26 July 2023

Google Bard answers about the Age of the Universe

I tried Google Bard, Google's alternative to ChatGPT.

Here's what it said when I asked it if there were good reasons to believe recent reports that the age of the universe is about 27 Ga, much older than previously thought. Here's what it said. Pretty basic, but actually about what I'd have said if I thought about it a bit.

There are some good reasons to believe recent reports that the age of the universe is 27 billion years, much older than previously thought.

One reason is that the James Webb Space Telescope (JWST) has been able to observe galaxies that are much older than what was previously thought possible. The JWST was launched in December 2021, and it has been able to see galaxies that formed just a few hundred million years after the Big Bang. This is much earlier than the previous estimates of the age of the universe, which put it at around 13.8 billion years old.

Another reason to believe that the universe is older than previously thought is that there are some theoretical models that suggest that the expansion of the universe is accelerating. If this is true, then it means that the universe is older than what we would expect if it was expanding at a constant rate.

However, there are also some reasons to be skeptical of the recent reports that the age of the universe is 27 billion years old. One reason is that the models that suggest that the universe is accelerating are not yet fully understood. It is possible that these models are wrong, and that the universe is actually expanding at a constant rate.

Another reason to be skeptical is that the observations of the JWST are still being interpreted. It is possible that the galaxies that the JWST has observed are not as old as they seem. It is also possible that there is some other explanation for the observations that does not require the universe to be older than previously thought.

Overall, there are both good reasons to believe and to be skeptical of the recent reports that the age of the universe is 27 billion years old. More research is needed to confirm or refute these reports.

(ChatGPT probably wouldn't answer this as well, because its database is not kept updated to the present (on purpose), so it doesn't even have this information in its database. It would answer anyway, but its answer would probably be meaningless. )

22 July 2023

Are EVs truly more optimal than legacy internal combustion technology?

I pose only a question here, although I will probably spend a bit of time trying to answer it, from whatever reliable information I can find. 

Which is more optimal, internal combustion motor vehicles or electric vehicles if you take it as a given that to consider the true efficiency of each, you need to take into account not only the onboard vehicle efficiency, but the environmental and financial cost of producing and delivering refined fossil fuel, and the environmental effects and financial cost of operating the vehicles over an arbitrarily equivalent "lifetime" (which may ignore superior longevity of EV systems)(and this would have to include impact on climate, which is not zero EVs)?

I'm pretty sure this exercise will show that EVs are greatly better in all important respects, even if you burden them in your weighing of effect with the cost of building out new charging infrastructure. Since we probably aren't considering the very costly geopolitical actions of governments to ensure access to oil (or rare earth metals for that matter), it seems a little unfair to burden the EV paradigm shift with the economic costs of the disruption to legacy internal combustion industry. Particularly since most technological changes intended to reduce the impact on climate are similarly disruptive, and even the mere continued use of ICE technology has many negative and disruptive effects on civilization. 

What are Toyota and Nissan doing/thinking?

According to Sam Evans, The Electric Viking on YT, both Toyota and Nissan are falsely claiming that they are about to begin production of breakthrough solid state batteries for EVs (which would be great if true). He says the complete and easily detectable lack of prototypes or activities related to such a product are the evidence. 

W t f-ing F? 


20 July 2023

A slightly personalized ramble on the EV phenomenon

We've owned an all electric car for a over three years now, and although it's largely anecdotal, here's my take. (We also own a plug in hybrid). 

The pure battery electric car has one major drawback, which is gradually getting better and will disappear entirely fairly soon, probably within the decade. And that is the inadequacy of the charging network/charging technology. Newer battery technology is or promises to very soon be faster, better, made from non-rare materials, and cheaper. The buildout of the "NAS" (Tesla) charging standard, and conversion to it, at least here in No. America, over the next decade will render "range anxiety" and difficulty of charging EVs on road trips pretty much ancient history. In the near future nearly all EVs will charge up to drive two or three hundred miles at a fast charger in less than 20 minutes. Not quite there yet, but getting there. And just as gas stations started appearing everywhere in the late teens of the 20th century so that by 1925 you could get gas almost anywhere, the same is happening with chargers. Look around the built environment. Tesla superchargers, or other chargers, are appearing in parking lots, shopping malls, etc. The most logical next phase of buildouts will be restaurants, fast food places, existing gas stations, commercial parking lots, and even on street parking. Why not? Electric power is available almost anywhere and the cost of mass production and installation of self-contained charging units is coming down almost exponentially. Soon they will be everywhere, and queues to charge your car will be a thing of the past. 

Apart from that one drawback, EVs are superior in every way. People often don't think of not only how expensive gas is, but what a waste of time. Except on roadtrips, which, after all, is only a relatively minor part of most peoples' driving, EVs charge while you're doing something else. Usually at home or work, or while parking someplace. Admittedly, this is more of a problem for renters who can't install chargers in a garage, but this, too, is undergoing a transformation and in the not too distant future small modular charging units will be built into virtually all residential and commercial parking facilities. The logic is inescapable. But having to put gas in a car is a hassle and a waste of time. Not to mention the well recognized health issues associated with gasoline vapor and the pollution from internal combustion. 

Then there's the cost. Electric power transfer to mobility in an EV is much more efficient, despite the losses from batteries, than burning gasoline. This wasn't always true, but it is now. And the cost is about 1/5 the cost of using gasoline. 

Then there's maintenance. Modern cars don't need as much maintenance, but think about it (assuming you're a driver). You know that "30,000 mile service" that costs hundreds? Ever had to change a timing chain, or a clutch, or get transmission service? Although dealers try to get you into their service bays so they can change your cabin air filter, EVs are far simpler and more reliable than ICE cars. The motors are good for about a million miles. The brakes last longer because much of the braking is regenerative, using the electrical system of the car. There is no transmission, no clutch, no engine oil to change, no fan belts, complicated fuel injection systems... on and on. Electric cars are no longer all that much heavier than other cars, so the tires last about the same length of time. Batteries now last years, and are resistant to significant degradation, as well as being modular and replaceable. The replacement of batteries is about on a par with major engine work always necessary in an ICE car eventually, and are actually cheaper, as they are being designed to be modular and upgradeable as technology improves. As many commercial vehicle users have now realized, electric vehicles are only slightly if at all more expensive to buy initially, and are invariably cheaper to maintain and operate than ICE vehicles. The overall cost per mile in 100,000 miles, which is only a fraction of the life of an EV generally, will be substantially lower, on average, with the added benefit of course of zero emissions. Coupled with the changeover society wide to renewable electricity generation and upgraded electric infrastructure, the benefits to the environment are all positive and represent a huge cost saving, long term. 

An early complaint was ineffective air conditioning and heating, but the introduction of heat pump technology as essentially removed that concern completely.   

OK, car buffs. Like to shift gears and vroom around? Well, get over it. Drive an EV. The instant torque, fantastic acceleration, terrific road hugging capacity, and overall driving experience are all vastly superior. You not only get used to how quiet it is, you come to relish that and miss it when you have to drive some old fireburner. Just try it, I virtually guarantee you'll be convinced. Dirty little secret: the performance divisions of major legacy car makers (like Dodge, in particular), have realized that they simply cannot compete with electric cars. Most electric cars are purely utilitarian, but even they have great performance and pickup. The dedicated performance car EVs are absolute ICE killers. In the 1950s a "muscle car" with a huge guzzling V8 might get zero to sixty in ten or eleven seconds... maybe... under ideal circumstances. In the 60s and later, better engine design and engine management technology (complex, expensive and unreliable) gave better performance. But they just can't compete with zero to sixty in three seconds, which is fairly easily achievable in a purpose built EV. Even the consumer products generally have excellent performance by any standard. 

EV sales worldwide are just beginning the upward trajectory of exponential growth. Automakers who are not already producing viable EV products will be challenged to their foundations, and some, even some pretty big companies with big market shares (already peaked and going down), will likely not survive. The Japanese especially seem to have missed this paradigm shift, almost across the board, and the possibility of economic collapse in Japan, where the auto industry is hugely dominant in the economy, is a real threat. The reverberations of a general collapse of the Japanese economy could be pretty devastating, and the time to think about mitigating that is now. EVs are a huge leap forward, but like many major technology shifts, it has the potential to be hugely disruptive. Governments, especially Japan's, had better sit up and take notice, and start taking actions to assure that something resembling an orderly transition takes place. 

18 July 2023

Biden should use Trump's own negativity against him

A continual theme in Donald Trump's hideous and deranged rally rants is "America is in decline;" "going down rapidly," etc. Biden should seize on this. "Donald Trump wants you to believe our best days are behind us. With him as president, that's a self-fulfilling prophecy, especially since he only talks about himself and his sense of entitlement. Not about you, and what's good for you and our country. But I believe America is a great and resilient nation, and our people are strong and resourceful. Our best days are yet to come, and with your help, we can make great progress towards an even more just and prosperous society!" 

Simple and effective.

Shaky republic at grave risk... for real

I've allowed myself to believe that Americans will not actually elect the maniacal narcissist would-be autocrat again. And, if we had a functioning presidential election system, there would indeed be zero chance. But, given the anti-democratic Electoral College system, whereby the only time a Republican has won the popular vote since 1988 was 2004, when the reverberations of 9/11 were still ringing, the right can take power despite being a minority by a significant margin. By any fair standard, given gerrymandering and the Senate system, the right has never won a national election in the current era, but our system actually could put them in power again despite minority status. Terrifying. We must unite and make sure we win, up and down the ballot, by the largest possible margins!

17 July 2023

RFK Jr, bullshit artist and political landmine

In case you don't already have enough proof that RFK Jr. is a nut job conspiracy theorist and willing would-be spoiler for the insurrectionist candidacy of Donald Trump, please read this.  RFKJr Bullshit

This guy is a total disgrace to whatever legacy of genuine leadership his family might once have been able to lay claim to. I truly hope he crashes and burns completely and early, because there is huge potential for tremendous harm to our country. And given his apparent admiration for, and acceptance of evil lies of, Vladimir Putin, the possibility that his misdirection and exploitation of his name to do our country harm is intentional on his part cannot be ignored. The fact that essentially all his money is from dark right wing sources, like the shadowy money behind the phony "No Labels" cabal, is a clue. 

There was a time when as an environmental activist, I admired him and what he seemed to be trying to do as a legal advocate against corporate pollution. But starting with his irrational anti-vax nonsense and culminating in a totally wacko top to bottom conspiratorialist mindset, he has squandered any good will or claim to be taken seriously by anyone. 

A precept I live by (one of several)

Everyone has some sort of precepts they live by, even if they haven't exactly formulated them in words. I heard one today in a video about music I care about, and I realized that I do, in fact, pretty much live by it. 

«Nulla dies sine Bach.»

No day without Bach. 


Note to Toyota and Stellantis: resisting technological change is a loser

People of my age often grew up in "Ford" or "GM" (or, less often, "Chrysler/MoPar") households, where, usually the dad, was a dedicated customer of one of these, time after time. In the 70s lots of people gave up on the Big 3, buying Japanese or German cars, leading to a good deal of brand loyalty, especially towards Honda and Toyota. The reason? Economics. The cars were better and cheaper to operate. 

Now, decades later, after being bailed out by the government (twice in the case of Chrysler), the Big 3 are really the Big 2, with Chrysler a subsidiary of the European company that's a merger of Peugeot group, Fiat, and Chrysler (which is mainly Ram and Jeep nowadays). And, interestingly, the likely future biggest US automaker, Tesla, draws the largest groups of its customers from former customers of Honda and Toyota, which have entirely missed the boat on the market disruption to EV dominance. Ford and GM are trying mightily to make this conversion, but the Japanese and Stellantis aren't. GM and Ford are trying to hold on to some market share. But what are Toyota and Stellantis (Chrysler+) doing? They are trying the political road, trying to lobby the US govt. to back off its industrial policy to encourage the switch to zero emission vehicles so they can go on making gas cars according to their outdated paradigms. 

This strategy is doomed. If Toyota, Honda, Nissan, Mitsubishi, Subaru, Suzuki (notice a theme?), plus Stellantis and BMW all just give up on EVs and try to use public policy to save themselves, they will fail. Tesla and at least 18 Chinese manufacturers are already at the point where their cars will soon be cheaper than gas cars, and while the buildout of the charging infrastructure is slow and incomplete, it is happening. Batteries are better and better, and cheaper, and use less and less rare materials. People are already abandoning outdated technology for  the simple reason that, very soon, per mile driven, EVs will be substantially cheaper, not to mention far less polluting, than internal combustion. And Toyota, Nissan and Honda's sales have collapsed in China (the world's largest car market) already, and are down now everywhere. Particularly Nissan, which is already experiencing sales falling off a cliff, not just in China, but in the US as well. And Honda and Toyota sales are slack and looking bleak as well. What new cars do you see more and more of? Tesla. In Europe (not here due to tariffs) ... Chinese manufacturers like MG (not British anymore), Volvo (also Chinese). Sales of legacy automakers' gas cars have peaked across the board and are very clearly on the downslope. Everywhere in the world. A totally predictable development. 

Toyota and Stellantis are firmly on the side of the dinosaurs, with the asteroid bearing down. Not to give financial advice, but I wouldn't touch their stock. They're doomed. Radical to say the largest automaker in the world, Toyota, is doomed? I don't actually think so. They've failed to invest seriously in battery technology, failed to develop a single practical EV template, much less electric cars anyone would buy, and are chasing ridiculous technologies like hydrogen powered V8s. (Not fuel cells, actual internal combustion engines powered by hydrogen, for which no infrastructure exists or is planned anywhere in the world). They're spreading outright lies about battery technology and new EV manufacturing methods which have already proven themselves. These legacy companies are almost literally tilting at windmills. Bah bye, Toyota, we knew you when. (When you made economical and practical cars while America's makers were the ones floundering). No longer so. And I'll make an easy prediction: when the dust settles, in a decade or so, the biggest automakers will be Tesla, those legacy makers like Daimler, Volkswagen (maybe), Hyundai group, Ford, and GM, which are maybe late to the party but are at least working on the conversion to an EV future. And the Chinese, probably winnowed down to Geely (Volvo), BYD, and a few others. The laggards and denialists, Stellantis, BMW, and all the Japanese companies, will be scrambling, or, in the case of Stellantis, I'd say probably already bankrupt and gone within ten years. Toyota has huge resources, you say? Yeah, but the two biggest corporate debts in the world, in order, are Toyota and Volkswagen. VW is at least working on the problem. Toyota is fat, but not happy, and is whistling past the graveyard while watching their gas powered empire beginning its inexorable collapse. 

Their strategy of going after regulation and industrial policy cannot work, because while these things are helping to bring about the conversion to EVs, what's really driving it is vastly improved technology. And, sadly, the Japanese in particular, and Stellantis most among the Western makers, are just not doing it well enough or fast enough to emerge as major players when the dust settles. 

We suffer more in imagination than in reality. 
-- Seneca 

16 July 2023

Political and physical geography... not always a match

A small observation. Political divisions sometimes trace actual geographic or geological divisions, such as the St. Lawrence and its lakes forming much of the border between Canada and the US in the area. Or the UK occupying a pretty recognizable island province (plus a chunk of someone else's island province, but leave that alone. But often physical geography is not reflected in political division. Oregon and Washington fairly neatly divide into the coastal provinces, where most of the people live (in Oregon the Willamette Valley seaward of the Cascades and a good part of the coastal range; all of this sits atop the geological terrane called Siletzia, which docked with North America about 50 million years ago. The rest of the state is either very mountainous or arid. Same with Washington, where the Sahalish (Puget Sound) basin and the same Siletzia terrane contains most of the people, while the rest of the state is pretty mountainous, sparsely populated, and arid. New Guinea is divided east/west politically into Papua/West Papua (which Indonesia claims, formerly Irian Jaya) on the western half, and Papua New Guinea in the east, an independent nation since 1975. But the geographical division of the island is into a northern and southern province, with the North the collisional (slab failure) mountains formed by the collision of the Australian plate into the Philippine Plate, and the south the portion of the Australian plate that's still colliding. 

15 July 2023

Abiogenetic origin of life-- Metabolism First?

I am reading a truly interesting book, called Spontaneous Order and the Origin of Life (Steven Bratman), on the biochemistry of the origin of life (for nonscientists, although conceptually it does get a teeny bit hairy here and there). The simplest gist: spontaneous (abiogenetic) chemistry precedes actual life: Metabolism First. I feel that this idea is essentially correct (and I use the word "feel" rather than "think" to denote a partially intuitive response). And here's the interesting part: if this is right, then the chemistry of life actually precedes Darwinian evolution and operates more like a non-equilibrium phase shift. Which, if true, for reasons I could almost explain, in turn means that at its metabolic core, life probably really is more or less inevitable if the conditions for it exist. And, according to most planetary formation theories, it should. Not everywhere, but lots of wheres. 

Parenthetically, the sine qua non "conditions" include the functional equivalent of "white smoker" hydrothermal vents, which were present on Earth within 300-500 mA after the inception, and are likely present on at least some substantial percentage of aqueous lithic planets literally everywhere in the universe. By "substantial" I mean, say more than half a percent or so, since there probably are many, many ways for things to go wrong. I like the term "aqueous lithic" better than "terrestroid" or "earthlike," which are somewhat inaccurate in their implications. Most such planets are likely actually quite unlike Earth, since there seems to be growing evidence that Earth is close to the lower mass threshold for such essential qualities as plate tectonics and moderately deep oceans-- most planets that have these features are probably so-called "Superearths," with masses between 1.0 and 2.0 Earth masses, or so. The larger range of Superearths, which by definition are up to the mass of Neptunelike planets able to hold onto hydrogen in their atmospheres, around 3.0+, are almost certainly uninhabitable for other reasons. 

12 July 2023

Font rant

You read a lot of conflicting information, most of it not evidence based, with precious little reference to actual scientific studies on the subject of which is more readable (or legible, which is more technically defined): serif or sans serif fonts. So the choice has a significant proportion of subjective esthetic judgement involved. 

So, here's my take. Sans serif fonts like Helvetica and Arial arose out of the Bauhaus or Brutalist architectural esthetic of the early to mid 20th century. The dogma that they are "cleaner" and "easier to read" is, in my view, largely false. They were probably adopted for computer screens because, at low resolution, they are easier to reproduce and easier to decipher. But there actually is considerable evidence that not only are serif fonts, when accurately imaged, are at least as easy to read for large amounts of text, and they are generally preferred by readers in such formats as books, journals, and magazines. 

I personally despise the Brutalist esthetic whole cloth, and dislike sans serif fonts for most purposes. Where they are marginally better, I find semi-serif fonts, like Asul or Optima, are even better... such as for screen fonts. But even for e-mail I prefer a nice serif font, like Palatino or (a new favorite) Caladea. Fonts that have genuine italics (which are completely different, not merely algorithmically derived slant).  

I find most people barely notice these differences, but, as someone who had to prepare "camera ready" legal copy for 35 years using ordinary word processing applications, I have strong, and likely unshakeable views on the subject. Down with Arial! Grind it into the dust! Helvetica is only marginally better. It looks and feels anti-human, machinelike, indifferent to emotion, flying in the face of beauty. (By the way, the skinny and really quite ugly Times New Roman is very probably my least favorite serif font). 

I rest my case, and if you are unconvinced I banish you to the virtual realm of the Philistines! You can come out when activities are not textual! 

(G-mail does not offer a full range of fonts. This e-mail should appear in most browsers and e-mail apps in a generic serif font, based on my choices, but many programs substitute fonts willy nilly). 

10 July 2023

Tectonic revolutions and the weirdness of Western North America

About 40 years ago a good friend introduced me to the concept that the Sierra foothills and Coast Range in California were accreted to North America as "island arcs" comparable to Japan, and I found that fascinating, but I admit I pictured Honshu smashing California, one and done. I probably would've been flabbergasted to realize that it wasn't just one island arc, but a whole series of "exotic terranes," and it wasn't just California. All or nearly all of British Columbia, Washington, Oregon, and most of California are made up of exotic slivers and slices, some having moved along faults or caught up in moving plates that originated far away. Some less far. So a big island system, actually probably closer to Kamchatka than Japan, collided and slid along (now North, then mostly east along the now-western, then equatorial and E-W oriented margin of Laurentia (North America). That superterrane, now called Intermontane, consisted of two detached pieces of old North America with a slice of coastal material from Gondwana... now Indonesia... slivered in between. It collided about 170 million years ago. I won't try to account for all of this in a paragraph, but another big one, the Insular superterrane (docked with N. Amer. about 100 million years ago), forms a lot of British Columbia and Alaska. It consisted of Wrangellia, which originated in what is now coastal Siberia (it's controversial) docked way out in the ocean, which was probably the Kula ocean, not the modern Pacific (it's really complicated), with a slice of continental crust, the Alexander Terrane, that made its way along the Uralian ocean then east and north of North America from a point near Europe. A long way, but this was before the modern Atlantic opened up. And that's how the Yellow Aster formation in North Cascades National Park is actually a little piece of the red sandstones that the founder of modern Geology, James Hutton (1726-1797) referred to as the Great Unconformity (coining that word). In Wales. Rocks identical to rocks in Wales are found in the Pacific Northwest, not because they're similar, but because they are the same rocks. So if that doesn't boggle your mind just a bit, you aren't really thinking about it. 

I said this was weird, but actually there are a lot of places in the world that are similarly complex, with bits and pieces rifting, translating, docking... it's extremely complex. There have been at least two, probably three sequences where all the landmasses have come together in a supercontinent, most recently about 400 million years ago as Pangaea. Most people have heard of Pangaea, but the details of how the surface of the Earth has evolved over time are truly amazing, and virtually all of this science has arisen in my lifetime. 

03 July 2023

Lithic worlds, Earths and Super Earths

If the whole subject of speculation about the prevalence of life and the nature of exoplanets makes your eyes glaze over, you may want to skip this musing. 

I have come to what I consider an inescapable conclusion, which I believe will eventually just be one of those "background wisdom" things everyone knows.

Our Solar System (our star system, or SS) has four inner "terrestrial" (terrestroid would be a better word, or perhaps even better, lithic) planets. Some star systems do not have inner lithic planets; some have all or mostly lithic planets, not necessarily close in; and a good fraction of such planets are of the SE type (Super Earth), mass between 1.1 and 2.0 Earth masses, a common enough type that it seems the majority of SSs have at least one. Another type, still lithic but clearly hopeless for life, would be the 2.0 to 3.5 or so range, which are also common and usually lumped in with SE, but actually are clearly different. Beyond 3.5 or so they hold hydrogen and are Neptune-type. No example of a Super Earth exists in our SS. 

But here's my conclusion: 

Our SS has examples of 3 extremely common types, which exemplify, respectively, the large majority of lithic worlds in the universe. Runaway greenhouse, which can happen easily inward of the socalled habitable zone (Venus), but can also happen within and even beyond the habitable zone (colder, farther from star). The second is cold, dry (Mars) type, which can range from Moon size up to a good deal larger than Earth, which is where liquid water did not take hold sufficiently to create an atmosphere that retains water vapor and ozone (a neat, tightly balanced trick). Cold dry worlds (Mars) are probably the most common type of lithic planet, with SEs being second. The third, Mercury, is the hot dry type, which are just too hot, inward of habitable zone, to retain any liquid water or much of an atmosphere at all. Mercury would be Mars type if it were further out. Hot dry worlds are usually tidally locked; a whole other subject which limits habitability even further, but I won't go into that further. If Venus, even though almost Earth size, were where Mercury is, it would look more like Mercury than it does. So this is a separate type, but small lithic bodies quite near stars are also extremely common. 

The gas planets in the SS, apart from being all bunched up and pretty far away, which is not typical but not rare, are nothing special, apart from Satur's especially beautiful rings. 

Which, of course, leaves Earth. Earth is the anomaly, the rarity. And not just because of life. It formed from a major collision, ending up with a large moon and relatively lower density (only slight, but definitely abnormal). It acquired a lot of probably cometary water (not necessarily typical). It is inward of a large gas giant that caused the heavy bombardment period to peter out early. It developed, of course, the unique chemistry of life, quite early on, which came to regulate surface temperature despite the universal tendency of main sequence stars to increase continually in temperature throughout their main sequence lifetimes. And, probably because of life and the advent of free oxygen and thus ozone in the upper atmosphere, it is 1) protected from lethal radiation at the surface and 2) retains water, which otherwise would eventually dissociate at the edge of space into hydrogen and oxygen, and the hydrogen would all escape, converting the Earth into Mars type. This is the usual fate of worlds situated in Earth's approximate position. The presence of oceans for billions of years, therefore, led to plate tectonics, which didn't kick in until about 1 billion years after the origin of the planet, and which is almost certainly necessary to retain habitable conditions on the surface, but which is probably highly unusual in the universe. Quite a number of just barely stable conditions, all of which are necessary for the habitable conditions remaining stable on this planet for more than 3 billion years. 

In other words, Rare Earth. It really is true: a lot of things that can easily stray into the "easy" part of the graph, and cause a planet like Earth to resemble either Venus or  Mars. Only a tiny fraction end up with conditions where life is possible for long periods of time, and of course the regulatory (Gaia-like) nature of biospheres themselves play a big role in that. 

This explains the Fermi Paradox completely, and means that naturally habitable planets are rare as hen's teeth. It is the evolution of intelligent life, however common or rare that turns out to be, that will make life in the wider range common in most of space possible. The natural origin of life really is a near miraculous concatenation of not particularly likely-in-combination factors. 

One countervailing factor: SEs may have all of these characteristics, although probably only at the relatively lower end of mass range. Planets between about 0.9 and 1.5 Earth masses are probably candidates for liquid oceans and plate tectonics. I've seen in print the "educated guess" that the majority of living worlds are probably closer to 1.5, meaning, as living worlds go, Earth may be near the lower end of the mass range. Planets like Mars, or even up to 0.7 or 0.8 Earth masses, probably cannot sustain plate tectonics or retain liquid water over eons, no matter what else may be going on. But it seems likely that most planets that have liquid oceans and plate tectonics are, in fact, SEs. 

The fact that 70%+ of all stars are probably too dim to have a habitable world at all (Class M or red dwarf stars) is another limiting factor, of course, but that's another topic.