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The dynamic of a tax on land value : concepts, models and impact scenario
This paper develops a spatial-dynamic framework to analyze the theoretical and quantitative effects of a Land Value Tax (LVT) on urban land markets, capital accumulation, and spatial redistribution. Building upon the Georgist distinction between produced value and unearned rent, the model departs from the static equilibrium tradition by introducing an explicit diffusion process for land values and a local investment dynamic governed by profitability thresholds. Land value V (x, y, t) and built capital K(x, y, t)evolve over a two-dimensional urban domain according to coupled nonlinear partial differential equations, incorporating local productivity A(x, y), centrality effects \mu(x, y), depreciation \delta, and fiscal pressure \tau . Analytical characterization of the steady states reveals a transcritical bifurcation in the parameter \tau , separating inactive (low-investment) and active (self-sustaining) spatial regimes. The equilibrium pair (V ^*, K^*) is shown to exist only when the effective decay rate \alpha = r + \tau - \mu(x, y) exceeds a profitability threshold \theta = \kappa + \delta / I_0, and becomes locally unstable beyond this boundary. The introduction of diffusion, D_V \Delta V, stabilizes spatial dynamics and generates continuous gradients of land value and capital intensity, mitigating speculative clustering while preserving productive incentives. Numerical simulations confirm these analytical properties and display the emergence of spatially heterogeneous steady states driven by urban centrality and local productivity. The model also quantifies key aggregate outcomes, including dynamic tax revenues, adjusted capital-to-land ratios, and net present values under spatial heterogeneity and temporal discounting. Sensitivity analyses demonstrate that the main qualitative mechanisms-critical activation, spatial recomposition, and bifurcation structure-remain robust under alternative spatial profiles (A, \mu), discretization schemes, and moderate differentiation of the tax rate \tau (x, y). From an economic perspective, the results clarify the dual nature of the LVT: while it erodes unproductive rents and speculative land holding, its dynamic incidence on built capital depends on local profitability and financing constraints. The taxation parameter \tau thus acts as a control variable in a nonlinear spatial system, shaping transitions between rent-driven and production-driven equilibria. Within a critical range around \tau_c, the LVT functions as an efficient spatial reallocation operator-reducing inequality in land values and investment density without impairing aggregate productivity. Beyond this range, excessive taxation induces systemic contraction and investment stagnation. Overall, this research bridges static urban tax theory with dynamic spatial economics by formalizing how a land-based fiscal instrument can reshape the geography of value creation through endogenous diffusion and nonlinear feedback. The framework provides a foundation for future extensions involving stochastic shocks, adaptive policy feedbacks, or endogenous public investment, offering a unified quantitative perspective on the dynamic efficiency and spatial equity of land value taxation.
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ℏ E : an action constant for quantum economics
This paper introduces the concept of an economic action constant, denoted ℏ E , as a structural analogue to Planck's reduced constant ℏ in quantum mechanics. Building on canonical quantization, we define ℏ E as the fundamental scale of irreducible uncertainty in macroeconomic dynamics through non-commuting observables ( X, PX ), derive uncertainty relations and a semi-classical limit, and study spectral properties under a double-well economic potential. Numerical simulations show that ℏ E governs regime transitions between deterministic, probabilistic, and highly unstable dynamics, with topological changes in phase-space and bifurcations emerging under harmonic modulation of ℏ E . We propose a systemic economic interpretation linking the magnitude of ℏ E to expectation coordination, institutional stability, and structural volatility, and provide historical analogies (post-war reconstruction, speculative bubbles, systemic crises). We finally outline an empirical strategy to estimate ℏ E from macro time series and agent-based simulations, opening a path toward a taxonomy of economic regimes under radical uncertainty
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Adaptation of quantum models to economic growth theories
- Only in english - Traditional economic growth theories, grounded in deterministic and often linear frameworks, fail to adequately capture the inherent uncertainty, non-commutativity, and complex interdependencies of modern economies. This paper proposes a novel approach by transposing fundamental concepts of quantum mechanics-such as superposition, operator algebra, and path integrals-into the realm of macroeconomic modeling. Within this quantum framework, core economic variables (capital, labor, and technological progress) are redefined as non-commuting operators acting on Hilbert spaces, and the state of the economy is represented as a dynamic wave function governed by a time-dependent Hamiltonian. The evolution of this economic wave function follows a generalized Schr{ö}dinger equation, developed here through Dyson series and Magnus expansions. We also define a quantum production function as the expected value of a composite operator, capturing the probabilistic nature of economic output. By integrating uncertainty relations analogous to Heisenberg's principle, and modeling economic fluctuations via Langevin dynamics, we extend the model to include dissipation, feedback loops, and non-linear interactions between variables. Finally, a Feynman path integral formalism is constructed to provide an alternative trajectory-based interpretation of economic dynamics. This quantum-inspired framework offers a rigorous and flexible methodology to rethink macroeconomic modeling under radical uncertainty, with potential applications in dynamic policy simulations and innovation-driven growth.
