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[Music]

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[Applause]

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I just wanted to point out like if

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astrobiology successful what we're

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actually going to accomplish which is

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adding a new cosmological parameter to

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our understanding of the universe which

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I think effectively Eddie was trying to

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get at by expanding our horizons and

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thinking beyond the solar system but I

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think it's really important to kind of

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understand the context of our science in

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sort in terms of the scope of what has

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been accomplished in the past as far as

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our understanding of the natural world

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and where we're going and so the way I

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think about astrobiology really is in

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terms of a probabilistic framework about

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what is the percentage of living matter

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that the universe actually can support

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and can we constrain that as

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astrobiologists and how will we do that

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quantitatively and so this is trying to

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move into quantitative frameworks for

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astrobiology and thinking more about our

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biology as a quantitative science and a

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theoretically driven science than one

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just based on sort of anthropic

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perspectives that we have about life on

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Earth and so there's a long tradition

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obviously of people asking the question

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what is life and trying to think about

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it from a definitional perspective

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particularly in our field and that's

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gotten us really far but I think that we

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really need to challenge ourselves at

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this stage in our biology to really

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think about what life is but not from a

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definitional framework but from a

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quantitative one and so there's a lot of

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people that have quoted or in sronger

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over the years as far as his framework

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for what his life and thinking about

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that but my favorite part of that book

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is absolutely the one of the last things

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he says in the book about a plea for

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other laws of physics that there's

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really something missing from our

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understanding of the way the world works

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and how we can actually understand

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ourselves in terms of new principles or

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laws that are actually necessary to

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explain life

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so what astrobiology really needs to get

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at the question what is life is to

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really start thinking about quantitative

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approaches and not just definitions but

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ways that we can actually quantify bio

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signatures in the way that have been

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presented so far but also combining that

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with new ways of trying to understand

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what life is fundamentally and then

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unifying how we think about that not

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just from the perspective of bio

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signatures but how we think about it for

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origins science or across all of the

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astrobiology disciplines so the question

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what is life is all that was really hard

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but there are some things life does that

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no other physical processes in the

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universe do right so we don't know of

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any other kind of physical process that

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can launch that

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into space I say this process of anti

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chrétien that David Grinspoon has been

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talking about is a biological process

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it's an interesting process and that

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actually requires information it

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requires technological civilization like

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our own that has some sort of knowledge

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in it and so to me that suggestive of

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what life is and actually informs kind

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of new principle is the same thing with

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thinking about certain elements in the

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periodic table that couldn't be produced

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without technology all right but

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technology is not usually thought of as

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a physical process we don't think about

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intelligence as a physical thing we

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don't think about it as something to be

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discovered in the universe but that's

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really what the mission of astrobiology

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is so obviously in bio signature science

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we've been doing this for quite a while

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we've been thinking what are the

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signatures what are the things that we

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think biology can uniquely produce and

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so really what we've been doing

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astrobiology right along is reframing

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the question from what is life to what

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does life do and what does life produce

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and I think we're at a stage with asking

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that question that we can really not

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just think about what does life do as a

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bio signature as the signatures of known

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life but also use the new frameworks

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that people have been talking about in

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the session so far and that we're going

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to hear about all week to think about

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reframing the question of what life is

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itself I'm going to give a couple

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examples of that later in my talk so

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we've obviously been think about this

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question how do we search for life in

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terms of what does life produce and Eddy

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already introduced this series of papers

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that came out last year on exoplanet bio

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signatures I'm going to talk about that

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a little bit more from this quantitative

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framework perspective so when we're

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think about what life produces there's

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always the problem of the fact that some

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things like producers can be produced by

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nonliving processes so we can be fooled

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and so it could absolutely fool us and

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we know this really clearly now from all

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the examples of false positive bio

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signatures that we have and so Eddie

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walked through on some really nice

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examples of that but one of the things a

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quantitative framework allows us to do

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is not say that this thing is absolutely

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indicative of life and this one is not

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indicative of life we need to think

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about this thing is having a statistical

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likelihood of being produced by life

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that's higher than the likelihood of it

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not being produced by life and so this

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is the motivation for thinking

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statistically that in order to tweeze

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out the certainty that something is

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actually a biological process we have

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knowledge the fact that biology can't do

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anything that physics and chemistry

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can't do unless you get to a

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technological civilization you require

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extra information and intelligence we're

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talking about small molecule bio

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signatures physics and chemistry alone

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can produce most of those so we have to

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understand what is it that biology does

