**Abstract:** A groundbreaking achievement in the field of quantum many-body physics has been reported by the research group led by Professor Li You from the Department of Physics at Tsinghua University. The team has successfully observed a "time crystal" in a strongly interacting room-temperature Rydberg gas, marking a significant step forward in the study of time crystals. This discovery was published in the prestigious journal *Nature Physics* on July 2, 2024, under the title "Dissipative Time Crystal in a Strongly Interacting Rydberg Gas." The concept of spontaneous symmetry breaking is fundamental in modern physics, explaining the formation of various quantum states of matter. For instance, the spontaneous breaking of spatial translation symmetry results in the ordered, periodic arrangement of atoms in space, leading to the creation of conventional crystals. Given the equivalence of space and time, a logical question arises: Can interactions cause the spontaneous breaking of time translation symmetry, leading to a crystalline structure in the time dimension? In 2012, Nobel laureate Frank Wilczek first proposed the theoretical existence of "time crystals." These systems would exhibit a continuous, self-repeating pattern over time, characterized by persistent periodic oscillations. Since then, the exploration of time crystals has been a focal point in quantum many-body physics. However, theoretical analyses have indicated that due to quantum fluctuations, continuous time crystals are unlikely to remain stable in equilibrium systems. The Tsinghua University research group, led by Professor Li You, has now made a significant breakthrough by observing stable and continuous time crystal signals in a strongly interacting Rydberg gas at room temperature. Unlike traditional finite-temperature systems, the experimental setup involves a non-equilibrium system where the long-range interactions between Rydberg atoms, coherent external field driving, and dissipative processes such as spontaneous emission work together to maintain the time crystal phase. This type of time crystal is specifically referred to as a "dissipative time crystal." The experimental setup (Figure 1) consists of a room-temperature atomic gas where atoms are excited to Rydberg states using coupling and probe light, creating an electromagnetically induced transparency (EIT) effect. A reference beam is used for differential measurement. The team observed that the oscillation amplitude of the time crystal signal remained stable over the experimental observation period, showing no signs of decay. Additionally, they measured the quench dynamics of the system and found that after a brief relaxation process, the system established a true long-range order in the time dimension, forming a stable (time) lattice structure (Figure 2). The observed oscillation signals were also found to be robust against external noise, maintaining their integrity even when subjected to strong artificial disturbances. This resilience is a crucial characteristic for the practical application and study of time crystals. To further understand the mechanisms behind the formation of the time crystal, the research team collaborated with Dr. Fan Yang from Aarhus University (now a postdoctoral researcher at the University of Innsbruck) and Professor Thomas Pohl from the Vienna University of Technology. They identified and experimentally verified another key mechanism: the competition between different Rydberg components, which plays a vital role in the stability of the time crystal phase. The paper, titled "Dissipative Time Crystal in a Strongly Interacting Rydberg Gas," was co-authored by Xiaoling Wu (2017 PhD), Zhukui Wang (2021 PhD), and Fan Yang (2015 PhD, now a postdoc at the University of Innsbruck). The corresponding authors are Xiangliang Li from the Beijing Academy of Quantum Information Sciences, Thomas Pohl from the Vienna University of Technology, and Li You. Other contributors include Ruochen Gao (2022 PhD), Chao Liang (2018 PhD), and Associate Professor Mengkun Zheng from the Department of Physics at Tsinghua University. This research was supported by the National Natural Science Foundation of China, the Ministry of Science and Technology, the State Key Laboratory of Low-Dimensional Quantum Physics at Tsinghua University, the Center for Quantum Information Frontier Sciences, the Beijing Academy of Quantum Information Sciences, and the Hefei National Laboratory. The findings not only advance the theoretical understanding of time crystals but also open new avenues for their practical applications in fields such as quantum computing and precision measurements. The ability to observe and maintain time crystals in a room-temperature environment is particularly noteworthy, as it simplifies experimental setups and potentially broadens the scope of their use in real-world scenarios.