>This article was written by an astronomer working with Kepler, and I wonder why you apparently seem to believe that they are so naive that they forget about the bias in their own research tools.
Exactly. I actually did some research on Weiss.
So she studied astronomy at Harvard where she got her BS, then went on to Cambridge for her masters, and then a PhD from Berkeley. Now she works with NASA.
Odd that all these people who clearly didn't even read the article seem to find supposedly obvious bias and flaws in the research of someone who is clearly among the top young researchers/experts in this field.
When this species becomes capable of observing our feelings objectively and not simply saying "I feel it, it's mine so it must be truth" people like you are going to feel something very different.
Truth != value. Of course my feelings are valuable to me; I don't need them to be true (and I don't even think being true or false _applies_ to judgement values).
"I once heard a wise man say that if anyone
were to know the whole answer, he would cease to exist."
Yes, that's what the "put through a virtual Kepler’s detection scheme" part refers to. So she:
1. Generated a bunch of random planet sizes.
2. Simulated what the detector would have reported for each.
3. Compared those virtual detections against the real detection data.
If the two results had matched, it would imply real solar systems have random planet sizes and the bias they see is from the detector. Since the two results are different, it implies the actual solar systems are not randomly sized with the apparent uniformity coming from detector bias.
(There could, of course, be a third factor where planets are randomly sized but the measured bias comes from something else.)
2. Simulated what the detector would have reported for each.
I think this would be really hard. For example, you need to simulate how the detector responds to different planet compositions, different signal to noise ratios at different distances from the star. A sphere in vacuum model may be a gross simplification.
Well, we already deduce exoplanets' masses, orbits, diameters, and so on from the sensor data that basically amounts to a tiny change in the light curve of the star. The astronomers are probably pretty well aware of the limitations of their models and potential confounders.
How would the composition of a planet affect how much light it blocked of its star when passing in front? And signal to noise ratios are presumably quite easy to simulate. So not really sure what's so hard about it.
Composition determines density. A rocky planet would block less light than a gas giant planet of the same mass, because it would be denser and therefore smaller.
But does density have to do with anything Kepler measures?
Since it only measures how much light decreases, I assumed it's only measuring planet size, and that we're totally ignorant about planet mass and density?
Anything is possible. You can never prove anything. In science/real life true means very likely and false means very unlikely.
So yes the simulation could be wrong, but I guess with everything we know and the error bars the answer was clearly no.
The answer is "no" because the author needs to come to a conclusion for the paper that they are writing. It doesn't matter if they are correct, it matters that they produce a paper, so that's why they came up with this conclusion.
I wish researchers weren't biased to produce papers, it doesn't help us with honestly understanding our universe.
You've got to weigh "we didn't evolve to specifically eat it" against "it didn't specifically evolve to prevent us from eating it". I'm not sure we'll get an answer to which is a bigger factor unless we find some xenobiology and take a bite.
A lot of digestion is pretty elementary, and built upon our stomachs' acid bath -- proteins go in and are unwound and broken down. Most foods that cause problems later down the line contain a protein that both (a) is resistant to the stomach acid, and doesn't break down before hitting the intestines and (b) causes a problem when it hits the intestines.
Barring that - or incorporating elemental poisons like arsenic at levels we can't cope with - I'd personally bet that if you charred a random alien critter over a fire and wolfed it down, it's not crazy that your stomach acids would break down anything that survived the fire and would otherwise harm you, and you'd be able to extract a reasonable mix of sugars, fats and proteins from what you'd ate.
It's not impossible that an entire planet would have some proteins common to all of their lifeforms that both (a) didn't break down easily when cooked or digested and (b) were incredibly lethal to terrestrial life, but there's no ab initio reason to think they would or wouldn't, one way or the other.
The stomach isn't a perfect barrier, there's always something that gets through. If it didn't we wouldn't be able to take drugs orally. Our bodies have an entire subsystem devoted to processing compounds that made it through the main digestive system into the blood stream. The liver is dedicated to metabolizing these substances, in a process literally called "xenobiotic metabolism".