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above and beyond that and how do we

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actually quantify that so if we're

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thinking about these things it's not

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just the constraints from the fact that

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we have false positives that a dead

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planet can fool us but we also have

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another set of constraints that's really

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hard is that our observational

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constraints especially with exoplanets

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this issue is critical because we get

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very limited data and we don't even have

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certainty of what we're measuring right

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we have statistical models that might

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produce a given observable and we may

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have some likelihood that that

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observable is consistent with our

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framework and so we need to really move

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to not just thinking statistically about

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bio signatures for bio signatures sake

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but also in terms of observational

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constraints and so a number of us got

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together as part of this nexus and of

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initiative to try to think

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quantitatively about bio signatures and

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came up with a Bayesian framework for

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life detection there's a lot of

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different statistical methods you could

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use to think about detecting life but

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this is just one of them and so the

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basic idea is that we really need to

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think about astrobiology from a more

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unified approach and try to think about

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how do we actually say with a high

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confidence level as Sarah was indicating

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that we have detected life rather than

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not life which means we need a

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conditional probability of life being

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produced from that particular set of

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observational data now the compounding

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factor is that a certain set of data

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might also be produced abiotic ly so we

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have a probability that the same

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observational data might be produced by

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a nonliving process and so if you really

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want to have something that's a very

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detectable bio signature or a techno

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signature it needs to be something where

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the probability that it was created by

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life is higher than the probability it

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was created by not life and so what we

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need to do as a community is try to

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figure out what are those things what

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are those observables that give us high

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confidence that we're actually looking

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at a sample of life and the interesting

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thing about this framework is that

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doesn't matter for looking at a bio

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signature about morphology or by

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signature about chemistry they can all

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go into the same quantitative framework

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and so we really need to think about all

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the observables as Dave was saying that

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we possibly can gather to increase the

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likelihood that the particular

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observation was produced by life and not

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a nonliving process so I want to go back

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to this idea of thinking about how we're

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actually constraining the probability of

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life so one of the problems is that we

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don't have an a priori probability we

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don't actually know what the likelihood

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of life in the universe is all right so

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I think I think this is something that

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in the astrobiology community we don't

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think about enough because we like to

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make wild speculation that life is

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common or that life is you know gonna

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look like us but the truth of the matter

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is we don't know we don't know if we're

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the only life in the universe and that's

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actually empowering just as an

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astrobiology community if we think about

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that from the proper perspective of the

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fact that we really need to think very

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rigorously about this problem because we

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don't know what we're looking for we

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don't know what life is going to be like

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on other worlds we don't even know if it

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exists and so we need to start bounding

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what we think the likelihood of the

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process is what we think that thing is

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I'm trying to think about it from both

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sides so one way I like to think about

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astrobiology is that it's not like we

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really have sub disciplines that are

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tackling separate problems so we have

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people that do study that are looking

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for intelligent life and people that do

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origins of life research but really all

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of us are kind of interested in this

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common understanding of what life is in

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the universe and how we can actually

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understand if we're alone and I think

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that if we actually try to unify our

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perspectives a little bit more that we

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actually can make more meaningful

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progress and so you can think about it

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from their perspective of looking for

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another example of life that's one way

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of constraining the likelihood or the

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understanding the probabilities for life

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so for example if we do have a

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statistical ensemble of exoplanets and

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we don't know if there's actually life

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on any of those worlds but we have some

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confidence that life might be on those

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worlds we don't know which world that

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actually constrains the probability for

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life existing in the universe in a way

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that we don't know now and gives us

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someone in knowledge and information on

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the planetary context in which life is

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actually likely to emerge from the other

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side if we start trying to make life in

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the lab under conditions of early Earth

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but just expanding

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something you have alternative

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00:09:01,079 --> 00:08:58,690
chemistry's for life in the lab or

280
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eternity of chemical contacts for life

281
00:09:05,130 --> 00:09:03,070
we start to actually think about the

282
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principles that underlie life that can

