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Experiment Shows Fundamental Nature of Extremely Small Things Isn’t Determined Until Measured, Confirming Quantum Mechanics Weirdness

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In the weird world of quantum mechanics, tiny things like electrons, photons, and even entire atoms behave as both particles and waves.In the weird world of quantum mechanics, tiny things like electrons, photons, and even entire atoms behave as both particles and waves.

Physicists at The Australian National University (ANU) have conducted an updated version of John Wheeler’s famous 1978 delayed-choice thought experiment, involving a particle which has the choice of acting like either a particle or a wave. The result is extremely weird by everyday standards, but it’s routine for people studying quantum mechanics.

Experiments done in the past couple of centuries have shown that, at really tiny scales, things behave as both waves and particles. Whether a photon or an electron behaves like a particle or a wave depends on whether it is observed or not, which is quite a puzzling fact. Over the past century, scientists have come up with a series of thought experiments, as well as real tests, in order to study and explain this peculiarity of quantum mechanics. One of the latest, which once again confirms this weird theory, was conducted at the ANU Research School of Physics and Engineering by a team lead by Associate Professor Andrew Truscott.

For the experiment, the researchers trapped a group of helium atoms into a weird, extremely cool state known as a Bose-Einstein condensate, and then ejected the atoms one by one until there was a single particle left. This was then dropped through a pair of laser beams forming a grating pattern which “splits” the particle, just like a prism or a solid grating splits a beam of light. After the atom passed through the first grating, a quantum random number generator would decide whether or not to turn on another grating which would recombine the paths.

Here’s where things get interesting. If the atom acted like a single particle, the first grating would simply make it choose one path or another, and it would subsequently be detected (as a single particle) on the other side of the setup. And that’s exactly what happens, if only the first grating is activated. However, researchers noticed that whenever the second grating was added, they detected an interference pattern as if the atom went down both paths and was now acting like a wave.

This is extremely weird, because, as I’ve mentioned, the second grating was only activated after the atom had gone through the first crossroads, at which point it should have already made the decision of whether it will act as a particle or as a wave. But, in fact, the researchers found that the atom still hasn’t made its decision until it reaches the second crossroads and is thus measured a second time. This flies in the face of what we know about cause and effect but tells us something important about the quantum world: measurement is everything! Before being observed, the atom really is both a particle and a wave at the same time, and only we measure it does it decide what we see it as. According to professor Truscott, “the atoms did not travel from A to B. It was only when they were measured at the end of the journey that their wave-like or particle-like behavior was brought into existence.” (Below is a great explanation by Looking Glass Universe of the delayed-choice quantum eraser experiment, a version of which was proposed in 1978 by John Wheeler. The ANU team was aiming to recreate this experiment, only using single atoms instead of photons.)

https://www.youtube.com/watch?v=MW-AemjSVGY

Now, of course, it’s tempting to think that since measurement plays such an important role in determining how things behave at the microscopic level, observers have a sort of privileged position in the grand scheme of things. This doesn’t mean, however, that there’s no such thing as objective reality. For one thing, the extremely bizarre phenomena we see at a quantum level don’t scale up – no object we can see acts as a wave (except, well, waves) and we are usually very good at predicting the behavior of things if we know the basic laws of physics. Experiments like this don’t show that the Universe is a single consciousness or that humans have the power to control reality – they just show that the quantum world is really weird. Nevertheless, we owe things like lasers, LEDs, and transistors to the fact that it works and, at least at some level, we understand it. Which is why this research, and its correct interpretation, is so important.

Who doesn’t enjoy listening to a good story. Personally I love reading about the people who inspire me and what it took for them to achieve their success. As I am a bit of a self confessed tech geek I think there is no better way to discover these stories than by reading every day some articles or the newspaper . My bookcases are filled with good tech biographies, they remind me that anyone can be a success. So even if you come from an underprivileged part of society or you aren’t the smartest person in the room we all have a chance to reach the top. The same message shines in my beliefs. All it takes to succeed is a good idea, a little risk and a lot of hard work and any geek can become a success. VENI VIDI VICI .

