Podcasts about supergravity

Peter Woit is a theoretical physicist and mathematician, currently a Senior Lecturer in the Department of Mathematics at Columbia University. Peter is known for his work in quantum field theory and representation theory, particularly for contributions to the understanding of gauge theories. In addition to his academic work, Woit is the author of "Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law," where he critically examines string theory while advocating for alternative approaches in the quest for a unified physical theory. Become a YouTube Member Here: https://www.youtube.com/channel/UCdWIQh9DGG6uhJk8eyIFl1w/join Patreon: https://patreon.com/curtjaimungal (early access to ad-free audio episodes!) Join TOEmail at https://www.curtjaimungal.org Links: ⁠- Peter Woit's first appearance on TOE: https://www.youtube.com/watch?v=9z3JYb_g2Qs - ⁠Peter Woit's book on Quantum Theory and Representations: https://www.amazon.com/Quantum-Theory-Groups-Representations-Introduction/dp/3319646109 - Peter Woit's Papers - https://inspirehep.net/literature?sort=mostrecent&size=25&page=1&q=a%20P.Woit.1 - Peter Woit's Blog - https://www.math.columbia.edu/~woit/wordpress/ - Peter Woit's book “Not Even Wrong”: https://amzn.to/3X8c1pS Timestamps: 00:00 - Introduction 01:31 - Overview of Unification in Physics and the Standard Model 05:11 - Historical Development of the Standard Model and its Success 07:00 - Introduction to General Relativity and its Challenges 09:32 - Unanswered Questions in the Standard Model (SU1, SU2, SU3) 13:12 - Technical Issues in Quantum Field Theory and General Relativity 17:24 - The Rise of Grand Unified Theories (GUTs) 21:07 - Challenges and Failures of GUTs (Proton Decay) 25:43 - Abandonment of GUTs and Introduction of Supersymmetry 26:45 - Basics of Supersymmetry and Its Predictions 31:28 - Failure of Supersymmetry (No Evidence for Superpartners) 32:08 - Supergravity, Kaluza-Klein Theories, and Extra Dimensions 35:52 - String Theory and the Unification Paradigm in the 1980s 39:00 - Experimental Failures and the Lack of Evidence for String Theory 41:00 - Ongoing Pursuit of Failed Theories and Resistance to New Ideas 47:09 - The Shift in Attitudes Towards Unification Efforts in Physics 48:13 - Introduction to Peter Woit's New Ideas on Unification 52:32 - The Role of Four-Dimensional Geometry and Spinors in Unification 58:11 - Wick Rotation and Differences Between Euclidean and Minkowski Space-Time 1:03:05 - Technical Challenges in Wick Rotation and Quantum Field Theory 1:09:01 - Unique Aspects of Spinors in Euclidean vs. Minkowski Space-Time 1:14:38 - The Dirac Operator and its Role in Space-Time Symmetry 1:18:02 - Relation to Supersymmetry and the Right-Handed Nature of Space-Time 1:22:04 - Connection to Gravity and Loop Quantum Gravity (Ashtakar Variables) 1:23:04 - Outro / Support TOE Support TOE: - Patreon: https://patreon.com/curtjaimungal (early access to ad-free audio episodes!) - Crypto: https://tinyurl.com/cryptoTOE - PayPal: https://tinyurl.com/paypalTOE - TOE Merch: https://tinyurl.com/TOEmerch Follow TOE: - NEW Get my 'Top 10 TOEs' PDF + Weekly Personal Updates: https://www.curtjaimungal.org - Instagram: https://www.instagram.com/theoriesofeverythingpod - TikTok: https://www.tiktok.com/@theoriesofeverything_ - Twitter: https://twitter.com/TOEwithCurt - Discord Invite: https://discord.com/invite/kBcnfNVwqs - iTunes: https://podcasts.apple.com/ca/podcast/better-left-unsaid-with-curt-jaimungal/id1521758802 - Pandora: https://pdora.co/33b9lfP - Spotify: https://open.spotify.com/show/4gL14b92xAErofYQA7bU4e - Subreddit r/TheoriesOfEverything: https://reddit.com/r/theoriesofeverything Join this channel to get access to perks: https://www.youtube.com/channel/UCdWIQh9DGG6uhJk8eyIFl1w/join #science #physics #stringtheory Learn more about your ad choices. Visit megaphone.fm/adchoices

I will describe the four-derivative corrections to four-dimensional N=2 minimal gauged supergravity and show that they are controlled by two constants. Interestingly, the solutions of the equations of motion in the two-derivative theory are not modified by the higher-derivative corrections. I will use this to arrive at a general formula for the regularized on-shell action for any asymptotically locally AdS_4 solution of the theory and show how the higher-derivative corrections affect black hole thermodynamic quantities in a universal way. I will employ these results in the context of holography to derive new explicit results for the subleading corrections in the large N expansion of supersymmetric partition functions on various compact manifolds for a large class of three-dimensional SCFTs arising from M2- and M5-branes. I will also briefly discuss possible extensions and generalizations of these results.

