Studies Relating to Black Hole Evaporation and to the Validity of the Semiclassical Approximation in Cosmology

有关黑洞蒸发和宇宙学半经典近似有效性的研究

• 批准号: 1912584
• 负责人: Paul Anderson
• 金额: $ 15.18万
• 依托单位: Wake Forest University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-05-15 至 2023-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1912584&HistoricalAwards=false
• 关键词: Studies; Relating; Black; Hole; Evaporation

This award supports studies on black hole evaporation processes, with a focus on investigating quantum effects during and after the formation of a black hole. The results may provide insight into the important question of what happens to the information about how a black hole forms. Bose-Einstein condensates are systems that typically contain very cold atoms. For certain configurations, quantum effects will occur which are in some important ways similar to those that occur for black holes. Experimental studies of Bose-Einstein condensate analog black holes have been carried out. Theoretical calculations will be made using the same techniques as are used to study quantum effects related to real black holes. The results will be compared with the experimental data. The semiclassical approximation has been used to investigate quantum effects such as particle production in a variety of situations including the early universe. It provides a bridge between macroscopic (classical) and microscopic (quantum) phenomena. It's validity will be studied for an important model in which the universe is initially contracting, reaches a minimum size, and then begins to expand. Particle production is expected to be particularly important during the contracting phase where it could significantly alter the dynamical evolution of the universe. The results will help to determine whether the semiclassical approximation is valid in cases where quantum effects are significant. Four graduate students, and probably some undergraduates, will participate in some aspects of the research, continuing a long history of their training in numerical and analytical research techniques and co-authorship on publications. Results will be disseminated to the research community through publications and presentations at national and international meetings. Some results obtained will be relevant for condensed matter physics.The research supported by this grant addresses black hole evaporation, observable effects in Bose-Einstein condensates which can serve as black hole analogs, and early universe cosmology. Specifically, it will investigate questions related to the information about how a black hole forms, the correspondence between theoretical and experimental results related to quantum effects in analog black hole systems, and the validity of the semi-classical approximation in models of the universe. In the case of black hole evaporation, the objectives include studying in detail quantum effects that occur if a spherically symmetric null shell collapses to form a black hole. One goal is to check the accuracy of similar calculations in two dimensional dilaton theories of gravity. It is also possible that insight will be gained into the question of what happens to the information about how the black hole formed. Bose-Einstein condensates that can serve as analog black holes have been created in the laboratory. The goal is to determine whether certain experimental results are in quantitative agreement with predictions resulting from quantum field theory in curved space calculations in the analog spacetime. The primary goal for cosmology is to determine whether the semiclassical approximation is valid for models in which the universe contracts to a minimum size and then expands. The models used will consist of a closed universe with a positive cosmological constant. For the black hole evaporation project the stress-energy tensor for a quantized massless minimally coupled scalar field will be numerically computed in four-dimensions in the case of a null shell that collapses to form the black hole. For the cosmology project the semiclassical backreaction equations will be solved numerically in the case that a massive conformally coupled scalar field is present. The results will be used to investigate the validity of the semiclassical approximation in a collapsing universe. The density density correlation function for a Bose-Einstein condensate analog black hole will be computed using quantum field theory in curved space techniques for a model that closely matches the velocity and sound speed profiles used in the experiments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项支持对黑洞蒸发过程的研究，重点是研究黑洞形成期间和之后的量子效应。 这些结果可能会让我们深入了解黑洞如何形成的信息会发生什么。 玻色-爱因斯坦凝聚体是一种典型的包含非常冷的原子的系统。 对于某些配置，量子效应将发生，在某些重要方面类似于黑洞发生的那些。 对玻色-爱因斯坦凝聚态类黑洞进行了实验研究。 理论计算将使用与研究与真实的黑洞有关的量子效应相同的技术。 将计算结果与实验数据进行比较。半经典近似已经被用来研究量子效应，例如在包括早期宇宙在内的各种情况下的粒子产生。 它提供了宏观（经典）和微观（量子）现象之间的桥梁。 它的有效性将研究一个重要的模型，其中宇宙最初收缩，达到最小尺寸，然后开始膨胀。 预计粒子的产生在收缩阶段特别重要，它可以显着改变宇宙的动力学演化。 结果将有助于确定在量子效应显著的情况下半经典近似是否有效。 四名研究生，可能还有一些本科生，将参与研究的某些方面，继续他们在数值和分析研究技术方面的长期培训，并共同撰写出版物。 研究结果将通过出版物和在国家和国际会议上的介绍传播给研究界。 部分研究成果将与凝聚态物理学有关。该基金支持的研究涉及黑洞蒸发、玻色-爱因斯坦凝聚态中可观测到的效应（可作为黑洞类似物）以及早期宇宙宇宙学。具体来说，它将调查有关黑洞如何形成的信息，与模拟黑洞系统中量子效应相关的理论和实验结果之间的对应关系，以及宇宙模型中半经典近似的有效性。 在黑洞蒸发的情况下，目标包括详细研究如果球对称零壳层坍缩形成黑洞时发生的量子效应。 其中一个目标是检查在两维引力场理论中类似计算的准确性。 也有可能深入了解黑洞如何形成的信息会发生什么变化。 玻色-爱因斯坦凝聚体可以作为模拟黑洞已经在实验室中创建。 目标是确定某些实验结果是否与量子场论在模拟时空中弯曲空间计算中的预测定量一致。 宇宙学的主要目标是确定半经典近似是否适用于宇宙收缩到最小尺寸然后膨胀的模型。 所使用的模型将由具有正宇宙学常数的封闭宇宙组成。 对于黑洞蒸发计划，在零壳层坍缩形成黑洞的情况下，将在四维中数值计算量子化无质量最小耦合标量场的应力-能量张量。 在宇宙学计划中，我们将数值求解大质量共形耦合标量场情况下的半经典反反应方程。 这些结果将用于研究坍缩宇宙中半经典近似的有效性。 玻色-爱因斯坦凝聚态类似黑洞的密度相关函数将使用弯曲空间技术中的量子场论计算，模型与实验中使用的速度和声速剖面非常匹配。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Pair production due to an electric field in 1+1 dimensions and the validity of the semiclassical approximation

