Fysik // Physics

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Utforskar och använder fysik för att förstå världen och bidrar med tillämpningar, nya material och innovationer som möter dagens behov och framtidens utmaningar.
Stimulerade av vår tids behov och utmaningar är institutionens ambition att främja en kreativ miljö för forskning, lärande och samverkan. Vi tillför en konkurrensfördel genom att länka de bästa internationella forskarna i materialvetenskap, nanoteknologi och energiforskning med ledande industriella partners.

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Explores and uses physics to understand the world, and provide applications, new materials and innovations that meet today's needs, and the challenges of the future.
Stimulated by major needs and challenges in society and industry, our ambition is to foster a creative environment for academic research, learning, innovations and utilisation. We provide a competitive advantage by linking top-level international and interdisciplinary academic performance in the areas of material science, nanotechnology, life science engineering and energy research with world-leading industrial R&D&I projects.

Studying at the Department of Physics at Chalmers

For research and research output, please visit https://research.chalmers.se/en/organization/physics/

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Adsorbate induced core level shifts of transition metal surfaces
(2013) Nilsson, Viktor; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
A shift in the core electron binding energy detected with X-ray photoelectron spec- troscopy (XPS) gives insight into the local chemical configuration of atoms. Such infor- mation can be used, for instance, to determine the surface structure upon adsorption. By comparing the experimental spectra with theoretical predictions, the core level shifts can be attributed to specific atomic configurations. In this thesis, core level shifts for metal surfaces upon adsorption have been computed by electronic structure calculations within density functional theory (DFT), using the software VASP. The transition metals Ni, Cu, Ru, Rh, Pd, Ag, Cd, Pt and Au have been investigated in terms of their surface structure and adsorption sites for CO, H, O and S have been tested. Core level shifts for the hcp(0001)/fcc(111) and fcc(100) facets have been deter- mined for each adsorbate. Since the involved mechanisms contributing to these energy shifts are difficult to decouple, trends among shifts as well as a model for explaining them have been sought. A clear dependence on coordination number is seen, where the binding energy is lower for a lower coordination. Trends depending on element are also found. The shift upon adsorption is towards higher binding energies for almost all elements and adsorbates. Notable exceptions are Ag and Cd. The correlation between d-band centre shift and core level shift is confirmed whereas the common model of viewing charge transfer as a dominant effect for the shifts is found insufficient.
Analys av rörelsemönster för kvinnliga innebandyspelare Framtagning av en metod för kvantitativa undersökningar
(2015) Hannonsson, Simon; Olsson, Alexander; Gotby Westlund, Lovisa; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
Sammandrag Detta kandidatarbete har haft som mål att, genom biomekanisk modellering, ta fram en metod som tillåter analys av kvinnliga innebandyspelares rörelsemönster under en rörelsesekvens karaktäristisk för sporten. Sekvensen som har analyseras är en kort löpsekvens med en vändning på 180 grader. Data som beskriver rörelsen och markreaktionskrafter i samband med vändningen har samlats in med hjälp av kamerasystemet Qualisys Motion Capture med tillhörande kraftplattor. Denna data har sedan behandlats i progamvaran Qualisys Track Manager för att efter det kunna exporteras till beräkningsprogrammet Matlab. Genom ingejörsmässiga beräkningar och antaganden har sedan en metod tagits fram som kan identifiera kvantitativa skillnader mellan olika spelare och därmed ge indikationer på vad en effektiv rörelse är. Detta har gjorts genom ett program som är kodat i Matlab. Programmet läser in insamlad data och beräknar utifrån denna relevanta vinklar, hastigheter, accelerationer och krafter som representerar kinematiken och den inversa dynamiken för rörelsen. Mätningar har gjorts på tre olika spelare då de utför den valda rörelsesekvensen. Alla viktiga resultat som beräknats från mätdatan presenteras numeriskt i tabell samt visualiseras i grafer; de olika spelarnas vändningar är således kvantitativt jämförbara.
