DOCSLIB.ORG

A Function Space Defined by the Wigner Transform and Is Applications

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A Function Space Defined by the Wigner Transform and Is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Numerical Harmonic Analysis Group A Function Space defined by the Wigner Transform and is Applications Hans G. Feichtinger, Univ. Vienna & TUM [email protected] www.nuhag.eu Eugene Wigner Institute, Budapest . JOINT presentation with Maurice de Gosson Hans G. Feichtinger, Univ. Vienna & TUM [email protected] Function Spacewww.nuhag.eu defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Key aspects of my talk 1 Fourier Analysis is a classical topic 2 Time-Frequency Analysis 3 S L2 S0 d The Banach Gelfand Triple ( 0; ; 0)(R ) 4 Various Typical Applications 5 The Idea of Conceptual Harmonic Analysis Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Starting with my personal background My education at the University of Vienna started as a teacher student in Mathematics and Physics; Soon the \imprecision" in physics combined with the BOURBAKI-style (clear and well structured) introduction into analysis (including Lebesgue integrals and functional analysis) let me go more in the direction of (pure) mathematics; In my third year of studies (1971) my then advisor H. Reiter arrived in Vienna, so I became a \Harmonic Analyst"; After my habilitation (1979) I learned about the connection between Fourier Analysis and signal processing in Heidelberg; Since that time I tried to look out for real world applications and call myself now an application oriented mathematician; One of my recent \hobbies" is to promote what I call Conceptional Harmonic Analysis. Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize A personal background story At some point in the early 80th I tried to connect with the applied people at TU Vienna, and (fortunately) I ended up contacting Franz Hlawatsch (Communication Theory Dept., TU Vienna). During our first meeting he explained to me, that he was working on the so-called Pseudo-Wigner distribution, which is a kind of smoothed version of the Wigner distribution, with the idea of reducing the so-called interference terms in a Wigner distribution. I told him that I was studying a certain function space (I called it S d 0(R ); k · kS0 , because it was a special Segal algebra), given by: S d X X 0(R ) = ff j f = cnM!n Txn g0; with jcnj < 1g; (1) n≥1 n≥1 2 where g0(x) = exp(−πjxj ) is the usual Gauss function. Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize The relevance for my future work At this point none of us had an idea how close we had been in terms of the setting of our research (which was then going on for almost 20 years)! He had two important questions 1 Do you really need all TF-shifts, D. Gabor has suggested to d use only xn;!n 2 Z ! 2 and: How do you compute the coefficients? In fact, according to the claim made in D. Gabor's paper of 1946 [5] one should expect that an optimally centrated representation of any function, using integer TF-shifts of the Gauss function (achieving equality in the Heisenberg Uncertainty Relation!) should be possible. In fact, he only argued that a TF-lattice of the form aZ × bZ with ab > 1 is not comprehensive enough and ab < 1 produces linear dependencies. Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Eugene Wigner Eugene Paul Wigner (November 17, 1902 to January 1, 1995), was a Hungarian-American theoretical physicist, engineer, and mathematician. Nobel Prize in Physics in 1963 for his contributions to the theory of the atomic nucleus and the elementary particles and symmetry principles. Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Dennis Gabor Dennis Gabor (5 June 1900 to 9 February 1979) was a Hungarian-British electrical engineer and physicist, most notable for inventing holography, for which he later received the 1971 Nobel Prize in Physics. Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize S d 0(R ) via the Wigner transform Z d n 1 d o S0(R ) = f 2 L (R ): kM!f ∗ f k1 d! < 1 : (2) R2d Condition (2) is equivalent to the integrability of the Wigner d d functions over phase space R × Rb . 2πi!·t d d Here M!f (t) = e f (t), t 2 R ;! 2 R , is the modulation 1 d operator and ∗ is the usual convolution of L (R )-functions. Any d d non-zero function g 2 S0(R ) defines a norm on S0(R ) via Z kf kS0;g = kE!f ∗ gk1 d!; (3) gb d that turns S0(R ) into a Banach space. These norms are pairwise equivalent and we therefore allow ourselves to simply write k · kS0 without specifying n g (see also [2]). Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize A schematic description: all the spaces Tempered Distr. L1 L2 C0 SO' S0 Schw FL1 Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Banach Gelfand Triples: the simplified setting Testfunctions ⊂ Hilbert space ⊂ Distributions, like Q ⊂ R ⊂ C! Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize The key-players for time-frequency analysis Time-shifts and Frequency shifts Tx f (t) = f (t − x) d and x; !; t 2 R 2πi!·t M!f (t) = e f (t) : Behavior under Fourier transform ^ ^ (Tx f )b= M−x f (M!f )b= T!f The Short-Time Fourier Transform Vg f (λ) = hf ; M!Tt gi = hf ;π (λ)gi = hf ; gλi; λ = (t;!); Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize A Typical Musical STFT A typical waterfall melody (Beethoven piano sonata) depictured using the spectrogram, displaying the energy distribution in the TF = time-frequency plan: Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize A Banach Space of Test Functions (Fei 1979) 2 d d A function in f 2 L (R ) is in the subspace S0(R ) if for some d non-zero g (called the \window") in the Schwartz space S(R ) ZZ kf kS0 := kVg f kL1 = jVg f (x;!)jdxd! < 1: Rd ×Rbd S d The space 0(R ); k · kS0 is a Banach space, for any fixed, d non-zero g 2 S0(R )), and different windows g define the same d space and equivalent norms. Since S0(R ) contains the Schwartz d space S(R ), any Schwartz function is suitable, but also compactly supported functions having an integrable Fourier transform (such as a trapezoidal or triangular function) are suitable. It is convenient to use the Gaussian as a window. Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize M1 S d Basic properties of = 0(R ) Lemma d Let f 2 S0(R ), then the following holds: d d d (1) π(u; η)f 2 S0(R ) for (u; η) 2 R × Rb , and kπ(u; η)f kS0 = kf kS0 . ^ S d ^ (2) f 2 0(R ), and kf kS0 = kf kS0 : S d In fact, 0(R ); k · kS0 is the smallest non-trivial Banach space with this property, and therefore contained in any of the Lp-spaces (and their Fourier images). Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize Various Function Spaces FL1 SINC L2 box S0 L2 FL1 L1 Figure: The usual Lebesgues space, the Fourier algebra, and S d the Segal algebra 0(R ) inside all these spaces Hans G. Feichtinger A Function Space defined by the Wigner Transform and is Applications Introduction History Time-Frequency Analysis FT on SOPRd Kernel Theorem Various MATLAB illustrations Spectrograms bibliography Nobel Prize BANACH GELFAND TRIPLES: a new category Definition A triple, consisting of a Banach space (B; k · kB ), which is densely embedded into some Hilbert space H, which in turn is contained in B0 is called a Banach Gelfand triple. Definition B B0 B B0 If ( 1; H1; 1) and ( 2; H2; 2) are Gelfand triples then a linear operator T is called a [unitary] Gelfand triple isomorphism if 1 A is an isomorphism between B1 and B2.