1 1 维电场导致的电子对产生以及半经典近似的有效性

• DOI: 10.1103/physrevd.103.105003
• 发表时间: 2021
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Pla, Silvia;Newsome, Ian M.;Link, Robert S.;Anderson, Paul R.;Navarro-Salas, Jose
• 通讯作者: Navarro-Salas, Jose

Linear growth of the two-point function for the Unruh state in 1 + 1 dimensional black holes

1 1 维黑洞中 Unruh 态两点函数的线性增长

• DOI: 10.1142/9789811269776_0100
• 发表时间: 2023
• 期刊: Proceedings of the Sixteenth Marcel Grossmann Meeting on General Relativity
• 作者: Anderson, Paul R.;Scofield, Zachary P.;Traschen, Jennie
• 通讯作者: Traschen, Jennie

Semiclassical predictions regarding a preinflationary era and its effects on the power spectrum

关于暴胀前时代的半经典预测及其对功率谱的影响

• DOI: 10.1103/physrevd.102.063528
• 发表时间: 2020
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Anderson, Paul R.;Carlson, Eric D.;Ordines, Taylor M.;Hicks, Bradley
• 通讯作者: Hicks, Bradley

Horizons and correlation functions in 2D Schwarzschild-de Sitter spacetime

二维史瓦西-德西特时空中的视界和相关函数

• DOI: 10.1007/jhep01(2022)192
• 发表时间: 2022
• 期刊: Journal of High Energy Physics
• 影响因子: 5.4
• 作者: Anderson, Paul R.;Traschen, Jennie
• 通讯作者: Traschen, Jennie

Correlations between a Hawking particle and its partner in a 1+1D Bose-Einstein condensate analog black hole

1 1D 玻色-爱因斯坦凝聚模拟黑洞中霍金粒子与其伙伴之间的相关性

• DOI: 10.1103/physrevd.102.105005
• 发表时间: 2020
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Dudley, Richard A.;Fabbri, Alessandro;Anderson, Paul R.;Balbinot, Roberto
• 通讯作者: Balbinot, Roberto