The Business Cycle, Inflation, and Deflation Summary

Definition: Economic fluctuations around potential GDP; hard to explain.
Theories:
- Mainstream Business Cycle Theory
- Real Business Cycle (RBC) Theory

Key Concept: Real GDP fluctuations occur as aggregate demand varies against steady potential GDP growth.
Initial State: Potential GDP at $1.4 trillion, full employment at point A.
Expansion Phase: Potential GDP increases to $2.0 trillion; AD curve shifts rightward, leading to employment at point B (price rises from 100 to 110).
Slow Demand Increase: If AD rises slower than potential GDP, the economy approaches point C (slower growth, lower inflation).
Fast Demand Increase: Quick demand growth shifts AD to AD3, leading to point D (faster growth, higher inflation).

Core Idea: Economic fluctuations stem from random productivity changes, influenced mostly by technological shifts.
Productivity Effects:
- High productivity growth fosters expansion.
- Declines trigger recessions.
Investment Demand: Changes with productivity shifts; lower productivity leads to decreased investment.

Inflation Causes:
- Demand-pull: Driven by rising aggregate demand (e.g., increased money supply, government spending).
- Cost-push: Results from rising production costs (e.g., higher wages, raw material prices).
Stagflation: A scenario where rising prices coincide with falling real GDP.

Short-Run Phillips Curve (SRPC): Trade-off between inflation and unemployment; shows how changes in inflation impact unemployment rates.
Long-Run Phillips Curve (LRPC): Vertical line at the natural unemployment rate; reflects no trade-off in the long term when expected inflation equals actual inflation.

Causes: Occurs when aggregate demand grows slower than supply.
Consequences: Redistribution of income, lower GDP, and employment issues.
Ending Deflation: Requires increasing money growth rate above real GDP growth minus velocity changes.