GENEVA – At the dawn of a new year, the world is in the midst of several epic transitions. Economic growth patterns, the geopolitical landscape, the social contract that binds people together, and our planet’s ecosystem are all undergoing radical, simultaneous transformations, generating anxiety and, in many places, turmoil.From an economic standpoint, we are entering an era of diminished expectations and increased uncertainty. In terms of growth, the world will have to live with less. To understand the implications of this, consider the following: If the global economy grew at its pre-crisis pace (more than 5% per year) for the foreseeable future, its size would double in less than 15 years; at 3%, doubling world GDP would take about 25 years.This makes a significant difference to the speed at which wealth creation occurs, with profound effects on expectations. We ignore the power of compound growth to our detriment.As for uncertainty, the world’s four largest economies are currently undergoing major transitions. The US is striving to boost growth in a fractured political environment. China is moving from a growth model based on investment and exports to one led by internal demand. Europe is struggling to preserve the integrity of its common currency while resolving a multitude of complex institutional issues. And Japan is trying to combat two decades of deflation with aggressive and unconventional monetary policies.For each, the formulation and outcome of complex and sensitive policy decisions implies many "unknowns,” with global interdependence heightening the risk of large unintended consequences. For example, the US Federal Reserve’s policy of quantitative easing (QE) has had a major effect on other countries’ currencies, and on capital flows to and from emerging markets.When QE was launched, it was the least flawed of the available policies, and it averted a catastrophic global depression. But its downsides are now apparent, and its abatement in 2014 could fuel further uncertainty.The Fed’s QE policy, and variants of it elsewhere, have caused the major central banks’ balance sheets to expand dramatically (from $5-6 trillion prior to the crisis to almost $20 trillion now), causing financial markets to become addicted to easy money. This has led, in turn, to a global search for yield, artificial asset-price inflation, and misallocation of capital.As a result, the longer QE lasts, the greater the collateral damage to the real economy. The concern now is that when the Fed begins to taper QE and dollar liquidity drains from global markets, structural problems and imbalances will resurface. After all, competitiveness-enhancing reforms in many advanced economies remain far from complete, while the ratio of these countries’ total public and private debt to GDP is now 30% higher than before the crisis.This source of uncertainty coincides with weakening performance in many emerging countries. Back in 2007, emerging-market growth was expected to outpace that of advanced economies by a wide margin, before converging. Today, the advanced economies contribute more to global GDP growth than emerging countries, where growth is forecast to average 4% in the coming years.Economic conditions are slowly improving in high-income countries, but a range of downward pressures may persist for years. The US economy, for example, remains stuck in a subpar recovery: inflation is too low and unemployment is too high. Official data have often been better than expected, reflecting how resilient, adaptive, and innovative the US economy is, but pre-crisis consumer-spending and growth patterns are unlikely to recur.Improvements in the eurozone are real but tenuous. The good news is that the disaster predicted by many pundits has been avoided, and the recession is coming to an end. But improvement does not mean resurgence: achieving the robust growth needed to reduce high unemployment, lower the debt/GDP ratio, and improve the fiscal outlook remains elusive. The greatest risk for the eurozone in the foreseeable future is not a disorderly exit by some countries, but rather a prolonged period of stagnant growth and high unemployment.Meanwhile, the emerging-market slowdown may well persist, particularly in the largest economies. Over the past 15 years, the BRICs (Brazil, Russia, India, and China) have achieved remarkable progress, but their reforms – including new banking regulations and currency regimes – have been among the least difficult to implement.So-called second-generation reforms, which are more structural in nature, are vital to long-term growth but much more difficult to realize. Elimination of subsidies, labor market and judicial reforms, and effective anti-corruption measures are politically charged and often are blocked by powerful vested interests.The global growth slowdown is taking place against a backdrop of rising economic inequality, owing to labor’s declining share of national income – a worldwide phenomenon, resulting from globalization and technological progress, that poses a serious challenge to policymakers. Systems that propagate inequality, or that seem unable to stem its rise, contain the seeds of their own destruction. But in an interdependent world, there is no obvious solution, because the high mobility of capital fuels global tax competition.Even in stronger-performing countries, such as the US or the United Kingdom, faster GDP growth has yet to boost real incomes. In the US, for example, median household income has fallen by more than 5% since the recovery began. More generally, lower growth is fueling popular protest and social unrest, particularly in countries that were growing rapidly (for example, Brazil, Turkey, and South Africa), owing to the impact of rising living standards on expectations.In such a charged social and political context, reviving high-quality economic growth is crucial. But where will it come from? Technological progress is a distinct, but highly uncertain, possibility. Many disruptive technologies (for example, advanced robotics, next-generation genomics, energy storage, renewable energy, and 3D printing) could drive future growth, but their full potential can be realized only in the distant future.Klaus Schwab is Founder and Executive Chairman, World Economic Forum.Copyright: Project Syndicate.