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Astronomy, OFotU The String Landscape & Multiverse, The Anthropic Principle, and Anselm’s Ontological Argument Dr. Gerald B. Cleaver Wheaton College 26 Mar 2008 500 1010 Outline Intro to String Theory Landscape of String Theory Anthropic Principle Anselm’s Ontological Argument A10a a g abc b Ac . 10 500 500 Physicists seeking Einstein’s final goal the Theory of Everything (Physical) Scientific Understanding of Universe Sought in String (M) Theory A10a a g abc b Ac . 10 500 Science Fiction has become Science Extra Dimensions (7 to be exact) Parallel Universes (at least 1 + maybe a few more) Multiple Universes (perhaps ~ 10100 to 500) Warped Spacetime Time before Time Future for the Universe A10a a g abc b Ac . 10 500 String Theory implies nature of reality & existence is more complex … more beautiful … yet more simple … then ever imagined before! Aa a g abc b Ac . Visible Universe 13.7 billion light years In diameter = 8 x1022 mi trillion galaxies, trillion stars per galaxy All Matter & Forces in the Universe Unified by String Theory Particles & Forces Like Notes on a Violin String B A ♪♫ ♪♫ C D ♪♫ ♪♫ E ♪♫ F G ♪♫ String Interactions consistent w/ Relativity Astronomy, OFotU Quantum Mechanics Requires String Theory w/ 9 + 1 Dimensional Spacetime Astronomy, OFotU Strings have two vibrations – CW & CCW Spin = # of Vibrations in our 3+1 Dim. Spacetime Gravitons = Spin 2 Particles = Strings w/ both vibes in 3+1 Dim S-T Photons, Gluons, W+,-, Z (non-grav. force part.) = Spin 1 Particles = Strings w/ 1 vibe in 3+1 Dim S-T & 1 vibe in 6 Dim Comp Space SUSYMatter = Spin 0 Particles = Strings w/ both vibes in 6 Dim Comp Space 9 Dim 3 Large Dim + 6 Compact Dim Products of 6 Circular Directions Forming Spherical or Too Simple! Toroidal too simple to result in Either the matter particles that exist … Sean Carroll, From the Universe to the Laboratory, http://pancake.uchicago.edu/~carroll So more complex shapes investigated … S. Carroll, http://pancake.uchicago.edu/~carroll Or the force carrying particles … Require Calabi-Yau Compactification Shape from 6 Compactified Dimensions 2 Dim Surface C-Y Surface—Need to extend to 6 Dim jpierre R. Brandenberger Energy Modes R. Brandenberger String Duality R. Brandenberger Finite Initial Size and Temperature of Universe Nagging Problem for 1st Decade (1985-95): Not Just 1 10-Dimensional String Theory But 5! www.sukidog.com/jpierre/strings/ Solution: Duality (Equality) of All 5 String Theories www.sukidog.com/jpierre/strings/ Each ‘Theory” is SAME THEORY IN DIFFERENT MATHEMATICAL LANGUAGE O Й א ڜ www.sukidog.com/jpierre/strings/ www.sukidog.com/jpierre/strings/ Membrane String w/ 10 Dim w/ 11 Dim R. Brandenberger Two 9-brane “Universes”= “Us & Them” and extra dimension between Compactify 6 of the 9 Spatial Directions of each Brane as Before Horava et al. Effective 5-Dimensional Theory Horava et al. Size of 5th Dimension? 10-33 cm < y < 0.1 mm 500 1010 S. Carroll, http://pancake.uchicago.edu/~carroll Tests for sub-mm.directions Fgrav = -Gm1m2/r2 -Gm1m2/r2+n 1/r2 form of gravity being tested. Standard gravity verified down to 0.15 mm at Univ. of Wash. with 97% confidence level Manufacturing of Stringy Blackholes! If sub-mm. dimension then it may be possible to produce gravitons and mini-black holes (with peco-second half-lives) at Fermilab & CERN this decade! Mini-black holes have distinct decays —easily identifiable! Black Holes Detectors for Fermilab and CERN Proposed Explanation for Big Bang Implying Time Before Time! Single Event Astronomy, OFotU Astronomy, OFotU Cyclical Events The colliding Branes would not remain perfectly flat as they approach each other due to quantum effects. Big Bang Inflations occurs in bumps on Branes that collide first. Multiple, separated, Big Bang regions might have been formed from distinct collision points of Branes! Multiple universes on our Brane besides 1+ Parallel Branes along an extra spatial direction 500 1010 