The hunt for the ‘angel particle’ continues

A 2017 report of the discovery of a particular kind of Majorana fermion — the chiral Majorana fermion, referred to as the “angel particle” — is likely a false alarm, according to new research. Majorana fermions are enigmatic particles that act as their own antiparticle and were first hypothesized to exist in 1937. They are of immense interest to physicists because their unique properties could allow them to be used in the construction of a topological quantum computer.

A team of physicists at Penn State and the University of Wurzburg in Germany led by Cui-Zu Chang, an assistant professor of physics at Penn State studied over three dozen devices similar to the one used to produce the angel particle in the 2017 report. They found that the feature that was claimed to be the manifestation of the angel particle was unlikely to be induced by the existence of the angel particle. A paper describing the research appears on January 3, 2020 in the journal Science.

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New theory of quantum mechanics shows matter is not in the eye of the observer

The measurement problems has plagued theoretical physics for nearly 100 years

The mystery of why quantum matter jumps from a wave-like state to a well-defined particle when it is observed has puzzled scientists for nearly a 100 years.

Known as ‘the measurement problem’ it is widely seen as the major complication in quantum theory and has led even well-respected scientists to suggest that the human mind may be having some kind of telepathic influence on the fabric of the universe – our thoughts actually shaping reality around us.

But physicist Jonathan Kerr, who has studied quantum mechanics for 35 years from his cottage in Surrey, believes he has solved the riddle, and the answer is more prosaic than some might have hoped.

He thinks that it is actually impossible to measure anything without a tiny interaction taking place and it is that ‘bump’ that tells the particle where it is in space and fixes its form.

Kerr, the nephew of the late author Judith Kerr, has just published a book on his theory and an article is due to appear in a well-respected peer reviewed journal soon. The idea was first posited by some scientists in the 1990s but it has been an unfinished until now.

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Teoria quântica que diz que duas realidades podem coexistir é comprovada em experimen

A física quântica, como sabemos, é um reino totalmente diferente e estranho da física. Lá, coisas estranhas e inimagináveis no nível normal da física acontecem, como o entrelaçamento quântico e outros fenômenos. E por incrível que pareça, as coisas acabaram de ficar mais estranhas. Um experimento acaba de comprovar uma questão que tem intrigado os cientistas que estudam este campo da física há anos: será que duas versões da realidade podem existir ao mesmo tempo? Os físicos dizem que a resposta para essa pergunta é afirmativa – pelo menos no mundo quântico.

O experimento colocou em prática uma teoria: dois indivíduos observando o mesmo fóton poderiam chegar a diferentes conclusões sobre o estado desse fóton – e, no entanto, ambas as suas observações estariam corretas. Pela primeira vez, os cientistas replicaram as condições descritas neste experimento mental. Seus resultados, publicados em 13 de fevereiro, confirmaram que, mesmo quando os observadores descreviam estados diferentes no mesmo fóton, as duas realidades conflitantes poderiam ser ambas verdadeiras.

“Você pode verificar as duas”, confirma Martin Ringbauer, um dos co-autores do estudo e pesquisador de pós-doutorado do Departamento de Física Experimental da Universidade de Innsbrück, na Áustria.

Mas como isso é possível?

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Electronics at the speed of light

Illustration of how electrons can be imagined to move between two arms of a metallic nanoantenna, driven by a single-cycle light wave. Credit: University of Konstanz

A European team of researchers including physicists from the University of Konstanz has found a way of transporting electrons at times below the femtosecond range by manipulating them with light. This could have major implications for the future of data processing and computing.

Contemporary electronic components, which are traditionally based on silicon semiconductor technology, can be switched on or off within picoseconds (i.e. 10-12 seconds). Standard mobile phones and computers work at maximum frequencies of several gigahertz (1 GHz = 109 Hz) while individual transistors can approach one terahertz (1 THz = 1012Hz). Further increasing the speed at which electronic switching devices can be opened or closed using the standard technology has since proven a challenge. A recent series of experiments—conducted at the University of Konstanz and reported in a recent publication in Nature Physics—demonstrates that electrons can be induced to move at sub-femtosecond speeds, i.e. faster than 10-15 seconds, by manipulating them with tailored .

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Heat energy leaps through empty space, thanks to quantum weirdness

If you use a vacuum-insulated thermos to help keep your coffee hot, you may know it’s a good insulator because heat energy has a hard time moving through empty space. Vibrations of atoms or molecules, which carry thermal energy, simply can’t travel if there are no atoms or molecules around.

But a new study by researchers at the University of California, Berkeley, shows how the weirdness of quantum mechanics can turn even this basic tenet of classical physics on its head.

The study, appearing this week in the journal Nature, shows that can leap across a few hundred nanometers of a complete vacuum, thanks to a quantum mechanical phenomenon called the Casimir interaction.

Though this interaction is only significant on very short length scales, it could have profound implications for the design of computer chips and other nanoscale electronic components where is key. It also upends what many of us learned about heat transfer in high school physics.

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In surprise breakthrough, scientists create quantum states in everyday electronics

After decades of miniaturization, the electronic components we’ve relied on for computers and modern technologies are now starting to reach fundamental limits. Faced with this challenge, engineers and scientists around the world are turning toward a radically new paradigm: quantum information technologies.

Quantum technology, which harnesses the strange rules that govern particles at the , is normally thought of as much too delicate to coexist with the electronics we use every day in phones, laptops and cars. However, scientists with the University of Chicago’s Pritzker School of Molecular Engineering announced a significant breakthrough: Quantum states can be integrated and controlled in commonly used made from silicon carbide.

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