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Emerging countries' counter-currency cycles in the face of crises and dominant currencies
This article examines how emerging economies use countercyclical monetary policies to manage economic crises and fluctuations in dominant currencies, such as the US dollar and the euro. Global economic cycles are marked by phases of expansion and recession, often exacerbated by major financial crises. These crises, such as those of 1997, 2008 and the disruption caused by the COVID-19 pandemic, have a particular impact on emerging economies due to their heightened vulnerability to foreign capital flows and exports. Counter-cyclical monetary policies, including interest rate adjustments, foreign exchange interventions and capital controls, are essential to stabilize these economies. These measures aim to mitigate the effects of economic shocks, maintain price stability and promote sustainable growth. This article presents a theoretical analysis of economic cycles and financial crises, highlighting the role of dominant currencies in global economic stability. Currencies such as the dollar and the euro strongly influence emerging economies, notably through exchange rate variations and international capital movements. Analysis of the monetary strategies of emerging economies, through case studies of Brazil, India and Nigeria, reveals how these countries use tools such as interest rates, foreign exchange interventions and capital controls to manage the impacts of crises and fluctuations in dominant currencies. The article also highlights the challenges and limitations faced by these countries, including structural and institutional constraints and the reactions of international financial markets. Finally, an econometric analysis using a Vector AutoRegression (VAR) model illustrates the impact of monetary policies on key economic variables, such as GDP, interest rates, inflation and exchange rates. The results show that emerging economies, although sensitive to external shocks, can adjust their policies to stabilize economic growth in the medium and long term.
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Debt sustainability: structural differences between Northern bloc, Southern bloc and Eastern bloc in Europe
- Only in english - This article examines the current state of public debt across various blocs within the European Union (EU), particularly in light of the recent reform to the Stability Pact, enacted in April 2024. This reform strengthens the EU's capacity to enforce fiscal compliance among member states, aiming to harmonize public accounts and prevent a repeat of past sovereign debt crises. However, a single narrative on EU debt is inadequate given the distinct fiscal approaches among Northern, Southern, and Eastern European countries. The Northern bloc, including Germany and Sweden, is characterized by prudent fiscal management and robust institutional frameworks. Conversely, the Southern bloc, encompassing Greece, Italy, and France, struggles with high debt levels, often linked to expansive fiscal policies and structural economic challenges. The Eastern bloc, comprising emerging economies like Poland and Hungary, displays varied debt profiles reflective of post-communist economic reforms. This study categorizes EU countries into these three blocs, examining their distinct debt structures, fiscal policies, and economic foundations. Utilizing data on public debt, deficit levels, and foreign exchange reserves, it highlights the structural differences between these regions. Northern economies typically exhibit strong industrial sectors and positive trade balances, while Southern economies rely more on services and tourism, making them vulnerable to economic fluctuations. The Eastern bloc, meanwhile, occupies an intermediate position, with some countries showing competitive growth and others grappling with economic fragility. The analysis further explores the role of redistribution policies in debt accumulation, using per capita public spending data. Findings suggest that while redistribution contributes to public debt, high spending does not consistently correlate with elevated debt levels. Northern bloc countries, for instance, manage to sustain high public expenditures with relatively moderate debt increases, contrasting with the Southern bloc's reliance on debt to support similar policies. Ultimately, this article underscores the need for nuanced fiscal strategies tailored to the unique economic profiles within the EU, promoting fiscal stability while accommodating the diverse needs of its member states.
