254:(ASU). In 2013, Walker became an assistant professor at the School of Earth and Space Exploration as well as the Beyond Center for Fundamental Concepts in Science at ASU. She became a faculty member for the Center for Social Dynamics and Complexity, as well as a graduate faculty member for the Department of Physics and Complex Systems Initiative at ASU in 2014. In 2015, Walker began a fellowship at the ASU-SFI Center for Biosocial Complex Systems as part of a joint educational and research program between
270:. She seeks to develop new theories of physics to explain what life is, how it emerged, and what signs of life might look like on other planets. She uses mathematical models to investigate chemical evolution and the development of networks on Prebiotic Earth. She looks at information flow in biotic and abiotic systems to further define life and its
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discovered that only networks with long polymers show potential to produce significant spontaneous asymmetrical chirality in speculative early Earth conditions. Walker and her colleagues, have also shown that the violent environment of prebiotic Earth would have continuously changed the chirality of
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suggested that major evolutionary transitions, such as the origin of life, could be characterized by a reverse of information flow in a system from bottom-up to top-down. They also determined that living systems have a separation of data from machinery, and non-trivial replication. Walker has shown
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Walker is a member of multiple scientific organizations, including the Blue Marble Space
Institute of Science, the NASA Astrobiology Institute, the Foundational Questions Institute (FQXI), and the International Society for Artificial Life, serving on its board of directors. She is also a member of
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also revealed that homochiral proto-domains can form in the middle of racemic networks, and that the slowdown of these networks through processes such as tidal motion or evaporating pools could have led to the stabilization of these structures on early Earth. The results of these simulations have
334:, and has participated in many interviews, panels, and lectures to discuss her research and topics related to her fields of study. She has had press coverage in dozens of news sources, and been active on multiple media platforms. She appeared on the Discover Channel's
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One of the major challenges in studying the origin of life has been the inability to clearly define what life is. In her investigations, Walker has used the flow of information in systems as a means to distinguish life from non-life. She used the
317:, and other models to discern feasible universal traits for life. It was shown that in biological systems the components are subordinate to the whole, in what is called top-down causation. Furthermore, a logistical model of Walker
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reaction networks by a mechanism they termed punctuated chirality. This suggests that the origin of homochirality was not a singular event, and that chiral selection occurred at the same time as the origin of life. Walker and
399:, M.A. Grover and N. V. Hud. (2012) Universal Sequence Replication, Reversible Polymerization and Early Functional Biopolymers: A Model for the Initiation of Prebiotic Sequence Evolution. PLoS ONE 7: e34166.
192:, and on the board of directors for Blue Marble Space, a nonprofit education and science organization. As a science communicator, she is a frequent guest on podcasts and series, such as
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the
Complex Systems Society and is on the board of directors for Blue Marble Space. She is a member of the LifeBoat Foundation and serves on its Astrobiology/SETI Advisory Board.
290:, and the activation-polymerization-epimerization-depolymerization (APED) model to imitate potential prebiotic conditions for autocatalytic polymerization networks. Walker
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188:(ASU), associate director of the ASU-SFI Center for Biosocial Complex Systems and an associate professor at ASU. She is a co-founder of the astrobiology social network
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Gleiser, Marcelo; Walker, Sara Imari (2008-05-09). "An
Extended Model for the Evolution of Prebiotic Homochirality: A Bottom-Up Approach to the Origin of Life".
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393:(2008) An Extended Model for the Evolution of Prebiotic Homochirality: A Bottom-Up Approach to the Origins of Life. Orig. Life Evol. Biosph. 38: 293 – 315.
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Walker has won multiple awards for her teaching, writing, lectures, and contributions to her community. She had been awarded several fellowships:
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286:, which is a key problem in the origin of life. In her research she has used several models such as the Sandars polymerization model, the
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theoretically how the occurrence of these biotic traits in an abiotic system present a possible framework for the origin of life.
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working at the NSF/NASA Center for
Chemical Evolution. In 2011 she accepted a NASA Postdoctoral Program Fellowship with the
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Walker, Sara Imari; Cisneros, Luis; Davies, Paul C. W. (2012-07-19). "Evolutionary
Transitions and Top-Down Causation".
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418:, H. Kim and P.C.W. Davies (2016) The Informational Architecture of the Cell. Phil. Trans. Roy. Soc. A 374 20150057.
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Fellow, ASU-SFI Center for
Biosocial Complex Systems, Arizona State University and Santa Fe Institute 2015 – 2018
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helped to reveal what possibly occurred during the origin of homochiralty, and its effect on the origin of life.
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in the episode "Are We Here for a Reason?". She has made two appearances on
National Public Radio's
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808:; Walker, Sara Imari (2009-04-16). "Toward Homochiral Protocells in Noncatalytic Peptide Systems".
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Gleiser, Marcelo; Thorarinson, Joel; Walker, Sara Imari (2008-10-08). "Punctuated
Chirality".
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and P.C.W. Davies “The
Algorithmic Origins of Life” (2013) J. Roy. Soc. Interface 6: 20120869.