Black Holes and Hidden Symmetries - Solution Generating Techniques with Dimensional Reduction and Group Theory
(2014) Widmark, Axel; Aronsson, Marcus; Dahlberg, Axel; Roos, Erik; Hesslow, Linnea; Romare, Elin; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
In this bachelor thesis we have studied a technique of generating solutions for the curvature of black holes. In order to understand the underlying theory of this method we have studied the fundamentals of general relativity and group theory. The technique utilizes dimensional reduction to expose hidden symmetries of black holes, which enables us to find new solutions. This type of solution-generating technique is currently subject to heavy research, with hope of exposing deeper symmetries of spacetime and black holes.
Feasibility of FPGA-based Computations of Transition Densities in Quantum Many-Body Systems
(2013) Anderzén, Robert; Rahm, Magnus; Salberger, Olof; Strandberg, Joakim; Svedung Wettervik, Benjamin; Wårdh, Jonatan; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
This thesis presents the results from a feasibility study of implementing calculations of transition densities for quantum many-body systems on FPGA hardware. Transition densities are of interest in the field of nuclear physics as a tool when calculating expectation values for different operators. Specifically, this report focuses on transition densities for bound states of neutrons. A computational approach is studied, in which FPGAs are used to identify valid connections for one-body operators. Other computational steps are performed on a CPU. Three different algorithms that find connections are presented. These are implemented on an FPGA and evaluated with respect to hardware cost and performance. The performance is also compared to that of an existing CPU-based code, Trdens. The FPGA used to implement the proposed designs was a Xilinx Virtex 6, built into Maxeler’s MAX3 card. It was concluded that the FPGA was able to find the connections of a one-body operator in a fraction of the time used by Trdens, ran on a single CPUcore. However, the CPU-based conversion of the connections to the form in which Trdens presents them, was much more time-consuming. For FPGAs to be feasible, it is hence necessary to accelerate the CPU-based computations or include them into the FPGA-implementations. Therefore, we recommend further investigations regarding calculations of the final representation of transition densities on FPGAs, without the use of an off-FPGA computation.
Higgsbosonen, standardmodellen och LHC
(2013) Nilsson, Anton; Norberg, Olof; Nordgren, Linus; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
This report aims to provide an insight into the particle physics of today, and into the research that goes on within the field. The focus is partly on the recent discovery of the Higgs boson, and partly on how software can be used to simulate processes in particle accelerators. Basic concepts of particle physics and the search for the Higgs boson are discussed, and experimental results, including those from the Large Hadron Collider, are compared with simulations made in MadGraph 5. Furthermore, simple new models of particle physics are created in FeynRules, in order to make simulations based on the models. To support the presentations of these aspects, some of the underlying theory is built from the ground up. Additionally, instructions are given on the usage of the programs FeynRules, for creation of models; MadGraph 5, for simulating processes in particle accelerators; and MadAnalysis 5, for data processing of the results obtained. The most significant results are simulations of processes commonly used for Higgs boson searches, with results in qualitative agreement with predictions and experimental data. The results also include consistent analytical and numerical calculations in a simple model with one particle.
Jacobi-Davidson Algorithm for Locating Resonances in a Few-Body Tunneling System
(2014) Hjelmare, Gustav; Larsson, Jonathan; Lidberg, David; Östnell, Sebastian; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
A recent theoretical study of quantum few-body tunneling implemented a model using a Berggren basis expansion. This approach leads to eigenvalue problems, involving large, complex-symmetric Hamiltonian matrices. In addition, the eigenspectrum consists mainly of irrelevant scattering states. The physical resonance is usually hidden somewhere in the continuum of these scattering states, making diagonalization difficult. This thesis describes the theory of the Jacobi-Davidson algorithm for calculating complex eigenvalues and thus identifying the resonance energies of interest. The underlying Davidson method is described and combined with Jacobi's orthogonal complement method to form the Jacobi-Davidson algorithm. The algorithm is implemented and applied to matrices from the theoretical study. Furthermore, a non-hermitian formulation of quantum mechanics is introduced and the Berggren basis expansion explained. The results show that the ability of the Jacobi-Davidson algorithm to locate a specific interior eigenvalue greatly reduces the computational times compared to previous diagonalization methods. However, the additional computational cost of implementing the Jacobi correction turns out to be unnecessary in this application; thus, the Davidson algorithm is sufficient for finding the resonance state of these matrices.
