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Ed Hartouni
Trad climber
Livermore, CA
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Feb 11, 2016 - 08:51pm PT
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the BICEP dustup certainly informs the process the LIGO collaboration would have taken before releasing their results.
BICEP had to use data from the Planck collaboration... remember that BICEP measures the polarization of the cosmic microwave background (CMB), Plank measured the tiny fluctuations of the CMB and this information is necessary for interpreting the BICEP data.
For whatever reason, the BICEP collaboration couldn't get the Planck collaboration to release its data, so they went old versions of the data...
this was a big mistake, and it is possible that the BICEP collaboration felt that their competitors might have also been onto the observation, and wanted to publish first establishing priority for the discovery.
The LIGO collaboration took its time to investigate the observation. They were prepared to take their time having been in the game for a long time (decades) and had established a number or protocols for investigating the candidate signals. The signal was first detected on September 14 of last year, and the manuscript was sent to Phys Rev Lett on January 21, 2016, 4 months of work to prepare the manuscript, checking the results, etc... it would have been a really intense time for the collaboration.
The manuscript review took roughly 2 weeks, which is a very short time, but indicates that the collaboration did a very complete job describing their analysis (which shows in the paper) and met all of the criteria for the reviewers to approve, and the editors to decide to publish. The reviewers and the editors were all well aware of the BICEP2 result... and the aftermath.
In contrast, the BICEP2 manuscript took 2 and a half months to review, including revisions required in the review process. In the abstract we find the line:
However, these models are not sufficiently constrained by external public data to exclude the possibility of dust emission bright enough to explain the entire excess signal.
in the section discussing the dust we find:
The main uncertainty in foreground modeling is currently the lack of a polarized dust map. (This will be alleviated soon by the next Planck data release.)
They should have waited.
you can re-read the BICEP2 paper here:
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.112.241101#fulltext
I'll respond to the science question on Moose's thread.
The two experiments, BICEP2 and LIGO are looking at two very different phenomena. LIGO was built to directly observe gravitational waves. BICEP2 was built to see the fluctuations due to gravitational waves on the pre-inflationary universe. It is a very indirect way of informing about gravitational waves... but important for establishing the gravity was around at that time (some theories of gravity imply it emerges from other interactions, ask Largo to ask his car-pool).
What is common to both these experiments is that they represent important discoveries with very deep implications. When the stakes are high, humans act like humans whether or not they are scientists.
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Ed Hartouni
Trad climber
Livermore, CA
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Feb 11, 2016 - 09:21pm PT
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this thread is interesting in its own right, without the superlative announcement of the observation of gravitational waves.
The probability calculations that limpingcrab offers aren't very compelling to me, but there is a good reason, and I'll illustrate it with an example that was evoked by the GW announcement.
Prior to the 1920s we have this beautiful work of Einstein on relativity, the beautiful work on quantum mechanics inspired by a number of physicists, but perhaps lead by Bohr. It was an amazing time when things which had long been a puzzle started to become understood.
But it is fair to say that in that time, one still did not know how one of the most familiar everyday experience could be explained, I'm talking about the Sun. Estimates of what powered the Sun based on science understood prior to the 1920s is simply not possible. Imagine estimating the probability that the Sun could provide so much energy for so long. Your estimate using that science would be zero... nothing known then could explain it.
It took the realization that Einstein's famous E=mc² for physicists to get on the right track, but even then the neutron had to be discovered, nuclei described and nuclear reactions measured to come up with what is our current understanding.
Even this was in question until the recent (within the last 20 years) discovery of neutrino oscillations explained why there were fewer neutrinos (generated by those nuclear reactions) than expected (by a large amount).
We have in the last 60 or 70 years, developed quite an exquisite model of how the Sun produces that wonderful light that warms our faces at sunrise. Before that, it was a total mystery, beyond our ability to calculate.
I see the issue with abiogenesis in exactly the same light, we can do the calculations and come up with some numbers, but we do not know the science that is required, yet, to do a sensible calculation. Saying we "don't know" is not an admission that "anything is possible," it is not an admission that science "cannot explain" the phenomenon, it is simply recognizing that we don't yet know.