SAT TECHNOLOGY trains your mind to initiate your thoughts from the level of UNIFIED field and get the desired fulfilled

In this talk I will describe the light-front formulation of maxi- mally supersymmetric theories. This is a formalism where only the physical degrees of freedom is used. This means that the SuperPoincaré invariance is non-linearly realized, a fact we use to build the models. In this formalism the N=4 Yang-Mills and the N=8 Supergravity are treated in a very similar fashion and the close relationship between them is obvious. I will also show that the exceptional symmetry E_7(7) is very naturally connec- ted to the N=8 SuperPoincaré algebra. This formalism is an al- ternative to the ordinary covariant formalisms and is very use- ful to investigate the UV properties of these models.

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Strings and Fundamental Physics 2014

Strings and Fundamental Physics 2014

Strings and Fundamental Physics 2014

Strings and Fundamental Physics 2014

WiTThai ตอนนี้ฟีเจอริ่งผลงานวิจัยสาขาฟิสิกส์ทฤษฏีของ ดร. ปริญญา การดำริห์ ภาควิชาฟิสิกส์ คณะวิทยาศาสตร์ จุฬาลงกรณ์มหาวิทยาลัย อาจวรงค์ ป๋องแป๋ง จันทมาศ หนึ่งในผู้ดำเนินรายการ ได้เป็นตัวแทนไปสัมภาษณ์ ดร. ปริญญา จากนั้นนำเรื่องราวกลับมาเล่าถ่ายทอดให้ผู้ดำเนินรายการอีกสองท่านได้ฟังและซักถาม เนื้อหาของตอนเน้นปูพื้นฐานความเข้าใจทฤษฎีฟิสิกส์ต่างๆ (อาธิ string theory, standard model, supersymmetry, general relativity, supergravity) และความพยายามประสานทฤษฎีเชิงควอนตัมซึ่งใช้กับอนุภาคเล็กๆ เข้ากับทฤษฎีแรงโน้มถ่วงซึ่งใช้กับโลกระดับใหญ่ คุณอาจวรงค์ได้อธิบายเรื่องที่เข้าใจยากมากๆ เหล่านี้ ให้คนทั่วไปพอจะสามารถเข้าถึงหรืออย่างน้อยๆ ร่วมเห็นความสำคัญได้ เช่นได้ร่วมเข้าใจว่าเหตุใดความก้าวหน้าด้านการคำนวณที่อาจารย์ปริญญาทำสำเร็จจึงได้รับการยอมรับในระดับโลก นอกจากนี้ท้ายตอนมีเสียงบันทึกของอาจารย์ปริญญาเองมาให้ข้อคิดเกี่ยวกับความอดทนและไม่ย่อท้อต่ออุปสรรคในการทำงาน รายการตอนนี้ช่วยเพิ่มความหลากหลายให้ผู้ฟังรับทราบว่านอกจากงานเชิงประยุกต์แล้ว สกว.ก็สนับสนุนงานวิจัยเชิงทฤษฎีที่พยายามจะเข้าใจธรรมชาติในระดับลึกเช่นเดียวกัน   Timestamp 0:00-4:52 intro 4:52-7:32 เกริ่นถึงดร.ปริญญา 7:33-10:23 ปูอารมณ์ อะไรบันดาลใจให้ป๋องแป๋งชอบฟิสิกส์ทฤษฎี 10:24-13:25 หัวข้องานวิจัยของดร.