283
00:09:09,630 --> 00:09:06,670
actually inform the probability of life

284
00:09:10,320 --> 00:09:09,640
from the other perspective and so one

285
00:09:12,389 --> 00:09:10,330
thing I think is really interesting

286
00:09:14,430 --> 00:09:12,399
thinking about bio signature science and

287
00:09:16,560 --> 00:09:14,440
this kind of quantitative perspective is

288
00:09:18,030 --> 00:09:16,570
that it starts to get bio signatures

289
00:09:19,680 --> 00:09:18,040
more intimately related to other areas

290
00:09:21,120 --> 00:09:19,690
of astrobiology and one of the ones I

291
00:09:24,360 --> 00:09:21,130
like to think about a lot is origins of

292
00:09:26,370 --> 00:09:24,370
life and the fact that if we had a real

293
00:09:27,720 --> 00:09:26,380
theory or a real quantitative framework

294
00:09:29,699 --> 00:09:27,730
for the origins of life we would

295
00:09:30,750 --> 00:09:29,709
actually have a predictive framework for

296
00:09:32,639 --> 00:09:30,760
thinking about life on other worlds

297
00:09:34,769 --> 00:09:32,649
which is not something that we have

298
00:09:36,060 --> 00:09:34,779
right now but this is really going to

299
00:09:37,560 --> 00:09:36,070
require a merger of theory and

300
00:09:38,699 --> 00:09:37,570
experiment in a way astrobiologists

301
00:09:40,829 --> 00:09:38,709
haven't been able to accomplish before

302
00:09:42,889 --> 00:09:40,839
and I think we're on that horizon so

303
00:09:45,000 --> 00:09:42,899
this actually image came out of a

304
00:09:46,470 --> 00:09:45,010
workshop at Carnegie a couple years ago

305
00:09:48,660 --> 00:09:46,480
and reekin sexualizing the origins of

306
00:09:49,889 --> 00:09:48,670
life which was to the point of trying to

307
00:09:51,420 --> 00:09:49,899
think about merging theory and

308
00:09:53,490 --> 00:09:51,430
experiment in a more meaningful way and

309
00:09:54,930 --> 00:09:53,500
I just give you an example of what that

310
00:09:56,490 --> 00:09:54,940
might look like you can think about the

311
00:09:57,930 --> 00:09:56,500
fact that a lot of the kinds of

312
00:09:59,550 --> 00:09:57,940
chemistry that people are doing now in

313
00:10:01,019 --> 00:09:59,560
origins of life is moving towards sort

314
00:10:03,240 --> 00:10:01,029
of quote/unquote messy chemistry

315
00:10:04,500 --> 00:10:03,250
approaches thinking statistically about

316
00:10:06,449 --> 00:10:04,510
the chemistry that might have given rise

317
00:10:07,889 --> 00:10:06,459
to life and so if you think about the

318
00:10:09,420 --> 00:10:07,899
fact that you have some kind of messy

319
00:10:12,930 --> 00:10:09,430
chemical soup and this experiment came

320
00:10:14,400 --> 00:10:12,940
from leek Cronin's lab you can actually

321
00:10:17,670 --> 00:10:14,410
think about whether you could actually

322
00:10:19,019 --> 00:10:17,680
distinguish a chemical system from

323
00:10:20,579 --> 00:10:19,029
another chemical system based on its

324
00:10:22,050 --> 00:10:20,589
history this is not even talking about

325
00:10:23,519 --> 00:10:22,060
life but you can actually talk about the

326
00:10:24,630 --> 00:10:23,529
historical context of like the different

327
00:10:26,610 --> 00:10:24,640
minerals and things that we're out of

328
00:10:27,900 --> 00:10:26,620
the chemistry and start to say that you

329
00:10:29,610 --> 00:10:27,910
actually can distinguish chemistry's

330
00:10:31,260 --> 00:10:29,620
based on their history now think about

331
00:10:32,340 --> 00:10:31,270
that in a planetary context imagine

332
00:10:33,480 --> 00:10:32,350
you're doing these kind of origins of

333
00:10:34,800 --> 00:10:33,490
life experiments but you're actually

334
00:10:36,840 --> 00:10:34,810
looking at the diversity of planets that

335
00:10:38,250 --> 00:10:36,850
we have from other areas of astrobiology

336
00:10:40,019 --> 00:10:38,260
environments that we know about origins

337
00:10:40,920 --> 00:10:40,029
of life it gives us some constraints on

338
00:10:42,210 --> 00:10:40,930
what kind of chemistry's and

339