Load more

Recommended publications
  • A Time of Great Growth
    Newsletter | Spring 2019 A Time of Great Growth Heartfelt greetings from the UC Riverside Department of Physics and Astronomy. This is our annual newsletter, sent out each Spring to stay connected with our former students, retired faculty, and friends in the wider community. The Department continues to grow, not merely in size but also in stature and reputation. For the 2018-2019 academic year, we were pleased to welcome two new faculty: Professors Thomas Kuhlman and Barry Barish. Professor Kuhlman was previously on the faculty at the University of Illinois at Urbana-Champaign. He joins our efforts in the emerging field of biophysics. His research lies in the quantitative imaging and theoretical modeling of biological systems. He works on genome dynamics, quantification of the activity of transposable elements in living cells, and applications to the engineering of genome editing. Professor Barry Barish, who joins us from Caltech, is the winner of the 2017 Nobel Prize in Physics. He brings great prestige to our Department. Along with Professor Richard Schrock of the Department of Chemistry, who also joined UCR in 2018, UCR now has two Nobel Prize winners on its faculty. Professor Barish is an expert on the detection and physics of gravitational waves. He has been one of the key figures in the conception, construction, and operation of the LIGO detector, where gravitational waves were first discovered in 2015, and which led to his Nobel Prize. He is a member of the National Academy of Sciences and the winner of many other prestigious awards. The discovery of gravitational waves is one of the most exciting developments in physics so far this century.
    [Show full text]
  • Ripples in Spacetime
    editorial Ripples in spacetime The 2017 Nobel prize in Physics has been awarded to Rainer Weiss, Barry C. Barish and Kip S. Thorne “for decisive contributions to the LIGO detector and the observation of gravitational waves”. It is, frankly, difficult to find something original to say about the detection of gravitational waves that hasn’t been said already. The technological feat of measuring fluctuations in the fabric of spacetime less than one-thousandth the width of an atomic nucleus is quite simply astonishing. The scientific achievement represented by the confirmation of a century-old prediction by Albert Einstein is unique. And the collaborative effort that made the discovery possible — the Laser Interferometer Gravitational-Wave Observatory (LIGO) — is inspiring. Adapted from Phys. Rev. Lett. 116, 061102 (2016), under Creative Commons Licence. Rainer Weiss and Kip Thorne were, along with the late Ronald Drever, founders of the project that eventually became known Barry Barish, who was the director Last month we received a spectacular as LIGO. In the 1960s, Thorne, a black hole of LIGO from 1997 to 2005, is widely demonstration that talk of a new era expert, had come to believe that his objects of credited with transforming it into a ‘big of gravitational astronomy was no interest should be detectable as gravitational physics’ collaboration, and providing the exaggeration. Cued by detections at LIGO waves. Separately, and inspired by previous organizational structure required to ensure and Virgo, an interferometer based in Pisa, proposals, Weiss came up with the first it worked. Of course, the passion, skill and Italy, more than 70 teams of researchers calculations detailing how an interferometer dedication of the thousand or so scientists working at different telescopes around could be used to detect them in 1972.
    [Show full text]
  • The History of Lasers at Stanford Group
    Lasers at 50: Byer The History of Lasers at Stanford Group Robert L. Byer Applied Physics Stanford University [email protected] Abstract In the fifty years since the demonstration of the laser, coherent light has changed the way we work, communicate and play. The generation and control of light is critical for meeting important challenges of the 21st century from fundamental science to the generation of energy. A look back at the early days of the laser at Stanford will be contrasted to the recent breakthroughs in solid state lasers and the applications to fundamental science of gravitational wave detection, remote sensing, and laser induced fusion for energy production. Stanford Historical Society 34th Annual Meeting & Reception May 25, 2010 The History of Lasers at Stanford May 25 2010 Cubberley