Peter James Lu,

PhD PHD or PhD may refer to: * Doctor of Philosophy (PhD), an academic qualification Entertainment * '' PhD: Phantasy Degree'', a Korean comic series * ''Piled Higher and Deeper'', a web comic * Ph.D. (band), a 1980s British group ** Ph.D. (Ph.D. albu ...

(陸述義) is a post-doctoral research fellow in the Department of Physics and the School of Engineering and Applied Sciences at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

Cambridge Cambridge ( ) is a university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cambridge bec ...

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

. He has been recognized for his discoveries of

quasicrystal A quasiperiodic crystal, or quasicrystal, is a structure that is ordered but not periodic. A quasicrystalline pattern can continuously fill all available space, but it lacks translational symmetry. While crystals, according to the classical cr ...

patterns (

girih tiles ''Girih'' tiles are a set of five tiles that were used in the creation of Islamic geometric patterns using strapwork (''girih'') for decoration of buildings in Islamic architecture. They have been used since about the year 1200 and their arrange ...

) in medieval

Islamic architecture Islamic architecture comprises the architectural styles of buildings associated with Islam. It encompasses both secular and religious styles from the early history of Islam to the present day. The Islamic world encompasses a wide geographic ar ...

, early precision compound machines in ancient China, and man's first use of

diamond Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the Chemical stability, chemically stable form of car ...

neolithic The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts ...

China.

Early life and education

Lu was born in

Cleveland Cleveland ( ), officially the City of Cleveland, is a city in the U.S. state of Ohio and the county seat of Cuyahoga County. Located in the northeastern part of the state, it is situated along the southern shore of Lake Erie, across the U.S. ...

Ohio Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...

and grew up in the Philadelphia suburb of

West Chester, Pennsylvania West Chester is a borough and the county seat of Chester County, Pennsylvania. Located within the Philadelphia metropolitan area, the borough had a population of 18,461 at the 2010 census. West Chester is the mailing address for most of its neighb ...

. His early childhood interest in

rockhounding Amateur geology or rock collecting (also referred to as rockhounding in the United States and Canada) is the non-professional study and hobby of collecting rocks and minerals or fossil specimens from the natural environment.Sinkankas, John. Minera ...

led to his winning national gold medals in the "Rocks, Minerals, and Fossils" event at four National Science Olympiad tournaments. Lu graduated from B. Reed Henderson high school in West Chester in 1996. Lu matriculated at

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

in September, 1996, and was advised in his first year by geology professor

Kenneth S. Deffeyes Kenneth S. Deffeyes was a geologist who worked with M. King Hubbert, the creator of the Hubbert peak theory, at the Shell Oil Company research laboratory in Houston, Texas. He claimed Chickasaw ancestry.Maitland Jones, Jr., with whom Lu published his first paper on his freshman summer research project about

carbenes In organic chemistry, a carbene is a molecule containing a neutral carbon atom with a valence of two and two unshared valence electrons. The general formula is or where the R represents substituents or hydrogen atoms. The term "carbene" m ...

. As an undergraduate physics major, he wrote his fourth-year senior thesis with Prof. Paul J. Steinhardt on the search for natural

quasicrystals A quasiperiodic crystal, or quasicrystal, is a structure that is ordered but not periodic. A quasicrystalline pattern can continuously fill all available space, but it lacks translational symmetry. While crystals, according to the classical cr ...

, later published in ''

Physical Review Letters ''Physical Review Letters'' (''PRL''), established in 1958, is a peer-reviewed, scientific journal that is published 52 times per year by the American Physical Society. As also confirmed by various measurement standards, which include the ''Journa ...

