Mar 01 2024

Virtual Walking

When I use my virtual reality gear I do practical zero virtual walking – meaning that I don’t have my avatar walk while I am not walking. I general play standing up which means I can move around the space in my office mapped by my VR software – so I am physically walking to move in the game. If I need to move beyond the limits of my physical space, I teleport – point to where I want to go and instantly move there. The reason for this is that virtual walking creates severe motion sickness for me, especially if there is even the slightest up and down movement.

But researchers are working on ways to make virtual walking a more compelling, realistic, and less nausea-inducing experience. A team from the Toyohashi University of Technology and the University of Tokyo studied virtual walking and introduced two new variables – they added a shadow to the avatar, and they added vibration sensation to the feet. An avatar is a virtual representation of the user in the virtual space. Most applications allow some level of user control over how the avatar is viewed, but typically either first person (you are looking through the avatar’s eyes) or third person (typically your perspective is floating above and behind the avatar). In this study they used only first person perspective, which makes sense since they were trying to see how realistic an experience they can create.

The shadow was always placed in front of the avatar and moved with the avatar. This may seem like a little thing, but it provides visual feedback connecting the desired movements of the user with the movements of the avatar. As weird as this sounds, this is often all that it takes to not only feel as if the user controls the avatar but is embodied within the avatar. (More on this below.) Also they added four pads to the bottom of the feet, two on each foot, on the toe-pad and the heel. These vibrated in coordination with the virtual avatar’s foot strikes. How did these two types of sensory feedback affect user perception?

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Feb 27 2024

Frozen Embryos Are Not People

Amid much controversy, the Alabama State Supreme Court ruled that frozen embryos are children. They did not support their decision with compelling logic, with cited precedence (their decision is literally unprecedented), with practical considerations, or with sound ethical judgement. They essentially referenced god. It was a pretty naked religious justification.

The relevant politics have been hashed out by many others. What I want to weigh in on is the relevant logic. Two years ago I wrote about the question of when a fetus becomes a person. I laid out the core question here – when does a clump of cells become a person? Standard rhetoric in the anti-abortion community is to frame the question differently, claiming that from the point of fertilization we have human life. But from a legal, moral, and ethical perspective, that is not the relevant question. My colon is human life, but it’s not a person. Similarly, a frozen clump of cells is not a child.

This point inevitably leads to the rejoinder that those cells have the potential to become a person. But the potential to become a thing is not the same same as being a thing. If allowed to develop those cells have the potential to become a person – but they are not a person. This would be analogous to pointing to a stand of trees and claiming it is a house. Well, the wood in those trees has the potential to become a house. It has to go through a process, and at some point you have a house.

That analogy, however, breaks down when you consider that the trees will not become a house on their own. An implanted embryo will become a child (if all goes well) unless you do something to stop it. True but irrelevant to the point. The embryo is still not a person. The fact that the process to become a person is an internal rather than external one does not matter. Also, the Alabama Supreme Court is extending the usual argument beyond this point – those frozen embryos will not become children on their own either. They would need to go through a deliberate, external, artificial process in order to have the full potential to develop into a person. In fact, they would not exist without such a process.

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Feb 23 2024

Odysseus Lands on the Moon

December 11, 1972, Apollo 17 soft landed on the lunar surface, carrying astronauts Gene Cernan and Harrison Schmitt. This was the last time anything American soft landed on the moon, over 50 years ago. It seems amazing that it’s been that long. On February 22, 2024, the Odysseus soft landed on the Moon near the south pole. This was the first time a private company has achieved this goal, and the first time an American craft has landed on the Moon since Apollo 17.

Only five countries have ever achieved a soft landing on the moon, America, China, Russia, Japan, and India. Only America did so with a crewed mission, the rest were robotic. Even though this feat was first accomplished in 1966 by the Soviet Union, it is still an extremely difficult thing to pull off. Getting to the Moon requires powerful rocket. Inserting into lunar orbit requires a great deal of control, on a craft that is too far away for real time remote control. This means you either need pilots on the craft, or the craft is able to carry out a pre-programmed sequence to accomplish this goal. Then landing on the lunar surface is tricky. There is no atmosphere to slow the craft down, but also no atmosphere to get in the way. As the ship descends it burns fuel, which constantly changes the weight of the vehicle. It has to remain upright with respect to the lunar surface and reduce its speed by just the right amount to touch down softly – either with a human pilot or all by itself.

The Odysseus mission is funded by NASA as part of their program to develop private industry to send instruments and supplies to the Moon. It is the goal of their Artemis mission to establish a permanent base on the moon, which will need to be supported by regular supply runs. In January another company with a NASA grant under the same program, Astrobotic Technology, sent their own craft to the Moon, the Peregrine. However, a fuel leak prevented the craft from orienting its solar panels toward the sun, and the mission had to be abandoned. This left the door open for the Odysseus mission to grab the achievement of being the first private company to do so.

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Feb 22 2024

AI Video

Recently OpenAI launched a website showcasing their latest AI application, Sora. This app, based on prompts similar to what you would use for ChatGPT or the image creation applications, like Midjourney or Dalle-2, creates a one minute photorealistic video without sound. Take a look at the videos and then come back.

