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作者：李言 来源：科学网微信公众号 发布时间：2025/5/24 20:33:59
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编译|李言
Nature, 22 May 2025, Volume 641 Issue 8064
《自然》2025年5月22日，第641卷，8064期
Tunable vacuum-field control of fractional and integer quantum Hall phases
分数和整数量子霍尔相的可调控真空场控制
理论分析表明，这些效应源于强真空电场梯度区域内由虚拟腔光子介导的有效长程吸引相互作用。
研究发现揭示了腔真空场重塑量子霍尔系统电子关联的新机制，为调控低维材料中的关联量子相提供了新方法，并为在紧凑型器件中实现可调控的多体相互作用开辟了新途径。
▲ Abstract： Here we demonstrate that adjusting the coupling strength between a two-dimensional electron gas and the vacuum fields of a hovering split-ring resonator leads to a significant reduction in exchange splitting at odd-integer filling factors, along with an enhancement of fractional quantum Hall gaps at filling factors 4/3, 5/3 and 7/5. Theoretical analysis indicates that these effects stem from an effective long-range attractive interaction mediated by virtual cavity photons in regions with strong vacuum electric field gradients. Our findings uncover a new mechanism by which cavity vacuum fields can reshape electronic correlations in quantum Hall systems, establishing a new approach for manipulating correlated quantum phases in low-dimensional materials and paving the way for engineering tailored many-body interactions in compact devices.
Large gas inflow driven by a matured galactic bar in the early Universe
由早期宇宙中成熟星系棒所驱动的大规模气体流
研究发现J0107a星系棒的气体分布与运动模式与近域宇宙中的星系棒完全一致。该星系棒同时驱动着显著超越盘面旋转的非圆周运动，以每年约600个太阳质量的速率将分子气体输送至星系中心。
这一结果表明，早在111亿年前，由星系棒所驱动的动力学过程和长期演化机制就已经开始运作，在气体富集且远红外辐射强烈的巨大盘星系中，持续为活跃的恒星形成提供动力。
▲ Abstract： Here we report on a kinematic study of a galactic bar at redshift 2.467, 2.6 billion years after the Big Bang. We observed the carbon monoxide and atomic carbon emission lines of the dusty star-forming galaxy J0107a and found the bar of J0107a has gas distribution and motion in a pattern identical to local bars. At the same time, the bar drives large-scale non-circular motions that dominate over disk rotation, funnelling molecular gas into its centre at a rate of approximately 600 solar masses per year. Our results show that bar-driven dynamical processes and secular evolution were already at play 11.1 billion years ago, powering active star formation amid the gas-rich and far-infrared luminous growth phase in a massive disk galaxy.
A retrograde planet in a tight binary star system with a white dwarf
一个与白矮星构成致密双星系统的逆行行星
通过自适应光学成像技术，我们也发现伴星为一颗白矮星。对原始双星轨道参数的可信范围研究表明，双星初始最小间距为1.3天文单位，这一距离与当前行星轨道重叠，使得任何认为行星轨道与年轻恒星同期形成的假说都难以成立。
该逆行行星必然起源于环绕双星的轨道或第二代原行星盘。这一发现揭示了双星演化过程在行星系统形成与演化中的重要作用。
▲ Abstract： Here we present new radial velocity measurements that consolidate the planet hypothesis. Stable fits to all radial velocity data require the planetary orbit to be retrograde and practically coplanar. We also report the critical discovery from adaptive optics imaging that the companion star is a white dwarf. Our exploration of credible primordial binary orbital settings shows that the minimum separation between the stars was 1.3?au initially, which overlaps the current planetary orbit and makes any scenarios in which the circum-primary planetary orbit formed coevally with the young stars hardly conceivable. The retrograde planet must have originated from a circumbinary orbit or a second-generation protoplanetary disc, showing the role of binary stellar evolution in the formation and evolution of planetary systems.
