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Kudos Project:现在是时候了:重新审视“姆潘巴效应“

已有 1014 次阅读 2021-8-26 11:19 |系统分类:论文交流

It’s about time: Revisiting the Mpemba effect

现在是时候了:重新审视“姆潘巴效应"

 

Project DOI: 10.26303/30fe-t430

 

Kudos project 的链接:

https://www.growkudos.com/projects/its-about-time-revisiting-the-mpemba-effect

 

What is it about?

这个科研项目是关于什么的?

 

The “Mpemba effect” describes the phenomenon in which hot water appears to freeze faster than cold water. Descriptions of the effect date back to the writings of Aristotle. While modern scientists have ventured explanations for the Mpemba effect and variations thereof, the legitimacy of the effect has often been called into question. Reasons for this include the inability to reproduce the effect consistently across experiments and variations in how the primary outcome is defined (e.g., freezing vs. cooling to a certain temperature).
“姆潘巴效应”描述了热水比冷水结冰更快的现象。对这种效应的描述可以追溯到亚里士多德的著作。当现代科学家尝试解释姆潘巴效应及其变化时,这种效应是否存在经常受到质疑。其原因包括无法在实验中一致地再现效果,以及主要结果的定义(例如,冷冻vs.冷却到某一温度)存在差异。


Jian’an Wang, former professor of physics at Shenzhen University, offers a new explanation based on analyzing the relationship between time and velocity in his modified special relativity, the relationship between time and gravitational field in general relativity, the gravitational redshift and the blackbody radiation theorem.

深圳大学前物理教授王建安在基于分析其修正的狭义相对论中的时间与速度的关系、广义相对论的时间与引力场的关系、引力红移和黑体辐射定理的基础上,提出了一种新的解释。

 

According to Wang, increasing the temperature of an object has the same effect as reducing the intensity of the gravitational field,both can increase the frequency of radiation photons and speed up the time on the object.

王博士认为,提高物体的温度与降低引力场强度具有相同的效果,两者都可以增加辐射光子的频率,并加快物体上的时间。

 

Using the above conclusion on the nature of time, Wang analyzed the Mpamba effect and gave an explanation: the reason why hot water froze first than cold water is that the time on hot water is faster than on cold water.

应用以上关于时间本质的结论王博士分析了"姆潘巴效应"并给出了一个合理的解释:热水比冷水先结冰的原因是热水上的时间比冷水上的流逝得更快。

 

Jian’an Wang received his bachelor’s degree in experimental nuclear physics in 1982 from the Department of Modern Physics at the University of Science and Technology of China. Upon graduating, he was assigned to the China Institute of Atomic Energy, where he studied nuclear reactions of charged particles. In 1985, he was admitted to the Department of Physics at Huazhong University of Science and Technology, from which he received a master’s degree. He obtained a Ph.D. in 1996 from McGill University in Montreal, Quebec, Canada, for his research on laser luminescent materials. Wang entered the Department of Physics at Shenzhen University as an assistant professor in 1999 and retired in 2012. 

王建安1982年毕业于中国科学技术大学近代物理系实验核物理专业,获学士学位。毕业后,他被分配到中国原子能研究院从事带电粒子核反应研究工作。1985年考入华中科技大学物理系读研,并在那获得硕士学位。1996年,他在位于加拿大魁北克省蒙特利尔市的麦吉尔大学获得博士学位,博士论文是关于激光发光材料方面的研究。1999年进入深圳大学物理系担任副教授,并于2012年提前退休。

Why is it important?

为什么这一科研项目很重要?

 

Definitive and reproducible demonstrations of the Mpemba effect are still lacking. And it’s unclear whether a valid explanation of the phenomenon would be trivial or groundbreaking.

关于"姆潘巴效应"的明确和可重复的证明仍然缺乏。目前还不清楚对这一现象的有效解释是微不足道的还是具有开创性的。

 

Regardless, the reported effect has inspired creative thinking on the part of numerous scientists and will likely to continue to capture the imagination of scientists and science enthusiasts alike.

无论如何,报道的效应激发了许多科学家的创造性思维,并可能继续抓住科学家和科学爱好者的想象力。

 

Audience Briefings

观众简报

 

Press 新闻

 

Hot clocks run fast

温度高的钟走得快


July 30, 2021 – China – Clocks help keep our busy lives in synch and on schedule. But throughout our day, we can’t help but feel that time is often subjective.

2021年7月30日——中国——时钟帮助我们忙碌的生活保持同步和准时。但在我们的一天中,我们忍不住觉得时间往往是主观的。

 

Sometimes it seems to fly. Sometimes it undoubtedly drags.

有时它似乎能飞起来。有时它无疑会走得很慢。


Thanks to Einstein's theory of special relativity and general relativity. We now know that time is not subjective, but is related to the velocity of the object and the strength of the gravitational field in the space in which it is located.

多亏了爱因斯坦的狭义相对论和广义相对论, 我们现在知道时间不是主观的,是与物体的运动速度和所处空间的引力场强度有关的。

 

The faster the object is moving the slower time on the object, the stronger the gravitational field in the space in which the object is located the slower time on the object.

物体运动速度越快物体上的时间越慢,物体所处空间的引力场越强物体上的时间越慢。

 

It follows that space and time are inextricably linked. Massive or fast-moving objects experience time differently than do low-mass or slow-moving objects.

由此可知,空间和时间是不可分割地联系在一起的。大质量或快速移动的物体与小质量或缓慢移动的物体对时间的体验是不同的。

 

Massive or faster things run on a slower clock. While these differences in time perception have been registered on earth, it's usually been with the aid of advanced instruments like atomic clocks.

