Comparing Beliefs, Surveys and Random Walks

Survey propagation is a powerful technique from statistical physics that has been applied to solve the 3-SAT problem both in principle and in practice. We give, using only probability arguments, a common derivation of survey propagation, belief propagation and several interesting hybrid methods. We then present numerical experiments which use WSAT (a widely used random-walk based SAT solver) to quantify the complexity of the 3-SAT formulae as a function of their parameters, both as randomly generated and after simplification, guided by survey propagation. Some properties of WSAT which have not previously been reported make it an ideal tool for this purpose -- its mean cost is proportional to the number of variables in the formula (at a fixed ratio of clauses to variables) in the easy-SAT regime and slightly beyond, and its behavior in the hard-SAT regime appears to reflect the underlying structure of the solution space that has been predicted by replica symmetry-breaking arguments. An analysis of the tradeoffs between the various methods of search for satisfying assignments shows WSAT to be far more powerful that has been appreciated, and suggests some interesting new directions for practical algorithm development.Comment: 8 pages, 5 figure

Israel's 'Tent Protests': the chilling effect of nationalism

The Israeli ‘Tent Protest’ movement enjoyed wide popular support, but displayed a distinct lack of political radicalism. Not only did calls for discrete welfare policies replace explicit anti-capitalism, but there was a widespread insistence on the movement’s ‘apolitical’ nature and an avoidance of any direct confrontation with the neoliberal Netanyahu government or calls for new elections. The article argues that these anomalies can be explained by the chilling effect of the patriotic, state-loyalist discourses which reached unprecedented prominence in Israeli society in the past year. This led movement participants to avoid at all costs being perceived as left-wing and disloyal, and created an atmosphere of deliberate self-censorship which silenced any engagement with the Israeli–Palestinian conflict during the mobilization. The movement is understood here as an all-too-brief interlude in Israel’s ongoing move away from democracy

Against the wall: anarchist mobilization in the Israeli-Palestinian conflict

Anarchists Against the Wall is an Israeli action group supporting the popular Palestinian struggle against segregation and land confiscation in the West Bank. Incorporating participant observation and recent theories of social movements and anarchism, this article offers a thick cultural account of the group’s mobilization dynamics, and assesses the achievements and limitations of the joint struggle. Three dimensions—direct action, bi-nationalism, and leadership—highlight the significance of anarchist practices and discourses to an informed assessment of the group’s politics of nonviolent resistance. The effectiveness of the campaign is then examined, calling attention to the distinction among immediate, mediumterm, and revolutionary goals

Olive green: environment, militarism and the Israel defense forces

Militaristic societies are ones in which the armed forces enjoy a privileged material and cultural status, and where military priorities and frames of thinking play a key role in policymaking and political culture (Vagts 1981, Evans and Newnham 1988). Militarism is not limited to direct governance by uniformed personnel (“praetorianism”), but may instead coexist with substantive democratic institutions (Ben Eliezer 1997). Thus, contemporary societies described as militaristic are as politically diverse as Switzerland and Burma, North and South Korea, Jordan and Israel. This chapter explores the interface between environmental and military issues in Israel, placing it within the context of the changing fortunes of Israeli militarism. In particular, it is argued that growing public willingness to challenge the military’s environmentally destructive behavior in the last decades was linked to wider transformations in Israeli society. The Oslo Accords and the rise of liberalindividualist outlooks associated with globalization and consumer culture weakened the country’s founding collectivist ideology in favor of material values associated with quality of life. In this context, the military lost its previous immunity to public criticism, and environmental concerns, formerly considered luxuries in comparison with security matters, were able to gain ground in the public sphere alongside other civil agendas. The chapter begins by stating the case for viewing Israel as a militaristic society. It then surveys the military’s environmental activity and the environmental destruction it has wrought, while also noting some early successes in the area of nature conservation. Finally, it discusses how, since the 1990s, the environmental movement and affected residents, as well as the Ministry of Environment and State Comptroller, have pushed the military to clean up its act