Auditorium, Staford Byer California – Leader in advanced telescopes for astronomy Group Lick 36 inch refractor The Mount Wilson 100 inch The Palomar 200 inch 1888 1917 1948 The History of Lasers at Stanford May 25 2010 Cubberley Auditorium, Staford From Maser to Laser – stimulated emission at optical frequencies Byer proposed in 1958 – A. Schawlow and C. H. Townes Group The History of Lasers at Stanford May 25 2010 Cubberley Auditorium, Staford Early advances in lasers --- Byer 2009 a Special Year Group Concept of Optical Maser Schawlow & Townes 1958 Ruby Laser Ted Maiman 1960 Nobel Prize awarded in 1964 Townes, Prokhorov and Basov Hg+ Ion Laser Earl Bell 1965 Argon Ion Laser Bill Bridges Tunable cw parametric Laser Harris 1968 Diode bar 1Watt
    [Show full text]
  • Rainer Weiss, Professor of Physics Emeritus and 2017 Nobel Laureate
    Giving to the Department of Physics by Erin McGrath RAINER WEISS ’55, PHD ’62 Bryce Vickmark Rai Weiss has established a fellowship in the Physics Department because he is eternally grateful to his advisor, the late Jerrold Zacharias, for all that he did for Rai, so he knows firsthand the importance of supporting graduate students. Rainer Weiss, Professor of Physics Emeritus and 2017 Nobel Laureate. Rainer “Rai” Weiss was born in Berlin, Germany in 1932. His father was a physician and his mother was an actress. His family was forced out of Germany by the Nazis since his father was Jewish and a Communist. Rai, his mother and father fled to Prague, Czecho- slovakia. In 1937 a sister was born in Prague. In 1938, after Chamberlain appeased Hitler by effectively giving him Czechoslovakia, the family was able to obtain visas to enter the United States through the Stix Family in St. Louis, who were giving bond to professional Jewish emigrants. When Rai was 21 years-old, he visited Mrs. Stix and thanked her for what she had done for his family. The family immigrated to New York City. Rai’s father had a hard time passing the medi- cal boards because of his inability to answer multiple choice exams. His mother, who Rai says “held the family together,” worked in a number of retail stores. Through the services of an immigrant relief organization Rai received a scholarship to attend the prestigious Columbia Grammar School. At the end of 1945, when Rai was 13 years old, he became fascinated with electronics and music.
    [Show full text]
  • A Joint Fermilab/SLAC Publication Dimensions of Particle Physics Issue
    dimensions volume 03 of particle physics symmetryA joint Fermilab/SLAC publication issue 05 june/july 06 Cover Physicists at Fermilab ponder the physics of the proposed International Linear Collider, as outlined in the report Discovering the Quantum Universe. Photos: Reidar Hahn, Fermilab Office of Science U.S. Department of Energy volume 03 | issue 05 | june/july 06 symmetryA joint Fermilab/SLAC publication 3 Commentary: John Beacom “In a global fi eld, keeping up with all the literature is impossible. Personal contact is essential, and I always urge students and postdocs to go to meetings and talk to strangers.” 4 Signal to Background An industrial waterfall; education by placemats; a super-clean surface; horned owls; Garden Club for particle physicists; Nobel banners; US Congress meets Quantum Universe. 8 Voices: Milestones vs. History Celebrating a milestone is always enjoyable, but a complete and accurate historical record is invalu- able for the past to inform the future. 10 A Report Like No Other Can the unique EPP2010 panel steer US particle physics away from a looming crisis? Physicists and policy makers are depending on it. 14 SNS: Neutrons for ‘molecular movies’ A new research facility at Oak Ridge National Laboratory has produced its fi rst neutrons, presenting new opportunities for studying materials from semiconductors to human enzymes. 20 Battling the Clouds Electron clouds could reduce the brightness—and discovery potential—of the proposed International Linear Collider. Innovative solutions are on the way and might reduce the cost of the machine, too. 24 A (Magnus) Force on the Mound Professional baseball player Jeff Francis of the Colorado Rockies brings a strong arm and a physics background to the playing fi eld: “I bet Einstein couldn’t throw a curveball.” 26 Deconstruction: Spallation Neutron Source Accelerator-based neutron sources such as the SNS can provide pulses of neutrons to probe superconductors, aluminum bridges, lighter and stronger plastic products, and pharmaceuticals.