ปริญญา ที่ว่าด้วย supergravity และความสัมพันธ์แบบ AdS/CFT ใน 7 มิติ 13:43-16:47 ย้อนไปเล่าความพยายามรวมกฏเกณฑ์ของโลกเล็กเข้ากับโลกใหญ่ 16:47- 20:23 Paul Dirac จับทฤษฎีสัมพัทธภาพพิเศษมารวมกับควอนตัม ได้เป็นสนามควอนตัม และนำไปสู่ Standard Model ซึ่งเวิร์กมาก 20:23-22:36 ลองเอาสัมพัทธภาพทั่วไปที่กว้างกว่ารวมดูบ้าง ปรากฏเจอค่าอนันต์เบร้อ คำนวณไม่ได้ 22:36-23:54 หันไปพึ่งทฤษฎี Superstring 23:54-25:23 เล่าโยงไปถึง Supergravity เกิดจากสัมพัทธภาพทั่วไป ผสม supersymmetry ซึ่งคำนวณไม่ได้เบร้ออยู่นานจนนึกว่าไม่มีประโยชน์ 25:23-31:44 กลับมาซูเปอร์สตริง ปกติเวิร์กมากสำหรับพลังงานต่ำ ข้อจำกัดคือเวลาชนพลังงานสูงคำนวณไม่ได้ แต่พอเอามาใส่ในกรอบ Supergravity แล้วดันคำนวณได้ ทฤษฎีนี้เลยคืนชีพ 31:44-36:00 ย้อนกลับไปอธิบาย Supersymmetry ที่เป็นส่วนผสมของ Supergravity เริ่มจากสมมาตรคืออะไร 36:00-43:34 Emmy Noether เอาเรื่องสมมาตรมาอธิบายที่มาของกฏฟิสิกส์ได้ 43:34-45:47 แตะนิดๆ เรื่อง gauge theory 45:47-54:13 อธิบายเรื่อง supersymmetry บรรดาอนุภาคที่ควรจะมีคู่สมมาตรของกันและกัน 54:13-56:13 ประโยชน์ของ Supersymmetry เอามากำจัดค่าอนันต์ได้ 56:13-1:01:14 ทวนนิดหน่อย ต่อด้วยหลักการย้ายกรอบคำนวณจากทฤษฎีนึงไปอีกทฤษฎีนึง ซึ่งก็คือความสัมพันธ์แบบ AdS/CFT  ทำให้ทฤษฎีพวกอนุภาคเอาไปคำนวณกับทฤษฎีแรงโน้มถ่วงได้ 1:01:14-1:04:39 หลัก holographic principle คือเปลี่ยนจำนวนมิติแล้วคำนวณได้ แรงโน้มถ่วงใน d มิติ ย้ายไปคำนวณเป็นสนามควอนตัม d-1 มิติได้ 1:04:39-1:12:39 ในที่สุดก็มาถึงงานวิจัยของอาจารย์ปริญญา ที่ทำเรื่อง supergravity ใน 7 มิติ ซึ่งไม่มีใครทำได้มาก่อน / 1:12:39-1:18:23 ปิดท้ายรายการด้วยเสียงดร.ปริญญา เล่าเรื่องความพยายามในการแก้โจทย์ปัญหา 1:18:23-1:24:33  เฉลยคำถาม WiTThai ตอนที่แล้ว ประกาศรางวัล และถามคำถามตอนใหม่   ตอนนี้ฟีเจอริ่งผลงานวิจัยสาขาฟิสิกส์ทฤษฏีของ ดร. ปริญญา การดำริห์ ภาควิชาฟิสิกส์ คณะวิทยาศาสตร์ จุฬาลงกรณ์มหาวิทยาลัย ตัวอย่างรายชื่องานวิจัยที่ตีพิมพ์ลง Journal of High Energy Physics (JHEP) 3D supergravity from wrapped M5-branes - Parinya Karndumri, Eoin Ó Colgáin - March 2016 Non-semisimple gauging of a magical N = 4 supergravity in three dimensions -Parinya Karndumri - December 2015 Twisted compactification of N = 2 5D SCFTs to three and two dimensions from F(4) gauged supergravity -Parinya Karndumri - September 2015 Erratum to: Holographic RG flows in six dimensional F(4) gauged supergravity - Parinya Karndumri-June 2015 RG flows from (1,0) 6D SCFTs to N = 1 SCFTs in four and three dimensions - Parinya Karndumri-June 2015 ป๋องแป๋งไปสัมภาษณ์อาจารย์แล้วนำกลับมาเล่าถ่ายทอดอีกที รูปคุณ Emmy Noether รูปตารางอนุภาค Supersymettry ตัวอย่างสมการที่เกี่ยวข้องกับเรื่อง supergravity https://www.facebook.com/witcastthailand/photos/a.384378794958298.93979.380263635369814/1116763781719792/?type=3&permPage=1

