BLOGS

Topics: Applied Physics, Atmospheric Science, Existentialism, Futurism, Lasers, Robotics, Science Fiction

"Laser" is an acronym for Light Amplification by the Stimulated Emission of Radiation. As the article alludes to, the concept existed before the actual device. We have Charles Hard Townes to thank for his work on the Maser (Microwave Amplification by the Stimulated Emission of Radiation) and the Laser. He won the Nobel Prize for his work in 1964. In a spirit of cooperation remarkable for the Cold War era, he was awarded the Nobel with two Soviet physicists, Aleksandr M. Prokhorov and Nikolay Gennadiyevich Basov. He lived from 1915 - 2015. The Doomsday Clock was only a teenager, born two years after the end of the Second World War. As it was in 2023, it is still 90 seconds to midnight. I'm not sure going "Buck Rogers" on the battlefield will dial it back from the stroke of twelve. Infrared lasers are likely going to be deployed in any future battle space, but infrared is invisible to the human eye, a weapon for which you only need a power supply and not an armory; it might appeal not only to knock drones out of the sky, but to assassins, contracted by governments who can afford such a powerful device, that will not leave a ballistic fingerprint, or depending on the laser's power: DNA evidence.

Nations around the world are rapidly developing high-energy laser weapons for military missions on land and sea, and in the air and space. Visions of swarms of small, inexpensive drones filling the skies or skimming across the waves are motivating militaries to develop and deploy laser weapons as an alternative to costly and potentially overwhelmed missile-based defenses.

Laser weapons have been a staple of science fiction since long before lasers were even invented. More recently, they have also featured prominently in some conspiracy theories. Both types of fiction highlight the need to understand how laser weapons actually work and what they are used for.

A laser uses electricity to generate photons, or light particles. The photons pass through a gain medium, a material that creates a cascade of additional photons, which rapidly increases the number of photons. All these photons are then focused into a narrow beam by a beam director.

In the decades since the first laser was unveiled in 1960, engineers have developed a variety of lasers that generate photons at different wavelengths in the electromagnetic spectrum, from infrared to ultraviolet. The high-energy laser systems that are finding military applications are based on solid-state lasers that use special crystals to convert the input electrical energy into photons. A key aspect of high-power solid-state lasers is that the photons are created in the infrared portion of the electromagnetic spectrum and so cannot be seen by the human eye.

Based in part on the progress made in high-power industrial lasers, militaries are finding an increasing number of uses for high-energy lasers. One key advantage for high-energy laser weapons is that they provide an “infinite magazine.” Unlike traditional weapons such as guns and cannons that have a finite amount of ammunition, a high-energy laser can keep firing as long as it has electrical power.

The U.S. Army is deploying a truck-based high-energy laser to shoot down a range of targets, including drones, helicopters, mortar shells and rockets. The 50-kilowatt laser is mounted on the Stryker infantry fighting vehicle, and the Army deployed four of the systems for battlefield testing in the Middle East in February 2024.

High-energy laser weapons: A defense expert explains how they work and what they are used for, Iain Boyd, Director, Center for National Security Initiatives, and Professor of Aerospace Engineering Sciences, University of Colorado Boulder

A laser fusion power plant proposed by Longview Fusion Energy Systems would generate 1000 MWh or more of electricity. The plant would compress fusion fuel by using an indirect drive, the same approach used at the National Ignition Facility, which in December announced that it had produced ignition and gain, the first time that fusion researchers have attained those milestones.

Topics: Futurism, Lasers, Modern Physics, Nuclear Fusion

The attainment of fusion ignition and energy gain on the world’s most energetic laser late last year was indisputably a major scientific accomplishment. But the road to fusion as a viable source of energy will be a long one, if not a dead end. And if it does ultimately become a reality, most experts say that it is unlikely that a laser-driven fusion power plant will be based on the approach taken by the National Ignition Facility (NIF), where the fusion milestone occurred.

The December shot, which produced 1.5 times the 2 MJ of energy that was fired on the fusion fuel, has silenced skeptics who said that ignition could never be created by bombarding tiny capsules of deuterium–tritium fuel with lasers. (See “National Ignition Facility surpasses long-awaited fusion milestone,” Physics Today online, 13 December 2022.) “They have done something very important: demonstrating ignition and burn,” says Stephen Bodner, a retired head of the laser fusion branch at the US Naval Research Laboratory who once was a persistent critic of NIF’s approach.

And the milestone is likely to open the floodgates to new investments in the handful of startups that are pursuing inertial fusion energy (IFE). “I think you will see a proliferation of companies devoted to IFE or aspects of IFE because of this and because of investor interest,” says Todd Ditmire, a University of Texas at Austin physicist who is chief technology officer of Focused Energy, an IFE startup.

