Archive for the 'Technology' Category

Dec 07 2018

Real Ion Drives in Mercury Probe

Published by under Technology

Most Star Wars fans know that the name of the iconic TIE fighters is an acronym standing for “Twin ion engines.” Most space fans know that ion engines are real, but are nothing like what we see in the movies.

There is a disappointing disconnect between science fiction and science reality when it comes to space travel. The unfortunate reality is that space travel is really hard, so most science fiction simply makes up super-advanced spaceships with highly unrealistic capabilities. There is artificial gravity, impervious shielding, faster-than-light travel, and seemingly inexhaustible fuel. Only hard science fiction, like the recent show Expanse (which I highly recommend) deals with the reality of even future space travel.

It’s tempting to think that, yeah but this is future or at least very advanced technology, so it’s not unrealistic for that tech. That is the disappointing part – when you realize that, yeah, it is. We won’t be zipping around the galaxy in 200 years. It will still be a challenge to zip around the solar system.

There is some basic physics in the way. First, the human body can only take so much acceleration for so long. To get up to really fast speeds quickly, however, you need acceleration that will challenge human physiology. Optimally, ships will accelerate at a comfortable 1g. This will also solve the lack of gravity thing.

But this gets us to the second problem – maintaining that acceleration requires a massive amount of fuel. There is also something known as the fuel equation, because you need fuel to carry the fuel to carry the fuel, etc. So we have a few options.

Continue Reading »

Like this post? Share it!

No responses yet

Dec 03 2018

Taking A Second Look at Hydrogen

Published by under Technology

There seems to be increasing awareness (and perhaps weakening denial) that we are standing at a critical moment in the history of our civilization. A problem has been looming for decades and we have largely ignored it. Now the effects are starting to be felt, and scientific confidence has only grown stronger over time.

I am talking, of course, about global climate change. There are still significant stragglers, but there is general consensus in the world that we need to urgently decarbonize our civilization. This is definitely one of the greatest challenges that our generation faces, and many suspect the future will judge us largely by how we meet this challenge.

Many groups have rolled up their sleeves, not to just advocate for one or another potential solution, but to chart viable pathways to a zero carbon infrastructure. The bad news is, it won’t be easy and it will cost trillions of dollars. The good news is, we already have the necessary technology and it will save many more trillions of dollars, not to mention disrupted and shortened lives.

A recent article in the Economist goes over the big picture, making a plug for a significant role of hydrogen. They make the good point that we can’t just think about power generation and cars, we have to also think about industry.

Continue Reading »

Like this post? Share it!

No responses yet

Nov 16 2018

Changing the Kilogram

This is one of those items that at first does not seem like a big deal, and probably won’t get much play in the mainstream media, but is actually a significant milestone. Today, the international General Conference on Weights and Measures will meet in Versailles, France, to vote on whether or not to adopt a new standard for the kilogram. This is a formality, because this change has been worked on for years and the standard is now all set to change.

I have been reading a lot recently about the history of science and technology, and one common theme is that an important core feature of our modern society is infrastructure. If, for example, there were some sort of apocalypse, what would it take to reboot society? Theoretically, we would preserve much of our knowledge in books and would not have to start from scratch. The limiting factor would likely be infrastructure. Gasoline engines won out over electric engines for cars partly (and some believe primarily) because the infrastructure for distributing gasoline was put in place before the electrical infrastructure.

Science itself also has an infrastructure, which includes standard weights and measures. This sounds boring, but being able to precisely measure something, using standardized units that every scientist around the world can use, is critically important to both science and technology. Anything that makes doing science easier reduces the cost and increases the pace of science, with incredible downstream benefits.

In 1879 Le Grand K (or the International Prototype Kilogram – IPK) was created – this is a cylinder of platinum and iridium that is the ultimate reference for 1 kilogram. This hunk of metal is kept in a double bell jar, and never touched. Even a slight finger print would change how much it weighs. From this original kilogram, exact copies were made and distributed to countries to serve as their national standard. Occasionally these copies are sent back to France to compare to the original. These copies are then used to calibrate equipment used for precise measurement.

Continue Reading »

Like this post? Share it!

No responses yet

Nov 12 2018

Optimizing Wind Turbines

Published by under Technology

It’s pretty clear at this point that we need to be moving away from fossil fuels as quickly as possible. Fossil fuels essentially are stores of ancient carbon, long sequestered from the environment, that we are now releasing back into the environment, altering the balance of the carbon cycle leading to increased forcing of global temperatures.

The good news is that other forms of energy are advancing nicely. Wind and solar are now past the point of cost effectiveness in many situations – without even counting the cost of pollution, which I think should be counted. If you consider the health and environmental effects of fossil fuel pollution, all other forms of energy become much more cost effective. (This is the idea behind the carbon tax.)

