The upper limit of the speed of sound has been determined. Free Technical Library News

NEWS OF SCIENCE AND TECHNOLOGY, NOVELTY IN ELECTRONICS
Free technical library / timeline

An upper limit on the speed of sound has been determined

22.10.2020

An international group of scientists has calculated the value of the upper (maximum) limit of the speed of propagation of sound waves. This value turned out to be 36 kilometers per second, twice the speed of sound in diamond, the hardest known material today.

Waves, such as sound and electromagnetic waves, are vibrations that move the energy contained in them from one place to another. Sound waves can propagate in various media, in air, in water and in solids, and in each of these media the speed of sound propagation has its own value. For example, the denser the medium, the faster sound travels through it, which explains why you can learn about the approach of a train much earlier by putting your ear to the rail of the railway track.

Albert Einstein's theory of special relativity sets an absolute maximum limit on any speed limit, which is equal to the speed of light in a vacuum and is about 300 kilometers per second. However, until recently, no one knew whether there was any upper limit for the speed of propagation of sound waves.

Preliminary studies carried out by the scientists mentioned above have shown that the upper limit of the speed of sound can depend on the value of two dimensionless fundamental constants: the fine structure constant and the ratio of the mass of the proton to the mass of the electron.

These two meanings, as is already well known, play a very important role in our understanding of the nature, structure and "functioning" of the Universe. Their precisely measured values determine the course of nuclear reactions, such as the decay of protons and the processes of thermonuclear fusion, occurring in the interiors of stars. The balance between these two constants defines a narrow band of "livable zone" in which molecular structures can begin to form on the surface of planets, which are the first "glimpses" of future life.

However, the results of new research indicate that the two fundamental constants can also affect other phenomena and processes related to materials science, condensed matter physics, where their values set some limits for certain material properties, including the speed of sound in these materials. .

Scientists tested their theory on the speed of sound on a very wide range of different materials, which made it possible to confirm the assumption that as the mass of an atom increases, the speed of sound in the medium of this substance will decrease. This, in turn, implies that the highest speed of sound will be in the medium of solid atomic hydrogen. However, this form of hydrogen is produced only at very high pressures, above 1 million atmospheres, which is comparable to the pressure at the core of gas giant planets such as Jupiter. At such pressures, hydrogen becomes a solid metallic form, it has electrical conductivity and, according to some theories, is a superconductor, the critical point of which is in the range of room temperatures.

For calculations, scientists used the quantum mechanical model they created for the metallic atomic form of hydrogen. Calculations made using this model have given scientists a value for the speed of sound that is very close to the fundamental theoretical limit.

<< Back: Allen-Bradley CompactLogix 1769 programmable controller 22.10.2020

>> Forward: Energy from exhaled carbon dioxide 21.10.2020

Latest news of science and technology, new electronics:

Alcohol content of warm beer 07.05.2024

Beer, as one of the most common alcoholic drinks, has its own unique taste, which can change depending on the temperature of consumption. A new study by an international team of scientists has found that beer temperature has a significant impact on the perception of alcoholic taste. The study, led by materials scientist Lei Jiang, found that at different temperatures, ethanol and water molecules form different types of clusters, which affects the perception of alcoholic taste. At low temperatures, more pyramid-like clusters form, which reduces the pungency of the "ethanol" taste and makes the drink taste less alcoholic. On the contrary, as the temperature increases, the clusters become more chain-like, resulting in a more pronounced alcoholic taste. This explains why the taste of some alcoholic drinks, such as baijiu, can change depending on temperature. The data obtained opens up new prospects for beverage manufacturers, ... >>

Major risk factor for gambling addiction 07.05.2024

Computer games are becoming an increasingly popular form of entertainment among teenagers, but the associated risk of gaming addiction remains a significant problem. American scientists conducted a study to determine the main factors contributing to this addiction and offer recommendations for its prevention. Over the course of six years, 385 teenagers were followed to find out what factors may predispose them to gambling addiction. The results showed that 90% of study participants were not at risk of addiction, while 10% became gambling addicts. It turned out that the key factor in the onset of gambling addiction is a low level of prosocial behavior. Teenagers with a low level of prosocial behavior do not show interest in the help and support of others, which can lead to a loss of contact with the real world and a deepening dependence on virtual reality offered by computer games. Based on these results, scientists ... >>

