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تسجيل مستخدم جديدEmergent gravity fails to explain color-dependent galaxy-galaxy lensing signals from SDSS Dr7
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We test the Emergent Gravity(EG) theory using the galaxy-galaxy lensing technique based on SDSS DR7 data. In the EG scenario, we do not expect color dependence of the galaxy sample in the apparent dark matter predicted by EG, which is exerted only by the baryonic mass. If the baryonic mass is similar, then the predicted lensing profiles from the baryonic mass should be similar according to the EG, regardless of the color of the galaxy sample. We use the stellar mass of the galaxy as a proxy of its baryonic mass. We divide our galaxy sample into 5 stellar mass bins, and further classify them as red and blue subsamples in each stellar mass bin. If we set halo mass and concentration as free parameters, $Lambda$CDM is favored by our data in terms of the reduced $chi^2$ while EG fails to explain the color dependence of ESDs from the galaxy-galaxy lensing measurement.
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