00:10:46,560 --> 00:10:42,220
complexities of chemistry we should

340
00:10:48,710 --> 00:10:46,570
expect on those worlds we don't have any

341
00:10:50,939 --> 00:10:48,720
large-scale experiments in astrobiology

342
00:10:52,710 --> 00:10:50,949
this experiment I'm showing on this

343
00:10:54,000 --> 00:10:52,720
slide is something from the particle

344
00:10:55,560 --> 00:10:54,010
physics community it's super coming a

345
00:10:58,079 --> 00:10:55,570
conde which is neutrino physics

346
00:11:01,350 --> 00:10:58,089
experiment this experiment is designed

347
00:11:03,240 --> 00:11:01,360
to bound the proton to Craver II so if

348
00:11:06,090 --> 00:11:03,250
you think about proton decay it's never

349
00:11:07,560 --> 00:11:06,100
been observed so we have an experiment

350
00:11:08,560 --> 00:11:07,570
that's basically trying to look for

351
00:11:10,720 --> 00:11:08,570
something that we don't

352
00:11:11,980 --> 00:11:10,730
no physical exists it's motivated by

353
00:11:13,600 --> 00:11:11,990
theory we have some theories that

354
00:11:15,280 --> 00:11:13,610
predict that process might exist in the

355
00:11:17,410 --> 00:11:15,290
universe and what we're doing with this

356
00:11:19,990 --> 00:11:17,420
experiment it was rebuilt a large volume

357
00:11:21,820 --> 00:11:20,000
of water to look for proton decay and

358
00:11:23,320 --> 00:11:21,830
every time we don't observe the event we

359
00:11:25,810 --> 00:11:23,330
have a bound on the probability of that

360
00:11:27,040 --> 00:11:25,820
event happening in the universe imagine

361
00:11:29,620 --> 00:11:27,050
if we did this with an Origin 'life

362
00:11:30,940 --> 00:11:29,630
experiments right and we actually took

363
00:11:33,130 --> 00:11:30,950
those kind of ensemble statistic

364
00:11:34,510 --> 00:11:33,140
approaches to thinking about messy

365
00:11:35,920 --> 00:11:34,520
chemistry's and their likelihood for

366
00:11:37,810 --> 00:11:35,930
life didn't constrain them by our

367
00:11:39,910 --> 00:11:37,820
anthropocentric biases about what we

368
00:11:43,630 --> 00:11:39,920
think life is and like chemistry do what

369
00:11:46,090 --> 00:11:43,640
it does on planets in the lab and we

370
00:11:47,470 --> 00:11:46,100
bound the process we at least can look

371
00:11:49,090 --> 00:11:47,480
at the probability we can connect

372
00:11:50,590 --> 00:11:49,100
origins of life science to exoplanet

373
00:11:52,390 --> 00:11:50,600
science and we can find ways of thinking

374
00:11:57,010 --> 00:11:52,400
quantitatively about bio signatures in

375
00:11:59,140 --> 00:11:57,020
those experiments the main point of this

376
00:12:01,060 --> 00:11:59,150
is that our experiments both in absolute

377
00:12:03,220 --> 00:12:01,070
observations in terms of how we're doing

378
00:12:05,140 --> 00:12:03,230
observations now with exoplanets they're

379
00:12:06,310 --> 00:12:05,150
they're based on likelihoods that we

380
00:12:08,740 --> 00:12:06,320
think that you know this is the most

381
00:12:10,960 --> 00:12:08,750
likely observation they have statistical

382
00:12:12,460 --> 00:12:10,970
errors associated both experimental and

383
00:12:14,380 --> 00:12:12,470
the fact that we're just constrained in

384
00:12:16,000 --> 00:12:14,390
the limited data that we can take and

385
00:12:17,950 --> 00:12:16,010
the experiments that we're doing in the

386
00:12:19,120 --> 00:12:17,960
lab now for origins of life hit least

387
00:12:21,820 --> 00:12:19,130
the most cutting-edge ones for my

388
00:12:23,740 --> 00:12:21,830
perspective they're all statistical so

389
00:12:25,000 --> 00:12:23,750
what we need to do is build statistical

390
00:12:26,770 --> 00:12:25,010
frameworks for biosignatures

391
00:12:28,690 --> 00:12:26,780
we have a statistical framework for

392
00:12:30,310 --> 00:12:28,700
assessing the likelihood of life and now

393
00:12:31,600 --> 00:12:30,320
building into that framework we need to

394
00:12:32,980 --> 00:12:31,610
think more statistically about the bio

395
00:12:34,600 --> 00:12:32,990
