Saturday, August 30, 2014

I should post more often, I know..

The trick is how to divide time between podcasting and blogging - time that is left over after work, Krav Maga, domestic chores and family time. Not to mention, the European club football season has started up again and some other projects are in the works...

Anyway, there should be a burst of blog activity soon as the podcasting season winds down at the end of November. We have a four person team working on the Wow! Signal now, and the intent is that this bears fruit in terms of more and better episodes, some of which will have little, if any, involvement by me. I want to write about the Long Delay Echoes soon, and I will also have an interview with Duncan Lunan on the podcast on that very topic.

As for API Case Files, the plan is to get that completely independent of me in the long run, except for my few minutes of Unidentified Science in each episode. I really enjoy doing Unidentified Science, and it is helping me to connect with link minded people all over the place. I hope you will listen.

Wednesday, May 7, 2014

The Fermi Paradox, Part 2

In my first post on the Fermi Paradox, I went over the basics, which I expect most readers are familiar with anyway. It can be summed up simply (perhaps over-simply) as:
  • Our galaxy is plenty old enough for at least one advanced civilization to have completely colonized it by now, even at speeds much slower than the speed of light.
  • "Completely colonized" should include our solar system.
  • No one can make a persuasive case that this has happened.
 So, the simple version is: they should be be here, but they aren't. This presents us with a paradox.

I'd bet that some readers already have a few objections to the above, and over the next few posts we will take this apart and see where reasonable doubt lies.  This is the real value of the paradox: it serves as superb mental lens that makes us question our assumptions. It should make us more humble about our understanding of how the universe works, and spur us into deeper research. The great unknown is great indeed, so let's go explore. The forward path for the human adventure could not be clearer, and one of the best signposts is the Fermi Paradox.

Sadly, this is not the only effect it has. Too many seize on the Fermi Paradox to jump to Grand Conclusions not in evidence. I promise not to do that. Instead, we will look for better questions than "where is everybody?" I haven't found one yet, but I see hope.

Wednesday, January 22, 2014

The Case for the Wow! Signal

I recommend Robert Gray's book The Elusive Wow! if you want detailed background on the Wow! event of August 15th 1977. The book also describes the author's efforts to replicate the signal. To date, no one has reported a reliable second detection of the Wow! Signal, although efforts to find it have not been persistent.

The Wow! Signal was a single 72 second event detected by the Big Ear radio telescope operated by Ohio State University, which was sweeping past the constellation Sagittarius at the time. This telescope was designed to conduct a survey of the radio sky, not to study individual sources in detail. The survey was successful and a number of new radio sources were discovered. After that, some of the science team thought that a SETI search would be a good use of the telescope.

I think the case against the Wow! Signal as an ET beacon is well known.

We are all well aware of the fallacy of the argument from ignorance. Just because the Wow! Signal has not been proven to be from a known source doesn't mean it's from ET. It's possible that the Wow! Signal was some sort of strange problem with the Big Ear's receiver that only occurred once, or that it was an extraordinarily elaborate and strenuous hoax. For these reasons, you would need to see independent confirmation, and we haven't; Robert Gray's single-handed and largely self-funded efforts to do so have been far from comprehensive.

Since the Wow! Signal was discovered after the fact, when Jerry Ehman went through a stack of printouts, it was too late to get another radio telescope to break off what it was doing, swing over and confirm the signal.  The signal was never confirmed, and no similar signal has been found in that region of space.

The are multiple reasons we think that the Wow! Signal may have been an ET beacon.

Tuesday, December 31, 2013

Where I am on the Drake Equation at the end of 2013

I'm sure you are all familiar with the Drake Equation. It's straightforward: SETI scientist Frank Drake devised it as a way to estimate the number of alien civilizations in our galaxy that we might be able to detect. It's only intended to be a rough guide, and has survived the last 50 odd years because it serves as a good way to divvy up the questions we will need to resolve to answer the bigger question, "Are we alone"?

There are many fine explanations of the terms of the Drake Equation easily available to you, so I won't repeat them. Here are few:

This is how the equation is usually written:

N = R* • fp • ne • fl • fi • fc • L

As we move from left to right across the equation, the terms become less and less well known and harder to estimate, even when we know more. The only thing we're sure of with some of the terms is that none of them are zero, since we are here.

In the last few years, there has been progress. We have gone from knowing just the first term with any kind of accuracy ( a factor of 2 or so), to having solid estimates of the first three terms, and we can now begin to conceive of a research program that would give us an estimate of the fourth term.

Remember, we are only interested in rough numbers here: we just want to know, is N a lot or a little?

So, for 2013, I think we are here:


When is absence of evidence = evidence of absence?

You often hear the old mantra "absence of evidence is not evidence of absence," but I think that this is an oversimplification. The truth is, sometimes it is, and sometimes it isn't. It depends on the experiment, and also how well you understand the implication of the results.

There are times when you can make an excellent case that something is absent because there is no evidence of it. If you are is small, well-lit room, you probably don't need to look under many things to convince any reasonable person that there is no tiger there. In general, you need two things:
  1. You need a solid argument for what sort of evidence you would expect if what you are looking for is there, and how that would be different from the null hypothesis (not there). 
  2. A set of data that tends to falsify the hypothesis, thus advancing the null hypothesis.
We're not talking about "proof" here. I would just as soon we not talk about proof much at all, unless the topic is logic or mathematics. Rather, it raising or lowering the odds of the null hypothesis, i.e. that the claim in question is not true.