Alumni of Note

Key Player - Maryland Stadium Authority\u27s Alison Asti; Big Hitters: Percival\u27s Winning Softball Team; Fitting Tributes: Newly Endowed Scholarships

From quantum stochastic differential equations to Gisin-Percival state diffusion

Starting from the quantum stochastic differential equations of Hudson and Parthasarathy (Comm. Math. Phys. 93, 301 (1984)) and exploiting the Wiener-Ito-Segal isomorphism between the Boson Fock reservoir space $\Gamma(L^2(\mathbb{R}_+)\otimes (\mathbb{C}^{n}\oplus \mathbb{C}^{n}))$ and the Hilbert space $L^2(\mu)$, where $\mu$ is the Wiener probability measure of a complex $n$-dimensional vector-valued standard Brownian motion $\{\mathbf{B}(t), t\geq 0\}$, we derive a non-linear stochastic Schrodinger equation describing a classical diffusion of states of a quantum system, driven by the Brownian motion $\mathbf{B}$. Changing this Brownian motion by an appropriate Girsanov transformation, we arrive at the Gisin-Percival state diffusion equation (J. Phys. A, 167, 315 (1992)). This approach also yields an explicit solution of the Gisin-Percival equation, in terms of the Hudson-Parthasarathy unitary process and a radomized Weyl displacement process. Irreversible dynamics of system density operators described by the well-known Gorini-Kossakowski-Sudarshan-Lindblad master equation is unraveled by coarse-graining over the Gisin-Percival quantum state trajectories.Comment: 28 pages, one pdf figure. An error in the multiplying factor in Eq. (102) corrected. To appear in Journal of Mathematical Physic

Metamorphic fluids and uplift-erosion history of a portion of the Kapuskasing structural zone, Ontario, as deduced from fluid inclusions

Fluid inclusions can be used to determine the compositional evolution of fluids present in high grade metamorphic rocks (Touret, 1979) along with the general P-T path followed by the rocks during uplift and erosion (Hollister et al., 1979). In this context, samples of high grade gneisses from the Kapuskasing structural zone (KSZ, Fig. 1) of eastern Ontario were studied in an attempt to define the composition of syn- and post-metamorphic fluids and help constrain the uplift and erosion history of the KSZ. Recent work by Percival (1980), Percival and Card (1983) and Percival and Krogh (1983) shows that the KSZ represents lower crustal granulites that form the lower portion of an oblique cross section through the Archean crust, which was up faulted along a northeast striking thrust fault. The present fluid inclusion study places constraints upon the P-T path which the KSZ followed during uplift and erosion

