymaths

10. Benjamin Franklin

One of the Founding Fathers of the United States. Franklin was a renowned polymath and a leading author, printer, political theorist, politician, freemason, postmaster, scientist, inventor, civic activist, statesman, and diplomat. As a scientist, he was a major figure in the American Enlightenment and the history of physics for his discoveries and theories regarding electricity. As an inventor, he is known for the lightning rod, bifocals, and the Franklin stove. He facilitated many civic organizations, including Philadelphia’s fire department and The University of Pennsylvania, an Ivy League institution.

9. Immanuel Kant

German philosopher who is regarded as one of the most important thinkers of modern Europe, and his influence on Western thought is immeasurable. He was the starting point and inspiration for the German Idealism movement in the late 18th and early 19th Centuries, and more specifically for the Kantianism which grew up around him in his own lifetime. His works, especially those on Epistemology, Metaphysics and Ethics, such as his masterworks the "Critique of Pure Reason" and the "Critique of Practical Reason,“ achieved a complete paradigm shift and moved philosophy beyond the debate between the Rationalists and Empiricists which had dominated the Age of Reason and the early Age of Enlightenment.

8. Baruch Spinoza

Dutch Philosopher who laid the groundwork for the 18th-century Enlightenment and modern biblical criticism, including modern conceptions of the self and the universe. He developed highly controversial ideas regarding the authenticity of the Hebrew Bible and the nature of the Divine. His notable ideas were Pantheism, determinism, neutral monism, parallelism, intellectual and religious freedom, and the separation of church and state. He came to be considered one of the great rationalists of 17th-century philosophy. Spinoza's magnum opus, the posthumous "Ethics,“ in which he opposed Descartes' mind–body dualism, has earned him recognition as one of Western philosophy’s most important thinkers.

7. Johann Wolfgang von Goethe

German writer and statesman. His body of work includes epic and lyric poetry written in a variety of metres and styles; prose and verse dramas; memoirs; an autobiography; literary and aesthetic criticism; treatises on botany, anatomy, and colour; and four novels. In addition, numerous literary and scientific fragments, more than 10,000 letters, and nearly 3,000 drawings by him exist.

6. René Descartes

French philosopher, mathematician, and scientist. Dubbed the father of modern western philosophy, much of subsequent Western philosophy is a response to his writings, which are studied closely to this day. Descartes's Meditations on First Philosophy continues to be a standard text at most university philosophy departments. Descartes’s influence in mathematics is equally apparent; the Cartesian coordinate system—allowing reference to a point in space as a set of numbers, and allowing algebraic equations to be expressed as geometric shapes in a two- or three-dimensional coordinate system (and conversely, shapes to be described as equations)—was named after him. He is credited as the father of analytical geometry, the bridge between algebra and geometry, used in the discovery of infinitesimal calculus and analysis. Descartes was also one of the key figures in the scientific revolution. In his theology, he insists on the absolute freedom of God’s act of creation. Descartes laid the foundation for 17th-century continental rationalism, later advocated by Baruch Spinoza and Gottfried Leibniz.

5. Archimedes

Ancient Greek mathematician, physicist, engineer, inventor, and astronomer. Although few details of his life are known, he is regarded as one of the leading scientists in classical antiquity. Generally considered the greatest mathematician of antiquity and one of the greatest of all time, Archimedes anticipated modern calculus and analysis by applying concepts of infinitesimals and the method of exhaustion to derive and rigorously prove a range of geometrical theorems, including the area of a circle, the surface area and volume of a sphere, and the area under a parabola. Other mathematical achievements include deriving an accurate approximation of pi, defining and investigating the spiral bearing his name, and creating a system using exponentiation for expressing very large numbers. He was also one of the first to apply mathematics to physical phenomena, founding hydrostatics and statics, including an explanation of the principle of the lever. He is credited with designing innovative machines, such as his screw pump, compound pulleys, and defensive war machines to protect his native Syracuse from invasion.

4. Aristotle

Greek philosopher and scientist. At seventeen or eighteen years of age, he joined Plato’s Academy in Athens and remained there until the age of thirty-seven (c. 347 BC). His writings cover many subjects – including physics, biology, zoology, metaphysics, logic, ethics, aesthetics, poetry, theater, music, rhetoric, linguistics, politics and government – and constitute the first comprehensive system of Western philosophy. Shortly after Plato died, Aristotle left Athens and, at the request of Philip of Macedon, tutored Alexander the Great beginning in 343 BC. The fact that Aristotle was a pupil of Plato contributed to his former views of Platonism, but, following Plato’s death, Aristotle immersed himself in empirical studies and shifted from Platonism to empiricism. He believed all peoples’ concepts and all of their knowledge was ultimately based on perception. Aristotle’s views on physical science profoundly shaped medieval scholarship. Their influence extended from Late Antiquity and the Early Middle Ages into the Renaissance, and were not replaced systematically until the Enlightenment and theories such as classical mechanics. Some of Aristotle’s zoological observations, such as on the hectocotyl (reproductive) arm of the octopus, were not confirmed or refuted until the 19th century. His works contain the earliest known formal study of logic, which was incorporated in the late 19th century into modern formal logic. In metaphysics, Aristotelianism profoundly influenced Judeo-Islamic philosophical and theological thought during the Middle Ages and continues to influence Christian theology, especially the Neoplatonism of the Early Church and the scholastic tradition of the Roman Catholic Church. Aristotle was well known among medieval Muslim intellectuals and revered as “The First Teacher.” His ethics, though always influential, gained renewed interest with the modern advent of virtue ethics. All aspects of Aristotle’s philosophy continue to be the object of active academic study today.

