Thursday, December 8, 2016

Our Home

To my conservative friends and family,

I know we disagree on most everything, and these days virtually every one of us, whether we're liberal and conservative, feels like the other side has either 1) been grossly misled by our respective, biased media outlets, or 2) harbors deep antipathy towards the country or to some of the people in it who are not like us. So we have this vast political chasm between us, and it seems hopeless to bridge the gap. We all acknowledge that this is a sorry state of affairs but we just can't fix it. Even so, we remain friends and family, we love each other and we respect each other. We're not going to give up most of our firmly held political views, but we can attempt to listen to each other, trust that our friends and family aren't bad people or stupid people, and every now and then consider that our side maybe has it wrong on something. I certainly do that.

There are many political debates upon which there can be reasonable disagreement. But there can no longer be any rational defense of the position denying that the Earth is warming and that we are causing it. We can debate what is to be done about this situation, but that fact is simply undeniable. Anyone in public office or in the media who says otherwise is either willfully ignorant of the facts or is misleading the public in a way that I believe is truly criminal. And the motive for this could not be more clear: they are either shills for the corporations who fund their campaigns / television programs, or they are pandering to their constituents whose lives currently depend on the fossil fuel industry. While the latter is at least somewhat in line with their duties, the former is simply reprehensible.

We can and should debate the best way to go about mitigating the problem, to do it in a way that strengthens the economy and supports those who must transition to a new line of work. But that requires we all first acknowledge that there is a real problem that must be solved. And once we've done that, we have to keep our eyes on the big picture; transitioning to a clean fuel economy will take some adjustment, no doubt. But so much is at stake. Mass extinctions, permanently flooded cities here and around the world, enormously destructive storms, severe drought and wildfires, radical ecological transformations, major economic upheaval. It's all happening right now.

Under the two party system there can be any number of policy issues on which a partisan can disagree with his or her party. And so there must be Republicans out there who believe global warming is a real threat and want their politicians to stop denying science. Republicans now hold all the power in Washington, so it's up to those inside the party to stand up and do what's right. If you are a Republican who knows the party is wrong on this issue, I beg you to work from within to end this dreary charade.

And to those of you who do not yet believe in global warming -- because it will become even more apparent in the years to come -- I humbly ask that you look again at the weight of the evidence and reconsider your position. Just consider the possibility that it isn't a vast left wing conspiracy, that there are real people (scientists) who do their job diligently and faithfully follow the data wherever it leads. Consider the possibility that Sean Hannity and Jim Inhofe and Scott Pruitt have more to gain from lying to you than The Weather Channel does. Consider the possibility that we are perpetuating an environmental disaster that will make us all pariahs in the eyes of our children and grandchildren. 

We have just one planet to call home, to cherish from now until the extinction of our species. I pray that we have an ocean of time ahead for us. Let us be good stewards of this lovely world while it is ours to protect. Please.

Wednesday, April 6, 2016

Regarding our paper, "A Cloaking Device for Transiting Planets"

This week you may have seen articles about a paper Professor David Kipping and I wrote called "A Cloaking Device for Transiting Planets." If you feel so inclined I would encourage you to read the paper itself (rather than the somewhat accurate but largely incomplete coverage it's gotten in the press). As far as scientific papers go I think it's quite readable for a scientifically literate public audience. It was decidedly outside our main research foci but we whipped it up in very little time while we continued working on other projects. We had a lot of fun with it and I believe it is a worthwhile addition to the SETI literature.

On the whole I have been thrilled with the response that we've gotten. The paper has been discussed on Space.com, the BBC, Popular Science, Discover Magazine, Scientific American, and Gizmodo, to name just a few. The story blew up on Twitter, and our explanation video has garnered more than ten thousand views so far. We've reached readers all over the world, and for myself I think it is an unambiguously positive thing to get a non-scientific audience thinking about exoplanetary science, the search for extraterrestrial intelligence, and whether we ought to try to make contact or, by contrast, try to hide ourselves. For many people it takes something a little provocative to make them pay attention to science and I'm delighted our work got their attention.

Our paper explored the energy requirements of using lasers to distort a transit signal for the purpose of communicating with or cloaking one's presence from an observer in another star system. Crucially, we suggested that other civilizations could be doing this to their transit signal right now. We found the energy requirements to do this for the Earth were remarkably low, within the capabilities of today's technology, and we therefore made the case that an artificial transit profile is very easily achieved by other civilizations and could thus be detected in transit data. Importantly we made no statement about whether we ought to cloak or ought to broadcast our own presence, though many media outlets seemed to think we were advocating for the construction of such a device. We simply ran the numbers and put it out into the world for others to chew on.

Of course we knew that the most provocative aspect of our paper was the notion that we could build a cloaking device for our own planet, and the paper uses the Earth as a concrete example of how one might achieve a transit cloak. We opted to title the paper "A Cloaking Device for Transiting Planets" in part because we knew this aspect would get the most attention and that meant more readers. I suppose we could have called it "A Cloaking and/or Broadcasting Device for Our Planet or Other Planets", but I think the title we went with is the strongest.

I think in retrospect we could have stressed to journalists a greater emphasis on the idea that this is something other civilizations might be doing right now, that we might be able to see signals in the data that could tip us off to other intelligences out there. (Interesting to note: once we realized the main thrust of our paper was getting lost in the mix we doubled down on emphasizing it, but those quotes were routinely left out of the coverage). We see the paper as essentially a SETI paper, but clearly (and understandably) public attention has largely focused on building a cloaking device for the Earth. And while we as science fiction geeks share a kind of enthusiasm for futuristic concepts like a cloaking device for the Earth, I think it's safe to say that as scientists we share the skepticism about the necessity for building such a device on the Earth, at least right now.

