Fast Fourier Transform Telescope

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Fast Fourier Transform Telescope is Tegmark and Zaldarriaga's name for a design for an all-digital synthetic-aperture telescope. It is a type of interferometer designed to be cheaper than standard telescope interferometers currently in use.

In 1868, Hippolyte Fizeau realized that the lenses and mirrors in a telescope perform a physical approximation of a Fourier transform.[citation needed] He noted that by using an array of small instruments it would be possible to measure the diameter of a star with the same precision as a single telescope which was as large as the whole array — a technique which later became known as astronomical interferometry. See History of astronomical interferometry.

In a 2008 paper, Tegmark and Zaldarriaga proposed a telescope design[1] that dispenses altogether with the lenses and mirrors, relying instead on computers fast enough to perform all the necessary transforms. The concept is an all-digital telescope with an antenna consisting of a rectangular grid. Building radio telescopes this way should become feasible within a few years if Moore's law continues to hold. Eventually optical telescopes could also be built this way.[2] This technique is already being used in radar applications.

This paper refers to an earlier telescope design from 1993 which took direct images of the Crab nebula at radio wavelengths using an eight-by-eight-pixel two-dimensional spatial FFT processor.[3]

See also[edit]


Further reading[edit]

  • Jan Hamann, Steen Hannestad, Martin S. Sloth, Yvonne Y. Y. Wong (2008), "Observing trans-Planckian ripples in the primordial power spectrum with future large scale structure probes", Journal of Cosmology and Astroparticle Physics, arxiv 0807.4528
  • Jonathan R. Pritchard, Elena Pierpaoli (2008), "Constraining massive neutrinos using cosmological 21 cm observations", Phys. Rev. D 78:065009,2008, arxiv 0805.1920
  • Yi Mao, Max Tegmark, Matthew McQuinn, Matias Zaldarriaga, Oliver Zahn (2008), "How accurately can 21 cm tomography constrain cosmology?", Phys. Rev. D 78, 023529 (2008), arxiv 0802.1710
  • Kendrick M. Smith, Asantha Cooray, Sudeep Das, Olivier Doré, Duncan Hanson, Chris Hirata, Manoj Kaplinghat, Brian Keating, Marilena LoVerde, Nathan Miller, Graça Rocha, Meir Shimon, Oliver Zahn (2008), "CMBPol Mission Concept Study: Gravitational Lensing", arxiv 0811.3916
  • Eli Visbal, Abraham Loeb, Stuart Wyithe (2008 preprint), "Cosmological Constraints from 21 cm Surveys After Reionization", arxiv 0812.0419
  • Vernon Barger, Yu Gao, Yi Mao, Danny Marfatia, (2008 preprint), "Inflationary Potential from 21 cm Tomography and Planck", arxiv 0810.3337
  • Y Mao (2008 preprint), "Constraining Gravitational and Cosmological Parameters with Astrophysical Data", arxiv 0808.2063