Kanonisk Cox-representation och EM-skattningsalgoritmer för triangulära fastypsmodeller
(2014) Andersson, Simon; Holmer, Erik; Isacson, Oscar; Schmidt, John; Reibring, Julia; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
Katalysmaterial för en effektivare vattenklyvning -att möjliggöra lagring av förnyelsebar energi
(2016) Yudanov, Marina; Westman, Kasper; Ögren, Linus; Palm, Caroline; Chalmers tekniska högskola / Institutionen för fysik (Chalmers); Chalmers University of Technology / Department of Physics (Chalmers)
This work presents a broad study of the catalytic activity of possible metal oxide cata- lysts for the oxygen evolution reaction (OER) in the electrolysis of water. Experiments are conducted in a three-electrode cell with 0,1 M KOH base electrolyte in order to rank the following metal oxides according to their catalytic ability for this reaction: IrO2, PtO2, ITO, Fe2O3, TiO2, FTO, SnO2, HfO2, Nb2O5, all of which are on an ITO-on-glass substrate. FTO on glass is also tested, as well as Fe2O3 on an FTO-on-glass substrate. Indicators for catalytic ability are taken to be overpotential and exchange current den- sity. Parallell, in-depth studies of the literature lead to suggestions as to which surface properties and material parameters are important in this process. The practical and the- oretical approaches are then combined as the following possible relevant parameters are related to the performance of the metal oxides as catalysts: binding energy of OH to the catalytic surface, total number of d electrons, number of valence d electrons, enthalpy of formation of the next oxidation state, and the number of so-called outer electrons. Relationships are set up with the aim of identifying which parameters best predict ca- talytic activity. Of these parameters, called descriptors for the OER, binding energy of OH to the catalyst surface as calculated by computational physics methods appears the most successful. In an attempt to grasp these methods, which are the prevalent form of research in the field, they are applied for a surface of PtO2. A relaxation of this surface as well as its binding energy for O is presented, which according to the literature scales linearly to the binding energy for OH. In order to tie this work to technological advan- ces in society and to renewable energy systems where hydrogen can be used either to store energy or to create biofuels such as methane, calculations are made for the actual efficiency of hydrogen production of the most economically sound catalyst identified in this work. IrO2 was identified as the best catalyst for the OER, and Nb2O5 as the worst. This was confirmed by the best descriptor for catalytic ability which was shown to be binding energy between catalyst surface and intermediate OH. Other descriptors were at best moderately predictive, or too complex to be included in a study on this level. The performance of a catalyst for the OER is shown to be critical for the economical viability of an industrial hydrogen production based on electrolysis.
LHC, the Higgs particle and physics beyond the Standard Models - Simulation of an additional scalar particle a's decay
(2014) Djärv, Tor; Olsson, Andreas; Salér-Ramberg, Justin; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
This thesis explores a possible addition of a scalar boson to the Standard Model. Apart from a quadratic coupling to the Higgs boson, it couples to the photon and the gluon. To fully be able to explore this new boson, it is necessary to get acquainted with some of the vast background theory in form of quantum field theory. This involves the most fundamental ideas of relativistic quantum mechanics, the Lagrangian formulation, cross section, decay rate, calculations of scatteringamplitude, Feynman diagrams, the Feynman rules and the Higgs mechanism. To analyse the particle, it was necessary to use computer aid in form of FeynRules, a package to Mathematica, for retrieve the Feynman rules for the particle, and MadGraph 5 for numerical calculations of decay rate and cross section. This was used to find limits to coupling constants with in the Lagrangian to concur with experimental findings.
Lokalitet, fullständighet och Bells olikhet. Undersökningar av kvantmekanikens grundvalar.
