Theory and Applications of Observability of Classical And Quantized Radiation Fields

在经典的电磁辐射理论中，存在某些不辐射的局域电荷-电流分布。这样的源，通常被称为非辐射源，产生的场本身被限制在源的局部化区域内[1]。关于非辐射源的研究既涉及标量源[2，3，4，5]和电磁源[1，6，7，8]，也涉及确定性和随机源[9，10，11]。问题是，在量子理论中，非辐射源是否有(或没有)对应的源。令人惊讶的是，这个根本问题似乎以前没有得到解决。拟议的研究计划的主要目标是发展一种新的经典场和量子化场的非辐射源理论，并解决发展的理论的潜在和具体应用。具体的理论和应用目标描述如下。我们建议处理(经典的和量子电动力学的)单色和瞬变(例如脉冲)源和场。拟议研究的经典组成部分将侧重于开发新的工具，用于在时间和频率域中分析和综合非辐射源。该项目这一部分的目标包括：1)在时间域中发展新的逆源和非辐射源理论，2.开发完整的矢量函数集以表示紧凑支承的单色和瞬时非辐射源，以及3.)探索非辐射源和其他波对象之间的基本(和潜在的实用)联系，例如电磁学逆源问题的标量势和矢量势以及最小能量解。这些方面的拟议工作预计将与标量源和场的提出者先前的工作并行(并推广)。这项工作包括逆源问题的新公式[12]，以及非辐射源的新描述[13]，以及它们与最小能量源和理想散热器的联系[14]。概述的工作的理论部分预计也将给量子理论中非辐射源的性质带来光，从而有助于更基本地理解源和散射体及其场的可观性。其目的是最终回答量子理论中非辐射源的存在问题。此外，发展的理论可能会对量子理论的基本方面产生影响，特别是在一种有争议的、尚未完全理解的量子力学现象中，即Aharonov-Bohm效应，其中带电粒子可以受到经典的定域源及其场的影响，在这些场(因此粒子上的力)消失的区域[15，16]。因此，我们还建议研究Aharonov-Bohm效应和量子辐射场的可观性之间的联系。这一发展的理论可能为新的通信方案(基于非辐射源)以及新的源和散射体询问技术(硬件和算法)奠定基础。后几个方面构成了拟议研究的第二部分的重点，旨在应用。令人感兴趣的应用依赖于通过量子力学实验(即，新的场传感设备)来感知源的某些特征(例如，信息)的可能性，否则(即，通过经典传感器(天线))本来是无法观察到的。因此，基于Aharonov-Bohm效应和/或其他非常规、量子力学的场-粒子相互作用效应的新场传感器件的系统级设计也是拟议工作的潜在结果。与通信技术特别相关的是产生场的可能性，这些场经典地被限制(局部化)在信号源的支撑区(天线的结构)内，但在量子力学上不是这样的。后一种可能性潜在地打开了一扇有效、安全地传输场可观测物(sig-hals)的窗口，这些场可观测物由传统的源(天线)产生，但通过非传统的量子电动场传感器来感知。这样，例如，人们将获得额外的灵活性(在天线到天线通信中不可用)，以便通过仅对量子电动场传感器开放而对传统场传感器(接收天线)不可用的“通道”来传输全部或部分要传输的信息。总而言之，技术影响的主要领域--将作为拟议努力的一部分加以探讨--是1。新型场敏器件，2.)新的通信技术和3.)用于询问源和散射体的新算法和硬件。*

9900246ZiolkowskiIn the classical theory of electromagnetic radiation, there are certain localized charge-current distributions which do not radiate. Such sources, commonly referred to as nonradiating sources, generate fields which are themselves confined within the region of localization of the source [1]. Investigations on nonradiating sources have addressed both scalar [2, 3, 4, 5] and electromagnetic sources [1, 6, 7, 8] as well as both deterministic and random sources [9, 10, 11]. The question arises whether nonradiating sources have (or not) a counterpart in the quantum theory. Surprisingly, this fundamental question does not appear to have been addressed before. The main goal of the proposed program of research is to develop a new theory of nonradiating sources for both classical and quantized fields and to address potential and concrete applications of the developed theory. Specific theoretical and applicational aims of the projected research are described below.We propose to deal (classically and quantum-electrodynamically) with both monochromatic and transient (e.g., pulsed) sources and fields. The classical component of the proposed research will focus on developing new tools for analysis and synthesis of nonradiating sources in the time and frequency domains. The objectives of this portion of the project include: 1.) developing a new inverse source and nonradiating source theory in the time domain, 2.) developing complete sets of vector functions to represent monochromatic as well as transient nonradiating sources of compact support, and 3.) exploring fundamental (and potentially practical) connections between nonradiating sources and other wave objects, such as the scalar and vector potentials and minimum energy solutions to the inverse source problem of electromagnetics. The proposed work along those lines is expected to parallel (and generalize) previous work by the proposers for scalar sources and fields. That work includes new formulations of the inverse source problem [12] as well as new descriptions of nonradiating sources [13] and of their connection with minimum energy sources and perfect radiators [14]. The theoretical component of the outlined effort is expected to give light, also, into the nature of nonradiating sources in the quantum theory, thereby contributing to a more fundamental understanding of the observability of sources and scatterers and their fields. The purpose is to answer conclusively the question of existence of nonradiating sources in the quantum theory. Furthermore, the developed theory could have impact in fundamental aspects of quantum theory and, in particular, in a controversial, not fully-understood, quantum-mechanical phenomenon, namely, the Aharonov-Bohm effect, wherein charged particles can be influenced by classical, localized sources and their fields in regions where the fields (and therefore the forces on the particles) vanish [15, 16]. Thus, we propose also to examine the connection between the Aharonov-Bohm effect and the observability of quantised radiation fields.The developed theory could, potentially, set the stage for novel communication schemes (based on nonra-diating sources), as well as new techniques for interrogation of sources and scatterers (in both hardware and algorithms). The latter aspects constitute the focus of the second part of the proposed research, aimed at ap-plications. The applications of interest rely on the possibility of sensing via quantum-mechanical experiments (i.e., new field-sensing devices) certain features of a source (e.g., information) which would be otherwise (i.e., via classical sensors (antennas)) inherently unobservable. Thus, system-level designs for new field-sensing devices based, e.g., on the Aharonov-Bohm effect and/or other unconventional, quantum-mechanical field-particle interaction effects, are also potential outcomes of the proposed effort. Of particular relevance to communication technologies is the possibility of generating fields that are confined (localized), classically, within the source's region of support (antenna's structure), but that are not such quantum-mechanically. The latter possibility opens, potentially, a window for efficient, secured transmission of field-observables (sig-halS), generated by conventional sources (antennas) but sensed via unconventional, quantum-electrodynamic field-sensors. In this way, one would obtain, e.g., added flexibility (not available in antenna-to-antenna communication) for transmitting either all or part of the to-be-transmitted information via a "channel" that opens only to quantum-electrodynamic field-sensors while being unavailable to traditional field-sensors (receiving antennas). In summary, the main areas of technological impact - to be explored as part of the proposed effort - are 1.) novel field-sensing devices, 2.) new communications technology and 3.) new algorithms and hardware for interrogation of sources and scatterers.***