signatures that were actually developing

396
00:12:36,100 --> 00:12:34,610
and use them to motivate more

397
00:12:38,890 --> 00:12:36,110
understanding of what we're thinking

398
00:12:40,030 --> 00:12:38,900
about as far as life what life is and so

399
00:12:41,290 --> 00:12:40,040
one way to think about this that might

400
00:12:42,610 --> 00:12:41,300
be more familiar to most people in this

401
00:12:44,680 --> 00:12:42,620
room is just to acknowledge the fact

402
00:12:46,480 --> 00:12:44,690
that life is an emergent property right

403
00:12:47,830 --> 00:12:46,490
nobody in this room has individual atoms

404
00:12:49,150 --> 00:12:47,840
that are alive but we're all alive as

405
00:12:52,150 --> 00:12:49,160
sort of collections of atoms that are

406
00:12:53,770 --> 00:12:52,160
interacting molecules interacting so the

407
00:12:55,540 --> 00:12:53,780
quantitative observables of you is a

408
00:12:58,150 --> 00:12:55,550
living entity to talk about how alive

409
00:12:59,830 --> 00:12:58,160
you are must be things that are emergent

410
00:13:01,960 --> 00:12:59,840
properties they have to be statistical

411
00:13:05,100 --> 00:13:01,970
in nature life is a statistical

412
00:13:07,060 --> 00:13:05,110
phenomenon it's a macro scale phenomena

413
00:13:08,320 --> 00:13:07,070
so we need to think about it from that

414
00:13:09,550 --> 00:13:08,330
perspective and we need to start

415
00:13:11,560 --> 00:13:09,560
developing bio Spooner's does that

416
00:13:13,150 --> 00:13:11,570
really quantify that I think one of the

417
00:13:14,740 --> 00:13:13,160
things anything sara touched on this a

418
00:13:16,540 --> 00:13:14,750
little bit is not to think about

419
00:13:18,550 --> 00:13:16,550
something as measuring you know this

420
00:13:20,230 --> 00:13:18,560
thing's life or this thing's no life but

421
00:13:21,020 --> 00:13:20,240
you can assign a likelihood to it being

422
00:13:24,260 --> 00:13:21,030
life and actually

423
00:13:26,180 --> 00:13:24,270
it's not even quite that that's the most

424
00:13:27,500 --> 00:13:26,190
interesting thing about it it's actually

425
00:13:29,510 --> 00:13:27,510
that you could talk about how alive a

426
00:13:30,740 --> 00:13:29,520
system is some systems are just more

427
00:13:32,060 --> 00:13:30,750
alive than others this is like the

428
00:13:33,860 --> 00:13:32,070
nature of the origin of life transition

429
00:13:35,750 --> 00:13:33,870
it didn't go from non-life to life there

430
00:13:37,310 --> 00:13:35,760
a gradation of stages in between and so

431
00:13:39,050 --> 00:13:37,320
we need to figure out how to quantify

432
00:13:43,190 --> 00:13:39,060
those stages we need to understand how

433
00:13:45,110 --> 00:13:43,200
we can actually measure it so one of the

434
00:13:45,980 --> 00:13:45,120
things that my group's been doing is

435
00:13:47,840 --> 00:13:45,990
actually thinking about something called

436
00:13:49,610 --> 00:13:47,850
plant we calling nominally planetary

437
00:13:51,950 --> 00:13:49,620
systems biochemistry but really think

438
00:13:53,210 --> 00:13:51,960
about life at a planetary scale and

439
00:13:54,740 --> 00:13:53,220
using all of the data that we have

440
00:13:56,150 --> 00:13:54,750
across biochemistry on earth to really

441
00:13:59,120 --> 00:13:56,160
understand what the statistical

442
00:14:00,770 --> 00:13:59,130
properties of biochemistry are and so

443
00:14:02,270 --> 00:14:00,780
this necessitates kind of going to an

444
00:14:03,800 --> 00:14:02,280
abstract approach so we can look at

445
00:14:05,000 --> 00:14:03,810
planet Earth and we can necessarily see

446
00:14:06,470 --> 00:14:05,010
it's alive because we have some

447
00:14:08,840 --> 00:14:06,480
subjective notion of what we think life

448
00:14:10,310 --> 00:14:08,850
is but the whole point of astrobiology

449
00:14:12,440 --> 00:14:10,320
is if we look at another world it might

450
00:14:14,240 --> 00:14:12,450
be alive and we might look at it and we

451
00:14:16,040 --> 00:14:14,250
might not recognize it so we actually

