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The Heart of Quantum Mechanics

This work addresses quantum superposition and interference phenomena. It explains concepts such as the wave-particle duality, quantum entanglement, and the Aharonov-Bohm effect through electron and photon experiments. It examines the statistical nature of quantum mechanics and its effects on chiral systems. While quantum superposition is a fundamental property for subatomic particles and quantum systems, according to the sources provided, it does not directly and observably affect macroscopic objects in our daily lives (such as cats, people, or tables). Based on Mark P. Silverman's book, the reasons for this and the limitations of the effect of superposition on everyday objects are detailed below: 1. The Wave Function Problem of Macroscopic Objects Examples such as "Schrödinger's Cat," frequently encountered in popular science narratives, lead to a major misunderstanding in applying superposition to everyday life. The author states that the idea that living things or everyday objects, such as cats or chickens, possess a "wave function" is incorrect, and that such examples are "quantum flapdoodles." The reason a person doesn't experience diffraction when passing through a doorway, or a cat can't be both dead and alive at the same time, is that these complex macroscopic systems lack the coherence to sustain quantum superposition. 2. Impossibly Small Interference Patterns The way to prove that an object is in a state of superposition (for example, being in two different places at the same time) is to observe an interference pattern. However, as the mass of the object increases, the fringe interval (period) of this pattern becomes impossibly small. • Example: Even for a microscopic dust particle weighing only 1.7 nanograms (approximately 10⁻¹⁸ atomic mass units), the period of the quantum interference pattern is approximately 3.8×10⁻²³ meters. This distance is billions of times smaller than the diameter of a proton. Therefore, it is in principle impossible to observe such a quantum effect for much larger objects such as a cat or a chicken. 3. Environmental Interaction and Decoherence (Loss of Coherence) The most important physical reason why superposition is not observed in everyday objects is that objects are constantly interacting with their environment (heat, light, air molecules, etc.). • Thermal Radiation: Every object with a temperature above absolute zero emits energy. This radiation "gives away" the object's position and breaks the superposition state (decoherence) by eliminating quantum uncertainty. • Temperature Effect: Sources calculate that for a macroscopic object, such as "Schrödinger's chicken," to maintain its superposition (prevent decoherence), it would need to be frozen at approximately 10⁻⁴ Kelvin (very close to absolute zero), which is not possible in everyday life. • Experimental Evidence: In experiments with large molecules such as C70, it has been observed that when the temperature of the molecules is increased to 3000 Kelvin, the quantum interference pattern (evidence of superposition) completely disappears due to thermal radiation. 4. Exceptions: Macroscopic Quantum Systems Although ordinary objects in everyday life do not exhibit superposition, quantum effects can be observed at the "macroscopic" level under certain special conditions. Sources describe systems such as superconductors, superfluids, and Bose-Einstein condensates as exceptions where coherent superposition states can occur at the macroscopic scale. However, these are not everyday objects at room temperature, but systems created under special physical conditions. In short, although everything is a quantum system at the most fundamental level, the mass of everyday objects and their interactions with their environment prevent the strange effects of quantum superposition (like being in two places at once) from manifesting in the macroscopic world.