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The sub-millimeter observations of the luminous obscured quasar SDSS J1356+1026 with AtacamaLarge Millimeter/submillimeter Array (ALMA) provide insights into molecular gas dynamics duringa merger, Active Galactic Nuclei (AGN) feedback on molecular gas, and episodic AGN activity on10 Myr time scales. I have summarized the highlights of the study below.SDSS J1356+1026 contains two merging nuclei, with the primary galaxy likely of early type.Given the high molecular content found in the system (M mol ? 9 +19?6 × 10 8 M ? ), Sun et. al.speculates that the secondary galaxy was a disk galaxy which brought in the majority of the gas. Inthis scenario, the cold gas from the secondary was disrupted during the encounter. Roughly a thirdof the gas sank into the primary nucleus and formed a compact disk (nucleus, r ? 300 pc, M mol ?3 +6?2 × 10 8 M ? ), while half of the gas is now in an extended tidal tail (W arm , r ? 5 kpc, M mol ?5 +11?3 × 10 8 M ? ), which is one of the most massive molecular tidal features known.In addition to a compact disk, a red-shifted high-velocity component deviating from rotation at theN nucleus is found. It has a compact size of ? 300 pc and a velocity of ? 500 km s ?1 . Although theorigin of this gas is not clear, authors suspects that it is an outflow driven by the AGN. Theestimated star formation rate limits SFR < 16 M yrmolecular content and SFR < 21 M yr?1?1calculated from the carbon monoxide (CO)calculated from theFar-infrared Spectral EnergyDistribution (FIR-SED) decomposition, disfavors star formation as the driving mechanism. Amolecular outflow with M ? 350 M yr ?1 could expel all gas in the nucleus in ? 1 Myr and all themolecular gas in the system in ? 3 Myr. It is one of the most compact CO molecular outflowsdiscovered, and the corresponding dynamical time is short.The kinetic luminosity of this outflow E ? 3 × 10 43 ergs s ?1 is only ? 0.3% of the AGN bolometricluminosity L bol ? 10 46 ergs s ?1 . Its low momentum boost rate is consistent with the prediction thatcompact AGN outflows tend to be momentum conserving. The compact molecular outflowdiscovered and the extended ionized outflow are likely induced from two episodes of AGN activity,varying on a time scale of 10 Myr.SDSS J1356+1026 is an example of a molecular outflow that can effectively disturb or deplete themolecular reservoir in the galaxy. Molecular outflows identified by high velocity OH absorptionfeatures are found to be common among AGN. As demonstrated in the work, spatially resolved COobservations provide a complementary and model independent technique to measure the size andmass, and to infer the mass-lost rate of the outflow. In the end, whether AGN feedback is asuccessful model to account for the absence of luminous blue galaxies and the cut-off of the galaxyluminosity function depends on both the frequency and the mass-lost rate of molecular outflows asa function of AGN luminosity. Furthermore, both molecular and ionized outflows are found to beubiquitous in luminous quasars and can coexist, but we do not fully understand how they arerelated. Also, the connection between the compactness and the low momentum boost rate ofmolecular outflows, as hinted by SDSS J1356+1026, requires confirmation from a larger spatiallyresolved sample. These outstanding questions could be answered with systematic and spatiallyresolved observations of molecular gas in a sample of AGN covering a range of luminosities andionized outflow properties.As demonstrated in this work, with its great sensitivity and resolution, ALMA is well suited forresolving molecular outflows on sub-kpc scales to as far as redshift z = 0.1, and is therefore apowerful tool to bring our understanding of AGN feedback to the next level.