Quantum Scalar Field on Fuzzy de Sitter Space I. Field Modes and Vacua
Abstract: We study a scalar field on a noncommutative model of spacetime, the fuzzy de Sitter space, which is based on the algebra of the de Sitter group $SO(1,d)$ and its unitary irreducible representations. We solve the Klein-Gordon equation in $d=2,4$ and show, using a specific choice of coordinates and operator ordering, that all commutative field modes can be promoted to solutions of the fuzzy Klein-Gordon equation. To explore completeness of this set of modes, we specify a Hilbert space representation and study the matrix elements (integral kernels) of a scalar field: in this way the complete set of solutions of the fuzzy Klein-Gordon equation is found. The space of noncommutative solutions has more degrees of freedom than the commutative one, whenever spacetime dimension is $d>2$. In four dimensions, the new non-geometric, internal modes are parametrised by $S2\times W$, where $W$ is a discrete matrix space. Our results pave the way to analysis of quantum field theory on the fuzzy de~Sitter space.
- X. Chen “Primordial Non-Gaussianities from Inflation Models”, Adv. Astron. 2010 (2010), 638979, arXiv:1002.1416 [astro-ph.CO].
- C. Cheung, P. Creminelli, A. L. Fitzpatrick, J. Kaplan and L. Senatore “The Effective Field Theory of Inflation”, JHEP 03 (2008), 014, arXiv:0709.0293 [hep-th].
- D. Baumann, D. Green, A. Joyce, E. Pajer, G. L. Pimentel, C. Sleight and M. Taronna, “Snowmass White Paper: The Cosmological Bootstrap”, arXiv:2203.08121 [hep-th].
- C. S. Chu, B. R. Greene and G. Shiu, “Remarks on inflation and noncommutative geometry”, Mod. Phys. Lett. A 16 (2001), 2231-2240, arXiv:hep-th/0011241 [hep-th].
- F. Lizzi, G. Mangano, G. Miele and M. Peloso, “Cosmological perturbations and short distance physics from noncommutative geometry”, JHEP 06 (2002), 049, arXiv:hep-th/0203099 [hep-th].
- S. Alexander, R. Brandenberger and J. Magueijo, “Noncommutative inflation”, Phys. Rev. D 67 (2003), 081301, arXiv:hep-th/0108190 [hep-th].
- H. Garcia-Compean, O. Obregon and C. Ramirez, “Noncommutative quantum cosmology”, Phys. Rev. Lett. 88 (2002), 161301, arXiv:hep-th/0107250 [hep-th].
- G. D. Barbosa and N. Pinto-Neto, “Noncommutative geometry and cosmology”, Phys. Rev. D 70 (2004), 103512, arXiv:hep-th/0407111 [hep-th].
- A. Chaney, L. Lu and A. Stern, “Matrix Model Approach to Cosmology”, Phys. Rev. D 93 (2016) no.6, 064074, arXiv:1511.06816 [hep-th].
- J. L. Karczmarek and H. C. Steinacker, “Cosmic time evolution and propagator from a Yang–Mills matrix model”, J. Phys. A 56 (2023) no.17, 175401, arXiv:2207.00399 [hep-th].
- S. Brahma, R. Brandenberger and S. Laliberte, “Emergent cosmology from matrix theory”, JHEP 03 (2022), 067, arXiv:2107.11512 [hep-th].
- M. Marcolli, “Noncommutative Cosmology”, World Scientific (2018).
- M. Buric, D. Latas and L. Nenadovic “Fuzzy de Sitter Space”, Eur. Phys. J. C 78 (2018), 953, arXiv:1709.05158 [hep-th].
- J. Madore, “An introduction to noncommutative differential geometry and its physical applications”, Lond. Math. Soc. Lect. Note Ser. 257 (2000).
- M. Hogervorst, J. Penedones and K. S. Vaziri, “Towards the non-perturbative cosmological bootstrap”, JHEP 02 (2023), 162, arXiv:2107.13871 [hep-th].
- L. Di Pietro, V. Gorbenko and S. Komatsu, “Analyticity and unitarity for cosmological correlators”, JHEP 03 (2022), 023, arXiv:2108.01695 [hep-th].
- B. Brkic, M. Buric and D. Latas, “Laplacian on fuzzy de Sitter space”, Class. Quant. Grav. 39 (2022) no.11, 115001, arXiv:2111.07391 [hep-th].