452
00:14:18,560 --> 00:14:16,050
have to look at the patterns and the

453
00:14:21,080 --> 00:14:18,570
data and understand what it is about

454
00:14:22,310 --> 00:14:21,090
that system that's alive and I think

455
00:14:23,990 --> 00:14:22,320
that those things are necessarily going

456
00:14:25,280 --> 00:14:24,000
to be some kind of abstract mathematical

457
00:14:26,600 --> 00:14:25,290
principle and the only example I can

458
00:14:28,190 --> 00:14:26,610
give you that really like resonates for

459
00:14:29,480 --> 00:14:28,200
me it's just to think about the fact

460
00:14:31,820 --> 00:14:29,490
that we're all bound to the planet right

461
00:14:34,670 --> 00:14:31,830
now by gravity right does anybody not

462
00:14:36,830 --> 00:14:34,680
bound by gravity okay good all right so

463
00:14:39,080 --> 00:14:36,840
we all day the laws of physics right but

464
00:14:40,250 --> 00:14:39,090
you don't intuitively obviously think

465
00:14:41,660 --> 00:14:40,260
about the fact that you're sitting in

466
00:14:43,130 --> 00:14:41,670
your chair right now and not floating

467
00:14:45,860 --> 00:14:43,140
off into space because the space around

468
00:14:46,910 --> 00:14:45,870
you is curved right it's because of the

469
00:14:48,860 --> 00:14:46,920
curvature in space and time that's a

470
00:14:50,090 --> 00:14:48,870
pretty abstract concept and I think

471
00:14:51,920 --> 00:14:50,100
we're looking at life we have to think

472
00:14:53,060 --> 00:14:51,930
in similar levels of abstraction and so

473
00:14:54,440 --> 00:14:53,070
one of the ways that we've been doing it

474
00:14:56,630 --> 00:14:54,450
to quantify it it's actually think in

475
00:14:58,220 --> 00:14:56,640
terms of network properties a network is

476
00:14:59,780 --> 00:14:58,230
a really nice representation because it

477
00:15:01,610 --> 00:14:59,790
allows you to talk about the statistical

478
00:15:04,220 --> 00:15:01,620
properties of a system as it's organized

479
00:15:05,540 --> 00:15:04,230
and so in this particular network that

480
00:15:07,670 --> 00:15:05,550
I'm showing here this is a network

481
00:15:09,020 --> 00:15:07,680
representation of the biosphere well you

482
00:15:10,250 --> 00:15:09,030
mean by that is this is all of the

483
00:15:11,720 --> 00:15:10,260
biochemistry that's known

484
00:15:14,060 --> 00:15:11,730
that's cataloged in the Kyoto

485
00:15:15,860 --> 00:15:14,070
encyclopedia of genes and genomes in

486
00:15:17,630 --> 00:15:15,870
each mall each node in the network is a

487
00:15:19,850 --> 00:15:17,640
molecule and it's connected to by other

488
00:15:22,220 --> 00:15:19,860
molecules if it participates in a common

489
00:15:24,080 --> 00:15:22,230
reaction you can be part of a social

490
00:15:25,370 --> 00:15:24,090
network in the sense that all of you

491
00:15:27,080 --> 00:15:25,380
could be nodes in a social network like

492
00:15:28,670 --> 00:15:27,090
on Twitter if anybody's tweeting right

493
00:15:30,350 --> 00:15:28,680
now and you could be connected by other

494
00:15:31,400 --> 00:15:30,360
people by liking them that allows you

495
00:15:32,910 --> 00:15:31,410
just to study the statistical

496
00:15:33,900 --> 00:15:32,920
regularities in that system

497
00:15:35,069 --> 00:15:33,910
it allows you to say some of the

498
00:15:37,169 --> 00:15:35,079
emergent properties in terms of the

499
00:15:38,789 --> 00:15:37,179
organization and so one of the things

500
00:15:41,460 --> 00:15:38,799
that we've been able to show is that if

501
00:15:44,699 --> 00:15:41,470
you look at biochemistry on planet Earth

502
00:15:47,309 --> 00:15:44,709
it is statistically very regular it has

503
00:15:49,499 --> 00:15:47,319
very regular Network properties in terms

504
00:15:51,299 --> 00:15:49,509
of fact if you look at networks of what

505
00:15:54,299 --> 00:15:51,309
reactions and individual organism

506
00:15:56,780 --> 00:15:54,309
catalyzes an ecosystem catalyzes or the

507
00:16:00,419 --> 00:15:56,790
planet as a living entity as a biosphere