Traffic noise delays the growth of chicks 06.05.2024

The sounds that surround us in modern cities are becoming increasingly piercing. However, few people think about how this noise affects the animal world, especially such delicate creatures as chicks that have not yet hatched from their eggs. Recent research is shedding light on this issue, indicating serious consequences for their development and survival. Scientists have found that exposure of zebra diamondback chicks to traffic noise can cause serious disruption to their development. Experiments have shown that noise pollution can significantly delay their hatching, and those chicks that do emerge face a number of health-promoting problems. The researchers also found that the negative effects of noise pollution extend into the adult birds. Reduced chances of reproduction and decreased fertility indicate the long-term effects that traffic noise has on wildlife. The study results highlight the need ... >>

Wireless speaker Samsung Music Frame HW-LS60D 06.05.2024

In the world of modern audio technology, manufacturers strive not only for impeccable sound quality, but also for combining functionality with aesthetics. One of the latest innovative steps in this direction is the new Samsung Music Frame HW-LS60D wireless speaker system, presented at the 2024 World of Samsung event. The Samsung HW-LS60D is more than just a speaker system, it's the art of frame-style sound. The combination of a 6-speaker system with Dolby Atmos support and a stylish photo frame design makes this product the perfect addition to any interior. The new Samsung Music Frame features advanced technologies including Adaptive Audio that delivers clear dialogue at any volume level, and automatic room optimization for rich audio reproduction. With support for Spotify, Tidal Hi-Fi and Bluetooth 5.2 connections, as well as smart assistant integration, this speaker is ready to satisfy your ... >>

A New Way to Control and Manipulate Optical Signals 05.05.2024

The modern world of science and technology is developing rapidly, and every day new methods and technologies appear that open up new prospects for us in various fields. One such innovation is the development by German scientists of a new way to control optical signals, which could lead to significant progress in the field of photonics. Recent research has allowed German scientists to create a tunable waveplate inside a fused silica waveguide. This method, based on the use of a liquid crystal layer, allows one to effectively change the polarization of light passing through a waveguide. This technological breakthrough opens up new prospects for the development of compact and efficient photonic devices capable of processing large volumes of data. The electro-optical control of polarization provided by the new method could provide the basis for a new class of integrated photonic devices. This opens up great opportunities for ... >>

Random news from the Archive

Water can have several liquid states 21.11.2020

Scientists have experimentally proved that supercooled water can exist in the form of two immiscible liquid phases with different densities. The research results are published in the journal Science.

Water is one of the most common substances. At the same time, it has unique physical properties - when pressure and temperature change, it behaves differently from other liquids. Anomalies of the phase states of water have been studied by physicists and chemists all over the world for many years.

Everyone is familiar with the usual liquid state of water at normal temperature. However, thirty years ago, scientists suggested that at ultra-low temperatures, water could have several liquid states.

Researchers from the United States, Canada, Sweden and South Korea, led by Nicolas Giovambattista, professor at the City University of New York and head of the Department of Physics at Brooklyn College, have experimentally proved that at minus 63 degrees Celsius, water can exist at low pressure as a liquid with low density, and at high - in the form of a liquid with a high density.

These two liquids have markedly different properties - they differ in density by 20 percent and, under appropriate conditions, do not mix with each other, like oil and water.

The counterintuitive hypothesis has been one of the most important questions in the chemistry and physics of water from the very beginning. This is because experiments in which two liquid states can be obtained at once are very difficult due to the seemingly inevitable formation of ice under conditions where two liquids should theoretically exist.

See full Archive of science and technology news, new electronics

All languages of this page

Home page | Library | Articles | Website map | Site Reviews