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earning a B.S. in physics in 2005. She earned her Ph.D. in physics and astronomy in 2010 from
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Sara Walker: Physics of Life, Time, Complexity, and Aliens | Lex
Fridman Podcast #433
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Walker is a theoretical physicist and astrobiologist with research interests in the
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After graduating from Dartmouth, Walker began a postdoctoral fellowship at the
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New Hampshire Space Grant/NASA Graduate Fellowship, NH Space Grant 2007 – 2008
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19:"Sara Walker" redirects here. For a different spelling of the name, see
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NASA Postdoctoral Program Fellowship, NASA Astrobiology Institute 2011
1187:"Meet the 'Dune' Readers: Kim Stanley Robinson and Sara Imari Walker"
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412:(2008) Punctuated Chirality. Orig. Life Evol. Biosph. 38: 499 – 508.
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Fourth Prize, Foundational Questions Institute Essay Contest 2012.
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Theoretical Models for the Emergence of Biomolecular Homochirality
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Theoretical Models for the Emergence of Biomolecular Homochirality
1252:"List of International Society for Artificial Life Board Members"
274:. Some of the highlights of her work in this field so far are:
1003:(2016-03-13). "The informational architecture of the cell".
617:"Recent PhD Graduates | Department of Physics and Astronomy"
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Walker has studied the possible mechanisms of the origin of
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346:. She is a co-founder of the astrobiology social network
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Gordon F. Hull Fellowship, Dartmouth College 2009 – 2010
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Life as No One Knows It: The Physics of Life's Emergence
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Essay Contest 2015 for her essay The Descent of Math.
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1006:Philosophical Transactions of the Royal Society A
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940:Origins of Life and Evolution of Biospheres
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1124:Proceedings of Artificial Life XIII () P
337:Through the Wormhole with Morgan Freeman
195:Through the Wormhole with Morgan Freeman
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332:communication of science to the public
304:Information flow in biological systems
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352:I'm a Scientist: Get Me Out of Here!
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999:Walker, Sara Imari; Kim, Hyunju;
743:"The algorithmic origins of life"
1367:21st-century American physicists
1362:Arizona State University faculty
1185:Minoff, Annie (August 5, 2014).
433:Foundational Questions Institute
408:M. Gleiser, J. Thorarinson, and
1332:American theoretical physicists
1154:10.7551/978-0-262-31050-5-ch038
244:Georgia Institute of Technology
216:Florida Institute of Technology
168:with research interests in the
88:Georgia Institute of Technology
52:Florida Institute of Technology
1372:Researchers of artificial life
1209:calciumj11.imascientist.org.uk
1093:10.1088/0034-4885/79/10/102601
1072:Reports on Progress in Physics
330:Walker is an advocate for the
258:and Arizona State University.
206:Walker was born and raised in
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230:and her doctoral advisor was
670:"Beyond prebiotic chemistry"
132:Other academic advisors
1342:Scientists from Connecticut
278:The origin of homochirality
248:NASA Astrobiology Institute
92:NASA Astrobiology Institute
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1228:Lex Fridman (2024-06-13).
365:interviewed her about it.
212:Cape Cod Community College
56:Cape Cod Community College
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1302:"FQXi Essay Contest 2012"
1277:"FQXi Essay Contest 2015"
970:10.1007/s11084-008-9134-5
906:10.1007/s11084-008-9147-0
842:10.1007/s11084-009-9166-5
150:http://emergence.asu.edu/
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1357:Dartmouth College alumni
1205:"Profile – Calcium Zone"
252:Arizona State University
202:Education and background
186:Arizona State University
100:Arizona State University
699:10.1126/science.aaf6310
535:"Sara Walker | iSearch"
1037:10.1098/rsta.2015.0057
771:10.1098/rsif.2012.0869
218:, where she graduated
621:physics.dartmouth.edu
378:Selected publications
250:and began working at
162:theoretical physicist
1240:– via YouTube.
737:Walker, Sara Imari;
1146:2012arXiv1207.4808I
1085:2016RPPh...79j2601D
1029:2016RSPTA.37450057W
962:2008OLEB...38..293G
898:2008OLEB...38..499G
834:2009OLEB...39..479G
691:2016Sci...352.1174C
685:(6290): 1174–1175.
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214:and studied at the
176:, physics of life,
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1013:(2063): 20150057.
1001:Davies, Paul C. W.
739:Davies, Paul C. W.
485:Sara Imari Walker
315:information theory
256:Santa Fe Institute
96:Santa Fe Institute
481:"saraimariwalker"
423:Awards and honors
326:Public engagement
288:Langevin equation
226:. Her thesis was
224:Dartmouth College
158:Sara Imari Walker
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1130:: 283–290.
416:S.I. Walker
410:S.I. Walker
403:S.I. Walker
397:S.I. Walker
391:S.I. Walker
384:S.I. Walker
363:Lex Fridman
208:Connecticut
136:Paul Davies
78:abiogenesis
36:Nationality
30:Sara Walker
1326:Categories
1237:2024-06-14
1214:2016-11-15
1020:1507.03877
651:2016-11-15
627:2016-11-15
602:2016-11-15
575:2016-11-15
544:2016-11-15
517:2016-11-06
490:2016-11-06
455:References
1137:1207.4808
953:0802.2884
889:0802.1446
825:0810.5398
762:1207.4803
715:206649123
357:Her book
272:emergence
220:cum laude
178:emergence
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1101:27608530
1045:26857675
986:18929297
978:18465201
914:18841492
858:14040409
850:19370399
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707:27257242
262:Research
39:American
1311:10 July
1286:10 July
1142:Bibcode
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1081:Bibcode
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830:Bibcode
780:3565706
687:Bibcode
678:Science
593:"Media"
348:SAGANet
313:model,
297:Gleiser
190:SAGANet
146:Website
1261:22 May
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