508
00:16:02,099 --> 00:16:00,429
catalyzes they have the same structural

509
00:16:03,599 --> 00:16:02,109
properties in terms of their network

510
00:16:05,579 --> 00:16:03,609
representation that scale is a function

511
00:16:08,069 --> 00:16:05,589
of the number of compounds and it's

512
00:16:09,599 --> 00:16:08,079
different than random chemistry now the

513
00:16:10,949 --> 00:16:09,609
point of this in terms of a statistical

514
00:16:12,359 --> 00:16:10,959
framework is that once you know what

515
00:16:14,069 --> 00:16:12,369
those kind of scaling relations are you

516
00:16:14,909 --> 00:16:14,079
have a quantitative rule you can

517
00:16:17,340 --> 00:16:14,919
actually start talking about

518
00:16:18,689 --> 00:16:17,350
statistically distinguishing systems so

519
00:16:20,340 --> 00:16:18,699
if I'm one thing we've been able to show

520
00:16:21,720 --> 00:16:20,350
is if you just look at the patterns and

521
00:16:23,220 --> 00:16:21,730
the reactions in a network you can

522
00:16:24,929 --> 00:16:23,230
statistically distinguish anarchie

523
00:16:25,889 --> 00:16:24,939
a--from a bacteria you don't need to

524
00:16:26,789 --> 00:16:25,899
know anything about the chemistry

525
00:16:28,079 --> 00:16:26,799
they're doing you just need to know

526
00:16:29,819 --> 00:16:28,089
about the patterns the statistical

527
00:16:32,729 --> 00:16:29,829
patterns and the correlation of how the

528
00:16:34,409 --> 00:16:32,739
molecules are interacting if you're

529
00:16:35,669 --> 00:16:34,419
talking about agnostic bio signatures

530
00:16:37,409 --> 00:16:35,679
and you want to build quantitative

531
00:16:39,179 --> 00:16:37,419
frameworks for not only looking for life

532
00:16:40,619 --> 00:16:39,189
on other worlds but quantifiably

533
00:16:42,720 --> 00:16:40,629
predicting what that life might look

534
00:16:44,999 --> 00:16:42,730
like if you have a set of statistical

535
00:16:46,799 --> 00:16:45,009
constraints you can start to think about

536
00:16:47,970 --> 00:16:46,809
building machine learning algorithms for

537
00:16:50,249 --> 00:16:47,980
constructing chemistry's with

538
00:16:52,109 --> 00:16:50,259
alternative chemistry's but the same

539
00:16:53,129 --> 00:16:52,119
sets of constraints and so what we're

540
00:16:54,780 --> 00:16:53,139
really looking for are what are the

541
00:16:56,069 --> 00:16:54,790
statistical regularities across life on

542
00:16:57,720 --> 00:16:56,079
earth and how do we actually quantify

543
00:17:01,650 --> 00:16:57,730
them and then build predictive models

544
00:17:04,019 --> 00:17:01,660
for astrobiology another kind of measure

545
00:17:06,149 --> 00:17:04,029
you might use is to think about

546
00:17:08,220 --> 00:17:06,159
biomolecular chirality now usually we

547
00:17:09,449 --> 00:17:08,230
think about this also as we do with life

548
00:17:11,610 --> 00:17:09,459
as a black or white issue it's either

549
00:17:12,659 --> 00:17:11,620
homo chiral or it's not but if you

550
00:17:14,309 --> 00:17:12,669
actually look at the statistical

551
00:17:16,189 --> 00:17:14,319
patterns in chirality across the

552
00:17:17,939 --> 00:17:16,199
biosphere it's a much more complex story

553
00:17:19,829 --> 00:17:17,949
so it's shown in this network

554
00:17:23,159 --> 00:17:19,839
representation and how do Kim is giving

555
00:17:25,529 --> 00:17:23,169
a talk on this work later today is the

556
00:17:27,179 --> 00:17:25,539
biosphere level Network now looking for

557
00:17:29,519 --> 00:17:27,189
statistical patterns and whether a

558
00:17:30,930 --> 00:17:29,529
molecule is chiral or achiral now if you

559
00:17:31,830 --> 00:17:30,940
have a chiral molecule it's not just

560
00:17:33,690 --> 00:17:31,840
whether it's left-handed or right-handed

561
00:17:35,639 --> 00:17:33,700
but how many chiral centers it has it's

562
00:17:36,930 --> 00:17:35,649
a very complex problem but you can

563
00:17:38,129 --> 00:17:36,940
actually start to look at statistical

564
00:17:40,440 --> 00:17:38,139