Nasty comments about us and our work in the comments sections of the various articles were inevitable, and I certainly don't take them to heart because I stand behind our paper and I know that they've gotten an incomplete picture of our work. Many people lamented the waste of money, though we haven't spent a public dime on this paper. We haven't built anything and there are no plans to do so, and we are both paid through a private institution where we work on a variety of projects. Others suggested we had "a lot of time on our hands", but the truth is David thought up and wrote the core of the paper over the course of a single weekend (when most people are catching up on Netflix), and I'd estimate I spent maybe 10 hours on my part of the paper. We spend the vast majority of our time working on "serious" scientific projects that get much less attention. In any case I suspect that many people making these comments about our paper hold similarly dim views towards other high-profile science projects like the detection of gravitational waves with LIGO or the discovery of the Higgs boson at CERN -- both "serious" science projects that come with very hefty price tags.

I have been more surprised by the negative response from some astronomers, particularly SETI astronomers. I understand that astrophysicists roughly fall into two camps: those who think the search for life elsewhere is a major motivator behind our investigations of the Universe, and those who are really just interested in understanding the physics of the Universe. I of course fall into the first group, but to each their own. Even so I am puzzled by the negative response from those astronomers who actually work on SETI topics. You'd think they would share our enthusiasm for a new potential signal in the data. But I am almost certain that none of them actually read our paper before commenting on it. They may have read an article or two about it, and maybe got a skewed take on it from a journalist calling for a quote. (I've learned that the propagation of information in the media can sometimes be like a game of telephone... the second article borrows from the first, the third from the second, and so on... in the end the information can be wildly distorted). 

Perhaps those critical astronomers think that our paper is less science and more science fiction, but that same criticism is often levied at SETI projects. Or perhaps they think that a paper like ours detracts from "serious" science in the eyes of the public. But again, those in the public who might think our work is a waste of time would probably also balk at the money and time that goes into, say, studying the structure of the Cosmic Microwave Background, and we don't shy away from those investigations for fear of those who don't share our enthusiasm for learning about the cosmos.

The criticism has not be universal, thankfully; our paper has received support from a number of astronomers in the community, including some high profile scientists. I think Professor Avi Loeb at Harvard said it best in the Space.com article:

"If there is a literature of ideas like this one, ideas that people proposed for potential signals that are artificial -- the richer the literature is, the better it is. [...] The moment we find something artificial, it will change everything. It's good to have the imagination at work prior to seeing something unusual, so we are aware that there are possibilities beyond what we expect."

From the beginning we have believed that the question of how we might detect extraterrestrial civilizations, as well as the question about broadcasting or hiding our presence, is a worthwhile question to explore and is something we want the public and scientists alike to think about. Insomuch as our work has sparked that conversation around the world I think we have achieved our objective and then some. And I'll argue as much to any scientist or member of the public who thinks our work lacks merit. Public engagement with science is critical, and papers like ours engage the public imagination in a way many esoteric studies simply cannot. It's also imperative that we not shy away from exploring big questions even if some people fail to see the value. And as for the question of finding extraterrestrial intelligence out there, I continue to believe that such a discovery would be one of the most important of all time. If our work means we're playing even a small role in that process of discovery, I'll be very happy indeed.
"If there is a literature of ideas like this one, ideas that people proposed for potential signals that are artificial — the richer the literature is, the better it is," Loeb said. "The moment we find something artificial, it will change everything. It's good to have the imagination at work prior to seeing something unusual, so we are aware that there are possibilities beyond what we expect." - See more at: http://www.space.com/32423-laser-cloak-could-hide-earth-from-aliens.html?cmpid=514648#sthash.OkDcQDgN.dpuf
"If there is a literature of ideas like this one, ideas that people proposed for potential signals that are artificial — the richer the literature is, the better it is," Loeb said. "The moment we find something artificial, it will change everything. It's good to have the imagination at work prior to seeing something unusual, so we are aware that there are possibilities beyond what we expect." - See more at: http://www.space.com/32423-laser-cloak-could-hide-earth-from-aliens.html?cmpid=514648#sthash.OkDcQDgN.dpuf
"If there is a literature of ideas like this one, ideas that people proposed for potential signals that are artificial — the richer the literature is, the better it is," Loeb said. "The moment we find something artificial, it will change everything. It's good to have the imagination at work prior to seeing something unusual, so we are aware that there are possibilities beyond what we expect." - See more at: http://www.space.com/32423-laser-cloak-could-hide-earth-from-aliens.html?cmpid=514648#sthash.OkDcQDgN.dpufFrom the beginning we have believed that the question about broadcasting or hiding our presence, as well as the question of how we might detect extraterrestrial civilizations, is a worthwhile question to explore and is something we want the public to think about. Insomuch as our work has sparked that conversation around the world I think we have achieved our objective and then some. And I'll argue as much to any scientist or member of the public who thinks our work lacks merit. Public engagement with science is critical and we shouldn't be shy about exploring big questions even if some people fail to see the value. And as for the question of finding extraterrestrial intelligence out there, I continue to believe that such a discovery would be one of the most important of all time. If our work means we're playing even a small role in that process of discovery, I'll be very happy.