I'm a sunny optimist that we'll figure it out, and when we do, the numbers won't look at all that daunting.
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Brokedownclimber
Trad climber
Douglas, WY
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Feb 12, 2016 - 05:43pm PT
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Back to the discussion of what constitutes life. I don't believe response to stimulus is required. You'll have to excuse me on several items, since the last time I studied anything about viruses is now over 50 years ago. What viruses CAN do is self-assemble from components. I'm trying to recall what I learned in my /Special Advanced Topics course in Biochemistry at CU in Boulder my last undergraduate semester.
I'm with Ed, in being less than impressed by the probability calculations.
Moosedrool; Re: Panspermia. Life didn't necessarily begin in cometary matter, it simply is a vehicle of transfer from one solar system to another.
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High Fructose Corn Spirit
Gym climber
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Feb 12, 2016 - 07:14pm PT
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Carl Sagan,
Pale Blue Dot
“The future possibilities of space-travel,” wrote the philosopher Bertrand Russell in 1959,
which are now left mainly to unfounded fantasy, could be more soberly treated without ceasing to be interesting and could show to even the most adventurous of the young that a world without war need not be a world without adventurous and hazardous glory. To this kind of contest there is no limit. Each victory is only a prelude to another, and no boundaries can be set to rational hope.
In the long run, these — more than any of the “practical” justifications considered earlier — may be the reasons we will go to Mars and other worlds.
Chapter 16,
Scaling Heaven
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High Fructose Corn Spirit
Gym climber
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Feb 12, 2016 - 07:22pm PT
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Seems esp suitable to this thread. A bit more Sagan...
"We had an expansive run in the ’60s and ’70s. You might have thought, as I did then, that our species would be on Mars before the century was over. But instead, we’ve pulled inward. Robots aside, we’ve backed off from the planets and the stars. I keep asking myself: Is it a failure of nerve or a sign of maturity?"
A failure of nerve?
A sign of maturity?
Finally,
"There were many possible historical paths. Our particular causality skein has brought us to a modest and rudimentary, although in many respects heroic, series of explorations. But it is far inferior to what might have been—and what may one day be."
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Ghost
climber
A long way from where I started
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Feb 12, 2016 - 07:27pm PT
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F*#kin' scientists man, like don't they have real lives? I mean, if there are gravity waves, like who cares about all that "can they replicate this data" sh#t. The important thing is...
Where are they breaking?
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Ed Hartouni
Trad climber
Livermore, CA
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Feb 12, 2016 - 08:06pm PT
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Albert don't surf...
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limpingcrab
Trad climber
the middle of CA
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Feb 12, 2016 - 08:09pm PT
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I see the issue with abiogenesis in exactly the same light, we can do the calculations and come up with some numbers, but we do not know the science that is required, yet, to do a sensible calculation. Saying we "don't know" is not an admission that "anything is possible," it is not an admission that science "cannot explain" the phenomenon, it is simply recognizing that we don't yet know.
I'm a sunny optimist that we'll figure it out, and when we do, the numbers won't look at all that daunting.
Totally agree that the stats stuff isn't necessarily telling, but it may be for several abiogenisis mechanism hypotheses (muller-urey sort of stuff), and it's kinda nuts that people actually calculate how many ways molecules can bump into each other!
I'm with Ed, in being less than impressed by the probability calculations.
Again, I'm not stuck on it.
Pretend there are no stats. Either way there have been enough hypotheses disproven by scientists promoting another that it is pretty obvious something very unique had to happen for abiotic materials to turn into living things. Based solely on current information I'm not even a tiny bit optimistic that it will turn out to be something so simple and common that it has happened many times across the universe. Wishful thinking and optimism might help people believe otherwise, but it is without evidence that they do so.
PS: Science is still young and I'm ok if everything I've studied turns out to be wrong. I too think it would be awesome if there were aliens, but I'm not going to bet anything on it, including a bunch of government funding that could go elsewhere.
