Qubit state transfer via discrete-time quantum walks

We propose a scheme for perfect transfer of an unknown qubit state via the discrete-time quantum walk on a line or a circle. For this purpose, we introduce an additional coin operator which is applied at the end of the walk. This operator does not depend on the state to be transferred. We show that perfect state transfer over an arbitrary distance can be achieved only if the walk is driven by an identity or a flip coin operator. Other biased coin operators and Hadamard coin allow perfect state transfer over finite distances only. Furthermore, we show that quantum walks ending with a perfect state transfer are periodic.Comment: 13 pages, 5 figure

Two-dimensional quantum walk under artificial magnetic field

We introduce the Peierls substitution to a two-dimensional discrete-time quantum walk on a square lattice to examine the spreading dynamics and the coin-position entanglement in the presence of an artificial gauge field. We use the ratio of the magnetic flux through the unit cell to the flux quantum as a control parameter. For a given flux ratio, we obtain faster spreading for a small number of steps and the walker tends to be highly localized around the origin. Moreover, the spreading of the walk can be suppressed and decreased within a limited time interval for specific rational values of flux ratio. When the flux ratio is an irrational number, even for a large number of steps, the spreading exhibit diffusive behavior rather than the well-known ballistic one as in the classical random walk and there is a significant probability of finding the walker at the origin. We also analyze the coin-position entanglement and show that the asymptotic behavior vanishes when the flux ratio is different from zero and the coin-position entanglement become nearly maximal in a periodic manner in a long time range.Comment: 7 pages, 5 figures, sections 3 and 4 revise

An overview of European activities on microgravity combustion

The global objective of the European efforts in microgravity combustion is to combine theoretical and experimental work, both under normal and reduced gravity, to progress in the basic understanding of gravity dependent phenomena in various combustion situations. The first phase of the European activities on microgravity combustion has been summarized in refs. 1, 2, and 3. This overview will summarize the more recent developments. The focus will be on new experimental facilities, new research topics, and new collaborative efforts

A Mongolian horsepacking adventure through my paranoid poetics of digital ontology

This is not quite an essay. It is more of a scientific experiment conducted with words. It titrates the paranoid poetics of critique with the narrative practices of social media to precipitate a postcritical theory of digital ontology. The organic compounds used in this titration were extracted from a 16-month mine of ethnography among digitalreal tourists known as Dimecams. This ethnographic mine was full of participant-observations among the “digital” and “real” aggregates of horsepacking adventures in Mongolia. Starting with myths of Mongolian adventures that circulate in the backpacker communities of Asia, this experiment rewires the narrative circuits of exploration to illuminate two distinct iterations of adventure—the “real” and the “digital.” Common sense would have it that digital adventures appearing on social media are “representations” of real adventures from the flesh. The experiments I conducted, however, demonstrated that the digital and the real are actually two separate ontologies in which different types of adventures occur. Real adventures are full of misery and hunger while digital adventures are nothing but epic selfies and unhinged freedom. The radical alterity between these two kinds of adventures necessitated a turn towards ontology. However, in this ontological turn, my experiment spun out of control and crystallized as a fractal. That fractal was later revealed to be a continuously self-referential postcritique of the paranoid poetics of critique. The same fractal was also shown to be the operational procedure which kept the narrative ontology of digital adventures afloat in a self-sustaining world that endlessly retold itself into existence. What emerged at the end of this experiment was a not-quite-ontology composed of not-quite-beings—which, in the not-too-distant future, will detach itself from reality entirely, drifting off into space and forming a new planetAnthropolog

Status of the CNRS-LCSR program on high pressure droplet vaporization and burning

Depending on the surrounding flow and thermodynamic conditions, a single droplet may experience several gasification regimes, ranging from the envelope flame regime to pure vaporization. In practical situations, such as rocket propulsion or diesel combustion, the size distribution of droplets is, at best, bimodal, so that the possibility exists for the simultaneous presence of various regimes. For example, very small droplets are transported by the gas phase with zero relative velocity. This picture validates then the spherical symmetry hypothesis applied to the droplet and to the diffusion flame enveloping it. On the other hand, for larger droplets, a relative velocity exists due to drag forces. The most important influence of forced convection on droplet burning is the possibility to extinguish globally the envelope flame, or to establish a flame stabilized in the wake region. The burning rates of these regimes differ strongly. The characteristic time of droplet gasification is also influenced by the surrounding pressure and temperature. A parametric investigation of single droplet burning regimes is then helpful in providing the necessary physical ideas for sub-grid models used in spray combustion numerical prediction codes. The CNRS-LCSR experimental program on droplet vaporization and burning deals with these various regimes: stagnant and convective monocomponent droplet burning convective mono and bicomponent droplet vaporization; high temperature convective mono and biocomponent droplet vaporization; burning regimes of hydrazine and hydroxyl-ammonium-nitrate based monopropellant droplets and the vaporization regimes of liquid oxygen droplets. Studies on interacting droplets and on liquid aluminum droplets will start in the near future. The influence of high pressure is a common feature of all these studies. This paper summarizes the status of the CNRS-LCSR program on the effects of high pressure on monocomponent single droplet burning and vaporization, and some recent results obtained under normal and reduced gravity conditions with suspended droplets are presented. In the work described here, parabolic flights of an aircraft is used to create a reduced gravity environment of the order of 10(exp -2) g

EFFECTS OF POST-FIRE SALVAGE LOGGING ON COMPACTION, INFILTRATION, WATER REPELLENCY, AND SEDIMENT YIELD AND THE EFFECTIVENESS OF SUBSOILING ON SKID TRAILS

