Many societies became Muslim gradually, without conquest by Muslim rulers. Explanations of this process typically focus on Muslim traders, proselytizing ‘holy men’, and the conversion of ruling elites, as the limited sources suggest. Yet it cannot be assumed that Islamization always made sense for elites as a power-enhancing stratagem, or that rulers or holy men were willing or able to shape th...

Measurements of standard candles and measurements of standard rulers give an inconsistent picture of the history of the universe. This discrepancy can be explained if photon number is not conserved as computations of the luminosity distance must be modified. I show that photon number is not conserved when photons mix with chameleons in the presence of a magnetic field. The strong magnetic field...

human history has been witness to the emergence of great men and women who illustrated the sufferings and wishes of mankind. they have bravely put in hard effort to resist long-standing and reactionary traditions of their own society and to fight oppressors, and at the same time, the comfort-seeking opportunists have endeavored to derail their efforts and to project a tarnished image of these c...

Many experimental factors and uncontrollable factors may introduce errors in the distance measurement by continuous wave electron paramagnetic resonance. To deal with this problem, several C60 nitroxide diradical adducts with rigid structure and definite molecular dimension were used as distance calibration rulers. Based on the improvement of distance calculation program via adding simulation p...

One of the obstacles to democratic development is the reluctance of political leaders to leave office. This paper argues that alongside democratic constraints and accountability, leaders’ career concerns — specifically, the possibility of post-tenure careers — is an important factor behind their rotation in office. While literature exists about leaders’ exit and fate, we lack a systematic under...

Rulers of weakly institutionalized states constantly fear coup attempts. The risk of coups may lead rulers to exclude certain ethnic groups from power—despite creating incentives for excluded groups to rebel against the government. But under what conditions do leaders perceive strong threats? Focusing on post-independence SubSaharan Africa, this paper argues that leaders of countries containing...