''. Lu graduated summa cum laude and

Phi Beta Kappa The Phi Beta Kappa Society () is the oldest academic honor society in the United States, and the most prestigious, due in part to its long history and academic selectivity. Phi Beta Kappa aims to promote and advocate excellence in the liberal a ...

with an A.B. in physics from Princeton in June, 2000. In September, 2000, he began his graduate studies at

, receiving an A. M. in physics in 2002. In 2005, Lu presented a set of lectures in Turkmenistan. Since 2007, Lu has served on the national advisory committee of the

Science Olympiad Science Olympiad is an American team competition in which students compete in 23 events pertaining to various fields of science, including earth science, biology, chemistry, physics, and engineering. Over 7,800 middle school and high school team ...

. Lu completed his Ph.D. in physics in 2008.

Girih tiles and quasicrystals in medieval Islamic architecture

Lu's most widely publicized work involves his discovery of the

, a set of fundamental geometric tiles used to create a wide range of patterns in medieval Islamic architecture. In collaboration with

Paul Steinhardt Paul Joseph Steinhardt (born December 25, 1952) is an American theoretical physicist whose principal research is in cosmology and condensed matter physics. He is currently the Albert Einstein Professor in Science at Princeton University, where he ...

, he demonstrated their use to create

tilings on the walls of

Darb-i Imam The shrine of Darb-e Imam ( fa, امامزاده درب امام), located in the Dardasht quarter of Isfahan, Iran, is a funerary complex, with a cemetery, shrine structures, and courtyards belonging to different construction periods and styles. ...

shrine (1453 A.D.) in

Isfahan Isfahan ( fa, اصفهان, Esfahân ), from its Achaemenid empire, ancient designation ''Aspadana'' and, later, ''Spahan'' in Sassanian Empire, middle Persian, rendered in English as ''Ispahan'', is a major city in the Greater Isfahan Regio ...

Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...

. The finding was considered a significant breakthrough by demonstrating a simple and straightforward method that could have been used by common workers to create extremely complicated patterns using

, and by identifying a medieval example of

line patterns, which were not widely known to or understood by the West until the discovery of

Penrose tiling A Penrose tiling is an example of an aperiodic tiling. Here, a ''tiling'' is a covering of the plane by non-overlapping polygons or other shapes, and ''aperiodic'' means that shifting any tiling with these shapes by any finite distance, without r ...

s by

Roger Penrose Sir Roger Penrose (born 8 August 1931) is an English mathematician, mathematical physicist, philosopher of science and Nobel Laureate in Physics. He is Emeritus Rouse Ball Professor of Mathematics in the University of Oxford, an emeritus fello ...

in the 1970s. For its timely scientific and political implications, Lu and Steinhardt's work on medieval Islamic architectural tilings received substantial worldwide coverage on the front pages of a number of major newspapers, on the radio, and in magazines; the finding was identified as among the top 100 scientific discoveries of 2007 by ''Discover'' magazine.

Technology in ancient Chinese art

Earliest precision compound machines

In 2004, Lu presented evidence in a single-author paper in

Science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

that ancient Chinese craftsmen during the

Spring and Autumn period The Spring and Autumn period was a period in Chinese history from approximately 770 to 476 BC (or according to some authorities until 403 BC) which corresponds roughly to the first half of the Eastern Zhou period. The period's name derives fr ...

used precision compound machines to craft spiral grooves on

Chinese jade Chinese jade refers to the jade mined or carved in China from the Neolithic onward. It is the primary hardstone of Chinese sculpture. Although deep and bright green jadeite is better known in Europe, for most of China's history, jade has come i ...

burial rings; Lu had been introduced earlier to the grooved rings by Prof. Jenny So at the Smithsonian Institution. Lu discovered that these grooves follow the exact mathematical form of the

Archimedes spiral The Archimedean spiral (also known as the arithmetic spiral) is a spiral named after the 3rd-century BC Greek mathematician Archimedes. It is the locus corresponding to the locations over time of a point moving away from a fixed point with a con ...

, demonstrating the ability of ancient craftsmen to interconvert two types of motion precisely, in order to fashion the jade rings. The close conformity to this mathematical form confirmed that these craftsmen must have had a precision compound machine (as opposed to a

simple machine A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refer ...

