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- Van_Cittert–Zernike_theorem abstract "The Van Cittert–Zernike theorem, named after physicists Pieter Hendrik van Cittert and Frits Zernike, is a formula in coherence theory that states that under certain conditions the Fourier transform of the mutual coherence function of a distant, incoherent source is equal to its complex visibility. This implies that the wavefront from an incoherent source will appear mostly coherent at large distances. Intuitively, this can be understood by considering the wavefronts created by two incoherent sources. If we measure the wavefront immediately in front of one of the sources, our measurement will be dominated by the nearby source. If we make the same measurement far from the sources, our measurement will no longer be dominated by a single source; both sources will contribute almost equally to the wavefront at large distances.This reasoning can be easily visualized by dropping two stones in the center of a calm pond. Near the center of the pond, the disturbance created by the two stones will be very complicated. As the disturbance propagates towards the edge of the pond, however, the waves will smooth out and will appear to be nearly circular.The van Cittert–Zernike theorem has important implications for radio astronomy. With the exception of pulsars and masers, all astronomical sources are spatially incoherent. Nevertheless, because they are observed at distances large enough to satisfy the van Cittert–Zernike theorem, these objects exhibit a non-zero degree of coherence at different points in the imaging plane. By measuring the degree of coherence at different points in the imaging plane (the so-called \"visibility function\") of an astronomical object, a radio astronomer can thereby reconstruct the source's brightness distribution and make a two-dimensional map of the source's appearance.".
- Van_Cittert–Zernike_theorem wikiPageExternalLink watch?v=3Q_IwvWBQMc.
- Van_Cittert–Zernike_theorem wikiPageID "30860655".
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- Van_Cittert–Zernike_theorem wikiPageRevisionID "695651425".
- Van_Cittert–Zernike_theorem wikiPageWikiLink Adaptive_optics.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Angular_frequency.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Aperture_synthesis.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Atmosphere_of_Earth.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Band-pass_filter.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Band_matrix.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Bose–Einstein_correlations.
- Van_Cittert–Zernike_theorem wikiPageWikiLink CLEAN_(algorithm).
- Van_Cittert–Zernike_theorem wikiPageWikiLink Category:Optics.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Category:Radio_astronomy.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Coherence_theory.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Degree_of_coherence.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Electric_field.
- Van_Cittert–Zernike_theorem wikiPageWikiLink File:Van_Cittert-Zernike_theorem.jpg.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Fourier_transform.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Free-electron_laser.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Frits_Zernike.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Hanbury_Brown_and_Twiss_effect.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Interferometric_visibility.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Interstellar_medium.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Karl_G._Jansky_Very_Large_Array.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Light.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Maser.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Mutual_coherence_(physics).
- Van_Cittert–Zernike_theorem wikiPageWikiLink Near_and_far_field.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Nyquist–Shannon_sampling_theorem.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Outer_space.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Parsec.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Phasor.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Pieter_Hendrik_van_Cittert.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Pulsar.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Radio_astronomy.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Radio_telescope.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Refraction.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Refractive_index.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Solar_System.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Solid_angle.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Superposition_principle.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Taylor_series.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Visibility.
- Van_Cittert–Zernike_theorem wikiPageWikiLink Wavefront.
- Van_Cittert–Zernike_theorem wikiPageWikiLinkText "Mutual coherence function".
- Van_Cittert–Zernike_theorem wikiPageWikiLinkText "Van Cittert–Zernike theorem".
- Van_Cittert–Zernike_theorem wikiPageUsesTemplate Template:Aut.
- Van_Cittert–Zernike_theorem wikiPageUsesTemplate Template:Confusing.
- Van_Cittert–Zernike_theorem wikiPageUsesTemplate Template:More_footnotes.
- Van_Cittert–Zernike_theorem wikiPageUsesTemplate Template:Multiple_issues.
- Van_Cittert–Zernike_theorem wikiPageUsesTemplate Template:Reflist.
- Van_Cittert–Zernike_theorem subject Category:Optics.
- Van_Cittert–Zernike_theorem subject Category:Radio_astronomy.
- Van_Cittert–Zernike_theorem hypernym Formula.
- Van_Cittert–Zernike_theorem type Agent.
- Van_Cittert–Zernike_theorem type Redirect.
- Van_Cittert–Zernike_theorem type Science.
- Van_Cittert–Zernike_theorem type Sub-discipline.
- Van_Cittert–Zernike_theorem comment "The Van Cittert–Zernike theorem, named after physicists Pieter Hendrik van Cittert and Frits Zernike, is a formula in coherence theory that states that under certain conditions the Fourier transform of the mutual coherence function of a distant, incoherent source is equal to its complex visibility. This implies that the wavefront from an incoherent source will appear mostly coherent at large distances.".
- Van_Cittert–Zernike_theorem label "Van Cittert–Zernike theorem".
- Van_Cittert–Zernike_theorem sameAs Q2298452.
- Van_Cittert–Zernike_theorem sameAs Van_Cittert–Zernike-theorema.
- Van_Cittert–Zernike_theorem sameAs m.0gfdyt4.
- Van_Cittert–Zernike_theorem sameAs Q2298452.
- Van_Cittert–Zernike_theorem sameAs 范西特-泽尼克定理.
- Van_Cittert–Zernike_theorem wasDerivedFrom Van_Cittert–Zernike_theorem?oldid=695651425.
- Van_Cittert–Zernike_theorem isPrimaryTopicOf Van_Cittert–Zernike_theorem.