Yet despite the fanfare greeting the announcement, the fact is that the fusion energy yield from the successful shot amounted to less than 1% of the 300 MJ taken from the electricity grid to power NIF’s 192 beams. And the energy released was enough to boil about 10 tea kettles. Many experts say that economically viable fusion will require fusion reactions yielding energy gains of at least 100 times the energy deposited on the fuel capsule—two orders of magnitude greater than the NIF shot.

NIF success gives laser fusion energy a shot in the arm, David Kramer, Physics Today

(Credit: Evgeniyqw/Shutterstock)

Topics: Astronautics, Climate Change, Environment, Futurism, Global Warming, Mars, Spaceflight

When Elon Musk founded SpaceX in 2002, he envisioned a greenhouse on Mars, not unlike the one later depicted in the 2015 blockbuster The Martian. Soon, his fantasy grew from a small-scale botanical experiment into a vision for a self-sustaining Martian city. In a speech at the 67th International Astronautical Congress in 2016, he argued his point. “History is going to bifurcate along with two directions. One path is we stay on earth forever and then there will be some eventual extinction event,” Musk says. “The alternative is to become a space-faring civilization and a multi-planet species, which, I hope you would agree, is the right way to go.”

Though Musk later clarified that the extinction event he referenced may take place millennia (or even eons) in the future, the conditions on earth today are becoming increasingly dangerous for human beings. Deadly heatwaves, food insecurity, and catastrophic natural disasters are a few of the hazards that we face as the planet continues to warm. Unfortunately, the Red Planet is a very long way from becoming a viable alternative home. While we measure carbon dioxide concentrations in parts per million on earth, Mars’ atmosphere contains 96% CO2, just one of a litany of logistical nightmares that Martian colonists would have to overcome.

In a perfect world, Musks’ dreams of extraterrestrial civilization could coexist with the eco-forward values that have driven ventures like Tesla’s solar program. But while SpaceX’s aspirations are in space, its operations have an undeniable impact at home. Unlike a Tesla sports car, SpaceX’s rockets aren’t propelled by electricity — they burn kerosene. 

Carbon emissions from space launches are dwarfed by other sources of greenhouse gasses, but they could have an outsized impact on climate. The reason for this stems from one particular product of rocket propulsion: black carbon. These tiny chunks of crystalline carbon atoms are short-lived in the atmosphere, but highly absorptive of sunlight. On the Earth’s surface, black carbon from diesel, coal, and wood combustion poses a threat to environmental and public health, particularly in developing countries. But in the upper atmosphere, rocket engines are the sole source of black carbon. For years, scientists have warned that these emissions could have unpredictable effects on climate. Still, research on the topic has been frustratingly slow.

“We identified the issue with black carbon in 2010,” says Darin Toohey, an atmospheric scientist at the University of Colorado Boulder. “The story comes and goes, but the basic players remain the same.”

Efforts to Colonize Mars Could Have a Negative Impact on Global Health, Gabe Allen, Discover Magazine

Topics: Futurism, Materials Science, Nanotechnology

The National Nanotechnology Initiative promised a lot. It has delivered more.

We’re now more than two decades out from the initial announcement of the National Nanotechnology Initiative (NNI), a federal program from President Bill Clinton founded in 2000 to support nanotechnology research and development in universities, government agencies, and industry laboratories across the United States. It was a significant financial bet on a field that was better known among the general public for science fiction than scientific achievement. Today it’s clear that the NNI did more than influence the direction of research in the U.S. It catalyzed a worldwide effort and spurred an explosion of creativity in the scientific community. And we’re reaping the rewards not just in medicine, but also clean energy, environmental remediation, and beyond.

Before the NNI, there were people who thought nanotechnology was a gimmick. I began my research career in chemistry, but it seemed to me that nanotechnology was a once-in-a-lifetime opportunity: the opening of a new field that crossed scientific disciplines. In the wake of the NNI, my university, Northwestern University, made the strategic decision to establish the International Institute for Nanotechnology, which now represents more than $1 billion in pure nanotechnology research, educational programs, and supporting infrastructure. Other universities across the U.S. made similar investments, creating new institutes and interdisciplinary partnerships.

Moreover, as a new route to inter- or transdisciplinary research, which was at the core of the NNI, nanotechnology has driven a new narrative in STEM: collaboration. Nanotechnology has captured the imagination of a generation of materials scientists, chemists, physicists, and biologists to synthesize and understand new materials; as well as inspiring engineers who are trained to develop tools for making and manipulating such structures; and doctors who can use them in the clinic. Collaborative nanotechnology research at our institute unites faculty members from 32 departments across four schools at Northwestern. This diversity of training and perspective does more than broadening the scope of our research. It enables us to identify, understand and address big problems—and it helps us break down barriers between the lab and the marketplace.