Anarchism and multiculturalism

Anarchism is strongly opposed to racism and bigotry, and celebrates cultural pluralism and the endless diversity of the human race. At the same time, anarchists are very critical of modern “multiculturalism” as a state-driven population and immigration management agenda. The chapter examines this critique, while offering an account of original anarchist approaches to identity and community conceived on an ethno-cultural basis. The anarchist critique of multiculturalism has several dimensions, including its continued reliance on the state, and its obviation of social antagonism in favour of competing demands for status and resources within existing arrangements of power. On this reading, multiculturalism dissolves the potential for solidarities that would challenge the given society by redefining which identities enjoy first-order relevance (namely, ethnic or religious ones) and allowing the state, and its technocratic machinations of coercive urban governance, to engage with groups (or their declared leaders) on that basis. In addition, anarchists have criticised multiculturalism as a privileged liberal ideology that pushed sections of the white working class population “left behind” by neoliberal globalisation into the hands of the far right. At the same time, anarchists celebrate the grassroots, quotidian, non-state-sanctioned forms of “multiculturalism” that people arguably practice on a daily basis – trying to get along with people from other backgrounds and avoiding cultural imposition. These have a long history in the Left, although under other names ("working class internationalism", "transnational solidarity", “cosmopolitanism” etc.). A fair amount of “classical" anarchist writing thus engaged with topics akin to multiculturalism, albeit in terms of "nations," "nationalities," or "peoples." The chapter surveys some of these, from Bakunin’s writings on the rights of "nationalities" to exist and exercise their independence, through Kropotkin’s discussions of national liberation, and on to Rocker’s wide-ranging considerations on state-driven identity in Nationalism and Culture. Many anarchists wrote positively of non-Western cultures and their equality, especially Elisee Reclus, Peter Kropotkin and Jean Grave. These anarchist notions of cultural pluralism engage explicitly with class conflict in a way that contemporary liberal conceptions of multiculturalism do not. Finally, the chapter looks at anarchist responses to contemporary cultural pluralism. The chief argument here is that rather than seeking a blueprint for social relations among diverse groups in the absence of the state, anarchist theory should focus on present-tense questions relevant to its emergent strategic outlooks on social transformation, asking how encounters in mixed communities impact on political-cultural dynamics and how anarchists can use grassroots forms of encounter to push forward radical agendas. Here, the main issue remains the politics of solidarity across difference and asymmetric power. Dilemmas surrounding this issue are explored in two key contexts: settler-colonial societies and societies absorbing immigration

Observing Molecular Spinning via the Rotational Doppler Effect

When circularly polarized light is scattered from a rotating target, a rotational Doppler shift (RDS) emerges from an exchange of angular momentum between the spinning object and the electromagnetic field. Here, we used coherently spinning molecules to generate a shift of the frequency of a circularly polarized probe propagating through a gaseous sample. We used a linearly polarized laser pulse to align the molecules, followed by a second delayed pulse polarized at 45{\deg} to achieve unidirectional molecular rotation. The measured RDS is orders of magnitude greater than previously observed by other methods. This experiment provides explicit evidence of unidirectional molecular rotation and paves the way for a new class of measurements in which the rotational direction of molecular reagents may be monitored or actively controlled.Comment: Submitted also to Nature Photonics, current status: "under consideration

Israel's ‘Tent Protests’: The Chilling Effect of Nationalism

This is an Accepted Manuscript of an article published in Social Movement Studies on 1 August 2012, available online: http://www.tandfonline.com/doi/pdf/10.1080/14742837.2012.708832The Israeli ‘Tent Protest’ movement enjoyed wide popular support, but displayed a distinct lack of political radicalism. Not only did calls for discrete welfare policies replace explicit anti-capitalism, but there was a widespread insistence on the movement’s ‘apolitical’ nature and an avoidance of any direct confrontation with the neoliberal Netanyahu government or calls for new elections. The article argues that these anomalies can be explained by the chilling effect of the patriotic, state-loyalist discourses which reached unprecedented prominence in Israeli society in the past year. This led movement participants to avoid at all costs being perceived as left-wing and disloyal, and created an atmosphere of deliberate self-censorship which silenced any engagement with the Israeli–Palestinian conflict during the mobilization. The movement is understood here as an all-too-brief interlude in Israel’s ongoing move away from democracy

POLÍTICA PREFIGURATIVA, CATÁSTROFE E ESPERANÇA

A “política prefigurativa” tornou-se um termo comum para o ethos radical da unidade entremeios e fins. Nesta prática ética revolucionária, principalmente devido à tradição anarquista, a lutacontra a dominação está ligada à construção imediata de alternat ivas sociais. Menos atenção tem sidodada à maneira peculiar de imaginar o tempo que esse conceito invoca. Este artigo mostra como oconceito de “prefiguração” se baseia em um enquadramento temporal específico, inconscientementeextraído da teologia cristã, em que se pensa que o futuro irradia para trás em seu passado. Traçandoa prefiguração dos Padres da Igreja a ressurgimentos politizados nos Diggers e na Nova Esquerda,argumento que esse enquadramento temporal está de fato conectado a um “processo de re afirmação”mental, comum entre muitos revolucionários que extraíram confiança da noção de que estavampercebendo um caminho histórico pré-ordenado