Electromagnetic Fields Derived from Non-Commuting Potentials
نویسندگان
چکیده
منابع مشابه
Coupling of nonlocal potentials to electromagnetic fields.
Nonlocal Hamiltonians are used widely in first-principles quantum calculations; the nonlocality stems from eliminating undesired degrees of freedom, e.g., core electrons. To date, attempts to couple nonlocal systems to external electromagnetic (EM) fields have been heuristic or limited to weak or long wavelength fields. Using Feynman path integrals, we derive an exact, closed-form coupling of a...
متن کاملcommuting and non -commuting graphs of finit groups
فرض کنیمg یک گروه غیر آبلی متناهی باشد . گراف جابجایی g که با نماد نمایش داده می شود ،گرافی است ساده با مجموعه رئوس که در آن دو راس با یک یال به هم وصل می شوند اگر و تنها اگر . مکمل گراف جابجایی g راگراف نا جابجایی g می نامیم.و با نماد نشان می دهیم. گرافهای جابجایی و ناجابجایی یک گروه متناهی ،اولین بار توسطاردوش1 مطرح گردید ،ولی در سالهای اخیر به طور مفصل در مورد بحث و بررسی قرار گرفتند . در ،م...
15 صفحه اولElectron tomography of electromagnetic fields, potentials and sources
The exit phase of an electron moving through electromagnetic potentials can, as is well known, be written as line integrals of the potentials. The use of vector tomography to reconstruct electromagnetic potentials from such phase measurements in a transmission electron microscope is proposed. Electromagnetic fields and source distributions can similarly be reconstructed from phase gradients and...
متن کاملFields with several Commuting Derivations
The existentially closed models of the theory of fields (of arbitrary characteristic) with a given finite number of commuting derivations can be characterized geometrically, in several ways. In each case, the existentially closed models are those models that contain points of certain differential varieties, which are determined by certain ordinary varieties. How can we tell whether a given syst...
متن کاملThe effects of electromagnetic fields on fish
The objective of this paper is to survey the results of studies on the biological effects of electromagnetic fields on fish. First, the basic concepts of electromagnetism and electromagnetic spectrum and the importance of studying it in the case of fish are discussed. Then a summary of the results obtained on the effects of extremely low frequency electromagnetic fields (ELF-EMFs) and radiofreq...
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: Proceedings of the National Academy of Sciences
سال: 1931
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.17.7.430