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Economic effects on households of an augmentation of the cash back duration of real estate loan
This article examines the economic effects of an increase in the duration of home loans on households, focusing on the French real estate market. It highlights trends in the property market, existing loan systems in other countries (such as bullet loans in Sweden and Japanese home loans), the current state of the property market in France, the potential effects of an increase in the amortization period of home loans, and the financial implications for households. The article points out that increasing the repayment period on home loans could reduce the amount of monthly instalments to be repaid, thereby facilitating access to credit for the most modest households. However, this measure also raises concerns about overall credit costs, financial stability and the impact on property prices. In addition, it highlights the differences between existing lending systems in other countries, such as the bullet loan in Sweden and Japanese home loans, and the current characteristics of home loans in France, notably interest rates and house price trends. The article proposes a model of the potential effects of an increase in the amortization period of home loans on housing demand, housing supply, property prices and the associated financial risks. In conclusion, the article highlights the crucial importance of household debt for individual and economic financial stability. It highlights the distortion between supply and demand for home loans as amortization periods increase, and the significant rise in overall loan costs for households. It also underlines the need to address structural issues such as the sustainable reduction in interest rates, the stabilization of banks' equity capital and the development of a regulatory framework for intergenerational lending to ensure a properly functioning market.
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Issues and risks of nationalization of foreign companies
This paper takes an in-depth look at the complexities and implications of nationalizing foreign companies in the context of international law. The first part defines nationalization and raises the legal, political and economic issues raised by this phenomenon. It highlights the tensions between national and international law, as well as the responsibilities of the host state towards foreign investors and the remedies available to them. The second part explores the implications of nationalization for economic and political stability, as well as the negotiation and arbitration processes between states and foreign investors. It also examines the impact on the host state's international reputation. The third part looks at the use of state ownership in economic warfare, its motivations, strategies and the need for international cooperation to prevent economic tensions and potential conflicts. Finally, the paper presents emblematic case studies of nationalizations, such as those in Bolivia, Russia and Argentina, highlighting the challenges, dynamics and implications associated with this complex phenomenon on the international stage. The case studies offer valuable insights into the different contexts, underlying motivations and consequences for the parties involved, while underlining the importance of careful, transparent management of these processes to minimize conflict and maximize long-term benefits for all concerned.
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Patents as business diplomacy tools
This article examines the role of patents in contemporary economic diplomacy, highlighting their growing importance in international negotiations and trade relations. Patents are defined as key intellectual property instruments allowing companies and research centers to protect their innovations and obtain a temporary monopoly on their exploitation. International patent cooperation is explored through agreements such as the Patent Cooperation Treaty (PCT), which facilitates the filing of international patents, and the European Patent Convention (EPC), which harmonizes procedures. deposit in Europe. Co-patents and triadic patents are also analyzed as forms of cooperation between companies and between states. The case of COVID-19 is used as a concrete example to illustrate patent diplomacy, highlighting both cooperation and competition between states in the development and distribution of vaccines. Despite international cooperation, diplomatic tensions and commercial rivalries have emerged, particularly between Western and Eastern countries. Patents have played a central role in these issues, with debates over lifting patents to ensure equitable access to vaccines.
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