3. Leonardo Da Vinci

Italian polymath whose areas of interest included invention, painting, sculpting, architecture, science, music, mathematics, engineering, literature, anatomy, geology, astronomy, botany, writing, history, and cartography. He has been variously called the father of palaeontology, iconology, and architecture, and is widely considered one of the greatest painters of all time. Sometimes credited with the inventions of the parachute, helicopter and tank, he epitomised the Renaissance humanist ideal. Today, Leonardo is widely considered one of the most diversely talented individuals ever to have lived.

2. Isaac Newton

English physicist and mathematician (described in his own day as a “natural philosopher”) who is widely recognised as one of the most influential scientists of all time and a key figure in the scientific revolution. His book “Mathematical Principles of Natural Philosophy,” first published in 1687, laid the foundations for classical mechanics. Newton made seminal contributions to optics, and he shares credit with Gottfried Wilhelm Leibniz for the development of calculus. Newton's Principia formulated the laws of motion and universal gravitation, which dominated scientists’ view of the physical universe for the next three centuries. Newton’s work removed the last doubts about the validity of the heliocentric model of the Solar System. Newton built the first practical reflecting telescope and developed a theory of colour based on the observation that a prism decomposes white light into the many colours of the visible spectrum. He formulated an empirical law of cooling, studied the speed of sound, and introduced the notion of a Newtonian fluid. In addition to his work on calculus, as a mathematician Newton contributed to the study of power series, generalised the binomial theorem to non-integer exponents, developed a method for approximating the roots of a function, and classified most of the cubic plane curves. Beyond his work on the mathematical sciences, Newton dedicated much of his time to the study of biblical chronology and alchemy, but most of his work in those areas remained unpublished until long after his death.

1. Nikola Tesla

Serbian-American inventor, discoverer, electrical engineer, mechanical engineer, theoretical and experimental physicist, mathematician, futurist and humanitarian. Tesla was a hyperpolyglot who could speak eight languages fluently including: Serbo-Croatian, English, Czech, French, German, Hungarian, Italian, and Latin. Tesla has more original inventions to his credit than any other man in history. He has been accounted for 278 patents in 26 different countries. He was the true father of radio and a man far ahead of his time. He is best known for his contributions to the design of the modern alternating current (AC) electricity supply system that we still use today. He was the first to invent and patent a commutatorless alternating current induction motor that led to an AC/DC war with Thomas Edison. All electrical machinery using or generating alternating current is due to Tesla, without which our long distance trolley cars, our electrified power lines, and our subways would be impossible. The Tesla Induction Motor, the Tesla Rotary Converter, the Tesla Phase System of Power Transmission, the Tesla Steam and Gas Turbine, the Tesla Coil, and the Oscillation Transformer are perhaps his better known inventions. In his labs he conducted a range of experiments with mechanical oscillators/generators, electrical discharge tubes, and early X-ray imaging. He is also the father of remote control, building a wireless controlled boat exhibited in 1898. Although not recognized for, he was the first to discovery the electron, radioactivity, cosmic rays, terrestrial resonance, stationary waves (standing waves), and the first to invent fluorescent light bulbs. He first demonstrated wireless energy/power by lighting his phosphorescent light bulbs wirelessly in a demonstration given before the Franklin Institute in Philadelphia,1893. He also theorized a particle beam to be used for defense in war, and also to produce an artificial Aurora Borealis to light the night skies. In his later life he wanted to bring humanity so much more with his inventions and discoveries, but lacked the investments and funds to finish his work on a large scale. He would eventually die penniless and alone in his New York apartment, but like all the greats above, he lives on through all his inventions and contributions to this world that last until the end of man.

Splashing Droplets Can Take Off Like Airplanes

by Patricia Waldron, Inside Science

When a drop of liquid hits a solid surface, the liquid will do one of two things: flatten like a pancake or launch a halo of droplets into the air. It’s a surprisingly complex and difficult-to-predict event.   