regularities and build particular

565
00:17:42,690 --> 00:17:40,450
frameworks for how lot how biology is

566
00:17:44,610 --> 00:17:42,700
actually using chirality to architect

567
00:17:46,549 --> 00:17:44,620
biochemical networks and maybe there

568
00:17:49,080 --> 00:17:46,559
might be some universal rules underlying

569
00:17:50,130 --> 00:17:49,090
and you just speed up so pathway

570
00:17:51,690 --> 00:17:50,140
assembly and thinking about

571
00:17:53,580 --> 00:17:51,700
probabilistic bio signatures has also

572
00:17:55,140 --> 00:17:53,590
been discussed already the only plan I'm

573
00:17:56,790 --> 00:17:55,150
gonna make about this with what Luke

574
00:17:58,410 --> 00:17:56,800
Ronan is doing is that it actually

575
00:18:00,120 --> 00:17:58,420
connects to theoretical frameworks

576
00:18:01,919 --> 00:18:00,130
because not only do you have a way of

577
00:18:03,180 --> 00:18:01,929
fresh holding for biology but you have a

578
00:18:05,730 --> 00:18:03,190
way of thinking about what biology is

579
00:18:07,049 --> 00:18:05,740
doing in chemical space which allows us

580
00:18:08,640 --> 00:18:07,059
to think about building quantitative

581
00:18:11,250 --> 00:18:08,650
theory and predictive frameworks for

582
00:18:12,419 --> 00:18:11,260
other chemistry's you can do the same

583
00:18:14,340 --> 00:18:12,429
thing with thinking about life on other

584
00:18:15,570 --> 00:18:14,350
planets and so this is on Harrison Smith

585
00:18:17,549 --> 00:18:15,580
poster that's gonna be presented later

586
00:18:18,960 --> 00:18:17,559
thinking about how could you actually

587
00:18:22,230 --> 00:18:18,970
predict what biochemistry might look

588
00:18:23,760 --> 00:18:22,240
like on other worlds and it also leads

589
00:18:25,830 --> 00:18:23,770
to statistical characterization of

590
00:18:26,760 --> 00:18:25,840
exoplanet atmospheres and so one of the

591
00:18:28,770 --> 00:18:26,770
things that we've been doing is taking

592
00:18:30,720 --> 00:18:28,780
this idea of taking observational

593
00:18:32,700 --> 00:18:30,730
uncertainties and building statistical

594
00:18:34,620 --> 00:18:32,710
models for how you might think about

595
00:18:36,210 --> 00:18:34,630
what's detectable and what's actually

596
00:18:39,060 --> 00:18:36,220
going to quantify the differences in

597
00:18:40,650 --> 00:18:39,070
plants that are alive or not again using

598
00:18:42,090 --> 00:18:40,660
this kind of network based approach and

599
00:18:43,770 --> 00:18:42,100
I'm just going to make a nod to Tulsa

600
00:18:45,690 --> 00:18:43,780
Fisher's talk later this week about

601
00:18:46,919 --> 00:18:45,700
statistical characterization of jovi and

602
00:18:48,720 --> 00:18:46,929
atmospheres based on the network

603
00:18:50,430 --> 00:18:48,730
structure of the planetary atmosphere

604
00:18:52,740 --> 00:18:50,440
and how you can actually start to think

605
00:18:53,880 --> 00:18:52,750
about system level organizational

606
00:18:55,440 --> 00:18:53,890
planets from a quantitative framework

607
00:18:57,780 --> 00:18:55,450
and talk about quantitatively the

608
00:18:59,220 --> 00:18:57,790
differences so just go back to the

609
00:19:00,810 --> 00:18:59,230
Bayesian framework I think the thing

610
00:19:03,000 --> 00:19:00,820
that's really important for us to start

611
00:19:04,500 --> 00:19:03,010
thinking about is how we're actually

612
00:19:06,480 --> 00:19:04,510
building our approaches together for a

613
00:19:07,830 --> 00:19:06,490
common goal and how we can put this into

614
00:19:09,750 --> 00:19:07,840
quantitative frameworks that are really

615
00:19:11,820 --> 00:19:09,760
going to bring out your biology into the

616
00:19:14,690 --> 00:19:11,830
next decades where we actually can talk

617
00:19:16,890 --> 00:19:14,700
about statistical confidence levels in

618
00:19:18,780 --> 00:19:16,900
what the likelihood of life is in the

619
00:19:19,710 --> 00:19:18,790
universe and with that I'm just going to

620
00:19:26,300 --> 00:19:19,720
thank my group because they're pretty