RUI: Energy Density Fluctuations, Negative Energy Detection and Gravity

该奖项支持研究，以了解“负能量”的属性。“一个重点是间接检测这种不寻常形式的能量的方法，部分使用量子光学领域开发的技术。PI和一名合作者将与一名实验人员合作，以确定此类检测是否可行。第二个主要重点将是研究真空中能量涨落的分布。与我们日常生活中的经验相反，量子物理学定律告诉我们，“空”的空间并不是真正的空，而是由永远存在的能量波动组成的。真空中能量的平均值为零，正如人们所期望的那样，但量子力学说，在这个平均值周围一定有波动。为了平均到零，必须有负的波动和正的波动。那么，在一次测量中得到负值的可能性有多大？以前的工作产生了一个令人惊讶的高概率的一个空间维度。目前的努力是试图确定这种"概率分布"在我们生活的三维空间世界中的形式，量子力学定律允许存在能量低于真空的状态。 如果对负能量没有限制，那么奇异的宏观效应可能成为可能。这些将包括虫洞和曲速驱动器的速度超过光速，违反热力学第二定律（例如，没有电源的冰箱），以及黑洞的毁灭。然而，允许这种形式的能量存在的量子力学定律严重限制了它的行为。通常，负能量持续的时间越长，其大小就越小。这项工作处于量子理论、爱因斯坦的广义相对论和热力学领域的交界处。负能量的唯一直接探测器是重力，但在实验室中可获得的负能量的数量是微小的。因此，人们不得不求助于间接检测，例如测量负能量对原子衰变率的影响。能量涨落概率分布的形式是理解真空结构的关键，也对宇宙学等其他领域有影响。本科生正在准备通过PI开发的数学课程从事这项研究。

This award supports research to understand the properties of "negative energy." One focus is on methods of indirectly detecting this unusual form of energy using, in part, techniques developed in the field of quantum optics. The PI and a collaborator will work with an experimentalist to determine if such detection is feasible. A second major focus will be to study the distribution of energy fluctuations in the vacuum. Contrary to our experience in everyday life, the laws of quantum physics tell us that "empty" space is not really empty but consists of ever-present fluctuations of energy. The average value of the energy in empty space is zero, as one would expect, but quantum mechanics says that there must be fluctuations around this mean value. In order to average out to zero, there must be both negative as well as positive fluctuations. What is the likelihood then of getting a negative value in a single measurement? Previous work yields a surprisingly high probability for one spatial dimension. Current efforts are geared toward trying to determine the form of this "probability distribution" in the three-spatial-dimensional world in which we live.The laws of quantum mechanics allow the existence of states of energy that are lower than that of the vacuum. If there are no restrictions on negative energy, then bizarre macroscopic effects might become possible. These would include wormholes and warp drives for faster-than light travel, violations of the second law of thermodynamics (e.g., refrigerators with no power sources), and the destruction of black holes. However, the same laws of quantum mechanics which allow this form of energy to exist severely limit its behavior. Typically, the longer the negative energy lasts, the smaller its magnitude. This work lies at the juncture of the fields of quantum theory, Einstein's general relativity, and thermodynamics. The only direct probe of negative energy is gravity, but the amounts of negative energy obtainable in the laboratory are minute. Therefore, one has to resort to indirect detection, such as measuring the effect of negative energy on atomic decay rates. The issue of the form of the probability distribution for energy fluctuations is key to understanding the structure of the vacuum, and has implications for other fields such as cosmology. Undergraduates are being prepared to engage in this research through Mathematica-based courses developed by the PI.