- M. Buric and J. Madore, “Noncommutative de Sitter and FRW spaces”, Eur. Phys. J. C 75 (2015), 502, arXiv:1508.06058 [hep-th].
- M. Buric and D. Latas, Dusko, “Discrete fuzzy de Sitter cosmology”, Phys. Rev. D 100 (2019), 024053, arXiv:1903.08378 [hep-th].
- S. Cho, “Quantum Mechanics on the h-deformed Quantum Plane”, J. Phys. A, 32 (1999), 2091-2102, arXiv:math-ph/9804015.
- J. Madore and H. Steinacker, “Propagator on the h-deformed Lobachevsky plane”, J. Phys. A 33 (2000), 327-342. arXiv:math/9907023 [math.QA].
- A. A. Kirillov, “Elements of the Theory of Representations”, Springer-Verlag (1976).
- C. Sleight and M. Taronna, “Bootstrapping Inflationary Correlators in Mellin Space”, JHEP 02 (2020), 098, arXiv:1907.01143 [hep-th].
- V. K. Dobrev, G. Mack, V. B. Petkova, S. G. Petrova and I. T. Todorov, “Harmonic Analysis on the n-Dimensional Lorentz Group and Its Application to Conformal Quantum Field Theory”, Lect. Notes Phys. 63, 1 (1977).
- N. D. Birrell and P. C. W. Davies, “Quantum Fields in Curved Space”, Cambridge Univ. Press (1984).
- R. M. Wald, “Quantum Field Theory in Curved Space-Time and Black Hole Thermodynamics”, University of Chicago Press (1995).
- B. Allen, “Vacuum States in de Sitter Space”, Phys. Rev. D 32 (1985), 3136.
- N. A. Chernikov and E. A. Tagirov, “Quantum theory of scalar fields in de Sitter space-time”, Ann. Inst. H. Poincare Phys. Theor. A 9 (1968).
- M. Abramowitz and I. A. Stegun, “Handbook of Mathematical Functions”, Dover, New York (1964).
- D. Jurman and H. Steinacker, “2D fuzzy Anti-de Sitter space from matrix models”, JHEP 01 (2014), 100, arXiv:1309.1598 [hep-th].
- A. Pinzul and A. Stern, “Exact solutions for scalars and spinors on quantized Euclidean AdS2 space and the correspondence principle”, Phys. Rev. D 104 (2021) no.12, 126034, arXiv:2106.13376 [hep-th].
- I. Buric and M. Buric, “The fuzzy BTZ”, JHEP 12 (2022), 102, arXiv:2204.03673 [hep-th].
- J. Madore, “The fuzzy sphere”, Class. Quant. Grav. 9 (1992), 69-88.
- B. Brkic, M. Buric and D. Latas, “Fuzzy de Sitter and anti-de Sitter spaces”, PoS CORFU2021 (2022), 274.
- P. Kravchuk and D. Simmons-Duffin, “Light-ray operators in conformal field theory”, JHEP 11 (2018), 102, arXiv:1805.00098 [hep-th].
- V. Bargmann, “Irreducible unitary representations of The Lorentz group”, Annals Math. 48 568-640 (1947).
- J. D. Bjorken and S. D. Drell, “Relativistic quantum mechanics”, McGraw-Hill, New York (1964).
- M. S. Costa, J. Penedones, D. Poland and S. Rychkov, “Spinning Conformal Blocks”, JHEP 11 (2011), 154, arXiv:1109.6321 [hep-th].
- D. Karateev, P. Kravchuk and D. Simmons-Duffin, “Weight Shifting Operators and Conformal Blocks”, JHEP 02 (2018), 081, arXiv:1706.07813 [hep-th].
- I. Buric and V. Schomerus, “Universal spinning Casimir equations and their solutions”, JHEP 03 (2023), 133, arXiv:2211.14340 [hep-th].
- A. M. Perelomov, “Generalized coherent states and their applications”, Springer-Verlag Berlin Heidelberg (1986).
- G. N. Watson, “A Treatise on the Theory of Bessel Functions”, Cambridge University Press (1922).
- H. Bateman, A. Erdélyi et. al., “Higher Transcendental Functions”, vol 1, McGraw Hill, New York (1953).
Paper Prompts
Sign up for free to create and run prompts on this paper using GPT-5.
Top Community Prompts
Collections
Sign up for free to add this paper to one or more collections.