S. Carroll, http://pancake.uchicago.edu/~carroll 500 1010 S. Carroll, http://pancake.uchicago.edu/~carroll S. Carroll, http://pancake.uchicago.edu/~carroll 1010 500 S. Carroll, http://pancake.uchicago.edu/~carroll 1010 500 S. Carroll, http://pancake.uchicago.edu/~carroll 1010 500 Present view of universe from Milky Way You are here ↓ Future view of universe from Milky Way, in ~ 1 Trillion Years Milky Way torn up in a few more 100 Billion Years Solar system torn apart in a few more 10 Billion Years New Scientist, 5 Feb 2005 S. Carroll, http://pancake.uchicago.edu/~carroll 1010 500 S. Carroll, http://pancake.uchicago.edu/~carroll 1010 500 S. Carroll, http://pancake.uchicago.edu/~carroll 1010 500 String Landscape C.C. 1 10-120 ~ 10100 to 500 Models in M-Theory String Landscape C.C. 1 10-119 10-120 Anthropic Principle of String Theory 500 1010 Examination of the State of the Universe from Anthropic Principle and Fine Tuning Weak Anthropic Principle (WAP): "The observed values of all physical and cosmological quantities are not equally probable but they take on values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirements that the Universe be old enough for it to have already done so." (Barrow and Tipler 1986: 16). The Merriam-Webster dictionary defines WAP as conditions that are observed in the universe must allow the observer to exist. Strong Anthropic Principle (SAP): "The Universe must have those properties which allow life to develop within it at some stage in its history." (Barrow and Tipler 1986). 500 1010 Barrow and Tipler then proposed three (overlapping) elaborations of the SAP: (i) "There exists one possible Universe 'designed' with the goal of generating and sustaining 'observers.' " This implies that the purpose of the universe is to give rise to intelligent life, with the laws of nature and their fundamental constants set to ensure that life as we know it will emerge and evolve. Fine tuning of constants in nature result as necessities for life. (ii) "Observers are necessary to bring the Universe into being." Barrow and Tipler believe that this can be validly inferred from quantum mechanics. (iii) "An ensemble of other different universes is necessary for the existence of our Universe." This interpretation sympathizes with the many worlds interpretation of quantum mechanics. We will see a possible reemergence of this in string theory 500 1010 Fine-Tuning: The premise of the fine-tuned universe assertion is that any small change in the twenty or so physical constants would make the universe radically different and therefore, unsuitable for life: If, for example, the electron's charge were slightly different, or if the strong nuclear force were only 2% stronger, di-protons would be stable and hydrogen would fuse too easily, making stars as we know them impossible and prevent the universe from developing life as we know it. Or, if the cosmological constant had been greater than it is by a factor of 10, the universe would have expanded to fast for galaxies to ever form. Eternal Inflationary Universe Each later universe has lower cosmological constant than did the universe from which it came. String Cosmology implies physical creation is likely eternal forward. God’s creative act never ceases. Each universe produces an infinitude of universes. A. Linde, Banff, 2004 Understanding of String Landscape and our Universe in relation to it Controversial topic at the moment—numerous papers Domain walls, near-BPS bubbles, and probabilities in the landscape, A. Ceresole et al., hep-th/0605266. On the Geometry of the String Landscape and the Swampland, H. Ooguri and C. Vafa, hep-th/0605264. Cosmological Landscape From Nothing: Some Like It Hot, A. Barvinsky and A. Kamenshchik, hep-th/0605132. The Supersymmetric Vistas of the Supergravity Landscape, T. Ortin, Annalen Phys. 15 (2006) 252. Inflation, dark matter and dark energy in the string Landscape, A. Riddle and L Urena-Lopez, astro-ph/0605205. Eternal observers and bubbler abundances in the Landscape, The Landscape 