Lifeboat Foundation

Scientists have measured the shortest unit of time ever: the time it takes a light particle to cross a hydrogen molecule.

That time, for the record, is 247 zeptoseconds. A zeptosecond is a trillionth of a billionth of a second, or a decimal point followed by 20 zeroes and a 1.

Previously, researchers had dipped into the realm of zeptoseconds; in 2016, researchers reporting in the journal Nature Physics used lasers to measure time in increments down to 850 zeptoseconds.

Recently, researchers from the Institute of Intelligent Machines developed a new wavelength selection algorithm based on combined moving window (CMW) and variable dimension particle swarm optimization (VDPSO) algorithm.

CMW retained the advantages of the moving window algorithm, and different windows could overlap each other to realize automatic optimization of spectral interval width and number. VDPSO algorithms improved the traditional particle swarm optimization (PSO) algorithm.

This new algorithm, which is called VDPSO-CMW, could search the data space in different dimensions, and reduce the risk of limited local extrema and over fitting.

Scientists have measured the shortest unit of time ever, the time it takes for a particle of light to cross a hydrogen molecule.

We only ever experience three spatial dimensions, but quantum lab experiments suggest a whole new side to reality – weird particle apparitions included.

Have you ever been in more than one place at the same time? If you’re much bigger than an atom, the answer will be no.

But atoms and particles are governed by the rules of quantum mechanics, in which several different possible situations can coexist at once.

Continue reading “Could Schrödinger’s cat exist in real life? Our research may soon provide the answer” »

Light is incredible. You can bend it, you can bounce it, and researchers have now found a way to trap light, physically move it, and then release it again.

This incredible feat of physics was demonstrated at the Johannes Gutenberg University Mainz and published in Physics Review Letters. Researchers trapped light in a quantum memory, a cloud of ultra-cold rubidium atoms. The quantum memory was then moved 1.2 millimeters and the light was released with little impact on its properties.

“We stored the light by putting it in a suitcase so to speak, only that in our case the suitcase was made of a cloud of cold atoms. We moved this suitcase over a short distance and then took the light out again. This is very interesting not only for physics in general, but also for quantum communication because light is not very easy to ‘capture’, and if you want to transport it elsewhere in a controlled manner, it usually ends up being lost,” senior author Professor Patrick Windpassinger said in a statement.

A team of German physicists managed to pack up light — and unpack it 1.2 millimeters away, without altering it in the process.

It’s a simple concept, but extremely difficult to actually pull off. To do it, the team from the Johannes Gutenberg University Mainz (JGU) had to cool down rubidium-87 atoms to almost absolute zero.

“We stored the light by putting it in a suitcase so to speak, only that in our case the suitcase was made of a cloud of cold atoms,” Patrick Windpassinger, professor at JGU, research lead, said in a statement. “We moved this suitcase over a short distance and then took the light out again.”

A team of physicists led by Professor Patrick Windpassinger at Johannes Gutenberg University Mainz (JGU) has successfully transported light stored in a quantum memory over a distance of 1.2 millimeters. They have demonstrated that the controlled transport process and its dynamics has only little impact on the properties of the stored light. The researchers used ultra-cold rubidium-87 atoms as a storage medium for the light as to achieve a high level of storage efficiency and a long lifetime.

“We stored the light by putting it in a suitcase so to speak, only that in our case the suitcase was made of a cloud of cold atoms. We moved this suitcase over a short distance and then took the light out again. This is very interesting not only for physics in general, but also for quantum communication, because light is not very easy to ‘capture’, and if you want to transport it elsewhere in a controlled manner, it usually ends up being lost,” said Professor Patrick Windpassinger, explaining the complicated process.

The controlled manipulation and storage of quantum information as well as the ability to retrieve it are essential prerequisites for achieving advances in quantum communication and for performing corresponding computer operations in the quantum world. Optical quantum memories, which allow for the storage and on-demand retrieval of quantum information carried by light, are essential for scalable quantum communication networks. For instance, they can represent important building blocks of quantum repeaters or tools in linear quantum computing. In recent years, ensembles of atoms have proven to be media well suited for storing and retrieving optical quantum information. Using a technique known as electromagnetically induced transparency (EIT), incident light pulses can be trapped and coherently mapped to create a collective excitation of the storage atoms. Since the process is largely reversible, the light can then be retrieved again with high efficiency.

Circa 2018

If you’ve been a grunt, then you probably have a love-hate relationship with body armor. You love having it in a firefight — it can save your life by stopping or slowing bullets and fragments — but you hate how heavy it is — it’s often around 25 pounds for the armor and outer tactical vest (more if you add the plate inserts to stop up to 7.62mm rounds). It’s bulky — and you really can’t move as well in it. In fact, in one firefight, a medic removed his body armor to reach wounded allies, earning a Distinguished Service Cross.