(2011) Andreas, Andersson; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
Vissa aspekter av kvantmekanikens grundvalar undersöks – särskilt lokalitet, fullständighet,separerbarhet och kausalitet – och hur dessa är relaterade till realism. Därigenom klargörs ett par av problemen kring hur teorin skall förstås och förklaras. Några ramar fastläggs, som varje tolkning av kvantmekaniken måste hålla sig inom; dessa utgör premisser som en kvantfysikfilosofi skall bygga på. En analys görs av Bohms version av Einstein, Podolsky och Rosens argument om att kvantmekaniken är ofullständig. Idén att utöka kvantmekaniken med dolda variabler diskuteras. Därefter härleds Bells olikhet i olika versioner; dessa är banbrytande resultat inom studiet av kvantmekanikens grundvalar, i och med att de anger ett kvantitativa, empiriskt prövbara villkor, som varje lokal dolda variabler-teori måste uppfylla. Vissa förutsägelser som kan göras ur kvantmekaniken bryter mot detta villkor. Härur kan Bells teorem deduceras; det säger att ingen lokal dolda variabler-teori har samma statistiska förutsägelser som kvantmekaniken. En översikt över experimentella undersökningar som utförts visar att naturen bryter mot Bells olikhet, vilket talar för kvantmekaniken. Under antagandet att kvantmekaniken är fullständig följer att det råder en underlig icke-lokalitet i det fysikaliska universum.
Lokalitet, fullständighet och Bells olikhet: Undersökningar av kvantmekanikens grundvalar
(2011) Andreasson, Andreas; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
Undersökningar av kvantmekanikens grundvalar – särskilt lokalitet, fullständighet,separerbarhet och kausalitet – och hur dessa är relaterade till realism.Därigenom klargörs ett par av problemen kring hur teorin skall förstås och förklaras. Några ramar fastläggs, som varje tolkning av kvantmekaniken måste hålla sig inom; dessa utgör premisser som en kvantfysikfilosofi skall bygga på. En analys görs av Bohms version av Einstein, Podolsky och Rosens argument om att kvantmekaniken är ofullständig. Idén att utöka kvantmekaniken med dolda variabler diskuteras. Därefter härleds Bells olikhet i olika versioner; dessa är banbrytande resultat inom studiet av kvantmekanikens grundvalar, i och med att de anger ett kvantitativa, empiriskt prövbara villkor, som varje lokal dolda variabler-teori måste uppfylla. Vissa förutsägelser som kan göras ur kvantmekaniken bryter mot detta villkor. Härur kan Bells teorem deduceras; det säger att ingen lokal dolda variabler-teori har samma statistiska förutsägelser som kvantmekaniken. En översikt över experimentella undersökningar som utförts visar att naturen bryter mot Bells olikhet, vilket talar för kvantmekaniken. Under antagandet att kvantmekaniken är fullständig följer att det råder en underlig icke-lokalitet i det fysikaliska universum.
Monte-Carlo Simulations of Nuclear Reactions at Relativistic Energies
(2013) Rathsman, Torbjörn; Buller, Stefan; Magnusson, Joel; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
Nanoferromagnets in the focus of plasmon nanoantennas
(2014) Ghirardini, Lavinia; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
Plasmonics is the field of science that studies light-matter interaction. Collective oscillations of electrons at the surface of metals, resulting from an electromagnetic excitation, are responsible for plasmonic phenomena. In metallic nanostructures, these oscillations confine and enhance an electromagnetic field at a sub-wavelength scale, thus having a huge impact on enhanced sensing and spectroscopy applications. Moreover, plasmonics has been also used to enhance weak magneto-optical (MO) effects in magnetic materials. Magneto-optical phenomena are interactions between a magnetic field in a medium and an electromagnetic wave propagating through it [1], resulting in a rotation of the polarization plane and a change in the ellipticity of the polarization state. Magneto-optically active materials have nowadays found applications in a variety of contexts, such as magnetization imaging [2], telecommunication [3], sensors and data storage [4]. Current research focuses on the development of materials with large MO activity to improve the performance of these devices and expand their applications. Since an important factor in integrated technology is size, scaling the dimensions of MO components while preserving the readability of their signal is a crucial requirement. Since the MO response of a material is related to the optical field inside it, plasmonics can allow for its control and manipulation. The interplay between plasmons and magneto-optically active elements has been an important research topic in the field of magnetoplasmonics [5, 6]. Driven by such a research trend, fast, reliable and sensitive MO characterization tools are required in magnetoplasmonics. Conventional systems like the MOKE optical setup, based on frequency modulation methods, are expensive and rather time consuming [7]. This is especially cumbersome in the investigation of small signals which require, in addition, long detector integration time. Here we develope a simple, fast, sensitive and broadband spectrometer-based plasmonic and MO characterization tool. With this tool, which allows small MO signal detection from nanostructures in ambient conditions [8], we study hybrid Au-Fe magnetoplasmonic nanoantennas with different compositions. Evolution of the MO signal when changing the relative amount of the two materials is assessed. We study the extinction spectra and MO response of both the pure Au and hybrid Au-Fe magnetoplasmonic systems. The trend studied is also compared to that of continuous Fe reference films. Our aim is to assess whether these hybrid structures, combined with the use of our detection scheme, are suitable to provide the reduction of the size of the magneto-optical active material without losing the ability to read MO signal from these nanostructures.
