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Dr. Robert M. L. Baker
local time: 2020-04-04 10:38 (-07:00 DST)
Dr. Robert M. L. Baker (Abstracts)
Titles Abstracts Details
  • Generalized Generators of Very-High-Frequency Gravitational Waves Including Ring Devices (2009) [Updated 3 years ago]

    A number of researchers have previously proposed methods of generating very-high frequency gravitational waves (VHFGWs) using various interactions and mechanisms. These included mechanical devices, electromagnetic actuators, film bulk acoustic resonators (FBARs) using magnetron excitation, and nuclear explosions. In most cases the generated VHFGW power is a minute fraction of the input power needed to create the required excitation. Only on using a nuclear interaction is the output power significant; however, this appears not to be a practical generation method that can potentially achieve wide usage, at least in the near future. When a number of sources interfere constructively the amplitudes add in direct proportion to the number of radiation-element pairs or sources, N, and the radiation pattern narrows correspondingly in proportion to 1/N. Thus, the generated radiation flux (power per unit cross-sectional area) is proportional to the square of the number of sources or radiation element pairs, N2. Therefore, far greater GW power is obtained by using a larger number of smaller sources (consisting of mass pairs) excited (or ?jerked?) in phase rather than by using a smaller number of large excited (jerked) masses. The present paper examines the consequences of this scaling law to find how to optimize the generation of VHFGW power from a general set of jerked masses so that the result derives from the combination of all the individual excitations. Extreme cases that can be readily achieved using conventional known technology are firstly to jerk a set of atomic nuclei in phase, and secondly to jerk a set of electrons in phase. The former case uses most of the available mass and the second case sacrifices the excitations available from the masses of the corresponding nuclei. Specific devices, consisting of a ring or tube formed of rings of infra-red-excited molecules or electrons, are suggested. Algebraic and numerical estimates are given of the corresponding VHFGW flux produced by these devices under energizing power. For the multi-ring design, theoretical estimates of the GW flux under optimum conditions reach values on the order of 1 ?W. These novel designs may possibly be the most efficient and practical laboratory-based GW generators suggested so far, a significant advance because of the well-known difficulty of generating GW having significant amplitude.


  • The Peoples Republic of China High-Frequency Gravitational Wave Research Program (2009) [Updated 3 years ago]

    For the past decade the Peoples Republic of China has been increasingly active in the pursuit of High- Frequency Gravitational Wave (HFGW) research. Much of their progress has been during 2008. An epochal achievement was the publication of the theoretical analysis of the Li-Baker HFGW detector in the European Physical Journal C (Li, et al., 2008), ?Perturbative Photon Fluxes Generated by High-Frequency Gravitational Waves and Their Physical Effects?). Many Chinese scientists and graduate students have participated in these HFGW studies and their contributions are briefly discussed. Some of the key scientists and their institutions are as follows: first from Chongqing University: Zhenyun Fang, Director of the Institute of Theoretical Physics, Xing gang Wu, The Institute of Theoretical Physics, Nan Yang, The Institute of Gravitational Physics; Jun Luo, Huazhong University of Science and Technology (HUST), Wuhan, China, the Head of Gravitational Laboratory, Yang Zhang, University of Science and Technology of China, Associate Dean of the College of Sciences, Biao Li, Institute of Electronic Engineering of China Academy of Engineering Physics (CAEP), Chief of Microwave Antenna Division, Chuan-Ming Zhou, Technology Committee of Institute of Electronic Engineering of the CAEP, Jie Zhou, Institute of Electronic Engineering of the CAEP, Chief of the Signal Processing Division; Weijia Wen, Department of Physics, The Hong Kong University of Science and Technology. This Chinese HFGW team includes two parts: (1) Theoretical study and (2) Experimental investigation.

     

    These two parts have closed relations, and many cross projects, including cooperation between the American GravWave and Chinese HFGW teams. Referring to financial support, The Institute of Electronic Engineering (i.e., Microwave Laboratory) has already (June 2008) provided support more than three million Yuan for the HFGW detection project and this activity is discussed.


  • Radiation Pattern for a Multiple-Element HFGW Generator (2009) [Updated 3 years ago]

    We calculate the values for the High-Frequency Gravitational Wave (HFGW) radiation pattern for a multipleelement HFGW generator in the ?far field,? that is the field many wavelengths away from the generator. We extend Baker, Davis and Woods (2005) for a single GW-emission pair to include an in-phase, linear array of N such pairs as discussed in Baker, Stephenson and Li (2008). We calculate new values for the variable K in Baker, Davis and Woods (2005) by decreasing the integration interval of ? from 10? to 1?. This provides us with a K value of increased accuracy. The improved K has a value of 7.6x10-7 deg-2 and is used to find the power intensity, I(?), of a single GW source in terms of watts per square degree over the radiation-pattern cap The ? half-power-point angle for a single GW-emission pair at their mid-way-point focus is also recalculated and found to be 47.5?. We utilize the result of Romero and Dehnen (1981) and Dehnen and Romero (2003) for an increase in HFGW flux (in a linear array of N in-phase radiation elements) proportional to N2. This result is employed to compute the half-power-point angle, idealized radiation cap area and the HFGW flux/power-of-a-single-radiation-element at a distance of several wave lengths away, for example one meter from the end of a linear and a double-helical array in Wm-2 as a function of N. The notional picture shown of an idealized needle-like radiation beam is in the far field. It is described at a distance far enough from the generator that it is beyond the conventional diffraction limit of a beam's radiation-pattern cap area. It is found that the HFGW flux calculated is small, but that the Li-Baker detector may be capable of sensing the HFGWs generated in a laboratory setting.


  • Input Power Requirements for High-Frequency Gravitational Wave Generators (2009) [Updated 3 years ago]

    An analysis is accomplished of the input power requirement of High-Frequency Gravitational Wave (HFGW) generators. Several techniques are explored using both off-the-shelf and advanced-nanotechnology generator elements. It is concluded that proof-of-concept test, involving N off-the-shelf array elements could be of meter to kilometer length and require 25 MW or less power if array elements are in a staggered arrangement. The power and size of an operational nanotechnology HFGW generator or transmitter device can be greatly reduced by the focusing effect of N2 radiator pairs. Utilization of conventional piezoelectric Film Bulk Acoustic Resonators (FBARs), tailored and scaled for HFGW generation, could provide the initial commercial generation means. The use of the new infrared-energized ring concept of Woods and the use of a double helix array proposed by Baker may even further reduce the power and size requirements of the device to <<20 W and mm in length and width.