A problem for Goldman on rationality
نویسندگان
چکیده
منابع مشابه
A Rationality Problem of Some Cremona Transformation
Let k be any field, k(x, y) be the rational function field of two variables over k. Let σ be a k-automorphism of k(x, y) defined by σ(x) = −x(3x− 9y − y) (27x+ 2x + 9xy + 2xy − y) , σ(y) = −(3x+ y)(3x− 9y − y) 27x+ 2x + 9xy + 2xy − y . Theorem. The fixed field k(x, y) is rational (= purely transcendental) over k. Embodied in the proof of the above theorem are several general guidelines for solv...
متن کاملGoldman Flows on a Nonorientable Surface
Given an embedded cylinder in an arbitrary surface, we give a gauge theoretic definition of the associated Goldman flow, which is a circle action on a dense open subset of the moduli space of equivalence classes of flat SU(2)-connections over the surface. A cylinder in a compact nonorientable surface lifts to two cylinders in the orientable double cover, and the composite flow is the compositio...
متن کاملA Quantum Goldman Bracket for Loops on Surfaces
In the context of (2+1)–dimensional gravity, we use holonomies of constant connections which generate a q–deformed representation of the fundamental group to derive signed area phases which relate the quantum matrices assigned to homotopic loops. We use these features to determine a quantum Goldman bracket (commutator) for intersecting loops on surfaces, and discuss the resulting quantum geometry.
متن کاملthe algorithm for solving the inverse numerical range problem
برد عددی ماتریس مربعی a را با w(a) نشان داده و به این صورت تعریف می کنیم w(a)={x8ax:x ?s1} ، که در آن s1 گوی واحد است. در سال 2009، راسل کاردن مساله برد عددی معکوس را به این صورت مطرح کرده است : برای نقطه z?w(a)، بردار x?s1 را به گونه ای می یابیم که z=x*ax، در این پایان نامه ، الگوریتمی برای حل مساله برد عددی معکوس ارانه می دهیم.
15 صفحه اولPatricia Goldman-Rakic A Remembrance
In the 1960s, scientists were conquering improbable frontiers: the moon was about to be walked upon; the brain cracked open. Neuroscientists were discovering that the secrets of the visual cortex could be broken with single-cell recordings and new anatomical tracing techniques, revealing an extraordinary organization: columns of cells responsive to only one eye; single cells tuned to a specific...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Social Epistemology
سال: 2000
ISSN: 0269-1728,1464-5297
DOI: 10.1080/02691720010008608