Structural studies on algal polysaccharides

1. The Hydrolysis of 3-p-Toluenesulphonyl Derivatives of Galactose By E.E.Percival and E.G.V. Percival. J.Chem.Soc., 1938,1585. • 2. Carbohydrate Phosphoric Esters. Pt.I. The Alkaline Hydrolysis of α-Methylglucopyrano-side-6-phosphate, Methylglucofuranoside-3- phosphates and isoPropylideneglucofuranose-3- and -6- phosphates By E.E.Percival and E.G.V. Percival. J.Chem.Soc., 1945, 874. • 3. 3:4- Dimethyl L- Fucose and 2:3- Dimethyl L-Rhamnose By E.E.Percival and E.G.V.Percival. J.Chem.Soc., 1950, 690. • 4. Crystalline 2:3-Dimethyl α-D-Xylose By S.K. Chanda, E.E.Percival and (the Late) E.G.V. Percival. J.Chem.Soc., 1952, 260. • 5. Synthesis of 3:4- and 3:5-Dimethyl Xylose. By E.E.Percival and Rolf Zobrist. J.Chem.Soc., 1952,4306. • 6. The Preparation of 2:3-Anhydromethyl-D-lyxoside from 2-Toluene-p-sulphonyl Methyl-D-xylofuranoside, and Synthesis of 2-Methyl-D-xylose, 3-Methyl-D-arabinose, and 3:5-Dimethyl-D-arabinose by E.E.Percival and Rolf Zobrist. J.Chem.Soc., 1953, 564. • 7. Synthesis of 2-0-Methyl-and 3:4-D1-0-methyl-D-galacturonic acid By R.A.Edington and Elizabeth Percival. J.Chem.Soc., 1953,2473. • 8. Syntheses of Methyl Ethers of Fructose By E. L. Hirst, W.E.A.Mitchell, Elizabeth E.Percival and(the late) E.G.V.Percival. J.Chem.Soc., 1953,3170. • 9. The Periodate Oxidation of Methylfructoses. By W.E.A.Mitchell and Elizabeth Percival. J.Chem.Soc., 1954,1423. • 10. Products from the Alkaline and Reductive Fission of the Epoxide Ring of Methyl 3:4- and 2:3-Anhydro-6-deoxy-α-L-taloside and of their Methylated Derivatives. By George Charalambous and Elizabeth Percival. J.Chem.Soc.,1954,2443. • 11. Glucosamine 6- Phosphate by J.M.Anderson and Elizabeth Percival. Chem. and Ind. ,1954,1018. • 12. The Mercaptolysis of the Polysaccharide from Chondrus crispus by Elizabeth E. Percival. Chem. and Ind.,1954 1487. • 13. The Ammonolysis of Methyl 2:3-Anhydro-D-lyxofuranoside by J.M.Anderson and Elizabeth Percival. J.Chem.Soc., 1955,1042. • 14. The Synthesis of Methyl Ethers of Mannuronic and Glucuronic acid, and their Reaction with Periodate by R.A.Edington, E.L.Hirst and Elizabeth E. Percival. J.Chem.Soc., 1955,2281. • 15. Water Soluble Polysaccharides of Cladophora rupestris By I.S.Fisher and E.E.Percival (read by E.E.Percival). Paper read at the Internat. Seaweed Sym. Norway,1955. • 16. Paper Chromatography of Uronic Acids By R.A.Edington and Elizabeth Percival • 17. The Synthesis of Glucosamine 6- (Dihydrogen Phosphate) By J.M.hnderson and Elizabeth Percival. J.Chem.Soc., 1955, 3554. • 18. The Ammonolysis of Methyl 2:3-Anhydro-D-furanosides. Pt.II. Methyl 2:3-Anhydro-5-0-methyl-α- and -ß- lyxofuranosides. By J.M. Anderson and Elizabeth Percival. J.Chem.Soc., 1956,819. • 19. Methylene Derivatives of L-Fucose By R.L. Nelson and Elizabeth Percival. J.Chem.Soc., 1957, 2191. • 20. The Water-soluble Polysaccharides of Cladophora rupestris. By I.S.Fisher and Elizabeth Percival. • 21. Methyl Ethers of L-Fucose By J.G.Gardiner and Elizabeth Percival. J.Chem.Soc., 1958,1414. • 22. The Structure of Brachychiton diversifolium J.Chem.Soc., Gum (Sterculia caudata). By E.L. Hirst, Elizabeth Percival and R.S.Williams. J.Chem.Soc., 1958,1942. • 23. Barry Degradation of Laminarin By E.L.Hirst J.J.O'Donnell and Elizabeth Percival. Chem. & Ind., 1958, 834. • 24. The Presence of L-Guluronic Acid Residues in Alginic Acid By D.W.Drummond, E.L.Hirst and Elizabeth Percival. Chem. & Ind., 1958,1088. • 25. The Polysaccharides of Acrosiphonia centralis (Spongomorpha arcta) By J.J.O'Donnell and read Intern. Elizabeth Percival. Abs. Paper read Intern. Sym.Seaweed Galway,1958. • 26. Analysis of the Carbohydrates of Cladostephus sp. By R.S.Fanshawe and Elizabeth Percival. J.Sci.Food and Agri. 1958,241. • 27. The Constitution of Xylan from the Green Seaweed Caulerpa filiformis. By I.M.Mackie and 1959,1151 Elizabeth Percival. J.Chem.Soc.,1959, 1151. • 28. The Water -soluble Polysaccharides of Cladophora rupestris. Pt.II. Barry Degradation and Methylation of the Degraded Polysaccharide By J.J.O'Donnell and Elizabeth Percival. J.Chem.Soc., 1959,1739. • 29. Structural Investigations on the Water-soluble Polysaccharides from the Green Seaweed Acrosiphonia centralis (Spongomorpha arcta) By J.J.O'Donnell and Elizabeth Percival. J.Chem.Soc., 1959,2168. • 30. Ultraviolet Spectra and Periodate Oxidation of Monosaccharide Phenylhydrazones By J.J. O'Donnell and Elizabeth Percival. J.Chem.Soc., 1959,2312. • 31. Polysaccharides from the Green Seaweed Caulerpa filiformis. Pt. II. An Amylopectin-type Glucan By I.M.Mackie and Elizabeth Percival. (In the press)

