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Scientists at the University of Konstanz in Germany have advanced ultrafast electron microscopy to unprecedented time resolution. Reporting in Science Advances, the research team presents a method for the all-optical control, compression, and characterization of electron pulses within a transmission electron microscope using terahertz light. Additionally, the researchers have discovered substantial anti-correlations in the time domain for two-electron and three-electron states, providing deeper insight into the quantum physics of free electrons.

Ultrafast electron microscopy is a cutting-edge technique that combines the spatial resolution of traditional electron microscopy with the of ultrafast femtosecond laser pulses. This powerful combination allows researchers to observe atoms and electrons in motion, capturing dynamic processes in materials with unparalleled clarity. By visualizing these rapid events in space and time, scientists can gain deeper insights into the fundamental mechanisms that govern and transitions, helping to create advancements in research fields such as nanotechnology, optics, materials science, and .

Although ultrafast electron microscopy enables, in principle, the observation of atomic and electronic motions on fundamental spatial and temporal scales, capturing these rapid dynamics has remained challenging due to the limitations in electron pulse duration. The current standard electron pulses, lasting about 200 femtoseconds, are too long to resolve many fundamental reaction processes in materials and molecules. Pulses ten times shorter would be required to observe basic reaction paths and collective atomic motions, so-called phonon modes, in real time.

During electron-impact ionization (EII), high-energy electrons collide with atoms, knocking away one or more of their outer electrons. To calculate the probability that ionization will occur during these impacts, researchers use a quantity named the “ionization cross-section.” EII is among the main processes affecting the balance of charges in hot plasma, but so far, its cross-section has proven incredibly difficult to study through theoretical calculations.

Through new research published in The European Physical Journal D, Stefan Schippers and colleagues at Justus-Liebig University of Giessen, Germany, present new calculations for the EII cross-section, which closely match with their experimental results. Their discoveries could provide useful new insights in many fields of research where is studied, including astrophysics and controlled nuclear fusion.

So far, EII cross-sections have proven especially challenging to calculate for two key reasons: the that can emerge between the electrons involved in the process, and the wide array of possible electron configurations in the atoms being impacted.

Abstract We have analytically determined the refractive index for the mechanical refraction of a relativistic particle for its all possible speeds. We have critically analysed the importance of Descartes’ metaphysical theory and extended it in this regard. We have considered the conservation of the tangential component of the relativistic momentum and the relativistic energy of the particle in the process of the mechanical refraction within the optical-mechanical analogy. Our result for the mechanical refractive index exactly matches with the forms of both the Fermat’s result on Snell’s law of optical refraction at the ultra-relativistic limit and the Descartes’ metaphysical result on the pseudo-Snell law of optical refraction at the non-relativistic limit. Graphic abstract Mechanical refraction from medium-1 to medium-2 for $$U2U1$$ U 2 U 1.

Researchers have identified new characteristics of layered low-dimensional materials that enable rapid transfers of electrons and thermal energy, pointing to potential improvements in ultrafast optical technologies and various other applications.

In a collaborative work in the Dynacom framework (French Japanese Laboratory), recent studies have highlighted that materials composed of layered tubes, which are atomically thick and classified as low-dimensional materials, exhibit new properties. Although the static properties of these structures, such as electrical conduction, are well documented, their dynamic properties, including electron transfer between layers and atomic motion triggered by light exposure, have received less attention.

In this study, scientists constructed nested cylindrical structures by wrapping carbon nanotubes (CNTs) in boron nitride nanotubes. They then examined the motion of electrons and atoms induced by ultrashort light pulses on a one-dimensional (1D) material. Electron motion was monitored using broadband ultrafast optical spectroscopy, which captures instantaneous changes in molecular and electronic structures due to light irradiation with a precision of ten trillionths of a second (10−13 s). Atomic motion was observed through ultrafast time-resolved electron diffraction, which similarly achieved monitoring of structural dynamics with ten-trillionth-of-a-second accuracy.

The study suggests these primordial black holes could have absorbed free quarks and gluons, making them different from typical black holes formed by collapsing stars. They would be incredibly small, yet could account for much of the universe’s dark matter.


For decades, scientists have struggled to explain the lack of visible matter in the universe.

Watch more interviews on the deep laws of nature: https://shorturl.at/P6tIr Does information work at the deep levels of physics, including quantum theory, undergirding the fundamental forces and particles? But what is the essence of information—describing how the world works or being how the world works. There is a huge difference. Could information be the most basic building block of reality? Support the show with Closer To Truth merchandise: https://bit.ly/3P2ogje Follow us on Instagram for news, giveaways, announcements, and more: https://shorturl.at/dnA39 Raphael Bousso is a theoretical physicist and string theorist. He is a professor at Department of Physics, UC Berkeley. He is known for the proposal of Bousso’s holographic bound, also known as the covariant entropy bound. For members-only benefits, register for a free CTT account today: https://shorturl.at/ajRZ8 Closer To Truth, hosted by Robert Lawrence Kuhn and directed by Peter Getzels, presents the world’s greatest thinkers exploring humanity’s deepest questions. Discover fundamental issues of existence. Engage new and diverse ways of thinking. Appreciate intense debates. Share your own opinions. Seek your own answers.

Within the vast tapestry of the universe, where the microscopic building blocks of matter intertwine with the cosmic dance of galaxies, lies a story of profound discovery. Venture into a realm where the laws of physics as we know them are both challenged and confirmed, where the invisible forces that hold the very fabric of our reality together are brought into the light. This narrative isn’t born from the pages of a science fiction novel but emerges from the cutting-edge explorations at the heart of quantum physics. At this frontier, scientists embark on a rigorous inquiry to understand the origins of particle mass, revealing insights that connect the infinitesimal to the immense, from the atoms in our bodies to the distant stars.

Article 39 Why an electron does not fall into the nucleus in terms of the strong and weak nuclear forces.

Your thoughts would be appreciated.

It can be shown one may able to derive the strong and weak nuclear forces and the internal geometry of protons and neutrons in terms of the orientation of…


Electrons in the atom do enter the nucleus. In fact, electrons in the s states tend to peak at the nucleus. Electrons are not little balls that can fall into the nucleus under electrostatic attraction. Rather, electrons are quantized wavefunctions that spread out in space and can sometimes act like particles in limited ways. An electron in an atom spreads out according to its energy. The states with more energy are more spread out. All electron states overlap with the nucleus, so the concept of an electron “falling into” or “entering” the nucleus does not really make sense. Electrons are always partially in the nucleus.

The result is a significant advancement in the field, showcasing the practical applicability of quantum computing in solving complex material science problems. Furthermore, the researchers discovered factors that can improve the durability and energy efficiency of quantum memory devices. The findings have been published in Nature Communications.

In the early 1980s, Richard Feynman asked whether it was possible to model nature accurately using a classical computer. His answer was: no. The world consists of fundamental particles, described by the principles of quantum physics. The exponential growth of the variables that must be included in the calculations pushes even the most powerful supercomputers to their limits. Instead, Feynman suggested using a computer that was itself made up of . With his vision, Feynman is considered by many to be the Father of Quantum Computing.

Scientists at Forschungszentrum Jülich, together with colleagues from Slovenian institutions, have now shown that this vision can actually be put into practice. The application they are looking at is a so-called many-body system. Such systems describe the behavior of a large number of particles that interact with each other.