Physics

Meteorite that is billions of years old was turned into LEGO bricks for a test of a moon habitat

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Building a permanent base on the Moon out of things found there is one of the main goals for future exploration. Scientists have attempted to make bricks using a variety of materials, including blood and potatoes. Researchers from the European Space Agency (ESA) have just tried out a new method. They 3D-printed LEGO bricks from stuff that was formed in space billions of years ago. They work just like regular LEGO bricks, which means that stepping on one would still hurt.

Regolith, which is soil made of sharp rocks, covers the moon’s surface. It was formed by meteor impacts and charged particles from the sun and other places over billions of years. We don’t have that on Earth, but we can make something that looks like it by mixing it with polylactide, a bio-based polymer that breaks down naturally.

The mix was more realistic because it had a third ingredient. They ground up a meteorite that fell in North Africa in 2000 and added it to the mix. Meteorite dust is the closest thing to regolith that we have on Earth. The end result is a strong brick that looks great in space gray.

Even though the 3D printing process adds flaws that regular bricks don’t have, the space LEGO bricks work the same way as regular ones and click together. But the experiment does show that it is possible to make structures from Moon materials that can fit together. This gives us a lot of options when we think about building bases for a possible future mission.

“No one has ever built something on the Moon, so it was fun to be able to try out different designs and building methods with our space bricks.” ESA Science Officer Aidan Cowley said in a statement, “It was fun and helpful for learning about the limits of these techniques from a scientific point of view.”

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“I love creative building, and so did my team. We thought it would be fun to see if space dust could be shaped into a brick like a LEGO brick so we could try out different ways to build.” “It’s amazing, and the bricks may look a little rougher than usual, but the clutch power still works, so we can play with and test our designs,” Cowley said in a second statement.

The test will now be used to get younger people interested in science and engineering. The bricks will be on display at many LEGO stores in the US, Canada, Europe, and Australia until September 20.

“Everyone knows that scientists and engineers in the real world sometimes use LEGO bricks to test their ideas. An ESA official, Emmet Fletcher, said, “ESA’s space bricks are a great way to get young people interested in space science and show them that play and imagination are also important in space science.”

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Engineering

Testing the longest quantum network on existing fiber optics in Boston

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Imagine a world where information can be transmitted securely across the globe, free from the prying eyes of hackers. Its incredible power lies in the realm of quantum mechanics, making it a groundbreaking advancement with immense potential for the future of telecommunications. There have been obstacles to conquer, but there has also been notable progress, exemplified by a recent achievement from researchers at Harvard University.

Using the existing fiber optics within the city of Boston, the team successfully demonstrated the longest transmission between two nodes. The fiber path covered a total distance of 35 kilometers (22 miles), encircling the entire city. The two nodes that connected to the close path were situated on different floors, making the fiber route not the shortest but rather an intriguing one.

Quantum information has been successfully transmitted over longer distances, showcasing remarkable advancements in this experiment that bring us closer to the realization of a practical quantum internet. The real breakthrough lies in the nodes, going beyond the mere utilization of optical fibers.

A typical network utilizes signal repeaters made of optical fiber. These devices incorporate optical receivers, electrical amplifiers, and optical transmitters. The signal is received, transformed into an electrical form, and subsequently converted back into light before being transmitted. They play a crucial role in expanding the reach of the original signal. And in its present state, this is not suitable for quantum internet.

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The issue lies not in the technology, but rather in the fundamental principles of physics. Copying quantum information is not possible in that manner. Quantum information is highly secure due to its entangled state. The Harvard system operates by utilizing individual nodes that function as miniature quantum computers, responsible for storing, processing, and transferring information. This quantum network, consisting of only two nodes, is currently the most extensive one ever achieved, with nodes capable of such remarkable functionality.

“Demonstrating the ability to entangle quantum network nodes in a bustling urban environment is a significant milestone in enabling practical networking between quantum computers,” stated Professor Mikhail Lukin, the senior author.