Nuclear, it seems, is likely going to have to be part of any future energy infrastructure that uses minimal fossil fuel, but lags in cost effectiveness. The nuclear industry is responding, however, with safer and cheaper designs.

It is heartening to know that we essentially have the technology to phase out fossil fuel right now, if we had the political will to do so. It is, of course, disheartening that we lack the political will even in the face of a solid scientific consensus, and clear technology options. Further, whatever technology we choose to invest in will only get better over time.

This constant progress has made the conversation about renewable energies in particular interesting – because the facts on the ground are constant evolving. Solar and wind keep getting better and more cost effective. Wind power is particularly interesting because there are so many factors involved – in both the design of the turbines themselves and their placement.

Continue Reading »

Like this post? Share it!

No responses yet

Nov 06 2018

Electron Quantum Metamaterials

Published by under Technology

Material science is, in my opinion, one of the most underappreciated of the sciences. Perhaps because it is so wonky, it doesn’t seem to get much public attention, and yet the development of new materials arguably has the potential to change our civilization more than any other single advance. Our level of technology is largely defined by the materials we have mastered, and discovering a new material is literally a technological game changer.

It’s always hard to predict the next big advance, but there are some intriguing candidates. Interest seems to be clustering around anything on the nano scale – such as carbon nanofibers. Two-dimensional materials that are only one or a few atoms thick (which includes carbon nanofibers) is an area of intense research as well. There is also a relatively new class of materials called metamaterials, which do interesting things with light and other forms of electromagnetic radiation. Metamaterials essentially have emergent properties, and could have potentially exotic applications such as rendering objects invisible in certain frequencies.

A new paper attempts to codify and name one particular type of metamaterial that the authors (Justin C. W. Song & Nathaniel M. Gabor)  are proposing be called “electron quantum metamaterials.”

These types of materials are comprised of two or more layers of two-dimensional nanomaterial that are rotated with respect to each other so that special patterns emerge. This is likened to a moire pattern, where two sets of thin parallel lines are offset from each other by a certain amount and that creates an interference pattern. The interference patterns emerges from the specific relationship between the lines.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 18 2018

Are Robots Taking Our Jobs?

Published by under Technology

If you were a woodworker, or any craftsman or probably had any job, in the 13th century you didn’t have to worry that technological innovation would render your position obsolete. With the industrial revolution, and the technological revolutions since, there has been an increasing pace of turnover of the kinds of jobs needed in the workplace. We no longer need switchboard operators, and the need for carriage drivers has plummeted.

Technology and automation do displace jobs. Worries that robots are coming for our jobs is not new – remember that Twilight Zone episode from 1964 where the W.V. Whipple Manufacturing Co. automates the factory and lets off all the workers? Well here we are more than 50 years later and the unemployment rate is historically low.

There are several ways to measure this, one is the productivity per person, or per hour worked. To put this into perspective, between the year 1 and the year 1820, productivity per year per person increased from about $600 to $1200, essentially doubling in about 2000 years. Since 1820, however, productivity increased to $26,000 – by more than a factor of 20. In the 20th century, the economy has grown by a steady 2% per year. This continuous growth has only been the norm for the past 200 years, however.

The pace of increasing productivity is also increasing. This is largely due to automation, W.V. Whipple style. Machines are increasingly doing much of the repetitive manual labor, and workers using modern technology can simply produce more. It’s often easy to see how automation will displace jobs. Eventually, self-driving cars will displace the Uber drivers who displaced the taxi drivers.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 17 2018

Intense Farming Better Than Organic

Published by under Technology

A new study reviews hundreds of articles on several farming systems (dairy, beef, wheat, and rice) to compare different approaches to farming and their net effect on the environment. They conclude that intensive farming systems are the “least bad” option for providing the food we need. This is in line with previous studies showing that organic farming uses significantly more land than conventional farming.

Farming has a huge negative impact on the environment. There is no way around that basic fact – farmland displaces natural ecosystems and has significant externalities, such as water use, release of CO2 from the soil, and runoff of chemicals into the environment. Right now we are using 11% of all land on Earth for farming, which is most of the land that is reasonably suitable for farming. To meet the needs of a growing population, we may need to expand farmland, into less and less productive land, which would significantly increase the negative impact of farming on the environment.

Some previous studies compared different farming systems by measuring the impact they have on the land. But this type of analysis is misleading – the authors of the current study instead looked at the environmental impact for a given production of food. That is what really matters. They also looked at studies that measured externalities, as listed above. They found:

Their results from four major agricultural sectors suggest that, contrary to many people’s perceptions, more intensive agriculture that uses less land may also produce fewer pollutants, cause less soil loss and consume less water.

