The ability to detect with high accuracy if someone is lying would be extremely useful in many scenarios, but most obviously law enforcement. The idea is so alluring that we collectively just cannot give up on it, no matter how elusive the technology has turned out to be. The media typically presents the issue as a matter of lie-detection technology, and likes to hype new fancier technology as if that is going to be the path toward highly effective lie detection. I will explain below why that is likely not true, but first lets take a look at the latest such reporting.

A recent BBC article, True story? Lie detection systems go high-tech, is typical. They highlight a study from researchers at Tel Aviv published in December 2021 that uses electromyography to measure facial muscle movements as a telltale sign of lying. The BBC’s summary of this study is essentially that the researchers found there are two types of liars, those that move their mouth when they lie and those that move their eyebrows. Further, the research found that lie detection based on this method is “73% accurate”.

There are multiple methods for machine-enhanced lie detection. The classic lie detector is based on measuring physiological parameters, like heart rate, breathing and sweating. These are essentially measures of anxiety, and so this type of lie detector is really an anxiety detector, based on the assumption that people who are lying are more likely to be anxious than someone telling the truth. However, there are good liars who do not get anxious, and there are people who get anxious because they are being grilled, whether or not they are guilty of something. So these type of lie detectors have a high false positive and false negative rate.

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The Twitterverse is outraged, appropriately, it turns out, that Florida Acting Surgeon General Joseph Ladapo, who is undergoing confirmation hearings, refused to state when asked directly four times, that the COVID vaccines are safe and effective. At first he straight-up dodged the question, saying, “The question is a scientific one.” Uh, yeah, and you’re an MD, PhD with a degree in public health (i.e. a medical scientist) so answer the question. When pushed repeatedly he finally did answer that the vaccines have:

“reasonable effectiveness for the prevention of hospitalization and death” and “relatively low effectiveness for prevention” against transmission over time.

This is not accurate. They have extremely high effectiveness at preventing hospitalization and death. The risk of dying from COVID is 53 times greater for those who are unvaccinated vs those who are fully boosted.  Regarding prevention of transmission, Ladapo is narrowly correct but misleading through selective reporting. Studies show that a fully vaccinated person has a relative risk of 0.32 of passing on the virus compared to an unvaccinated person (so an unvaccinated person who gets COVID is 3 times more likely to pass it on). This is not “low effectiveness”, but the same data does also show that this protection wanes over time, and is mostly gone three months after the second shot. However, this is for vaccinated but not boosted individuals. Other studies show that boosted individuals have a 93% relative reduction in their risk of contracting COVID (even Delta), either symptomatic or asymptomatic, and of course people who never catch the virus cannot pass it on.

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In “The Future” we will have flying cars. Or so we have been promised since there were cars. The flying car is an almost ubiquitous element of visions of the future, whenever that future is. I have been seeing prototype flying cars on TV since I was a child, with reporters breathlessly touting how soon we might have one in every garage. And yet this promise remains elusive.

Here is yet another report of yet another flying car – as the BBC reports:

A flying car capable of hitting speeds over 100mph (160kmh) and altitudes above 8,000ft (2,500m) has been issued with a certificate of airworthiness by the Slovak Transport Authority.

The AirCar has been extensively tested and completed short a 35-minute flight between international airports in Nitra and Bratislava, Slovakia. The company reports is should have a range of about 1,000 km, and it runs on regular gasoline. The wings fold entirely back so that it can drive on regular roads, and takes two minutes 15 seconds to change from car to plane. But then, of course, you need a runway to take off.

So yeah, it’s a flying car, or at least one type of one, a hybrid vehicle that can convert from a car to a plane. It is then flown exactly like a plane, requiring a runway to take off and a pilot’s license to fly. It’s also not the first one. However, I don’t consider this to be the “flying car” we were promised. A fully realized flying car needs vertical take-off and landing so that it can travel point-to-point, without the need for an airport. The AirCar is more of a regular plane that can convert into a car. This makes it feel like a bait-and-switch.

But past futurism aside – is the AirCar a novelty or potentially something useful? Avionics expert Dr. Steve Wright nailed it, I think, when he said:

Was there ever or is there currently any life on Mars is one of the biggest scientific questions of our time. If we do manage to find the remnants of life on Mars, we may be able to ask a deeper question – what is the relationship between that life and life on Earth? Are they related or completely independent? This, in turn, informs our speculations about how common life is in the Universe. For how, however, the question about life on Mars in an open one.

There are essentially three lines of evidence we can potentially bring to bear to help answer this question. The first, of  course, would be the direct detection of extant life on Mars. If little critters are still metabolizing in the soil of Mars we could detect the products of their metabolism, and perhaps even detect the critters themselves. The second method is to detect the conditions for life, either at present or in ancient Mars. It now seems likely, for example, that ancient Mars had liquid water on its surface, which is a very compatible environment for life.