Robert V. Percival: Environmental Crusader

Professor Robert V. Percival wrote the book on environmental law and he\u27s out to save the world by educating the next generation of environmental lawyers

Recent advances in the biology and treatment of certain fungus diseases of the skin

(a) THESIS - Recent Advances in the Biology and Treatment of Certain Fungus Diseases of the Skin. (b) Seven published papers on dermatological problems: (1) The calcium content of the blood serum in skin diseases. G.H. Percival and C.P. Stewart. Brit. J. Derm. Syph. 1927, 39, 144. (2) Some observations on a condition of chronic erythema of the legs. G.H. Percival and C.P. Stewart. Ibid. 39, 115. (3) Melanogenesis: a review. G.H. Percival and C.P. Stewart. Ed. Med. J. Sept. 1930. (4) Observations on the aetiology of erythema exudativum multiforme. G.H. Percival and H.J. Gibson. Brit. J. Derm. Syph. 1931, 43, 329. (5) A study of the skin vessels in some forms of inflammation of the skin. G.H. Percival and C.P.I. Scott. J. Pharm. Exper. Therap. 1931, 41, 147. (6) On the sulphydryl - containing constituent of the epidermis and its relationship to melanogenesis and keratinization. G.H. fμ o) Percival and C.P. Stewart. Brit. J. Derm. Syph. 1930, 42, 215. (7) Experimental Qba,ervations on Der at' d to Dyed Fur. u.n.Percival. Lancet. X1 51, p.41 /

Generalized quantum measurement

We overcome one of Bell's objections to `quantum measurement' by generalizing the definition to include systems outside the laboratory. According to this definition a {\sl generalized quantum measurement} takes place when the value of a classical variable is influenced significantly by an earlier state of a quantum system. A generalized quantum measurement can then take place in equilibrium systems, provided the classical motion is chaotic. This paper deals with this classical aspect of quantum measurement, assuming that the Heisenberg cut between the quantum dynamics and the classical dynamics is made at a very small scale. For simplicity, a gas with collisions is modelled by an `Arnold gas'.Comment: 11 pages, LaTeX, no figures, title change

The Gisin-Percival stochastic Schrödinger equation from standard quantum filtering theory

We show that the quantum state diffusion equation of Gisin and Percival, driven by complex Wiener noise, is equivalent up to a global stochastic phase to quantum trajectory models. With an appropriate feedback scheme, we set up an analogue continuous measurement model with exactly simulates the Gisin-Percival quantum state diffusion.Comment: Originally submitted to a Theoretical Physics journal but rejected with the re-submission instructions to drop my discussion and references to the papers of Gisin and Percival, which I consider unethical. To be now submitted to an appropriate Mathematical Physics journal instea

PERCIVAL mission to Mars

With the downturn of the world economy, the priority of unmanned exploration of the solar system has been lowered. Instead of foregoing all missions to our neighbors in the solar system, a new philosophy of exploration mission design has evolved to insure the continued exploration of the solar system. The 'Discovery-class' design philosophy uses a low cost, limited mission, available technology spacecraft instead of the previous 'Voyager-class' design philosophy that uses a 'do-everything at any cost' spacecraft. The Percival Mission to Mars was proposed by Ares Industries as one of the new 'Discovery-class' of exploration missions. The spacecraft will be christened Percival in honor of American astronomer Percival Lowell who proposed the existence of life on Mars in the early twentieth century. The main purpose of the Percival mission to Mars is to collect and relay scientific data to Earth suitable for designing future manned and unmanned missions to Mars. The measurements and observations made by Percival will help future mission designers to choose among landing sites based on the feasibility and scientific interest of the sites. The primary measurements conducted by the Percival mission include gravity field determination, surface and atmospheric composition, sub-surface soil composition, sub-surface seismic activity, surface weather patterns, and surface imaging. These measurements will be taken from the orbiting Percival spacecraft and from surface penetrators deployed from Mars orbit. The design work for the Percival Mission to Mars was divided among four technical areas: Orbits and Propulsion System, Surface Penetrators, Gravity and Science Instruments, and Spacecraft Structure and Systems. The results for each of the technical areas is summarized and followed by a design cost analysis and recommendations for future analyses