    [Show full text]
  • The Strong and Weak Senses of Theory-Ladenness of Experimentation: Theory-Driven Versus Exploratory Experiments in the History of High-Energy Particle Physics
    [Accepted for Publication in Science in Context] The Strong and Weak Senses of Theory-Ladenness of Experimentation: Theory-Driven versus Exploratory Experiments in the History of High-Energy Particle Physics Koray Karaca University of Wuppertal Interdisciplinary Centre for Science and Technology Studies (IZWT) University of Wuppertal Gaußstr. 20 42119 Wuppertal, Germany [email protected] Argument In the theory-dominated view of scientific experimentation, all relations of theory and experiment are taken on a par; namely, that experiments are performed solely to ascertain the conclusions of scientific theories. As a result, different aspects of experimentation and of the relation of theory to experiment remain undifferentiated. This in turn fosters a notion of theory- ladenness of experimentation (TLE) that is too coarse-grained to accurately describe the relations of theory and experiment in scientific practice. By contrast, in this article, I suggest that TLE should be understood as an umbrella concept that has different senses. To this end, I introduce a three-fold distinction among the theories of high-energy particle physics (HEP) as background theories, model theories and phenomenological models. Drawing on this categorization, I contrast two types of experimentation, namely, “theory-driven” and “exploratory” experiments, and I distinguish between the “weak” and “strong” senses of TLE in the context of scattering experiments from the history of HEP. This distinction enables to identify the exploratory character of the deep-inelastic electron-proton scattering experiments— performed at the Stanford Linear Accelerator Center (SLAC) between the years 1967 and 1973—thereby shedding light on a crucial phase of the history of HEP, namely, the discovery of “scaling”, which was the decisive step towards the construction of quantum chromo-dynamics (QCD) as a gauge theory of strong interactions.
    [Show full text]
  • Members Elect Barry Barish As Next APS Vice-President
    October 2008 Volume 17, No. 9 www.aps.org/publications/apsnews 21st Century Campaign Nears Goal APS NEWS and Needs Your Support! A PublicAtion of the AmericAn PhysicAl society • www.APs.org/PublicAtions/APsnews (See insert) Energy Efficiency Crucial to Achieving Energy Security Members Elect Barry Barish and Reducing Global Warming, States APS Report as next APS Vice-President Tapping wasted energy from miles per gallon mileage for cars needs because they require sig- APS members have elected in physics from the University of inefficient automobiles, homes and and other light-duty vehicles by nificant scientific and engineering Barry Barish, Linde Professor of California, Berkeley. He joined businesses is equivalent to discov- 2030 and the elimination of energy breakthroughs in several critical Physics Emeritus at Caltech, as the faculty at Caltech in 1963. ering a hidden energy reserve that from fossil fuels in new residential areas. the Society’s next vice president. Among his noteworthy experi- will help the United States improve buildings by 2020. The study also calls on Congress Barish will assume the office in ments were those performed at its energy security and reduce glob- and the White House to increase January 2009. At the same time, Fermilab using high-energy neu- al warming, an APS study panel has spending on research and develop- Curtis Callan of trino collisions to concluded. ment of next-generation building Princeton Univer- reveal the quark Their report, Energy Future: technologies, training scientists sity will become substructure of Think Efficiency, states that the key who work on building technologies president-elect, and the nucleon.