The secret is in the air. By taking into account the gas surrounding the drop, researchers find that they can calculate just how fast a drop can travel without splattering when it hits. A new study suggests that after the drop strikes a solid surface,  a tiny cushion of air carries along its edge as it spreads. The air provides lift like on an airplane wing and flings away droplets from the drop’s edge.

See videos below.

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Quantum Physics

Dirac Notation: Introduction

See previous posts about Quantum Physics

Dirac notation (or bra-ket notation) was developed by English physicist Paul Dirac to help describe the quantum effects that were being observed in experiments of the time. Alongside Erwin Schrödinger, Dirac earned the 1933 Nobel Prize in Physics for “the discovery of new productive forms of atomic theory,” which was contributed to in part by his development of this notation.

At the fundamental level, Dirac notation is primarily comprised of state vectors and basis vectors.


Consider a quantum system (e.g. a particle) which has a state ψ. In Dirac’s notation, this is represented by the “ket” vector, or the state vector

which can represent either a discrete set of possible states or a continuous wavefunction.

In a discrete set, the state of the system is defined by a column vector representing each possible state the system may take

where each component ψi is a complex number. In a continuous set, the state is represented by a function

which essentially acts just like any complex function we’ve met previously in mathematics. 

It is worth noting here that the terms “state” and “wavefunction” are almost entirely analogous in describing quantum systems – the former describing quantised (previously mentioned, discrete) states and the latter describing a continuous state-distribution (i.e. a function).

Whether the wavefunction exists in reality or is simply a philosophical concept is a topic of debate in quantum theory, with some seeing it as a conceptual property of abstract mathematical space and others seeing it as a physical reality. Regardless of perception, the results of manipulating the wavefunction corroborate well with observations and—since the days of Dirac, Schrödinger and Einstein—the discussion is left more to small-talk at cocktail parties than real scientific debate.


Now we can introduce the basis vector of ψ, denoted by a “bra”

This can represent the conjugate transposition of either the set of states or the continuous wavefunction represented by ψ. In general,

This is known as the co-vector to the state vector | ψ ⟩. For a discrete set of states, the co-vector to | ψ ⟩—the basis vector—is

where * denotes the complex conjugate. This represents the conjugate transpose of the state vector. For a continuous function the basis vector to | ψ ⟩ is

where ψ is, again, a complex function and ψ* is its conjugate.

Alone, these states and basis vectors mean very little about our system. Dirac’s bra-ket notation can be best understood through analysis of the Hilbert space, which we’ll look at next time to examine the intrinsic mathematical properties implied within this notation.

This floor tiling can go on forever in any direction, but never looks quite the same anywhere. It was discovered by English physicist Roger Penrose in the 1970s.

The Physics of Sliding on Ice

by Gabriel Popkin, Inside Science

For a solid material, ice is strangely slippery. While Olympic skiers and children on a snowy hill may or may not care why their favorite winter activities are physically possible, the question has bedeviled scientists for more than a century. Ice is “one of the most complicated” materials, said physicist Bo Persson of Forschungszentrum Jülich in Germany. “It behaves strangely compared to other materials.”

A new study published by Persson in the Journal of Chemical Physics provides a mathematical foundation for hypotheses that a liquid-like form of water on the ice surface accounts for its slickness.

The finding could aid designers of winter sports gear who want to increase sliding on ice, and tire designers who want to minimize it. It could also help experimental scientists who have measured ice friction but have not been able to fully explain their results.

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Hertha Ayrton (1854-1923) was an English inventor, mathematician, physicist, and engineer. Throughout her life she registered 26 patents for inventions, most of them mathematical dividers or arc lamps and electrodes. For her work on electric arcs and sand ripples, she was awarded the Hughes Medal by the Royal Society, the first woman and so far one of the only two to be honoured in this way.

She attended Girton College in Cambridge, but was not awarded a degree on account of her gender. Later, she became the first woman to read a paper before the Royal Society, but was not eligible as a Fellow because of her status as a married woman. She helped found the International Federation of University Women in 1919.

Dyson is an English-American theoretical physicist and mathematician, known for his work in quantum electrodynamics, solid-state physics, astronomy and nuclear engineering. He is also known for his speculative work on extraterrestrial civilizations.

Perspective view of Hooke crater in Argyre basin

Hooke crater is located near the northern edge of the 1800 km-wide Argyre basin, one of the most impressive impact structures on Mars, excavated in a giant collision about 4 billion years ago.

Sitting in a flat part of the basin known as Argyre Planitia, Hooke crater has a diameter of 138 km and a maximum depth of about 2.4 km. It is named after the English physicist and astronomer Robert Hooke (1635–1703).

Hooke crater comprises two different impact structures, with a smaller impactor blasting a depression off-centre in the floor of a larger, pre-existing crater. The newer crater in the centre is filled with a large mound topped by a dark dune field. The mound appears to be composed of layered material, possibly alternating sheets of sand and frost.

Image credits: ESA/DLR/FU Berlin