At each node, a tiny quantum computer is constructed using a small piece of diamond that contains a flaw in its atomic arrangement known as a silicon vacancy center. At temperatures close to absolute zero, the silicon vacancy has the remarkable ability to capture, retain, and interconnect pieces of data, making it an ideal choice for a node.

“Given the existing entanglement between the light and the first node, it has the capability to transmit this entanglement to the second node,” elucidated Can Knaut, a graduate researcher in Lukin’s lab. “This phenomenon is known as photon-mediated entanglement.”

The study has been published in the prestigious journal Nature.

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Physics

What are the consequences of flying over an earthquake?

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Have you ever pondered the potential consequences of being aboard a commercial flight at a significant altitude when a colossal earthquake occurs? Presumably, you would be in an altered state of consciousness that would hinder your ability to perceive and comprehend any sensory experiences, correct? The answer to that question is contingent upon several factors.

Seismic activity and atmospheric conditions
Although it may appear improbable, an earthquake can potentially lead to several consequences that could pose challenges for a flight, depending on the circumstances. However, it is important to first examine the connection between the atmosphere and the earth before delving into that topic.

Attila Komjathy, a scientist at NASA’s Jet Propulsion Laboratory (JPL) of the California Institute of Technology, explained on NASA’s website that when the ground shakes, it generates small atmospheric waves that can travel all the way up to the ionosphere. This is a region known as the exosphere, which can reach a distance of up to 1,000 kilometers (600 miles) from the Earth’s surface.

Consequently, an earthquake has the potential to induce certain atmospheric disruptions, but is this sufficient to disrupt the operation of an aircraft? Simply put, the answer is no. However, if we delve deeper into the matter, the answer remains a resounding no, but with some intriguing nuances.

Earthquakes emit seismic waves, which manifest as pressure waves (P waves) and shear waves (S waves). S waves are restricted to propagating through solid media, such as the ground, while P waves have the ability to transmit through different types of media, including liquids and gases. Consequently, they have the ability to enter the atmosphere. When sound is transformed into soundwaves, they often have a frequency below 20 hertz, which is the minimum level for human hearing. Consequently, these soundwaves, known as infrasound, are usually inaudible.

Nevertheless, as these waves propagate through the air, their intensity diminishes. This phenomenon is known as attenuation, and it essentially refers to the decrease in sound intensity as the distance between the source and the listener increases. It is also a phenomenon that diminishes the intensity of sunlight as it passes through different layers of the atmosphere or other substances, such as the ocean.

Consequently, an aircraft traversing an earthquake, regardless of its intensity, would remain unaffected by the seismic vibrations beneath. Once the P waves have propagated through the rock and subsequently the air, their intensity will have significantly decreased, rendering them overshadowed by the plane’s own noise and movement.

Nevertheless, airplanes are not exempt from risks during an earthquake. The concerns at hand pertain to navigation and safety, albeit of a distinct nature.

In 2018, a self-proclaimed United States Air Force pilot and aero engineer named Ron Wagner provided a response on Quora to a question inquiring about the impact of earthquakes on an aircraft in flight. Wagner’s response was sufficiently captivating that Forbes subsequently shared it again.

Wagner claims that he piloted an aircraft during an earthquake, causing disruptions to air traffic control. During this occurrence, the earthquake resulted in a loss of electricity at the ground base, which consequently affected the plane’s navigation instruments and its capacity to communicate. The power outage resulted in the loss of radar signals for air traffic control, rendering them unable to determine the location of Wagner’s flight. Nevertheless, these problems were quickly resolved when the emergency power of the ground base was activated.

Although this may sound alarming, it serves as an illustration of potential occurrences. Typically, air traffic control stations possess ample emergency backup generators to handle such situations. In addition, they have meticulously developed contingency plans for system-wide events, which include strategies for addressing potential scenarios such as volcanic eruptions, nuclear fallout, floods, acts of terrorism, and earthquakes.

If you find yourself flying during an earthquake, you can rest assured that there is very little cause for concern. Typically, you will be unaware of the occurrence until you touch down.

All “explainer” articles undergo verification by fact-checkers to ensure their accuracy prior to publication. Information can be updated in the future by modifying, deleting, or adding text, images, and links.

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