Sure, the odds of a particular compound found in some alien lifeform having a toxic interaction with our bodies is small, but I consider the odds of one of the hundreds of thousands of different types of compounds in that lifeform having a toxic interaction is on the higher side.
Oh, and to be clear, by toxic interaction I don't necessarily mean a poison, per se. It could also have a carcinogenic effect, or if the compound is common enough in the creature and undigestable through the stomach and intestines it could overload the liver, etc.
Yeah, not a perfect barrier, but if it's good enough that I'm not poisoned, do I care? I eat lots of delicious food that doesn't digest optimally.
As for carcinogenic effects, well, depends on what the timelines and cancer-rates you're talking about look like. We eat lots of things on Earth that are mildly carcinogenic over a lifetime, and the fact they are doesn't really stop us.
I don't believe this was an attempt to find bias or noise from the physical sensors, but rather was looking at the method itself.
The method has some known biases that they were ensuring wouldn't explain the given pattern in the data. Depending on the depth of the simulation, it may have also been able to account for some unknown biases in the method.
Now even under your interpretation, I'm curious about which known object you'd suggest they use.
Random question.. If they are looking for transits, doesn't that presuppose the data will find close in planets? I believe that's not the only method, but wouldn't that push more close planets than distant ones? Would it find transits of things like Neptune or Uranus that take hundreds of years?
Thanks for the tip! From the wiki page it does look like the thing I'm describing, and I guess I've encountered it many times but never interpreted it as such.
I was wondering, how can Kepler detect planets like Saturn that take decades to orbit, let alone planets like Uranus or Neptune? Wouldn't we need to be looking for 50 years at least in order to have enough observations to drawn meaningful conclusions?
I wonder if some of the early core functionality such as replication, splitting, energy generation, etc. only has a few simple and effective possibilities? Are there any really simple RNA/protein patters that almost just have to occur from a statistical/mechanical view?
Also in the LIGO project, it's a branch of astrophysics called numeric relativity. The gravity wave signatures predicted by the simulations was what helped confirm the LIGO detections of black hole and neutron star mergers.
I'm not sure the author is taking into account observation time and the orbit diameter of planets.
In other words, it could just be that planets in similar orbits have similar sizes, which would be roughly consistent with our own Solar System.
Jupiter alone takes almost 12 Earth years to get around the Sun. It seems to me that an observer on a remote planet on the same plane as our own Solar System, observing us, would likely only see the inner 4 planets (if anything at all) during a 4 year observation window similar to Kepler.
Although it's science fiction, the second book from the "Three Body Problem" series by Cixin Liu offers an intriguing idea he labels as the "Dark Forest". The gist is that the primary motivation for all civilizations is survival and other civilizations are a threat. This Quora answer gives more detail, but I highly recommend reading the books; there are many compelling science-based ideas within it.
I spoiled this book for myself, and it was still fun. There was a lot of dramatic tension as I waited for all the characters to realize the horrifying things that lay in wait.
That's one way to go about it but it might be a bit simplistic and there's no reason why cooperation wouldn't work out for some civilizations as well. To completely hide one's signals is both hard to achieve and not necessarily beneficial. For example in ancient times there were blooming trades between empires which would not have been possible if every civilization just thought about hiding themselves. I was not a fan of "Three Body Problem" from its beginning.
The planets detected by Kepler will tend to be unusually close to their star due to its detection method. I believe that’s why Sol looks like an outlier in that regard — it’s really that the other systems are the outliers.
Seems likely that the planets with larger orbits have not yet been detected since they will take longer to reach a point in orbit when they are transiting their respective stars. It seems premature for the paper to reach it's conclusion when Kepler has been in operation for less than ten years, but hey... publish or perish.
There could be one factor, or several. What matters is if the species can or cannot survive at the end to spread out or at least to make their presence detectable.
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[ 2.9 ms ] story [ 123 ms ] threadExactly. I actually did some research on Weiss.
