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Electronegativity is one of the most well-known models for explaining why chemical reactions occur. Now, Martin Rahm from Chalmers University of Technology, Sweden, has redefined the concept with a new, more comprehensive scale. His work, undertaken with colleagues including a Nobel Prize-winner, has been published in the Journal of the American Chemical Society.

The theory of is used to describe how strongly different atoms attract electrons. By using electronegativity scales, one can predict the approximate charge distribution in different molecules and materials, without needing to resort to complex quantum mechanical calculations or spectroscopic studies. This is vital for understanding all kinds of materials, as well as for designing new ones. Used daily by chemists and materials researchers all over the world, the concept originates from Swedish chemist Jöns Jacob Berzelius’ research in the 19th century and is widely taught at high-school level.

Now, Martin Rahm, Assistant Professor in Physical Chemistry at Chalmers University of Technology, has developed a brand-new scale of electronegativity.

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The production of entropy, which means increasing the degree of disorder in a system, is an inexorable tendency in the macroscopic world owing to the second law of thermodynamics. This makes the processes described by classical physics irreversible and, by extension, imposes a direction on the flow of time. However, the tendency does not necessarily apply in the microscopic world, which is governed by quantum mechanics. The laws of quantum physics are reversible in time, so in the microscopic world, there is no preferential direction to the flow of phenomena.

One of the most important aims of contemporary scientific research is knowing exactly where the transition occurs from the quantum world to the classical world and why it occurs — in other words, finding out what makes the production of entropy predominate. This aim explains the current interest in studying mesoscopic systems, which are not as small as individual atoms but nevertheless display well-defined quantum behavior.

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A scientific collaboration has released a concept design for the Large Hadron Collider’s successor, an enormous new experiment that would sit inside a hundred-kilometer (62-mile) tunnel.

The design concept plans for two Future Circular Colliders, the first which would begin operation perhaps in 2040. The ambitious experiments would hunt for new particles with collision energies 10 times higher than those created by the Large Hadron Collider (LHC). The concept design is the first big milestone achieved by the scientific collaboration.

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Australia’s New South Wales scientists have adapted single atom technology to build 3D silicon quantum chips – with precise interlayer alignment and highly accurate measurement of spin states. The 3D architecture is considered a major step in the development of a blueprint to build a large-scale quantum computer.

They aligned the different layers in their 3D device with nanometer precision – and showed they could read out qubit states with what’s called ‘single shot’, i.e. within one single measurement, with very high fidelity.

“This 3D device architecture is a significant advancement for atomic qubits in silicon,” says Professor Simmons.

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One mysterious number determines how physics, chemistry and biology work. But controversial experimental hints suggest it’s not one number at all.

By Michael Brooks

IT IS a well-kept secret, but we know the answer to life, the universe and everything. It’s not 42 – it’s 1/137.

This immutable number determines how stars burn, how chemistry happens and even whether atoms exist at all. Physicist Richard Feynman, who knew a thing or two about it, called it “one of the greatest damn mysteries of physics: a magic number that comes to us with no understanding”.

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While our choices and beliefs don’t often make sense or fit a pattern on a macro level, at a “quantum” level, they can be predicted with surprising accuracy.


The irrationality of how we think has long plagued psychology. When someone asks us how we are, we usually respond with “fine” or “good.” But if someone followed up about a specific event — “How did you feel about the big meeting with your boss today?” — suddenly, we refine our “good” or “fine” responses on a spectrum from awful to excellent.

In less than a few sentences, we can contradict ourselves: We’re “good” but feel awful about how the meeting went. How then could we be “good” overall? Bias, experience, knowledge, and context all consciously and unconsciously form a confluence that drives every decision we make and emotion we express. Human behavior is not easy to anticipate, and probability theory often fails in its predictions of it.

Enter quantum cognition : A team of researchers has determined that while our choices and beliefs don’t often make sense or fit a pattern on a macro level, at a “quantum” level, they can be predicted with surprising accuracy. In quantum physics, examining a particle’s state changes the state of the particle — so too, the “observation effect” influences how we think about the idea we are considering.

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