    [Show full text]
  • Laser Interferometry Gravitational Wave Detection
    Quantum Noise Limited Lasers and Byer The Search for Gravitational Waves Group Robert L. Byer Department of Applied Physics Stanford University Abstract Einstein formulated the general theory of relativity near 100 years ago and showed that gravity is curvature in space-time and further that ripples in space-time, gravitational waves, travel at the speed of light. Today the Laser Interferometer Gravitational Wave Observatory, LIGO, project is using ground based 4km long interferometers to search for gravitational waves. The progress for LIGO and other earth based gravitational wave interferometers will be reviewed. This summer the Laser Interferometer in Space Antenna, LISA, project, joint between NASA and ESA, will hold its 8th International meeting at Stanford. The design of the space-based 5 million kilometer path length LISA interferometer, scheduled for launch in 2020, will be discussed. The detection of gravitational waves requires the ultimate in precision measurement. The ‘ruler’ used to detect oscillations in space-time is the constant; the speed of light. The light source is a very stable diode-pumped Nd:YAG solid state laser oscillator-amplifier that operates reliably at the quantum limit in phase and amplitude. AAAS 2010 Annual Meeting San Diego, CA February 21, 2010 AAAS 2010 Annual Meeting February 21, 2010 Extreme Optical Tools and Applications Outline Byer Group Prelude: California – a leader in science and technology LIGO & LISA: Early History and Concepts LIGO and LISA at the beginning Gravitational Waves and Sources
    [Show full text]
  • KITCHEN CHEMISTRY Bijeta Roynath & Prasanta Kumar Sahoo
    Test Your Knowledge KITCHEN CHEMISTRY Bijeta Roynath & Prasanta Kumar Sahoo 1. The common cooking fuel, Liquefied Petroleum Gas 10. Which of the following could be produced by the gas (LPG), is a mixture of two hydrocarbons. These are: stove? (a) Methane and Butane (b) Propane and Butane (a) Nitrogen Oxides (b) Sulphur dioxides (c) Oxygen and Hydrogen (d) Hexane and Propane (c) Carbon monoxide (d) Dihydrogen oxide 2. Hydrocarbons in LPG are colourless and odourless. 11. Which of the following chemical is found in dish- Therefore, a strong smelling agent added to LPG washing detergent? cylinders to detect leakage is: (a) Carbon monoxide (b) Chlorine (a) Ethyl mercaptan (b) Nitrous oxide (c) Sulphur dioxide (d) Lithium (c) Hydrogen sulfide (d) Chloroform 12. Proteins help build our body and carbohydrates 3. Chemical irritant produced during chopping an provide energy to the body. The protein and onion (Allium cepa) which makes our eye weepy is: carbohydrate found in milk are: (a) Allinase (b) Sulfoxide (a) Albumin and maltose (b) Pepsin and sucrose (c) Syn-propanethial-S-oxide (d) Allyl mercaptan (c) Collagen and fructose (d) Casein and lactose 4. The powerful anti-inflammatory and antioxidant 13. Salt readily absorbs water from the surroundings. properties of haldi or turmeric (Curcuma longa) are Sprinkling salt on salad releases water from it after due to presence of: few seconds. The process is: (a) Curcumin (b) Gingerol (a) Osmosis (b) Adsorption (c) Cymene (d) Capsaicin (c) Dehydration (d) Oxidation 5. The active ingredient in chilli peppers (Capsicum) 14. Washing hands before eating prevents illness which produces heat and burning sensation in the by killing germs.
    [Show full text]
  • APS News July 2018, Vol. 27. No. 7
    July 2018 • Vol. 27, No. 7 A PUBLICATION OF THE AMERICAN PHYSICAL SOCIETY Homer Neal 1942-2018 Page 3 APS.ORG/APSNEWS Update on the APS Strategic Plan Throughout 2018, APS mem- bers, leadership, and staff have been preparing a new Strategic Plan to guide the Society in coming years (see APS News, February 2018). Archiving Knowledge about Physics Teaching MISSION VALUES VISION The process began in early 2018 at By Charles Henderson and Paula Heron the APS Leadership Convocation Do laboratory experiments help at the founding and develop- when elected leaders of mem- students learn concepts? Why do ment of Physical Review Physics bership units (Divisions, Topical so few women choose to major in Education Research in 2005, now Groups, Forums, and Sections) pro- physics? What is the most impor- a central and open-access home for vided input. Town hall meetings tant skill for a high school physics this work. and invited focus groups convened teacher to develop? The close connection between at the APS March and April meet- and Increasing Organizational Physics education researchers PER and physics as a discipline ings to gather direct member com- Excellence. tackle these and many other ques- was acknowledged by the American ment. CEO Kate Kirby provided an At its June retreat, the Board tions about why students study Physical Society Council in its update at the annual APS Business spent considerable time discuss- physics, what they learn, and 1999 Statement on Research in common teaching strategies and Meeting on April 13 and a member ing progress on the Plan. In guid- how their experiences affect their Physics Education [1].