So she studied astronomy at Harvard where she got her BS, then went on to Cambridge for her masters, and then a PhD from Berkeley. Now she works with NASA.
Odd that all these people who clearly didn't even read the article seem to find supposedly obvious bias and flaws in the research of someone who is clearly among the top young researchers/experts in this field.
"I once heard a wise man say that if anyone were to know the whole answer, he would cease to exist."
https://books.google.es/books?id=KuFwDwAAQBAJ&lpg=PT181&ots=...
Yes, that's what the "put through a virtual Kepler’s detection scheme" part refers to. So she:
1. Generated a bunch of random planet sizes.
2. Simulated what the detector would have reported for each.
3. Compared those virtual detections against the real detection data.
If the two results had matched, it would imply real solar systems have random planet sizes and the bias they see is from the detector. Since the two results are different, it implies the actual solar systems are not randomly sized with the apparent uniformity coming from detector bias.
(There could, of course, be a third factor where planets are randomly sized but the measured bias comes from something else.)
[1] https://sites.google.com/site/h2g2theguide/Index/i/540914
I think this would be really hard. For example, you need to simulate how the detector responds to different planet compositions, different signal to noise ratios at different distances from the star. A sphere in vacuum model may be a gross simplification.
Since it only measures how much light decreases, I assumed it's only measuring planet size, and that we're totally ignorant about planet mass and density?
I wish researchers weren't biased to produce papers, it doesn't help us with honestly understanding our universe.
Sorry, I guess that wasn't as comforting in print as it was in my head.
A lot of digestion is pretty elementary, and built upon our stomachs' acid bath -- proteins go in and are unwound and broken down. Most foods that cause problems later down the line contain a protein that both (a) is resistant to the stomach acid, and doesn't break down before hitting the intestines and (b) causes a problem when it hits the intestines.
Barring that - or incorporating elemental poisons like arsenic at levels we can't cope with - I'd personally bet that if you charred a random alien critter over a fire and wolfed it down, it's not crazy that your stomach acids would break down anything that survived the fire and would otherwise harm you, and you'd be able to extract a reasonable mix of sugars, fats and proteins from what you'd ate.
It's not impossible that an entire planet would have some proteins common to all of their lifeforms that both (a) didn't break down easily when cooked or digested and (b) were incredibly lethal to terrestrial life, but there's no ab initio reason to think they would or wouldn't, one way or the other.
Sure, the odds of a particular compound found in some alien lifeform having a toxic interaction with our bodies is small, but I consider the odds of one of the hundreds of thousands of different types of compounds in that lifeform having a toxic interaction is on the higher side.
Oh, and to be clear, by toxic interaction I don't necessarily mean a poison, per se. It could also have a carcinogenic effect, or if the compound is common enough in the creature and undigestable through the stomach and intestines it could overload the liver, etc.
As for carcinogenic effects, well, depends on what the timelines and cancer-rates you're talking about look like. We eat lots of things on Earth that are mildly carcinogenic over a lifetime, and the fact they are doesn't really stop us.
The method has some known biases that they were ensuring wouldn't explain the given pattern in the data. Depending on the depth of the simulation, it may have also been able to account for some unknown biases in the method.
Now even under your interpretation, I'm curious about which known object you'd suggest they use.
We and we alone have the one and only Trump ;-)
[0] https://en.wikipedia.org/wiki/Inverse_problem
https://en.m.wikipedia.org/wiki/Numerical_relativity
In other words, it could just be that planets in similar orbits have similar sizes, which would be roughly consistent with our own Solar System.
Jupiter alone takes almost 12 Earth years to get around the Sun. It seems to me that an observer on a remote planet on the same plane as our own Solar System, observing us, would likely only see the inner 4 planets (if anything at all) during a 4 year observation window similar to Kepler.
https://www.quora.com/What-is-the-Dark-Forest-Theory-of-the-...
This aggregate of 'filters' is what's important.