'avant la lettre'. V. Vanchurin and A. Vilenkin, hep-th/0605015. The Landscape 'avant la lettre‘, Role of Anthropic Principle? Hotly debated in String/M-Theory: e.g., On making predictions in a multiverse: Conundrums, dangers, and coincidences, A. Aguirre, astro-ph/0506519. The Anthropic principle and the duration of the cosmological past, M. Cirkovic, astro-ph/0505005. Supersymmetry breaking in the anthropic landscape, L. Susskind, hep-th/0405189. Is there a string theory landscape: Some cautionary notes, M. Dine, hep-th/0405189. Multiple universes, cosmic coincidences, and other dark matters, A. Aguirre and M. Tegmark, hep-ph/0409072 Is there a string theory landscape? T. Banks et al., hep-th/0309170. Can the universe experience many cycles with different vacua? Y. Piao, hep-ph/0407258. String/M-Theory as presently understood has a large parameter space of variables (angles between each compactified direction, lengths of each, plus things called fluxes and torques) each leading to universes (observable, hidden, or both) with differing properties. On the order of > 10100 different universes all seem equally possible. Why our particular String/M-Theory universe? Some scientists (e.g. Stephen Hawking) are suspicious that determination of a particular choice of ALL of the M-Theory parameters might not be totally determinable, based on Gödel’s Theorem, which says that one cannot formulate a finite system of axioms to prove every result in mathematics. This means that inconsistencies or indeterminacies can arise if one tries to prove statements that refer to themselves. A physical theory is a mathematical model. So if there are mathematical results that cannot be proved, there are physical problems that cannot be solved. We do not live outside of the universe, but instead we and our theories are both part of the universe we are describing. Hence our theories are also self-referring. And thus we might suspect that any Theory of Everything determined by a finite number of known parameters or variables might ultimately be incomplete or undetermined! Multiverse necessitates Augustine’s Block Universe view: God beyond all creation-beyond of all spacetimes. Histories of all spacetimes appear as a moment Multiverse Anselm’s Ontological Argument: God is that than which nothing greater can be conceived. (Proslogion, Chap. 2, c. ~ 1100 A.D.) A10a a g abc b Ac . 10 500 Philosophical and theological issues raised by String/M-Theory and the Multiverse Picture: Immensely expanded concept of (10+1)-dimensional reality and multiple universes has profound implications for meaning of transcendence of God Poses problems to process theology concept of God evolving with and within a universe. The (10+1)-dimensional bulk universe might be compared to St. Augustine’s concept of block universe. 500 1010 String/M-Theory Provides deeper understanding of spacetime and reality Presents our universe with a simplicity, order, and beauty never before imagines. Simultaneously provides for complexity of the (multi/uni)-verse Suggests more to our universe than ever before imagined. Has implications for theological views of God regarding meaning of transcendence—expanded view of Augustine’s block universe. 500 1010 Interesting String (Cosmology) Web Sites (also image sources): http://www.superstringtheory.com/ John Schwarz’ "The Official String Theory Web Site" http://www.sukidog.com/jpierre/strings/ String Tutorial with glossary, refs & links http://www.superstring-theory.com/EnglishVersion.html another excellent intro http://www.superstringtheory.com/cosmo/index.html http://www.ba.infn.it/~gasperin/ http://feynman.princeton.edu/~steinh/ Great string cosmology sites http://www.nuclecu.unam.mx/%7Ealberto/physics/string.html http://dmoz.org/Science/Physics/Quantum_Mechanics/ http://pages.wooster.edu/bboroson/clinks.html worthwhile collections of links to other major string sites ** http://pancake.uchicago.edu/~carroll ** Several slides in the presentation borrowed from this site!