The most promising heating source under the given constraints is the central AGN, where the required fine-tuning can be accomplished through a feedback mechanism between the gas accreted onto the central AGN massive black hole and the AGN output power. One possibility of such mechanism discussed by Churazov et al (2002)  involves classical Bondi accretion theory which provides a link between the accretion rate and the gas parameters in the ICM, notably the gas entropy. As discussed by Kaiser and Binney (2003) , an AGN outburst produces bubbles of high-entropy gas near the bottom of the gravitational potential well, disturbing the stable hydrostatic equilibrium characterized by a stratified specific entropy profile. Following this disturbance, the accretion rate is altered and the AGN goes into a quiescent stage, during which the specific entropy is redistributed through the ICM by the buoyant bubbles and the entropy excess is radiated away. When the excess entropy has been lost, the density of the gas at the bottom of the well becomes again extremely large and a further outburst of the AGN is stimulated when some of this dense gas accretes onto the central massive black hole, starting the next cycle of the system.
It should be noted here that already with the precision available back then, which allowed one only to measure distances up to around 10 light years, it was possible to show that most of the stars should be much farther away: by measuring the distances of as many as possible nearby stars, one can get a value for the average density of stars (the average amount of stars per cubic light year), and then simple counting of the visible stars and dividing this by the average density gives a (lower) bound on the size of the universe! Obviously this assumes that the density of stars is more or less the same in all regions where we can see stars, but just comparing the angular distances of the star in the sky, it is clear that this assumption seems to be justified. But even if one would use a far higher density of stars, this still would imply a very large universe, because of the very large number of stars which can be seen with telescopes.
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To simply say that your research will look at ways to deal with power grid instabilities indicates to the reader that you're working on solving a problem, but not why that problem is significant enough to work on. To indicate the significance of the problem, it would be necessary to briefly explain: