Saturday, October 31, 2015

KIC 8462852 And the Likelihood of Finding Alien Civilizations

Over the past few weeks a number of articles have appeared in various news sources about the star KIC 8462852. This was one of the thousands of stars observed by the Kepler telescope in its search for extrasolar planets. For those who are unfamiliar with Kepler and how it works, the telescope observed stars over a long period of time, watching for periodic dips in their brightness that indicated the presence of planets passing in front of the stars and blocking a tiny portion of their light. Kepler’s initial observation period came to an end when two of the reaction wheels used to maintain the stability necessary for precise observations failed, though since then it has been re-purposed for more limited observations. The initial haul of data is still being analyzed and has already resulted in the discovery of hundreds of planets. Some of these planets are super-Earths (planets not much larger than Earth, as opposed to gas giants like Jupiter), and a few are in the theoretical habitable zones around their stars where liquid water could exist on their surfaces, though we as yet have no way of knowing if it actually does.

What stood out about KIC 8462852, a star somewhat larger than the Sun (spectral class F3 as compared to the Sun's G2) that is about 1480 light years away, was that the observed dips in its brightness were too substantial to have been caused by a planet, and they were irregular. In other words, in the two observed dimming events, which came about 750 days apart, the star dimmed, brightened and then dimmed again several times. This is extremely odd, and astronomers have struggled to come up with an explanation that fits the data. This uncertainty led a few astronomers to note that there was an additional possibility that didn’t involve natural phenomena. This was that the star was surrounded by some sort of alien megastructure designed to capture the star’s light for use as an energy source. This sort of construction has been proposed as a theoretical possibility before, with the most complete version being what is known as a Dyson sphere (after Freeman Dyson, who helped popularize the concept), which would totally surround the star in order to capture all or nearly all of its light. This is obviously not what is being observed here, but as Dyson himself later noted that a solid sphere or even ring around a star was "mechanically impossible", so a practical Dyson sphere would have be something like a swarm or bubble of constructs around the star, so the possibility remains open. Furthermore, some have pointed out that the megastructure could be incomplete (whether because it’s still under construction or because it is abandoned and derelict). In any case the idea is that it is something like a "Dyson swarm" that is being seen here.

Most likely, though, the explanation is something far more prosaic. Even the astronomers who have talked about the possibility that what is being seen at KIC 8462852 is an alien artifact have emphasized that the true explanation is likely to be something natural. The leading theories seems to be a unusually large swarm of comets, presumably disturbed by a recent passing star, though some question whether it is possible for a large enough number of comets to account for the data to have been disrupted, or simply dust, though astronomers are not sure why a seemingly older star (KIC 8462852 is thought to be at least as old as the 5-billion-year-old Sun, though there is still some uncertainty about that) would have so much dust around it. Despite the difficulties with both ideas, dust seems to be the most likely cause. Certainly we should want to see a lot more evidence before leaping to the extraordinary conclusion that aliens are the cause, or even anything more than a remote possibility; as Carl Sagan once said, extraordinary claims require extraordinary evidence.

But all the talk about KIC 8462852 does bring up once again the long-running debate over life in the universe, and specifically the likelihood that there are alien civilizations capable of space travel (obviously necessary to build any kind of structures around even the local star) out there somewhere. Of course, there are a lot of uncertainties involved, spelled out most clearly in the famous Drake equation. How many habitable planets are there? How many of those have life? How many planets with life give rise to technological civilizations capable of space travel? How long do such civilizations typically last? Everyone has different answers to these questions, but no one knows for sure. However, I’m willing to give my own take on the matter, even if I can’t claim to be an expert.

From all the planets we have discovered over the past two decades, we can estimate that there are over a hundred billion planets in the Milky Way, which is home to several hundred billion stars, many or even most of which are likely to have planets. Most of these planets will not be at all Earth-like, but it still seems likely that there could be billions in our galaxy that are similar enough to Earth to be considered habitable. The next question is how likely it is that life has arisen on these planets. We’re still not certain exactly how life arose here (though we’re getting closer all the time) and we still haven’t found definitive evidence of life originating anywhere other than Earth. Given how pervasive life is on Earth, though, I would not be surprised if we find traces of it elsewhere in the solar system, such as on Mars, Europa or Enceladus, and the fact that life seems to have appeared fairly early in Earth’s history is also a positive sign for how likely it is to arise in the first place.

But so far we are only talking about life in its most primitive, single-celled form. There is a rather large leap from this to a technological civilization capable of space travel. In fact, even if life in general turns out to be fairly common in the universe, we may find that on the vast majority of planets it consists entirely of single-celled organisms. After all, life existed on Earth for over 3 billion years before multi-cellular life appeared around 600 million years ago. To put that in perspective, life appeared within a billion years of the Earth’s formation and quite soon after the end of the hypothetical Late Heavy Bombardment era, during which it may have been difficult for even primitive life to survive (and even harder for any traces of life that may have arisen to survive for us to find), but for the vast majority of Earth’s history, there were only single-celled organisms – no plants or animals of any sort, much less intelligent life. This may indicate that it takes special conditions that are not easily fulfilled for multicellular life to evolve, and on many planets where life appears, these conditions may never arise.

Even if multicellular organisms appear, there is no guarantee that intelligent life forms will evolve – particularly intelligent life forms capable of constructing spaceships. Multicellular life had been on Earth for over half a billion years before humans evolved, so obviously intelligent life takes some time to appear. Of course on Earth there have been periodic mass extinctions that have wiped out most life, essentially setting back the evolutionary clock, so it isn’t as if we’ve had half a billion years of continuous evolution. On the other hand, other planets are likely to also suffer from periodic mass extinctions, and intelligent life would have to evolve in the periods between such events, which might be difficult if they were more frequent than they are on Earth. And even if intelligent life evolved, it would not necessarily be capable of developing advanced technology. It is often argued that dolphins are highly intelligent, but even if they are as smart as humans, they obviously can’t build spaceships. For that matter, even humans existed for hundreds of thousands of years before developing advanced technology, and we couldn’t have done that without the right raw materials (for instance, sufficient amounts of iron that could be easily mined). Then there is the obvious danger of an advanced civilization destroying itself in a relatively short period of time, just as we could end up destroying ourselves (or at least sending ourselves back to a low level of technology) through nuclear weapons or catastrophic climate change. After all, we've been capable of space travel for only half a century. That's 0.025% of the time modern humans have been around, and 0.000001% of Earth's history. For us to have a chance of encountering (even from a distance) any alien civilizations, some of them would have to last a lot longer than that.

So there probably are a lot of barriers to advanced technological civilizations arising, to the point that they may only appear on a tiny fraction of habitable planets. But on the other hand, if there are 10 billion habitable planets in the galaxy, even a one in a hundred million chance that an advanced civilization had arisen and survived long enough to be around now would mean that there would be a hundred such civilizations. That’s not a particularly huge number, considering how large our galaxy is, and if they are that rare we may have trouble finding them, especially if we keep in mind how huge the distances between stars are - even talking to any aliens living in the KIC 8462852 system would take 3000 years for a single exchange of messages. As for alien civilizations in other galaxies, they would be so far away as to be completely inaccessible even for any form of communication, unless wormholes or other forms of exotic travel turn out to be possible. Still, while it seems too much to hope that KIC 8462852 will turn out to have advanced alien life, it almost certainly does exist somewhere else in the universe, and probably even exists somewhere else in our galaxy. Whether we will ever find it is another matter; however, I am all in favor of continuing to look.

Monday, October 19, 2015

More Election Fun

Having commented recently on the current crop of Republican presidential candidates, it makes sense to talk a little about the Democratic candidates as well, especially since they recently held their first debate. Actually, I made a few observations on them a few months back, and much of that still stands. Furthermore, it is still in my opinion a bit early to be obsessing to much about the US presidential race, as there are still several months until the primaries actually start. However, given the importance of the US president, it is worthwhile to start taking a look at some of the people vying for the position, particularly those who have reasonable positions on the important issues. I’m also going to comment briefly on the Taiwanese presidential race, where there have been some bizarre developments.

If I were to judge the Democratic candidates purely on their current stated positions, Martin O’Malley might have to be my first choice. His policy positions on important issues like climate change, economic inequality, gun control, and reining in Wall Street are as good as or better than those of Hillary Clinton and Bernie Sanders. However, some aspects of his record as mayor of Baltimore and governor of Maryland bother me, and in any case his current prospects are not that great. Sanders is the best prospect for radical, progressive change, which is something I think the United States needs. His positions on the majority of issues are excellent, and as I will discuss further in a moment, he does really seem to be different from your average politician, even on the left. His main weakness is on guns. Though this is perhaps quite as vital an issue as climate change, income inequality, or getting money out of politics, it is still something that is reaching a crisis point in the US, and as I have noted in the past, it is connected with other issues, such as the high numbers of people being shot and killed by the police (to reiterate, though as Black Lives Matter activists correctly state, there is a very clear racial disparity in such incidents, it is also obvious that if guns weren’t so pervasive in the society, police would be much less trigger happy, regardless of the race of the suspects). While Sanders has a far better stance on gun control than anyone on the Republican side, some of his past votes were poor judgment at best. In fact, guns are another of the many issues were there needs to be a radical change in direction, and unlike on other issues, Sanders seems unlikely to provide it. Nevertheless, his excellent views on so many other issues go a long way toward making up for his weakness in this area.

Of course, despite Sanders’ high poll numbers and the huge crowds he has been his drawing, the pundits still consider Hillary Rodham Clinton the favorite to win the Democratic nomination, especially given her strong performance in the debate. Though many progressives have decidedly mixed feelings about Clinton, her stated positions on the majority of issues are solidly progressive, and at least one article I read noted that her voting record as a US Senator was actually slightly more progressive than Barack Obama’s. Perhaps in part due to pressure from popular left-wing Democrats like Sanders and Elizabeth Warren, Clinton’s positions on many issues have moved noticeably further to the left in this campaign. However, she is still overly cautious on many issues, showing a reluctance to push for radical reform. If she is elected and manages to actually carry out everything that she says she want to do, it would certainly make things better in the US, but perhaps not as much as is really needed. Still, if she wins the Democratic nomination, I will support her. Even in the primaries, though I think Sanders and O’Malley have better positions overall, I am not necessarily rooting that strongly for them to beat her. I think she’s a stronger candidate than O’Malley, and her stance on guns is better than that of Sanders. Also, just the fact that if she won she would be the first woman to be US president is a point in her favor.

I should also note that one negative about Clinton in the eyes of most on the left is less of an issue for me, and that is her relatively hawkish stances on foreign policy. I think she may be a little more inclined to rely on military force than is wise, as I definitely think that military force should be an absolute last resort. That said, I don’t think it should be completely ruled out, especially in the face of major humanitarian crises like the war on Syria. I don’t mean that I think US ground troops should be put into Syria or Iraq, or even necessarily that a no fly zone in Syria is a good idea at this point. But if I were US president and I could be convinced, after hearing all the arguments on both sides, that a no fly zone would save civilian lives and was unlikely to make things worse in the long term (such as by exacerbating the already bad relations between the US and Russia or by creating even more chaos in Syria), I would certainly consider it. In other words, while I agree that in most cases US intervention doesn’t help and often even makes bad situations worse, I do think we shouldn’t completely rule anything out if it has the potential to save lives. So while I’m still undecided as to the best course of action in Syria, I tend to think of myself as falling somewhere between Sanders and O’Malley on the one hand and Clinton on the other hand.

But to go back to Sanders, I would like to mention one instance in which he demonstrated how he is different from your average politician. One of the most talked about moments in the debate was when Clinton was once more being grilled on the emails she sent as Secretary of State – the ones that the Republicans, abetted by many in the media, have been trying their best to turn into a scandal – and Sanders stepped in and defended Clinton, saying that people were tired of hearing about “your damn emails” when there were so many important issues facing the country. Not only was this part of Sanders’ narrative about keeping his campaign focused on substantive issues, rather than the meaningless trivial things the media loves to obsess about, it also demonstrated how uninterested he is in point scoring. The average politician would pile on when a rival is on the defensive, but Sanders seems to be genuinely determined to keep the focus on what can be done to solve the problems the US faces. This is definitely very refreshing, as is his call for a political revolution, rather than just incremental reform. Still, at this point I haven’t completely made up my mind between him and Clinton, or for that matter between the two of them and O’Malley.

I have not forgotten that there are other candidates running for the Democratic nomination. But Jim Webb and Lincoln Chafee, aside from having no real chance at winning, are far less progressive than Clinton, the least progressive of the three top candidates, and don’t have anything in particular to recommend them. The most interesting candidate aside from the three discussed above in Lawrence Lessig, who as I have mentioned before I actually met and spoke to once around a decade ago when he was in Taiwan promoting Creative Commons. I agree wholeheartedly with his goal of dramatic campaign reform to get money out of politics, and I wouldn’t mind seeing him getting some traction in the race. He certainly should be allowed to join the next debate, as he probably has at least as much support as Webb and Chaffee, and he is a much better candidate. However, he is still a long shot, and I think it’s unlikely that he has a realistic chance. Finally, there’s Joe Biden, who people keep talking about as a potential candidate. While I like Biden well enough and would almost certainly vote for him if by some chance he won the nomination, he is also less progressive than Clinton (if to the left of Webb and Chafee), and I don’t see any point in him entering the race. If, rather than electing the first woman president of the US, we’re going to elect another white male, at least it should be someone really progressive like Sanders or O’Malley.

But while there are still many months to go before the nominees in the US presidential race will be decided and over a year until the general election, Taiwan’s presidential and legislative elections will take place only three months from now, in mid January, so we’ll have a new Taiwanese president before the Democrats and Republicans have even officially nominated their candidates. But as close as the election is, there’s just been a major change in the race. The ruling KMT (Kuomintang/Guomindang/國民黨) several months ago went through its official process for choosing a candidate by means of a primary. Only one candidate, the right-wing legislator Hung Hsiu-chu, entered the race, so she won by default and was officially nominated by the KMT in July. However, she proved a terrible choice. Her campaigning skills left much to be desired, and more importantly, she showed herself to be even more pro-China than the mainstream of the KMT, which is already far to prepared to accommodate Taiwan’s bullying neighbor. Unsurprisingly, she fell well behind in polls against the candidate of the DPP (Democratic Progressive Party/民進黨), Tsai Ing-wen. A few weeks after Hung was nominated, former KMT official and past presidential candidate James Soong entered the race, making dubious attempts to position himself as a moderate. With a split in conservative support, Hung polled even worse, running far behind Tsai and not that far ahead of Soong, with even their combined support eventually dropping below that of Tsai. Finally, the KMT decided to replace Hung as their candidate, holding a party conference in which Hung was replaced by party chairman Eric Chu by acclamation – in other words, they didn’t even hold a vote.

If there is a recent example from anywhere in the world of a major political party changing their presidential candidate less than half a year before the election, particularly in such a clearly undemocratic manner, I’m not aware of it. What’s more, Chu’s decision to “accept the task” makes a mockery of his past assertions that he would serve out his current term as mayor of New Taipei City (not that he would be the first politician to violate such a pledge). While having Chu as president would not be quite as awful as having Hung, it wouldn’t be any improvement over the current president, Ma Ying-jeou, who’s been pretty bad (Chu has been fairly lousy as our mayor too), and I certainly wouldn’t want to see the KMT get rewarded for their dubious changing of horses in midstream by a victory. I hope Tsai (who is far from perfect, but would at least be a substantial improvement) wins by a substantial margin, even though it’s unlikely to be as much of a landslide as it would have been with Hung as her opponent. Somewhat comically, in the meeting at which Hung was replaced, Chu warned against the possibility that the DPP could win both the presidency and the legislature, claiming that would mean there would be no checks on the DPP’s power. This was rather ironic, since the KMT has held both the presidency and a large legislative majority over the past two terms (not to mention all the years it ruled Taiwan as a one party state before democratization in the 1990s), though it’s certainly true that Taiwanese have suffered due to the lack of checks on the KMT’s power. The best thing that could happen to Taiwan is if the KMT lost power permanently and the main opposition to the DPP came from new forces on the left. While this is unlikely in the immediate future, this election could be a start. As it happens, I am acquainted personally with at least three people running for legislative seats this time. All three are running as outsiders (two as members of small, new progressively-minded parties, and one as an independent), and while it’s far from certain that any of them will get elected, it would certainly be nice to see them and others like them in the legislature to keep the DPP and KMT honest, or at least as honest as they can be, which is not very in the KMT’s case, as its recent actions have once more shown.

Finally, there are actually some elections going on now - those for the Tibetan government in exile. The winners will certainly have a challenging job, not only trying to find a way to deal with China's unending malice, but also trying to fill the Dalai Lama's shoes as leader of the Tibetan people. It's interesting that one candidate for prime minister is openly suggesting that the Dalai Lama's moderate course be abandoned and full independence once again be declared the ultimate goal of the Tibetan people. As much as I respect the Dalai Lama, I think there is something to be said for aiming for independence, and I think it would be good if the Tibetans can have an open discussion about their options.
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