Backreaction Effects in Classical and Semiclassical Gravity

*** 9800971anderson Paul Anderson教授将开展几个与半经典重力反作用有关的项目。有三个项目与黑洞时空中的量子效应研究有关。它们包括寻找可能对应于黑洞残余物的半经典反反应方程的解，研究量子化场对黑洞内部的影响，以及研究量子效应如何影响在引力坍缩中发现的关键现象。另一个项目涉及研究粒子产生对宇宙膨胀的影响。对黑洞的研究将解决与黑洞研究有关的几个重要问题。寻找与黑洞残余物相对应的半经典反反应方程的解，将解决有关黑洞蒸发过程终点的问题，以及关于黑洞如何形成的信息发生了什么。对黑洞内部量子效应的研究将解决量子效应是否可以消除黑洞中心的奇点，消散黑洞内部的各向异性，或者改变带电黑洞内部的因果结构等问题。在经典引力坍缩中发现了一些临界现象。预计对引力坍缩过程中临界现象的研究将表明量子效应对这一过程有重要影响。平坦性问题与宇宙为何以今天的方式膨胀有关。除非它在空间上是平坦的，否则爱因斯坦方程的一般解会预测，今天的宇宙将以一种与现在截然不同的方式收缩或膨胀。先前的研究表明，如果早期宇宙中产生了足够多的粒子，那么这个问题就可以用自然的方式解决。将对早期宇宙中产生粒子的各种来源进行检查，看看是否有足够的粒子产生来解决平坦性问题。还将研究宇宙振荡模型中的粒子产生。预计在这些模型中，颗粒生产肯定可以用来解决平面问题

***9800971AndersonProfessor Paul Anderson will carry out several projects relating to backreaction effects in semiclassical gravity. Three projects relate to the study of quantum effects in black hole spacetimes. They include a search for solutions to the semiclassical backreaction equations that could correspond to black hole remnants, an investigation of the effects which quantized fields have on the interior of a black hole, and a study of how quantum effects influence critical phenomena that have been found in gravitational collapse. Another project involves the study of the effects of particle production on the expansion of the universe.The research on black holes will address several important issues relating to the study of black holes. The search for solutions to the semiclassical backreaction equations that could correspond to black hole remnants will address questions regarding the end point of the black hole evaporation process and what happens to the information about how a black hole formed. The study of quantum effects inside of black holes will address the questions of whether quantum effects can remove the singularity at the center of a black hole, dissipate anisotropy in the interior of a black hole, or alter the causal structure inside of a charged black hole. Critical phenomena have been found in classical gravitational collapse. It is expected that the investigation of critical phenomena during gravitational collapse will show that quantum effects have a significant influence on this process. The flatness problem is related to the question of why the universe is expanding the way it is today. Unless it is spatially flat, a generic solution of Einstein's equations would predict that today the universe would be either contracting or expanding in a very different manner than it is. Previous work has shown that if engough particle production occurs in the early universe then this problem can be solved in a natural way. Various sources of particle production in the early universe will be examined to see if enough particle production could have taken place to solve the flatness problem. Particle production in oscillating models of the universe will also be studied. It is expected that in these models particle production can definitely be used to solve the flatness problem.***