A Big Bet on Nanotechnology Has Paid Off, Chad Mirkin is director of the International Institute for Nanotechnology, George B. Rathmann Professor of Chemistry and a professor of materials science and engineering, medicine, biomedical engineering, and chemical and biological engineering at Northwestern University.

Topics: Economics, Futurism, Magnetism, Transportation

In the desert just north of Las Vegas, a long white metal tube sits at the base of the mountains, promising to one day revolutionize travel.

That is where Virgin Hyperloop, whose partners include Richard Branson's Virgin Group, is developing the technology for passenger pods that will hurtle at speeds of up to 750 miles an hour (1,200 kph) through almost air-free vacuum tunnels using magnetic levitation.

"It will feel like an aircraft at take-off and once you're at speed," said co-founder and Chief Executive Josh Giegel, who gave Reuters an exclusive tour of the pod used in its November test run, where it was propelled along a 500 meter (1,640 ft.) tunnel.

"You won't even have turbulence because our system is basically completely able to react to all that turbulence. Think noise-canceling but bump-canceling, if you will."

Virgin Hyperloop shows off the future: mass transport in floating magnetic pods, Reuters

Image source: Link below ("ride the lightning")

Topics: Aerodynamics, Futurism, Plasma, Propulsion, Spaceflight

Personal note: I've been offline prepping for my preliminary exam presentation, and grieving the loss of a friend I had known for 40 years since our freshman year at NC A&T. I was his best man. He did not die of COVID, but a heart attack. As such, my remarks were read at the funeral in Indiana, as the pandemic and social distancing concerns did not allow me to give my eulogy in-person. I hope you will forgive my absence.

This past autumn, a professor at Wuhan University named Jau Tang was hard at work piecing together a thruster prototype that, at first, sounds too good to be true.

The basic idea, he said in an interview, is that his device turns electricity directly into thrust — no fossil fuels required — by using microwaves to energize compressed air into a plasma state and shooting it out like a jet. Tang suggested, without a hint of self-aggrandizement, that it could likely be scaled up enough to fly large commercial passenger planes. Eventually, he says, it might even power spaceships.

Needless to say, these are grandiose claims. A thruster that doesn’t require tanks of fuel sounds suspiciously like science fiction — like the jets on Iron Man’s suit in the Marvel movies, for instance, or the thrusters that allow Doc Brown’s DeLorean to fly in “Back to the Future.”

But in Tang’s telling, his invention — let’s just call it a Tang Jet, which he worked on with Wuhan University collaborators Dan Ye and Jun Li — could have civilization-shifting potential here in the non-fictional world.

This Scientist Says He’s Built a Jet Engine That Turns Electricity Directly Into Thrust, Dan Robitzski, Futurism

Quantum physics experiment has demonstrated an important step toward achieving quantum cryptography among many users, an essential requirement for a secure quantum Internet. Credit: ÖAW and Klaus Pichler Getty Images

Ruha Benjamin was the featured speaker on the DoSER webinar “Race to the Future? Values and Vision in the Design of Technology and Society.” | courtesy Ruha Benjamin

Topics: African Americans, African Studies, Futurism, Sociology

Technology is not unbiased, according to a scholar investigating the phenomenon of technological racism. As people recognize the embedded biases within technology, the growing and multifaceted tech justice movement is working to counter these biases, added the scholar.

Ruha Benjamin, a sociologist, and professor of African American studies at Princeton University whose work explores the social dimensions of science, technology, and medicine, spoke during the “Race to the Future? Values and Vision in the Design of Technology and Society” webinar hosted on Aug. 13 by the AAAS Dialogue on Science, Ethics and Religion program. DoSER facilitates dialogue between scientific and religious communities by hosting symposia and lectures on topics at the interface of science, ethics, and religion; training and supporting scientists on engagement with faith communities; and helping seminaries integrate science into their core curricula.

Webinar viewers were invited to consider which prejudices and values are incorporated into technologies such as search engines and AI algorithms and to identify methods to dismantle technological racism.

Technology is often spoken about as if it were a force separate from human influence, Benjamin said. Yet “human beings are behind the screen: our values, our ideologies, our biases, and assumptions.”

Benjamin also pointed out that the biases extend beyond individuals to the systems as a whole and the historical data inputted into the machines. Much in the way that racism exists in legal, educational, and health systems, it also becomes codified in computer systems, she said. For instance, searching for images of “professional hairstyles” and “unprofessional hairstyles” on Google brings up results that equate naturally Black hair with a lack of professionalism – search results that echo real-life biases, she said.

Technology’s Built-In Machine Bias Reflects Racism, Scholar Says, Andrea Korte, AAAS

Topics: Biology, Entropy, Existentialism, Futurism

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1. Humans are driving one million species to extinction, Jeff Tollefson, Nature
2. Unless It Changes, Capitalism Will Starve Humanity By 2050, Drew Hansen, Forbes