Mon, 12 Oct 2015 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/18768/ https://edoc.ub.uni-muenchen.de/18768/1/Betz_Andre_W.pdf Betz, André Wolfgang ddc:530, ddc:500, Fakultät für Physik 0

In this paper, we construct non-trivial solutions to the 2D-dimensional field equations of Double Field Theory (DFT) by using a consistent Scherk-Schwarz ansatz. The ansatz identifies 2(D - d) internal directions with a twist U-N(M) which is directly connected to the covariant fluxes F-ABC. It exhibits 2(D - d) linear independent generalized Killing vectors K-I (J) and gives rise to a gauged supergravity in d dimensions. We analyze the covariant fluxes and the corresponding gauged supergravity with a Minkowski vacuum. We calculate fluctuations around such vacua and show how they gives rise to massive scalars field and vectors field with a non-abelian gauge algebra. Because DFT is a background independent theory, these fields should directly correspond the string excitations in the corresponding background. For (D − d) = 3 we perform a complete scan of all allowed covariant fluxes and find two different kinds of backgrounds: the single and the double elliptic case. The later is not T-dual to a geometric background and cannot be transformed to a geometric setting by a field redefinition either. While this background fulfills the strong constraint, it is still consistent with the Killing vectors depending on the coordinates and the winding coordinates, thereby giving a non-geometric patching. This background can therefore not be described in Supergravity or Generalized Geometry.

Dall'agata, G (Università degli Studi di Padova) Wednesday 30 May 2012, 10:15-11:00

Papadopoulos, G (King's College London) Thursday 31 May 2012, 10:15-11:00

Dall’Agata, G (Università degli Studi di Padova) Friday 29 June 2012, 14:00-14:35

Andrei Linde. Inflation in supergravity and string theory

Hermann Nicolai. Consistent Kaluza Klein universes from maximal supergravity

Renata Kallosh. N=8 supergravity

Strickland-Constable, C (Imperial) Thursday 16 February 2012, 15:00-15:45

Park, J-H (Sogang University) Thursday 16 February 2012, 11:30-12:15

Waldram, D (Imperial College London) Wednesday 11 January 2012, 14:00-15:00

In the first part of this thesis, we study classes of hybrid and chaotic inflation models in four-dimensional N=1 supergravity. Therein, the eta-problem can be resolved relying on fundamental symmetries in the Kaehler potential. Concretely, we investigate explicit realizations of superpotentials, in which the flatness of the inflaton potential is protected at tree level by a shift symmetry or a Heisenberg symmetry in the Kaehler potential. In the latter case, the associated modulus field can be stabilized during inflation by supergravity effects. In the context of hybrid inflation, a novel class of models, to which we refer as "tribrid inflation," turns out to be particularly compatible with such symmetry solutions to the eta-problem. Radiative corrections due to operators in the superpotential, which break the respective symmetry, generate the required small slope of the inflaton potential. Additional effective operators in the Kaehler potential can reduce the predicted spectral index so that it agrees with latest observational data. Within a model of chaotic inflation in supergravity with a quadratic potential, we apply the Heisenberg symmetry to allow for viable inflation with super-Planckian field values, while the associated modulus is stabilized. We show that radiative corrections are negligible in this context. In the second part, the tribrid inflation models are extended to realize gauge non-singlet inflation. This is applied to the matter sector of supersymmetric Grand Unified Theories based on the Pati-Salam gauge group. For the specific scenario in which the right-handed sneutrino is the inflaton, we study the scalar potential in a D-flat valley. We show that despite potentially dangerous two-loop corrections, the required flatness of the potential can be maintained. The reason for this is the strong suppression of gauge interactions of the inflaton field due to its symmetry breaking vacuum expectation value. In addition, the production of stable magnetic monopoles at the end of the stage of inflation can be avoided. Finally, we sketch how in tribrid inflation models the concepts discussed in the two parts can be combined to realize inflation via Heisenberg symmetry in local supersymmetric SO(10) grand unification.