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Ed Hartouni
Trad climber
Livermore, CA
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Feb 12, 2016 - 08:18pm PT
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...but it is without evidence that they do so.
not entirely, one proposes ideas, hypothesizes, and tests... fail, fail better... eventually the essentials are teased out.
I think the more impressive "evidence" is the recurrence of life after the Last Great Bombardment. There is evidence the planet had life prior to that period, which was extinguished during the LGB, and returned after... the LGB sterilized the planet (boiling all the water).
In that particular interpretation, life was gone, then it came back... so it would seem that it's "not such a big deal."
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Brokedownclimber
Trad climber
Douglas, WY
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Feb 12, 2016 - 08:28pm PT
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I have given some thought about something of an updated and more advance Urey-Miller experiment. A reactor with an internal UV source housed in a quartz well, an spark discharge system internally, and containing more than just ammonia, methane, oxygen, traces of water, carbon dioxide and carbon monoxide; should add finely powdered quartz crystals, and hydrogen sulfide; maybe even include a micro ozone generator. Run that sucker at all the presumed different temperatures, and many different combinations and concentrations hypothesized at the early Earth atmospheric composition. My bet is there would be an even more encouraging result for an outcome. Look not only for amino acids, but polynuclear aromatic hydrocarbons and nucleic acids. Ozone is one of the outcomes from UV irradiation of O2.
One of the things I've done professionally over 50 years is making synthetic amino acids, and my reaction gemisch incorporates many elements of known synthetic pathways, just not under conditions to have a predicted outcome.
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High Fructose Corn Spirit
Gym climber
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Feb 12, 2016 - 09:04pm PT
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As presented by Reid Gower for NASA...
I don't know the year, it didn't say, but it conveys a sense of things.
Is this the right mix of values?
Who can say?
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zBrown
Ice climber
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Topic Author's Reply - Feb 12, 2016 - 09:15pm PT
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this thread is interesting in its own right, without the superlative announcement of the observation of gravitational waves.
It is both entertaining and informative (thanks mainly to Dr. Hartouni).
Thanks Mister ... er ... Sorry ... Doctor Ed.
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Brokedownclimber
Trad climber
Douglas, WY
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Feb 12, 2016 - 10:11pm PT
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Here's a very interesting presentation by Dr. Robert Zubrin, to an audience at Ames laboratory, Moffett Filed, CA in 2014.
[Click to View YouTube Video]
I watched this last night, and it really impressed me with the different approach than the "official one."
Realistically, a Mars Program is well within our present capability. I'm certain I would rather see some of the money being thrown at the F 35 fighter ($1.4 Trillion) be diverted to a much more peaceful undertaking. Zubrin estimates this could be done for ~ $50 Billion, and NOT the earlier $480 Billion mentioned back in 1990.
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Dingus McGee
Social climber
Where Safety trumps Leaving No Trace
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Feb 13, 2016 - 03:46am PT
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Broke Down,
Again the $1.4 trillion is over 35 years and may not actually come about to that much spending on that plane. Congress can vote to stop funding anytime and use it on a newer plane. But for your lack of number comparisons skills $1.4 trillion / 35 years = $40 billion/year. You must be a Republican to throw numbers around to the likes of what you present?
the equalizing factor is called cost over runs. So the low dreamed of $50 billion inches towards $500 billion.
the only time somethings gets cheaper is when we buy it from Shina.
Shina to get one year $25 billion deal with USA to put White Boy on Mars.
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Feb 13, 2016 - 06:23am PT
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I've been following Zubrin's ideas for years. Unfortunately his lonely voice of reason isn't heard over the babbles of the earth firsters cowering under the doom scenario du jour.
Yeah Dingus if we want something done its time to look to China. It's there century. They have the will and cohesion of vision the west has lost. They just sustained nuclear fusion in their Tokomak reactor for 102 seconds. They are beginning to rollout commercial grade Gen 4 fission reactors. It's their lead going into the future.
For you frustrated young women out there tired of slackers and the high rate of queer American youths- also head east. The one child policy of China's past has produced as excess of males unable to procure mates.