Post-fire salvage logging operations can induce environmental problems. This study assessed the effects of different disturbances from post-fire salvage logging on soil bulk density, water repellency, field saturated hydraulic conductivity (Kfs), ground cover, and sediment yields after the 2013 Rim Fire in California. Hillslope plots were installed in three locations (Sawmill, lower Femmons, and upper Femmons). The plot-scale disturbances were burned and untrafficked (low and high slope controls and logged only with no traffic), or burned and trafficked (few and many pass skid trails). Additional measurements were made in nearby areas that included the plot-scale disturbances as well as feller buncher tracks and mixed disturbed areas. We measured soil bulk density at two depths. Kfs was measured using a dual head ring infiltrometer. Water repellency was measured at the mineral soil surface and at 1 cm and 3 cm soil depths. Ground cover was measured in each hillslope plot. Sediment yields from the hillslope plots were measured using sediment fences. Measurements in burned areas were made in water years 2015 and 2016. Bulk density, water repellency, and Kfs measurements were also made in one unburned logged site. We assessed the effectiveness of subsoiling of skid trails in nearby burned areas, sometimes across the contour, as a mitigation practice by recording the presence or absence of rills or gullies. The mean bulk densities in the trafficked plots were significantly higher than in untrafficked plots. Kfs was 10 times higher in untrafficked areas than in the many pass skid trails in the burned sites and significantly higher in the unburned site. There was no significant difference in KFS for any of the disturbance classes between the burned and unburned sites. In the burned areas, WDPT was highest at the 3 cm depth and was lower in trafficked areas than untrafficked areas. WDPT was also significantly lower in burned areas than in unburned areas, where strong water repellency occurred across all depths and disturbance conditions. Untrafficked areas had relatively low bare soil in 2015 and the amount of bare soil decreased significantly in 2016. The trafficked plots had more bare soil than the untrafficked plots, and sometimes the differences were significant. The annual sediment yield in the untrafficked plots in the Sawmill site was 1.9 Mg ha-1 in the 2015 water year and this value significantly decreased to 0.14 Mg ha-1 in the 2016. The sediment yields in the trafficked skid trail plots were 6.2 and 1.2 Mg ha-1 in 2015 and 2016, respectively, and the 2016 yield was significantly greater than the untrafficked value. The annual sediment yields were also very low in untrafficked plots in the Femmons sites in 2016, and the trafficked plots produced significantly higher sediment yields. Some of the many pass skid trails were subsoiled (ripped) by logging contractors as part of the logging operation using a winged subsoiler with the wings set 45-60 cm below the soil surface. 53% of the 53 subsoiled skid trails had no rills or gullies present, and the rate of rilling or gullying increased with increasing skid trail slope. Subsoiling of skid trails with slopes more than 6% was not effective at reducing erosion because of the high incidence of rills or gullies. These results indicate that salvage logging equipment compacted the soil in the burned forest. Soil compaction reduced water repellency and Kfs and increased bulk density, bare soil, and sediment yields. The sediment yields were most closely related to the change in bare soil. To reduce sediment yields from salvage logging, forest managers should consider increasing the ground cover on skid trails and other trafficked areas

Cultural transformation and translation: Kültürel dönüşüm ve çeviri olgusu

Along with the cultural transformation and renewal process of the world, the need for reinterpretation in the field of translation has come to the fore. The increase in cultural activities and transformations has led to the emergence of new dimensions in the communication and interaction of societies. Especially after the second half of the 20th century, the rapid social, economic and cultural mobility, which started to gain a new dimension, intensified the cultural interaction, and also led to the production of many written and oral works in this field. The dimensions of cultural data transfer, including these produced works, have begun to increase. The most important role in the transfer of these data between cultures and languages ​​is the translation institution, which has the importance of a cultural carrier beyond being a purely linguistic transmission tool. In this study, firstly, the concept of culture is examined within the general framework. Following this, the concept of translation and its relationship with the phenomenon of culture are discussed. In the study, an answer is sought to the question of what exactly is understood from the concept of culture. Finally, the complementarity effect of the concepts of translation and culture is emphasized. ​Extended English summary is in the end of Full Text PDF (TURKISH) file. Özet Dünyanın geçirdiği kültürel dönüşüm ve yenilenme süreci ile çeviri sürecini yeniden yorumlanma ihtiyacı ön plana çıkmaya başlamıştır. Kültürel faaliyetlerin ve dönüşümlerin yaşanmasındaki artış toplumların iletişim ve etkilişimde de yeni boyutların ortaya çıkmasına neden olmuştur.  Özellikle 20. yüzyılın ikinci yarısından sonra yaşanmaya başlayan hızlı sosyal, ekonomik ve kültürel hareketlilik yeni bir boyut kazanmaya başlayan kültürel etkileşimin yoğunlaşmasını sağlarken bu alanda birçok yazılı ve sözlü eserin üretilmesine de yol açmıştır. Üretilen bu eserler de dahil olmak üzere kültürel veri transferinin boyutları da artmaya başlamıştır. Bu verilerin kültürler ve diller arasında transferindeki en önemli rol ise salt dilsel aktarım aracı olmasından öte kültürel bir taşıyıcılık önemi de haiz olan çeviri müssesesindedir. Bu çalışmada ilk olarak kültür kavramı genel çerçeve içerisinde ele alınarak irdelenmektedir. Bunu müteakiben ise çeviri kavramı ve kültür olgusu ile olan ilişkisi ele alınmaktadır. Çalışmada kültür kavramından tam olarak neyin anlaşılmakta olduğu sorusuna cevap aranmaktadır. Nihai olarak ise çeviri ve kültür kavramlarının birbirine yaptığı tamamlayıcılık etkisi üzerinde durulmaktadır

[Kemal Tahir]

Taha Toros Arşivi, Dosya No: 133-Kemal Tahir ve Yorgun SavaşçıUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010