D. Gross/KITP/UCSB Perspectives [ Fri ] Click to play Flash 8 player:

L. Randall/Harvard Black Holes & Quantum Gravity at the LHC [ Fri ] Click to play iFrame/Flash player:

Extremal black holes in theories of gravity coupled to abelian gauge fields and neutral scalars, such as those arising in the low-energy description of compactifications of string theory on Calabi-Yau manifolds, exhibit the attractor phenomenon: on the event horizon the scalars settle to values determined by the charges carried by the black hole and independent of the values at infinity. It is so, because on the horizon the energy contained in vector fields acts as an effective potential (the black hole potential), driving the scalars towards its minima. For spherically symmetric black holes in theories where gauge potentials appear in the Lagrangian solely through field strengths, the attractor phenomenon can be alternatively described by a variational principle based on the so-called entropy function, defined as the Legendre transform with respect to electric fields of the Lagrangian density integrated over the horizon. Stationarity conditions for the entropy function then take the form of attractor equations relating the horizon values of the scalars to the black hole charges, while the stationary value itself yields the entropy of the black hole. In this study we examine the relationship between the entropy function and the black hole potential in four-dimensional N=2 supergravity and demonstrate that in the absence of higher-order corrections to the Lagrangian these two notions are equivalent. We also exemplify their practical application by finding a supersymmetric and a non-supersymmetric solution to the attractor equations for a conifold prepotential. Exploiting a connection between four- and five-dimensional black holes we then extend the definition of the entropy function to a class of rotating black holes in five-dimensional N=2 supergravity with cubic prepotentials, to which the original formulation did not apply because of broken spherical symmetry and explicit dependence of the Lagrangian on the gauge potentials in the Chern-Simons term. We also display two types of solutions to the respective attractor equations. The link between four- and five-dimensional black holes allows us further to derive five-dimensional first-order differential flow equations governing the profile of the fields from infinity to the horizon and construct non-supersymmetric solutions in four dimensions by dimensional reduction. Finally, four-dimensional extremal black holes in N=2 supergravity can be also viewed as certain two-dimensional string compactifications with fluxes. Motivated by this fact the recently proposed entropic principle postulates as a probability measure on the space of these string compactifications the exponentiated entropy of the corresponding black holes. Invoking the conifold example we find that the entropic principle would favor compactifications that result in infrared-free gauge theories.

DEMO (Flash video-player: "STRINGS '07", Tue talks)Click on "GUIDE".."EPISODES" to see list of STRINGS '07/Tue videosWitten, Becker, Douglas, kachru, Zarembo, Beisert, Riccioni, Ooguri, EmparanSee above (1st post) for explanation/analysis

DEMO (Flash video-player: STRINGS '07, Mon talks)Click on "GUIDE".."EPISODES" to see list of STRINGS '07/Mon videosRolandi, Maldacena, Petrini, Trigiante, Sen, Trivedi, Uranga, Blumenhagen, SchellekensSee above (1st post) for explanation/analysis

DEMO (Flash video-player: "STRINGS '07", Fri talks)Click on "GUIDE".."EPISODES" to see list of STRINGS '07/Fri videosPolchinski, Silverstein, Kallosh, Sugimoto, Berkovitz, Bern, Russo, Quevedo, Randall, GrossThe daily "STRINGS '07" talks can be *distributed* to any website, via a compact Flash video player. I.e., "TV channel syndication" over other (related) physics websites during the conference. Increased exposure/reach for STRINGS '07.Enhancement of the current video Content/Distribution model (single distribution point at STRINGS '07 website, downloadable video). iPod/iTunes is an additional distribution point, with unlimited potential:1) iPods (mass-market media-player, 100 million & counting)Science research-tool & public-outreach. Carrying "science videos in your pocket" has a viral-marketing effect.2) AppleTV (living room set-top-box)watching Science videos from comfort of your living room, Science research-tool or public-outreach3) iPhone (debut on June 29, cellphone demographic is >> media-player demographic)same as iPod, but possibly even greater reach/effectDuke & Stanford are "on the curve", & already using 1) for teaching.See sidebar [ "STRINGS "07" TV show player ] on right.

