Do the laws of quantum physics still hold for macroscopic objects - this is at the heart of Schrödinger’s cat paradox - or do gravitation or yet unknown effects set a limit for massive particles? What is the fundamental relation between quantum physics and gravity? Ground-based experiments addressing these questions may soon face limitations due to limited free-fall times and the quality of vacuum and microgravity. The proposed mission Macroscopic Quantum Resonators (MAQRO) may overcome these limitations and allow addressing such fundamental questions. MAQRO harnesses recent developments in quantum optomechanics, high-mass matter-wave interferometry as well as state-of-the-art space technology to push macroscopic quantum experiments towards their ultimate performance limits and to open new horizons for applying quantum technology in space. The main scientific goal is to probe the vastly unexplored ‘quantum-classical’ transition for increasingly massive objects, testing the predictions of quantum theory for objects in a size and mass regime unachievable in ground-based experiments. The hardware will largely be based on available space technology. Here, we present the MAQRO proposal submitted in response to the 4th Cosmic Vision call for a medium-sized mission (M4) in 2014 of the European Space Agency (ESA) with a possible launch in 2025, and we review the progress with respect to the original MAQRO proposal for the 3rd Cosmic Vision call for a medium-sized mission (M3) in 2010. In particular, the updated proposal overcomes several critical issues of the original proposal by relying on established experimental techniques from high-mass matter-wave interferometry and by introducing novel ideas for particle loading and manipulation. Moreover, the mission design was improved to better fulfill the stringent environmental requirements for macroscopic quantum experiments.

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宏观量子谐振器（MAQRO）：2015年更新

量子物理学定律是否仍然适用于宏观物体-这是薛定ding猫悖论的核心-还是引力或未知效应为大粒子设置了限制？量子物理学与重力之间的基本关系是什么？由于自由落体时间有限以及真空和微重力的质量，地面实验解决了这些问题，可能很快就会面临局限性。拟议的任务宏观量子谐振器（MAQRO）可以克服这些限制并允许解决这些基本问题。MAQRO充分利用了量子光力学，高质物质波干涉测量技术以及最新的太空技术的最新发展，将宏观量子实验推向了极限性能极限，并为在太空中应用量子技术开辟了新的视野。主要的科学目标是探索越来越大的物体在很大程度上尚未探索的“量子经典”过渡，测试在地面实验中无法达到的尺寸和质量状态下物体的量子理论预测。硬件将主要基于可用的空间技术。在这里，我们介绍了MAQRO提案，该提案是应欧洲航天局（ESA）于2014年提出的第四次中型飞行任务（M4）的要求而提交的，并可能在2025年发射，并回顾了相关进展MAQRO最初提出的关于“第三次宇宙视觉”的建议要求在2010年进行中型任务（M3）。特别是，更新后的提案通过依靠高质量物质波干涉测量法建立的实验技术，并引入了粒子装载和操纵的新思路，克服了原提案的几个关键问题。此外，任务设计进行了改进，以更好地满足宏观量子实验的严格环境要求。