) in 550 BC, predating Archimedes by several centuries; prior to this paper, the earliest compound machines were thought to be of Greek origin (e.g.,

Archimedes' screw The Archimedes screw, also known as the Archimedean screw, hydrodynamic screw, water screw or Egyptian screw, is one of the earliest hydraulic machines. Using Archimedes screws as water pumps (Archimedes screw pump (ASP) or screw pump) dates back ...

). Lu's discovery of the earliest precision compound machines was included in the ''Encyclopædia Britannica''.

Man's first use of diamond

Lu continued his interdisciplinary combination of art history and physics with his discovery, with a group of collaborators, of man's first use of diamond, in

China. Prior to this work, evidence for man's first use of

was known primarily from Indian texts dating to the latter half of the first millennium BC, and there was no reported evidence for its use in prehistoric times. In 2005, Lu and collaborators reported strong evidence that the ancient Chinese used diamonds to polish ceremonial stone burial axes as early as 2500 BC, placing the earliest known use of diamond two thousand years before the mineral is known to have been used elsewhere. These stone axes, made predominantly of the mineral corundum (sapphire and ruby in its colorful gem forms) were fashioned as early as 4000 BC, so that they represent the earliest use of the mineral

corundum Corundum is a crystalline form of aluminium oxide () typically containing traces of iron, titanium, vanadium and chromium. It is a rock-forming mineral. It is a naturally transparent material, but can have different colors depending on the pres ...

, as well. The finding's media coverage included a front-page article in China's largest English-language newspaper, the

China Daily ''China Daily'' () is an English-language daily newspaper owned by the Central Propaganda Department of the Chinese Communist Party. Overview ''China Daily'' has the widest print circulation of any English-language newspaper in China. T ...

Other contributions

Lu's interests in geology-related phenomena also include

paleontology Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

, which led to collaboration with his college and grad-school roommate Motohiro Yogo and Prof. Charles Marshall. Leveraging vector autoregression analysis upon an established marine fossil record, Lu, Yogo and Marshall found that a "speed limit", which was previously thought to restrict the reemergence of biodiversity following a mass extinction, may be an artifact of the incompleteness of the fossil record. According to paleontologist

Douglas Erwin Douglas Erwin is a paleobiologist, Curator of Paleozoic Invertebrates at the Smithsonian National Museum of Natural History and Chair of the Faculty at the Santa Fe Institute. He is a member of the Editorial Board for ''Current Biology ''Curre ...

of the

National Museum of Natural History The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. In 2021, with 7 ...

in Washington, D.C., "This is the battle line for the next decade in paleontology." Lu's research in the group of Prof.

David A. Weitz David A. Weitz (born October 3, 1951) is a Canadian/American physicist and Mallinckrodt Professor of Physics & Applied Physics at Harvard University. He is the former co-director of the BASF Advanced Research Initiative at Harvard, former co-dire ...

focused on the behavior of attractive colloidal particles in the laboratory and in the microgravity environment of the

International Space Station The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...

. In 2008, Lu, Weitz and collaborators in Rome combined experiment and computer simulations to demonstrate that the onset of colloidal gelation is triggered by a form of phase separation known as spinodal decomposition, resolving a long-standing debate within the soft condensed-matter physics community on the origins of this mechanism. Lu's colloid work has also led to the development of new techniques for observing real-time, three-dimensional behavior of colloidal particles, and freely-moving biological cells, with active target-locking in real-time confocal microscopy. Lu also wrote the opening chapter, on confocal microscopy and nanotechnology, of the ''Handbook of Microscopy for Nanotechnology'', edited by Nan Yao.

Notes

External links

Peter J. Lu's home page
{{DEFAULTSORT:Lu, Peter 1978 births Living people Scientists from Cleveland 21st-century American physicists Harvard University faculty Harvard University alumni Princeton University alumni