DEMO (Flash video-player: "STRINGS '07", Thu talks)Click on "GUIDE".."EPISODES" to see list of STRINGS '07/Thu videosWiedeman, Mateos, Vafa, Moore, Klemm, Zwiebach, Papdopoulos, Seiberg, Kovtun, ReySee above (1st post) for explanation/analysis

DEMO (Flash video-player: "STRINGS '07", Wed talks)Click on "GUIDE".."EPISODES" to see list of STRINGS '07/Wed videosLinde, Bousso, Verde, Strominger, De BoerSee above (1st post) for explanation/analysis

Ed Witten (IAS/Princeton), 3-D Gravity Revisited [ Tue 9:30am ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

M. Becker (Texas A&M) Runaway in the Landscape [ Tue 10:00am ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:Watch the Video

M. Douglas (Rutgers & IHES) Exploring the Kähler potential [ Tue 11:00 am ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

S. Kachru (Stanford) Comments on Anti-branes [ Tue 11:30 am ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

K. Zarembo (Uppsala) Worldsheet scattering in AdS(5)xS(5) [ Tue 12:00 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

N. Beisert (MPI, Potsdam) Strong/Weak Interpolation in the Spectrum of AdS/CFT [ Tue 3:00 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

F. Riccioni (King's College) E11 and M-theory [ Tue 3:30 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

H. Ooguri (Caltech) On the ubiquity of meta-stable vacua [ Tue 4:30 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

R. Emparan (U.A. Barcelona) Phases of higher-dimensional black holes [ Tue 5:00 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

M. Petrini (LPTHE) Generalised N=1 vacua: geometry and non-geometry [ Mon 11:30 am ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

A. Sen [Harish-Chandra Res.Inst.] Marginal Stability and N=4 Dyon Spectrum [Mon 3:00 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

M. Trigiante [Politecnico, Torino] Mirror-covariant formulation of N=2 supergravity from generalized Calabi-Yau compactifications [ Mon 12:00 pm ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

J. Maldacena (IAS/Princeton) Super Yang Mills scattering amplitudes at strong coupling [ Mon 11:00 am ] Click To Play [ NOTE: quickstart=off, please wait for entire file (~40mb) to load, before it plays ]SlidesFlash 8 version:

This dissertation is devoted to the investigation of the interplay of supersymmetric Yang-Mills theories (SYM) and supergravity (SUGRA). The topic is studied from two points of view: Firstly from the point of view of AdS/CFT correspondence, which realises the coupling of four dimensional superconformal N=4 SYM theory and ten dimensional type IIB SUGRA in a holographic way. In order to arrive at theories that resemble quantum chromodynamics (QCD) more closely, fundamental fields are introduced using probe D7-branes and non-trivial background configuration are considered. In particular supergravity solutions that are only asymptotically anti-de Sitter and break supersymmetry are used. This allows the description of spontaneous chiral symmetry breaking. The meson spectrum is calculated and the existence of an associated Goldstone mode is demonstrated. Moreover it is shown that highly radially excited mesons are not degenerate. Additionally instanton configurations on the D7-branes are investigated, which lead to a holographic description of the dual field theory's Higgs branch. Finally a holographic description of heavy-light mesons is developed, which are mesons consisting of quarks with a large mass difference, such that a treatment of B mesons can be achieved. The second approach to the topic of this thesis is the technique of so-called space-time dependent couplings ("local couplings"), where coupling constants are promoted to external sources. This allows to explore the conformal anomaly of quantum field theories coupled to a classical gravity background. The technique is extended to the superfield description of N=1 supergravity, a complete basis for the anomaly is given and the consistency conditions that arise from a cohomological treatment are calculated. Possible implications for an extension of Zamolodchikov's c-theorem to four dimensional supersymmetric quantum field theories are discussed.

A search for associated chargino neutralino pair production is performed in the trilepton decay channel qq -> chi^+-_1 + chi^0_2 -> l+- + nu + chi^0_1 + mu^+- + mu^+- chi^0_1, using data collected with the D0 detector at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. The data sample corresponds to an integrated luminosity of ~300 pb^-1. A dedicated event selection is applied to all samples including the data sample and the Monte Carlo simulated samples for the Standard Model background and the Supersymmetry signal. Events with two muons plus an additional isolated track, replacing the requirement of a third charged lepton in the event, are analyzed. Additionally, selected events must have a large amount of missing transverse energy due to the neutrino and the two LSP. After all selection cuts are applied, 2 data events are found, with an expected number of background events of 1.75 +- 0.34(stat.) +- 0.46 (syst.). No evidence for Supersymmetry is found and limits on the production cross-section times leptonic branching fraction are set. When the presented analysis is considered in combination with three other decay channels, no evidence for Supersymmetry is found. Limits on the production cross-section times leptonic branching fraction are set. A lower chargino mass limit of 117 GeV at 95% CL is then derived for the mSUGRA model in a region of parameter space with enhanced leptonic branching fractions.