Particles near absolute zero do not break the laws of physics after all

May 20, 2014

In theory, the laws of physics are absolute. However, when it comes to the laws of thermodynamics—the science that studies how heat and temperature relate to energy—there are times where they no longer seem to apply. In a paper recently published in the European Physical Journal B, Robert Adamietz from the University of Augsburg, Germany, and colleagues have demonstrated that a theoretical model of the environment's influence on a particle does not violate the third law of thermodynamics, despite appearances to the contrary. These findings are relevant for systems at the micro or nanometer scale that are difficult to decouple from the heat or the quantum effects exerted by their environment.

The authors focused on a model system favored by experts that consists of a free particle strongly coupled to a heat bath, representing the effect of its environment. Studies of such systems typically focus on how much energy is needed to raise their temperature by a certain amount, or so-called specific heat. Previous theoretical predictions suggested that, under certain circumstances, the specific heat can decrease below zero at a temperature of strictly zero (−273.15°C). This prediction appears to breach the third law of thermodynamics, which states that the specific heat must drop to zero value at strictly zero .

The authors demonstrated that the third law of thermodynamics is not actually violated. In fact, a real particle will always be confined to a finite volume—even if that volume may be extremely large. Therefore, they discovered that previous studies need to be modified in order to account for a spatial confinement of the particle. The new model demonstrates how the negative specific heat for a truly free particle is related to a dip in the specific heat, which should be observable in the presence of a confinement.

Explore further: Nanoscale heat engine exceeds standard efficiency limit

More information: R. Adamietz, G.-L. Ingold, and U. Weiss (2014), Thermodynamic anomalies in the presence of general linear dissipation: from the free particle to the harmonic oscillator, European Physical Journal B, DOI: 10.1140/epjb/e2014-50125-2

add to favorites email to friend print save as pdf

Related Stories

Quantum engines must break down

Jun 26, 2013

Our present understanding of thermodynamics is fundamentally incorrect if applied to small systems and needs to be modified, according to new research from University College London (UCL) and the University of Gdańsk. The ...

Nanoscale heat engine exceeds standard efficiency limit

Jan 27, 2014

(Phys.org) —In 2012, a team of physicists from Germany proposed a scheme for realizing a nanoscale heat engine composed of a single ion. Like a macroscale heat engine, the theoretical nanoscale version c ...

Nanoscale heat flow predictions

May 07, 2014

Physicists are now designing novel materials with physical properties tailored to meet specific energy consumption needs. Before these so-called materials-by-design can be applied, it is essential to understand their characteristics, ...

Recommended for you

Hide and seek: Sterile neutrinos remain elusive

16 hours ago

The Daya Bay Collaboration, an international group of scientists studying the subtle transformations of subatomic particles called neutrinos, is publishing its first results on the search for a so-called ...

Novel approach to magnetic measurements atom-by-atom

21 hours ago

Having the possibility to measure magnetic properties of materials at atomic precision is one of the important goals of today's experimental physics. Such measurement technique would give engineers and physicists an ultimate ...

Scientists demonstrate Stokes drift principle

Oct 01, 2014

In nature, waves – such as those in the ocean – begin as local oscillations in the water that spread out, ripple fashion, from their point of origin. But fans of Star Trek will recall a different sort of wave pattern: ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Z99
not rated yet May 20, 2014
Sorry? Which "certain circumstances" have the temperature as being 0 K (or less)?
Since T can never be 0 K, what violation occurs at 0 K? Wow. Next they'll be saying that they've discovered (theoretically) that mass traveling at the speed of light doesn't contradict the Special Theory of Relativity. Huh?!