They found that organic dairy farming uses twice as much land as conventional farming, for example.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 14 2018

New Apple Watch and Health Screening

Apple recently announced two new health features of their Apple Watch – fall detection and heart monitoring. These are being sold as useful health measures, but there are concerns that this new technology may be more gimmicky than useful, and might actually be counterproductive.

The first feature detects possibly dangerous falls. If the motion detector senses that the wearer has fallen to the ground, and then they don’t move for one minute, the watch will automatically call 911. This superficially sounds reasonable, but the concern is that the tech company has not adequately tested this feature in coordination with medical professionals.

Specifically – what is the sensitivity and specificity of this algorithm? How often will it detect an event that reasonably requires a call to 911, and how many false positives will it generate? How much will this overwhelm emergency services?

What is naive about this feature is the lack of appreciation for the fact that medical interventions need to be evaluated. Why, for example, one minute? That is a round number, but is that really the threshold where the true-positive to false-positive ratio is optimal, while avoiding dangerous delays if someone is really injured?

Also, what will be the net effect of this? Will the drain on resources actually cause more harm than benefit to the users? How will 911 call centers handle these calls? Will they be able to interpret them?

Continue Reading »

Like this post? Share it!

No responses yet

Aug 27 2018

Programmable Matter

Published by under Technology

I have been reading a lot recently about material science and one thing that has struck me is that we still mostly build our civilization out of traditional materials – concrete, steel, wood, ceramics, paper, leather, and plant fibers, for example.  Perhaps the most common modern material is plastic. Look around your home – other than various types of plastic, most of the stuff will be made out of materials we have been using for hundreds or even thousands of years. The notable exception is electronics which often use more recently discovered rare earths.

This is not to say that we don’t have a lot of high-tech new materials, they are just mostly too expensive to find in the average home in abundance, so we sill use a lot of wood, metal, rock, and natural fibers. This is why material scientists are always looking for the next plastic, a truly modern material that is inexpensive, easily manufactured, with properties that make it ideal for many applications.  Perhaps carbon nanofibers (or nanomaterials more broadly) will be that material, and it has tremendous potential, but we’re not there yet.

Scientists report on a new type of material that I don’t think we will be building our homes out of anytime soon, but does potentially open the door to new applications – programmable matter. The material is liquid crystal elastomers (LCEs), which they are able to program into a specific shape using specific wavelengths of light. The material can then oscillate between two different shapes at different temperatures:

To solve this, the researchers installed a light-activated trigger to LCE networks that can set a desired molecular alignment in advance by exposing the object to particular wavelengths of light. The trigger then remains inactive until exposed to the corresponding heat stimuli. For example, a hand-folded origami swan programmed in this fashion will remain folded at room temperature. When heated to 200 degrees Fahrenheit, however, the swan relaxes into a flat sheet. Later, as it cools back to room temperature, it will gradually regain its pre-programmed swan shape.

Continue Reading »

Like this post? Share it!

No responses yet

Aug 23 2018

The Superconductivity Hubbub

A recent paper, published to arXiv, claims to have a method for making a superconducting material at ambient temperatures and pressures. The authors, Dev Kumar Thapa, Anshu Pandey, are from the Indian Institute of Science, and have garnered a lot of attention for their paper. However, recently there was published another paper on arXiv by Brian Skinner from MIT. Skinner noticed a suspicious pattern of repeating noise in two sets of data from the Thapa-Pandey paper. This could be a signature of fabricated data.

Scientific American has a good summary of the whole story, but that’s the quickie version. Skinner did not make any accusations, just published his analysis with a question to the original authors to explain the repeating pattern. Thapa and Pandey have responded only to say their results are being replicated. The rest of the physics community is not satisfied with this response, and are calling for them to send their material to outside labs for completely independent testing.

Another wrinkle to the story is that Pratap Raychaudhuri, a physicist at the Tata Institute of Fundamental Research in India, floated a hypothesis that perhaps the noise is not noise, but a signal resulting from “the natural rotation of particles within a magnetic field.” If that’s the case, then the pattern should replicate. So we are still left with the need to independently replicate the experiments.

The stakes here are high because so-called room temperature superconductivity is one of the holy grails of material science. Superconductivity means that electricity can flow through the medium without resistance, and therefore with no loss of power. A room temperature superconductor could therefore transform electronics, the power grid, and anything using super powerful magnets (like MagLev trains and MRI scans).

The current dominant theory as to how superconductivity works in certain materials two electron can come together to form what’s called a Cooper pair. This pair of electrons can then travel long distances in the material without resistance. However, Cooper pains can only exist at very low temperatures. So the quest has been to find materials that will allow Cooper pairs to exist at higher and higher temperatures.

Continue Reading »

Like this post? Share it!

No responses yet

Next »