Pretty amazing. Of course, I have no idea how cherry picked these videos are. Were there hundreds of failures for each one we are seeing? Probably not, but we don’t know. They do give the prompts they used, and they state explicitly that these videos were created entirely by Sora from the prompt without any further editing.

I have been using Midjourney quite extensively since it came out, and more recently I have been using ChatGPT 4 which is linked to Dalle-2, so that ChatGPT will create the prompt for you from more natural language instructions. It’s pretty neat. I sometimes use it to create the images I attach to my blog posts. If I need, for example, a generic picture of a lion I can just make one, rather than borrowing one from the internet and risking that some German firm will start harassing me about copyright violation and try to shake me down for a few hundred Euros. I also make images for personal use, mostly gaming. It’s a lot of fun.

Now I am looking forward to getting my hands on Sora. They say that they are testing the app, having given it to some creators to give them feedback. They are also exploring ways in which the app can be exploited for evil and trying to make it safe. This is where the app raises some tricky questions.

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Feb 20 2024

Scammers on the Rise

Good rule of thumb – assume it’s a scam. Anyone who contacts you, or any unusual encounter, assume it’s a scam and you will probably be right. Recently I was called on my cell phone by someone claiming to be from Venmo. They asked me to confirm if I had just made two fund transfers from my Venmo account, both in the several hundred dollar range. I had not. OK, they said, these were suspicious withdrawals and if I did not make them then someone has hacked my account. They then transferred me to someone from the bank that my Venmo account is linked to.

I instantly knew this was a scam for several reasons, but even just the overall tone and feel of the exchange had my spidey senses tingling. The person was just a bit too helpful and friendly. They reassured me multiple times that they will not ask for any personal identifying information. And there was the constant and building pressure that I needed to act immediately to secure my account, but not to worry, they would walk me through what I needed to do. I played along, to learn what the scam was. At what point was the sting coming?

Meanwhile, I went directly to my bank account on a separate device and could see there were no such withdrawals. When I pointed this out they said that was because the transactions were still pending (but I could stop them if I acted fast). Of course, my account would show pending transactions. When I pointed this out I got a complicated answer that didn’t quite make sense. They gave me a report number that would identify this event, and I could use that number when they transferred me to someone allegedly from my bank to get further details. Again, I was reassured that they would not ask me for any identifying information. It all sounded very official. The bank person confirmed (even though it still did not appear on my account) that there was an attempt to withdraw funds and sent me back to the Venmo person who would walk be through the remedy.

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Feb 19 2024

Fake Fossils

Published by under Evolution
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In 1931 a fossil lizard was recovered from the Italian Alps, believed to be a 280 million year old specimen. The fossil was also rare in that it appeared to have some preserved soft tissue. It was given the species designation Tridentinosaurus antiquus and was thought to be part of the Protorosauria group.

A recent detailed analysis of the specimen, hoping to learn more about the soft tissue elements of the fossil, revealed something unexpected. The fossil is a fake (at least mostly). What appears to have happened is that a real fossil which was poorly preserved was “enhanced” to make it more valuable. There are real fossilized femur bones and some bony scales on what was the back of the lizard. But the overall specimen was poorly preserved and of not much value. What the forger did was carve out the outline of the lizard around the preserved bones and then paint it black to make it stand out, giving the appearance of carbonized soft tissue.

How did such a fake go undetected for 93 years? Many factors contributed to this delay. First, there were real bones in the specimen and it was taken from an actual fossil deposit. Initial evaluation did reveal some kind of lacquer on the specimen, but this was common practice at the time as a way of preserving the fossils, so did not raise any red flags. Also, characterization of the nature of the black material required UV photography and microscopic examination using technology not available at the time. This doesn’t mean they couldn’t have revealed it as a fake back then, but it is certainly much easier now.

It also helps to understand how fossils are typically handled. Fossils are treated as rare and precious items. They are typically examined with non-destructive techniques. It is also common for casts to be made and photographs taken, with the original fossils then catalogued and stored away for safety. Not every fossil has a detailed examination before being put away in a museum drawer. There simply aren’t the resources for that.

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Feb 16 2024

Biofrequency Gadgets are a Total Scam

I was recently asked what I thought about the Solex AO Scan. The website for the product includes this claim:

AO Scan Technology by Solex is an elegant, yet simple-to-use frequency technology based on Tesla, Einstein, and other prominent scientists’ discoveries. It uses delicate bio-frequencies and electromagnetic signals to communicate with the body.

The AO Scan Technology contains a library of over 170,000 unique Blueprint Frequencies and created a hand-held technology that allows you to compare your personal frequencies to these Blueprints in order to help you achieve homeostasis, the body’s natural state of balance.

This is all hogwash (to use the technical term). Throwing out the names Tesla and Einstein, right off, is a huge red flag. This is a good rule of thumb – whenever these names (or Galileo) are invoked to hawk a product, it is most likely a scam. I guess you can say that any electrical device is based on the work of any scientist who had anything to do with electromagnetism.