大质量或运动更快的物体运行在更慢的时钟上。借助原子钟等先进仪器的帮助,这些时间感知上的差异在地球上已经被记录下来。

 

Now, a recent preprint suggests that you might also find the same bizarre physics at work in your freezer.

最近的一份预印本表明,你可能还会在冰箱里发现同样的奇怪物理现象(时间差异)。

 

Jian'an Wang, former professor at Shenzhen University, suggests that the fickleness of time could help explain the well-known “Mpemba effect,” the observation that in certain cases hot water freezes faster than cold water.

深圳大学前教授王建安认为,时间的变化无常有助于解释著名的“潘巴效应”,即在某些情况下热水比冷水结冰更快。

 

The effect is named after Erasto Bartholomeo Mpemba. When he was a student in Tanzania in the 1960s, with the help of a physics professor, he verified the bizarre phenomenon that his hot ice cream mixture froze faster than a cold one. But descriptions of the phenomenon date as far back as the writings of Aristotle.

这一效应以Erasto Bartholomeo Mpemba的名字命名。20世纪60年代,当他还是坦桑尼亚的一名学生时,他在一位物理学教授的帮助下,验证了他的热冰淇淋混合物比冷冰淇淋混合物结冰得更快这一奇异现象。但是对这一现象的描述可以追溯到亚里士多德的著作。

 

Since then, numerous scientists have ventured an explanation, including big names such as Francis Bacon, René Descartes, and Joseph Black. While the very existence of the effect has been called into question throughout the years, a recent experiment by Avinash Kumar and John Bechhoefer from Simon Fraser University involving glass beads as stand-ins for water molecules offers up the most definitive evidence for the legitimacy of the Mpemba effect.

从那时起,包括弗朗西斯·培根、René笛卡儿和约瑟夫·布莱克等大科学家在内的众多科学家都提出了一种解释。尽管多年来这种效应的存在一直受到质疑,但西蒙弗雷泽大学(Simon Fraser University)的阿维纳什·库马尔(Avinash Kumar)和约翰·贝赫霍费尔(John Bechhoefer)最近进行的一项实验,为潘巴效应的存在提供了最明确的证据,实验中他们用玻璃珠代替了水分子。

 

That comes as no surprise to Wang, whose re-couching of Einstein’s mathematics in terms of an energy background he calls “ether” chimes well with observations of the Mpemba effect.

这对王博士来说并不奇怪,他将爱因斯坦的数学重新表述为一种他称之为“以太”的能量背景,这与他对姆巴效应的观察非常吻合。

 

This ether, according to Wang, accounts for all the classically odd features produced by special relativity: the increase in mass of moving objects, the apparent invariance of the speed of light, size contraction, and most relevantly, time dilation.

王博士认为,这种以太解释了狭义相对论产生的所有经典的奇异特征: 运动物体质量的增加、光速的表观不变性、尺寸的收缩,以及(与姆潘巴效应)最相关的时间膨胀。

 

Wang suggested that time on a moving object slows down because an increase in the speed of the moving object relative to the ether (energy) leads to an increase in the kinetic energy of the moving object, the energy density of the space around the object, which slows down time on the object.

王博士认为,运动物体上的时间之所以会变慢是因为运动物体相对以太(能量)运动速度的增加会导致运动物体动能的增加,也就是物体周围空间能量密度的增加,由此导致物体上的时间变慢。

 

Time slows down on a moving object in the same way that time slows down on an object in a gravitational field. That is, the higher the energy density in space, the slower the time on an object in space.

运动物体上的时间会变慢与处在引力场中的物体时间会变慢是同一个道理。即空间能量密度越高处在空间中的物体上的时间越慢。

 

By analyzing the law of blackbody radiation, Wang further believes that increasing the temperature of an object and reducing the energy density of the space in which the object is located have the same effect, that is, both can accelerate the time on the object.

王博士通过分析黑体辐射定律,进一步认为,增加物体的温度与降低物体所处空间的能量密度效果是相同的即都可加快物体上的时间。

 

From this, Wang obtained a relation between time and absolute temperature, that is, when an object radiates energy outward, the time on the object is proportional to the fourth power of the absolute temperature of the object:

由此王博士得出了一个时间与绝对温度的关系式,即当物体向外辐射能量时,物体上的时间与物体的绝对温度的四次方成正比:

image.png

where t’ is the time on the object, μ is a constant, σ is the Stefan-Boltzmann constant, T is the absolute temperature.

 

上式中 t'是物体上的时间,μ 是常数,σ 是Stefan-Boltzmann常数,T 是绝对温度。

 

So, hotter objects would seem to experience a faster time flow than cooler objects and therefore reach equilibrium with its surroundings (i.e., freeze inside a freezer) faster.

因此,热的物体似乎会比冷的物体经历更快的时间流动,从而更快地与周围环境达到平衡(也就是在冰箱里冷冻)。

 

While experiments are needed to test this theory, it could apply to much less mundane phenomena than those found in the kitchen.

虽然需要进行实验来验证这一理论,但这一理论可能适用于比在厨房里发现的更不那么平凡的自然现象。

 

Wang notes a link between his theory and the physics of our expanding universe—specifically, the luminescence of celestial bodies such as quasars and stars and planetary cooling.

王博士指出,他的这一理论和我们不断膨胀的宇宙的物理学之间的联系——特别是,类星体和恒星等天体的发光(寿命)以及行星(地球)的冷却(冰河期)。

 

Who is involved?

涉及哪些人?

 

Vivien Pinner and Dr. Jian’an wang

Vivien Pinner 和王建安博士

 

Kudos project 的链接:

https://www.growkudos.com/projects/its-about-time-revisiting-the-mpemba-effect 




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