    [Show full text]
  • Barry C Barish
    Barry C Barish Barry Barish earned his B.A. in physics (1957) and Ph.D. in experimental particle physics (1962) at the University of California, Berkeley. He came to Caltech as a postdoc in 1963, where he has pursued his academic and research careers and is currently the Maxine and Ronald Linde Professor of Physics, Emeritus. Barish’s primary research interest has been the Laser Interferometer Gravitational-wave Observatory (LIGO), since he became Principal Investigator in 1994 and Director in 1997. He led the effort through the final design stages, approval for funding by the NSF National Science Board in 1994, and then the construction and commissioning of the LIGO interferometers in Livingston, LA and Hanford, WA. In 1997, he created the LIGO Scientific Collaboration (LSC), which now enables more than 1000 collaborators world-wide to participate in LIGO. Suspended mass laser interferometers search for gravitational wave signals by monitoring motions of test masses separated by four kilometer baselines to a precision of less than 10–18 meters. The Initial LIGO detectors reached design sensitivity and set many significant limits on astrophysical sources of gravitational waves. A proposal for a more sensitive detector, Advanced LIGO, was developed from 1999 to 2003, while Barish was Director, and it was approved by the NSF in 2003. Advanced LIGO was funded as a major research project (MREFC) by Congress several years later. This project incorporated major new technological developments from the LIGO R&D efforts, including an active seismic isolation system to reduce seismic noise, a multiple suspension system with a large fused silica test mass to reduce thermal noise and a 200 watt NiYAG laser to reduce shot noise, as well as incorporate improved and a more flexible optics system.
    [Show full text]
  • Stefan W. Ballmer
    Stefan W. Ballmer Curriculum Vitae Department of Physics Phone: +1-315-443-3882 Syracuse University Cell: +1-315-278-1154 Syracuse, NY 13244 Fax: +1-315-443-9103 USA E-mail: [email protected] Citizenship: USA, Switzerland Web: thecollege.syr.edu/people/faculty/ballmer-stefan RECENT AND CURRENT POSITIONS Jun 2016 - Associate Professor of Physics present Syracuse University, Syracuse, NY May 2019 - Visiting Associate Professor of Physics Jun 2019 Institute for Cosmic Ray Research, University of Tokyo, Japan May 2018 - Visiting Associate Professor of Physics Jun 2018 Institute for Cosmic Ray Research, University of Tokyo, Japan May 2017 - Visiting Associate Professor of Physics Jun 2017 University of Tokyo, Japan Jun 2013 - Research leave at the LIGO Hanford Observatory Aug 2014 Commissioning the Advanced LIGO interferometer Aug 2010 - Assistant Professor of Physics May 2016 Syracuse University, Syracuse, NY Dec 2009 - NAOJ Visiting Researcher Aug 2010 National Astronomical Observatory of Japan. Sep 2009 - JSPS Postdoctoral Fellow (Gaikokujin Tokubetsu Kenkyuin) Nov 2009 National Astronomical Observatory of Japan. Jul 2006 - Robert A. Millikan Postdoctoral Fellow Aug 2009 California Institute of Technology, Pasadena, CA EDUCATION Jun 2006 Ph.D. Physics, Massachusetts Institute of Technology (MIT), Cambridge, MA Experimental Astrophysics, Laser Interferometer Gravitational Wave Observatory (LIGO). Apr 2000 Diploma (equivalent to Master of Science), Physics, Swiss Federal Institute of Technology (ETH) Zurich, Switzerland With honor, in Theoretical
    [Show full text]