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Feb 15 2024

Using AI and Social Media to Measure Climate Change Denial

A recent study finds that 14.8% of Americans do not believe in global climate change. This number is roughly in line with what recent survey have found, such as this 2024 Yale study which put the figure at 16%. In 2009, by comparison, the figure was at 33% (although this was a peak – the 2008 result was 21%). The numbers are also encouraging when we ask about possible solutions, with 67% of Americans saying that we should prioritize development of green energy and should take steps to become carbon neutral by 2050. The good news is that we now have a solid majority of Americans who accept the consensus on climate change and broadly support measures to reduce our carbon footprint.

But there is another layer to this study I first mentioned – the methods used in deriving the numbers. It was not a survey. It used artificial intelligence to analyze posts on X (Twitter) and their networks. The fact that the results aligns fairly well to more tried and true methods, like surveys, is somewhat validating of the methods. Of course surveys can be variable as well, depending on exactly how questions are asked and how populations are targeted. But multiple well designed survey by experienced institutions, like Pew, can create an accurate picture of public attitudes.

The advantage of analyzing social media is that it can more easily provide vast amounts of data. The authors report:

We used a Deep Learning text recognition model to classify 7.4 million geocoded tweets containing keywords related to climate change. Posted by 1.3 million unique users in the U.S., these tweets were collected between September 2017 and May 2019.

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Feb 13 2024

Flow Batteries – Now With Nanofluids

Battery technology has been advancing nicely over the last few decades, with a fairly predictable incremental increase in energy density, charging time, stability, and lifecycle. We now have lithium-ion batteries with a specific energy of 296 Wh/kg – these are in use in existing Teslas. This translates to BE vehicles with ranges from 250-350 miles per charge, depending on the vehicle. That is more than enough range for most users. Incremental advances continue, and every year we should expect newer Li-ion batteries with slightly better specs, which add up quickly over time. But still, range anxiety is a thing, and batteries with that range are heavy.

What would be nice is a shift to a new battery technology with a leap in performance. There are many battery technologies being developed that promise just that. We actually already have one, shifting from graphite anodes to silicon anodes in the Li-ion battery, with an increase in specific energy to 500 Wh/kg. Amprius is producing these batteries, currently for aviation but with plans to produce them for BEVs within a couple of years. Panasonic, who builds 10% of the world’s EV batteries and contracts with Tesla, is also working on a silocon anode battery and promises to have one in production soon. That is basically a doubling of battery capacity from the average in use today, and puts us on a path to further incremental advances. Silicon anode lithium-ion batteries should triple battery capacity over the next decade, while also making a more stable battery that uses less (or no – they are working on this too) rare earth elements and no cobalt. So even without any new battery breakthroughs, there is a very bright future for battery technology.

But of course, we want more. Battery technology is critical to our green energy future, so while we are tweaking Li-ion technology and getting the most out of that tech, companies are working to develop something to replace (or at least complement) Li-ion batteries. Here is a good overview of the best technologies being developed, which include sodium-ion, lithium-sulphur, lithium-metal, and solid state lithium-air batteries. As an aside, the reason lithium is a common element here is because it is the third-lightest element (after hydrogen and helium) and the first that can be used for this sort of battery chemistry. Sodium is right below lithium on the period table, so it is the next lightest element with similar chemistry.

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Feb 12 2024

The Exoplanet Radius Gap

Published by under Astronomy
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As of this writing, there are 5,573 confirmed exoplanets in 4,146 planetary systems. That is enough exoplanets, planets around stars other than our own sun, that we can do some statistics to describe what’s out there. One curious pattern that has emerged is a relative gap in the radii of exoplanets between 1.5 and 2.0 Earth radii. What is the significance, if any, of this gap?

First we have to consider if this is an artifact of our detection methods. The most common method astronomers use to detect exoplanets is the transit method – carefully observe a star over time precisely measuring its brightness. If a planet moves in front of the star, the brightness will dip, remain low while the planet transits, and then return to its baseline brightness. This produces a classic light curve that astronomers recognize as a planet orbiting that start in the plane of observation from the Earth. The first time such a dip is observed that is a suspected exoplanet, and if the same dip is seen again that confirms it. This also gives us the orbital period. This method is biased toward exoplanets with short periods, because they are easier to confirm. If an exoplanet has a period of 60 years, that would take 60 years to confirm, so we haven’t confirmed a lot of those.

There is also the wobble method. We can observe the path that a star takes through the sky. If that path wobbles in a regular pattern that is likely due to the gravitational tug from a large planet or other dark companion that is orbiting it. This method favors more massive planets closer to their parent star. Sometimes we can also directly observe exoplanets by blocking out their parent star and seeing the tiny bit of reflected light from the planet. This method favors large planets distant from their parent star. There are also a small number of exoplanets discovered through gravitational microlensing, and effect of general relativity.

None of these methods, however, explain the 1.5 to 2.0 radii gap. It’s also likely not a statistical fluke given the number of exoplanets we have discovered. Therefore it may be telling us something about planetary evolution. But there are lots of variables that determine the size of an exoplanet, so it can be difficult to pin down a single explanation.

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