Oscillationer i centrala nervsystemet - Hjärnaktivitet vid Parkinsons sjukdom
(2014) Roos, Filip de; Olander, Erik; Persdotter, Amanda; Lokrantz, Anna; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
Syftet med projektet är att, genom simulering,reproducera oscillationer i avfyrningsfrekvensen omkring 80 Hz för neuroner i hjärnan hos parkinsonssjuka råttor som behandlats med Levodopa.[1] Med hjälp av ett programpaket, Brian, speciellt framtaget för att simulera neuronnätverk simuleras inhiberande och exciterande leakyintegrate-and-fire-neuroner med synapsdynamik som beskrivs av fördröjning, stigtid och falltid. Flera av rapportens resultat visar oscillationer i avfyrningsfrekvens vid 80 Hz för olika parameterkombinationer. Korrelation mellan neuroner och avfyrningsfrekvens för neuronnätverket visar att nätverkets avfyrning är periodisk och sparse. Slutsatsen är att olika faktorer som påverkar nätverkets oscillation är beroende av varandra, vilket gör det svårt att analysera systemet.
Quantum Resonances in a Complex-Momentum Basis
(2013) Bengtsson, Jonathan; Granström, Pontus; Embréus, Ola; Ericsson, Vincent; Wireklint, Nils; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
Resonances are important features of open quantum systems. We study, in particular, unbound and loosely bound nuclear systems. We model 5He and 6He in a few-body picture, consisting of an alpha-particle core with one and two valence neutrons respectively. Basis-expansion theory is briefly explained and then used to expand the nuclear system in the harmonic oscillator and momentum bases. We extend the momentum basis into the complex plane, obtaining solutions that form a Berggren basis. With the complex-momentum method we are able to reproduce experimentally observed resonances in 5He. The 5He Berggren basis solutions are used as a single-particle basis to create many-body states in which we expand the 6He system. For the two-body interaction between the neutrons, we use two different phenomenological models: a Gaussian and a Surface Delta Interaction (SDI). The strength of each interaction is fitted to reproduce the 6He ground state energy. With the Gaussian interaction we do not obtain the 6He resonance, whereas with the SDI we do. The relevant parts of the second quantization formalism is summarized, and we briefly discuss a possible implementation.
Runaway electrons in tokamak disruptions in the presence of impurities
(2014) Capone, Luigino; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
Disruptions in tokamak devices are phenomena where the plasma loses its confinement suddenly, on time scales of a few milliseconds, releasing most part of the plasma energy onto the machine components. These phenomena are dangerous to the plasma-facing components and they pose a severe threat to the machine's integrity, causing the deposition of intense thermal uxes on the first wall materials and serious electromagnetic stresses on the structure. High-energy runaway electrons are also generated due to disruptive phenomena, causing further damage to the machine. The recent successful installation of the JET ITER-like wall (ILW) in place of the previous carbon-based wall, suggests an assessment of the impact of different wall composition on the runaway production. Extracting experimental data from two different plasma discharges equipped respectively with beryllium and carbon wall, the production of runaway electrons has been investigated through a numerical code. Simulations for the evolution of runaway electrons have been carried out for different scenarios, considering both a prescribed exponential temperature decay and disruptions triggered by an argon injection scenario. Argon and carbon/ beryllium impurities coming from the sputtering of the first wall has also been included in a further scenario. A comparison of two different discharges in terms of generation mechanisms for runaways has also been performed, together with various scans for different argon concentrations. Simulations showed that impurities coming from different walls, have a different impact on the produced runaway currents and on generation mechanisms.