The final method is to detect fossil evidence of life on Mars. This does not have to be literal “fossils” as most people think of the term, meaning petrified bones, but rather some signature of life in the Martian environment. One of the missions of the Perseverence rover on Mars is to look for these signatures, and to prepare samples for possible return to Earth. But don’t forget about the Curiosity rover, which is still roving around Mars. Recently Curiosity concluded an analysis of Martian rock which produced some very – curious – results, that could be a possible signature of past life on Mars (“possible” being the operative word there).

The experiment involved heating 24 different powdered rock samples (some from rock beds known to be ancient) to release gases, then measuring the ratio of C13 to C12 released, and finding a depleted C13 ratio, which could be an indication of life. Some background is needed here. Isotopes are different kinds of an element with different numbers of neutrons. Elements are determined by their number of positively-charged protons, with carbon having six protons. Neutrons have no charge but do affect the total mass of the atoms. The most common isotope of carbon is C12, with six protons and six neutrons. The second most common isotope is C13, with seven neutrons. Both of these isotopes are stable, meaning they do not decay over time.

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Arguably the biggest question is cosmology is where the Big Bang came from. We can extrapolate back from our observations of the universe and draw some high confidence conclusions. Since the universe is expanding, if we rewind time then the universe would contract as we go back in time until – it must have been a single point, an original singularity. The moment this point expanded rapidly into the universe was the Big Bang, but where did all the matter and energy that make up the universe come from to begin with? To make matters more confusing, the Big Bang also created space-time, so any reference to things happening at or before the Big Bang is tricky.

We can actually do experiments to test our ideas about the very early universe (less than a second after the Big Bang) by reproducing these high energies in particle accelerators. But at some point the energies exceed anything we can produce, and we are in the realm of purely theoretical physics. The question of where the singularity that became the Big Bang came from fits into this category.

There is no shortage of hypotheses about where the universe came from. One question is whether or not the universe could have come from literally nothing. This is a deep question that would take a book-length discussion to explore fully. My very basic understanding is that there are essentially two camps. The first states that something cannot come from nothing, and therefore there always had to be something, even if it was only a quantum fluctuation similar to what exists in “empty” space within our universe. Even the emptiest of space still contains a quantum “foam” of energy with particles briefly coming into existence and then annihilating each other. Maybe the entire universe is a giant quantum fluctuation in some grander quantum foam.

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There have been five recognized mass extinctions in the history of life on Earth, and a number of smaller ones. They include, in order:

• Ordovician (444 million years ago; mya) – climate change caused by continental drift
• Devonian (360 mya) – volcanic eruptions
• Permian (250 mya) – unknown, could be asteroid strike, eruptions, climate change
• Triassic-Jurassic (200 mya) – volcanic activity
• KT (65 mya) – asteroid strike

Many scientists believe we are now in the middle of a sixth mass extinction, this time cause entirely by anthropogenic factors – human activity. We are warming the atmosphere and oceans, acidifying the oceans, polluting the environment, overfishing, hunting some species to extinction, converting ecosystems to farmland and living space, and spreading invasive species. The evidence of a slow-rolling mass extinction seems to be obvious, but still there are those who question if it is really happening. That questioning ranges from healthy scientific skepticism to outright denial.

The reason for the debate is our ability to rigorously document the extinction rate over time. It’s not enough to point out that extinctions are happening. The current estimate is that there are 8.7 million species of plants and animals extant today. Extinction is also a natural part of the evolution of life over time, and biologists also estimate that the background extinction rate is about 10% every million years. This can also be expressed as one extinction per million species years (one extinction per million species per year). This means the background rate should be about 870 extinctions per century. Over the last century there have been recorded about 500 animal extinctions. This is the basis for the argument that we are not in the middle of a mass extinction.

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The first day of my high school astronomy class the teacher began with a task – draw the universe. It was a clever way to engage the class, and immediately brought home that none of us had any idea what the universe, as a whole, looked like. Part of our ignorance was due to the fact that scientists didn’t know much about the structure of the universe at the time (1981). This was before we knew about dark matter or dark energy, knew that the universe’s expansion was accelerating, or had many of the modern instruments we now have to survey the universe and build a model. Most of us just drew a bunch of galaxies, but had no idea about the highest level order of structure.

In the forty years since astronomers have been refining our map of the universe. Recently an international team of scientists have built the largest 3D model of the universe to date, using the Dark Energy Spectroscopic Instrument (DESI). We have peered at the universe not only in visible light, but in infrared, ultraviolet, X-rays, and radio waves. We have also discovered new techniques such as gravitational wave astronomy and neutrino detectors, and a host of new phenomena such as fast radio bursts. Just the idea of mapping the dark energy of the universe was not conceived of back then.

So, if I (or more to the point, a team of expert astronomers) were asked to draw the universe, what would that look like? First we need to consider the fact that the question itself needs some clarification. The picture of the universe would look different in the various electromagnetic spectra. A radio map of the universe looks very different from an infrared map of the universe. We often assume we mean a visible light map, but that is not necessarily the case. Also – what are we mapping, baryonic matter, dark matter, dark energy, or all three? Further, the universe is four dimensional, and how are we going to represent this? Yes, I meant four dimensional, it has three spacial and one temporal dimension (that we know of). When we look out into the universe, we are also looking back in time. We can’t ever see the entire universe at once, as it is “now”. In fact “now” is a tricky concept when dealing with such scales. And finally we can only see (by definition) the visible universe, but we know there is much more we can’t see (because it is beyond the envelope of the speed of light – we can’t see past the beginning of the universe).

What I am really interested in is a mental map of the universe, so we don’t have to worry about how we are going to represent it. Let’s just build our mental map.

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David Bennett, 57, had terminal heart disease. He was bed-ridden and kept alive on a heart machine for the last six weeks, a temporary measure at best. He was deemed too sick for a donor heart transplant, which are in limited supply and given to the patients most likely to benefit from them. Essentially, his options were over and death was imminent and unavoidable. For this reason he was considered a viable candidate for an experimental procedure, and the FDA granted emergency use authorization under its compassionate use guidelines.

On January 7th he received a heart transplant from a pig that had been genetically modified to minimize rejection. This is a true milestone – the first successful transplant of a living organ from a non-human donor into a living human (organ xenotransplantation). The reason for the caveats are the fact that pig valves are routinely transplanted into people, but these valves are fixed and therefore not living tissue. Also, you may remember the girl with the baboon heart, Baby Fae, an infant who received a baboon heart in 1984. She lived for 21 days, but this was not considered a viable procedure, which is why it was not repeated. Also, last year a genetically modified pig kidney was transplanted into a human, but they were brain dead at the time.

It remains to be seen how long David Bennett with survive with his new pig heart. Rejection is still a major issue, and he will need to be on powerful immunosuppressant drugs. There is also a reason he was not considered a good candidate for a human heart transplant. But even if the procedure is moderately successful this would represent a true milestone, our entry into the age of routine organ xenotransplantation with genetically modified organs.

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Perhaps the greatest challenge of current theoretical physics is to come up with a testable theory that unites the principles of general relativity with quantum mechanics. This has proven to be a very challenging problem, one that may take generations of physicists to crack. Right now physicists are mostly stuck in the theoretical realm, trying to come up with theories (like string theory) that may be internally mathematically consistent, but are challenging to falsify experimentally. However, Rana Adhikari, professor of physics at Caltech, and her colleagues are trying to come up with a way to do just that. Their approach derives from another weird concept within theoretical physics – that the universe may be pixelated, and may even be a hologram (three dimensions projected from a two dimensional surface).

For background, prior to the 19th century we comfortably lived in what we now call a classical universe. Our models of how the universe works were based upon our observations and experiments within the frame of macroscopic creatures living on the surface of a planet. Galileo and Newton developed, for example, laws of motion that defined how objects move and behave, including Newton’s theory of gravity. However, classical physics started to break down in the 19th century. For example, astronomers making more and more precise measurements of the orbits of the planets were finding that the orbit of Mercury was different than what our classical equations predicted. Those equations work extremely well, but there was something off about Mercury. Attempts at finding an explanation, such as a hidden planet on the other side of the sun, failed. Eventually we had to conclude that our classical equations were not quite right, or at least could not account for the special case of Mercury.

This is where Einstein comes in. First he proposed in theory of special relativity, which fixed some vexing problems in physics by proposing that the speed of light is an absolute constant regardless of frame of reference, and that it was space and time that are variables which can change based upon frame, specifically with respect to relative velocity. This was considered “special” relativity because it only referred to the speed of light. Einstein would have to work for years more before he was able to account for gravity in a theory of general relativity. His new equations not only solved the problem of Mercury’s orbit (it is close enough to the sun that relativistic effects from the sun’s gravity are measurable) but also made a large number of predictions. Over the last century Einstein’s theories have been confirmed to an extremely high degree.

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The Fermi Paradox points to an apparent contradiction – the universe is a big place, and the laws of physics that have allowed life to evolve on Earth are the same everywhere. Therefore, the universe must be humming with life. Yet, we have not detected any evidence of extrasolar life so far. Given our current technology the only way we could have made such a detection is if such life came visiting to our own solar system. To date there is no convincing evidence of aliens visiting the Earth. (This is obviously a much deeper issue, but I strongly stand by this conclusion and firmly reject the arguments of the so-called UFO crowd.) So where is everyone?

There are many possible solutions to the Fermi Paradox, ways of resolving the apparent contradiction, and many of them have merit. But I think a sufficient explanation is simply that interstellar travel is really hard. It is overwhelmingly likely that the vast majority of science fiction, which depicts some form of faster-than-light (FTL) travel, is wrong. FTL ships are a necessary plot device to have a story span multiple worlds, but the reality is quite different.

At present there is no plausible or even theoretical method for FTL travel. Worm holes almost certainly won’t work. There is no hyperspace or subspace, no warp drive, or jump ships. At this point it seems overwhelmingly likely that the laws of physics simply do not allow for FTL travel. Einstein will not be denied. Of course, we don’t know what we don’t know, and there may be some subtle aspects to the universe we are missing that will allow for FTL travel. But it doesn’t seem likely. And if it is theoretically possible, it is also highly likely that incredibly advanced technologies harnessing massive amounts (prohibitive amounts) of energy would be required.

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