A prospective code for value in the serotonin system
5-羟色胺系统中价值的预期代码
这一针对近期奖励的生物编码机制成功解释了以下现象：为何5-羟色胺神经元会受到奖励和惩罚时都能被激活，以及为何这些神经元对意外奖励表现出更强的反应，却对惩罚不存在类似的意外敏感性——这些都是既往理论未能统一的观测现象。
最终，该模型在定量预测体内神经元群体活动方面优于所有现有理论。通过调和既有理论分歧并与强化学习建立精确联系，该研究为理解5-羟色胺在学习与行为中的作用迈出了关键一步。
▲ Abstract： Merging ideas from reinforcement learning theory with recent insights into the filtering properties of the dorsal raphe nucleus, here we find a unifying perspective in a prospective code for value. This biological code for near-future reward explains why serotonin neurons are activated by both rewards and punishments, and why these neurons are more strongly activated by surprising rewards but have no such surprise preference for punishments—observations that previous theories have failed to reconcile. Finally, our model quantitatively predicts in vivo population activity better than previous theories. By reconciling previous theories and establishing a precise connection with reinforcement learning, our work represents an important step towards understanding the role of serotonin in learning and behaviour.
Exploring pathways for world development within planetary boundaries
探索在地球边界框架内的全球发展路径
结果显示：若保持当前趋势与政策，除臭氧层损耗外，所有地球边界指标到2050年都将持续恶化。实施针对性干预措施——包括履行《巴黎气候协定》、转向健康饮食结构、提升粮食与水肥利用效率——可显著缓解地球边界的逾越程度，引导人类发展转向可持续轨道（但需考虑社会与制度层面的实施可行性）。
然而即便在此情景下，由于系统惯性作用，气候变化、生物地球化学流和生物多样性等多项边界指标至2050年仍将处于逾越状态。这表明，要实现地球边界安全区内的良性发展，必须制定更有效的政策措施。
▲ Abstract： Here we use the Integrated Model to Assess the Global Environment to project control variables for eight out of nine planetary boundaries under alternative scenarios to 2050, both with and without strong environmental policy measures. The results show that, with current trends and policies, the situation is projected to worsen to 2050 for all planetary boundaries, except for ozone depletion. Targeted interventions, such as implementing the Paris climate agreement, a shift to a healthier diet, improved food, and water- and nutrient-use efficiency, can effectively reduce the degree of transgression of the planetary boundaries, steering humanity towards a more sustainable trajectory (that is, if they can be implemented based on social and institutional feasibility considerations). However, even in this scenario, several planetary boundaries, including climate change, biogeochemical flows and biodiversity, will remain transgressed in 2050, partly as result of inertia. This means that more-effective policy measures will be needed to ensure we are living well within the planetary boundaries.
High continuity of forager ancestry in the Neolithic period of the eastern Maghreb
新石器时代东马格里布地区采集者血统的高度延续性
其中，距今约8000年的突尼斯杰巴遗址个体携带欧洲狩猎采集者的遗传成分，可能反映了全新世早期通过西西里海峡的人口迁徙。
值得注意的是，东马格里布地区的新石器时代晚期人群仍保留了主要的本地采集者血统，仅混入少量欧洲农民（约距今7000年）和黎凡特群体（约距今6800年）的遗传贡献——与其他地中海新石器时代人群相比，该地区受外来基因流的影响显著更弱。
▲ Abstract： Here we present genome-wide data for nine individuals from the Later Stone Age through the Neolithic period from Algeria and Tunisia. The earliest individuals cluster with pre-Neolithic people of the western Maghreb (around 15,000–7,600 years before present (bp)), showing that this ‘Maghrebi’ ancestry profile had a substantial geographic and temporal extent. At least one individual from Djebba (Tunisia), dating to around 8,000 years bp, harboured ancestry from European hunter–gatherers, probably reflecting movement in the Early Holocene across the Strait of Sicily. Later Neolithic people from the eastern Maghreb retained largely local forager ancestry, together with smaller contributions from European farmers (by around 7,000 years bp) and Levantine groups (by around 6,800 years bp), and were thus far less impacted by external gene flow than were populations in other parts of the Neolithic Mediterranean.
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