![]() The synthetic data sets were designed to have properties that are similar to the EHT M87 visibility amplitudes (e.g., prominent amplitude nulls). To objectively evaluate the fidelity of the images reconstructed by our surveys-i.e., to select imaging parameters that were independent of expert judgment-we performed these surveys on synthetic data from a suite of model images as well as on the M87 data. > To explore the dependence of the reconstructed images on imaging assumptions and impartially determine a combination of fiducial imaging parameters, we introduced a second stage of image production and analysis: performing scripted parameter surveys for three imaging pipelines. Section 6, in turn, confirms the statements from the TED talk: Some of these differences are attributable to different assumptions about the total compact flux density and systematic uncertainties (see Table 2). In contrast, the ring azimuthual profile, thickness, and brightness varies substantially among the images. For both RML teams and both CLEAN teams, the ring has a diameter of approximately 40 μas, with brighter emission in the south. All four images show an asymmetric ring structure. > Figure 4 shows these first four images of M87. After ensuring image consistency through a variety of blind metrics (including normalized cross-correlation, Equation (15)), we compared the independently reconstructed images from the four teams. > The imaging teams worked on the data independently, without communication, for seven weeks, after which teams submitted images to the image comparison website using LCP data (because the JCMT recorded LCP on April 11). Section 5.2 confirms the statements from the press conference today: ![]() Imaging the Central Supermassive Black Hole" ( ): I briefly(!) looked at the papers that were published today ("First M87 Event Horizon Telescope Results" I-VI) and while I'm anything but an expert when it comes to radioastronomy and imaging technology (I'm more a theoretical physics/mathematical general relativity kind of guy), I came across the following statements which, to me, all suggest that they've at least evaluated the data with due diligence (emphases all mine): And at the end, when the four teams met up last year, they had supposedly arrived at very similar-looking images. to not communicate with each other at all, and use (more or less) whatever interpolation algorithm they thought would fit the data best. Moreover, in the NSF press conference today it was said that they had four different teams in four different locations across the globe last year, working on interpolating the data and generating the images and they basically asked the teams to lock themselves in, i.e. That being said, it seems your concerns are being addressed in the TED talk you linked to from 8:45 onward? Not sure why you're getting downvoted because (as a physicist) I'd say that especially in the face of a high-level discovery like today's, a healthy amount of scepticism is a good thing.
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