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Brokedownclimber
Trad climber
Douglas, WY
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Feb 13, 2016 - 07:10am PT
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Politically, I can't stand either major party as presently constituted. I consider myself a Libertarian/Constitutionalist/Independent. I've opposed the F 35 project as failed attempt to build a "one size fits all" aircraft that doesn't actually fulfill any of the roles assigned. The Marines have foisted the VTOL capability on the other services, at the expense of making a good basic design overweight and underpowered. I just used the F 35 as a horrible example of military procurement gone terribly wrong. I believe we could start by putting an additional $10 Billion a year into NASA, and an equal amount into the private sector for 5 years with a mission-directed mandate to get us to Mars with a sustainable base by 2026. As Zubrin commented, a return to the Moon could be a spinoff.
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Brokedownclimber
Trad climber
Douglas, WY
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Feb 13, 2016 - 09:49am PT
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Let's do a reverse process analysis of this problem. Most astronomers concur with the hypothesis that all the water presently on the Earth came here through cometary impacts later in solar system formation. Early and primitive life forms could have been carried along with huge amounts of water; the number of comets required to build the oceans is HUGE. The Kuiper belt of "cosmic building blocks" most likely contains debris from other planetary systems long since destroyed, including water in the form of ice. The numbers keep changing, but take ~ 4.5 Billion years as the age of our solar system, as opposed to ~ 10-12 Billion years as the age of the known universe from the Big Bang, and there have been lots of now vanished planetary systems, destroyed through novae, collisions...whatever. Their debris constituting the interstellar "junk" for new planetary system formation. First generation stars are composed of mostly Hydrogen, Helium, and lower atomic weight elements: Lithium, Boron, etc. Only after the first generation stars go Nova and new stellar systems incorporate some of these elements do we begin seeing Iron, Carbon, Nitrogen, Sulfur, etc. Only when higher generation stars develop solar systems is there a possibility of "life." So...in spite of Limping Crab's statistical analysis, that's a long enough time for an awful lot to happen.
We need to discuss this through an alcoholic haze at CoR this June!
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Gnome Ofthe Diabase
climber
Out Of Bed
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Feb 13, 2016 - 11:31am PT
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Drive by blind posting
[Click to View YouTube Video]
So cool when it fits soo we'll
Carry on,
Oh again , that nagging question....
Why aren't there any humans on the moon?
A major space station. A Platform for reaching to the stars ?
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limpingcrab
Trad climber
the middle of CA
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Feb 13, 2016 - 07:06pm PT
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I think the more impressive "evidence" is the recurrence of life after the Last Great Bombardment. There is evidence the planet had life prior to that period, which was extinguished during the LGB, and returned after... the LGB sterilized the planet (boiling all the water).
In that particular interpretation, life was gone, then it came back... so it would seem that it's "not such a big deal."
Evidence strongly suggests that life started before the LGB and survived a few kilometers down in the earth's crust, where we can still find microbes today (I can provide some papers if anyone wants). Under most scenarios it is unlikely that the LGB heated the planet enough to extinguish that life. Oleg Abramov at the USGS astrogeology center ran models on this stuff and has info available.
The big question is whether or not there was life before the impact that created the moon, because that had more than enough juice to roast all living things on earth. Interestingly, this is a question that Mars can help us with. Mars did not experience any moon-forming impacts like earth did so some scientists want to dig a few km into Mars to look for signs of thermophile bacteria. (I still doubt we'll find any:)
Then the comet would have to land on a planet that has the right conditions for that life to propagate. How likely is that?
Moose, I agree, and would add that panspermia has followers because of how seemingly impossible it was for life to start on earth. Hence, it's probably really rare! But, in the words of Abramov from an old interview I read and just rediscovered while trying to remember his name, “That’s still a big open question,” said Abramov. “We just don’t know if what happened on earth was unique or, given the right conditions, life starts easily.”
I hope I'm wrong, but my personal opinion is that it was unique. I'll probably keep it that way until there is any evidence to the contrary.
Edit to ask: Will someone please explain why you disagree and suspect life to be scattered across the universe? Sorry, I just don't get it.
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