Simulation of Charged Particle Orbits in Fusion Plasmas
(2015) Hoppe, Mathias; Iantchenko, Aylwin; Strandberg, Ingrid; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
When designing a fusion device, knowledge of the particle motion inside the fusion plasma is crucial. The charged plasma particles are confined inside the device using a strong magnetic field, which influences particle motion. Particle trajectories can therefore be obtained by numerically solving the equations of motion for a charged particle in the confining magnetic field. With the simulation tool developed as a part of this project, charged particle orbits are studied. Especially, the properties of the so called banana and passing orbit topologies are studied and the observed results explained using theoretical models. We find expressions that approximately describe the width of the banana and passing orbits and the location of the banana orbit’s mirror points. The orbit dependence on mass, charge and energy is investigated and an expression for the particle’s deviation from a field line is derived. Also, the cause for banana orbits forming is studied and their occurrence is shown to depend on how the particle’s velocity vector is directed. Finally, the two computational methods used, where either the particle or its guiding-center is followed, are compared with respect to both energy conservation and computational time. The guiding-center approach is shown to greatly reduce computational cost.
Simulering av Oorts moln och nära planeter
(2014) Strömbeck, Frida; Bore, Alexander; Rizk, Charbel; Ekdahl, Calle; Chalmers tekniska högskola / Institutionen för teknisk fysik; Chalmers University of Technology / Department of Applied Physics
Abstract To examine the influence of different surroundings on cometary orbits we used computer simulations. They showed that there are at least two different sources for the comets that make up the Oort cloud. They also showed that the galactic tide and star passages can send comets of the Oort cloud into the solar system. Comets inside the solar system were also simulated, to determine whether or not Jupiter could catch them, and also to examine which way to preferably avert a comet on a collision course towards Earth.
Terahertz Generation in Laser-Induced Gas-Plasmas
(2018) Edwardsson, Per; Hallborn, Hanna; Strandberg, Erik; Chalmers tekniska högskola / Institutionen för fysik (Chalmers); Chalmers University of Technology / Department of Physics (Chalmers)
In this thesis the THz generation mechanism for a two-color laser pulse induced gas plasma is investigated. A fluid model for the laser-plasma interaction is presented and discussed. The model is discretised and implemented in a computational code, and the scheme is tested and compared to published results of a similar model. The simulations are used to show the impact of different parameters of the laserplasma interaction on THz generation. The different trends that are found are then discussed and compared to the theory of THz generation. Keywords: Plasma, Terahertz, Laser, Laser-Plasma-Interaction, Simulation, Maxwell, Partial Differential Equations.
Uncertainty Quantifications in Chiral Effective Field Theory
(2014) Fahlin Strömberg, Dag; Lindby, Mattias; Lilja, Oskar; Mattsson, Björn; Chalmers tekniska högskola / Institutionen för fundamental fysik; Chalmers University of Technology / Department of Fundamental Physics
The nuclear force is a residual interaction between bound states of quarks and gluons. The most fundamental description of the underlying strong interaction is given by quantum chromodynamics (QCD)that becomes nonperturbative at low energies. A description of low-energy nuclear physics from QCD is currently not feasible. Instead, one can employ the inherent separation of scales between low- and high-energy phenomena, and construct a chiral effective field theory (EFT). The chiral EFT contains unknown coupling coefficients, that absorb unresolved short-distance physics, and that can be constrained by a non-linear least-square fitting of theoretical observables to data from scattering experiments. In this thesis the uncertainties of the coupling coefficients are calculated from the Hessian of the goodness-of-fit measure X2. The Hessian is computed by implementing automatic differentiation (AD)in an already existing computer model, with the help of the Rapsodia AD tool. Only neutron-proton interactions are investigated, and the chiral EFT is studied for leading-order (LO) and next-to-leadingorder (NLO). In addition, the correlations between the coupling coefficients are calculated, and the statistical uncertainties are propagated to the ground state energy of the deuteron. At LO, the relative uncertainties of the coupling coefficients are 0.01%, whereas most of the corresponding uncertainties at NLO are 1%. For the deuteron, the relative uncertainties in the binding energies are 0.2% and 0.5% for LO and NLO, respectively. Moreover, there seems to be no obvious obstacles that prevent the extension of this method to include the proton-proton interaction as well as higher chiral orders of the chiral EFT, e.g. NNLO. Finally, the propagation of uncertainties to heavier many-body systems is a possible further application.

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