【People's Education Press】High School Physics: Elective Compulsory Course III: From Chip Miniaturization to Atomic Nuclei

Welcome to one of the most fascinating intersections in physics:Nuclear Physics. At the beginning of this chapter, we aim to challenge a common misconception—that quantum mechanics is merely a theoretical concept confined to academic ivory towers. In fact, your smartphone is essentially an application of quantum mechanics tucked into your pocket.

1. The 'Quantum Wall' of Chip Miniaturization

When Moore's Law drives chips into 3nm node, electrons are no longer moving like tiny balls through wires. According to de Broglie's hypothesis, electrons exhibit pronouncedwave-like behavior. If chip designers ignore the probabilistic distribution of the wave function, electrons may tunnel through insulating layers via the 'quantum tunneling' effect, leading to chip failure.

2. A Turning Point in History: The 1927 Solvay Conference

The debate among physics giants such as Einstein and Bohr at the Fifth Solvay Conference on the nature of quantum mechanics not only established the Copenhagen interpretation but also laid the theoretical foundation for understanding solid-state physics and subsequent deep probing into atomic nuclei. From that moment onward, humanity began to gain active control over the microscopic laws of matter.

3. Macroscopic Observation of de Broglie Matter Waves

Formula λ = h / mv reveals that all matter possesses wave-like properties. The extremely small value of Planck's constant ($6.63 \times 10^{-34} J \cdot s$) is the fundamental reason why wave behavior in macroscopic objects is difficult to observe. For a running person, whose mass $m$ is very large, the resulting wavelength $\lambda$ becomes smaller than the diameter of a proton—far beyond the detection capability of current experimental methods.

QUESTION 1

Briefly describe the core idea of de Broglie's matter wave hypothesis, and explain why we do not observe wave-like behavior in a running person in daily life?

The core is λ = h/p; we cannot observe it because human momentum is too large, resulting in an extremely short wavelength far beyond current detection limits.

The core is energy conservation; we cannot observe it because humans are not microscopic particles and do not exhibit wave-particle duality.

QUESTION 2

Write the nuclear reaction equations for the following artificial transformations: (1) ${ }_{11}^{23} \mathrm{Na}$ (sodium nucleus) captures one α particle and emits one proton. (2) ${ }_{13}^{27} \mathrm{Al}$ (aluminum nucleus) captures one α particle and emits one neutron. (3) ${ }_{8}^{16} \mathrm{O}$ (oxygen nucleus) captures one neutron and emits one proton. (4) ${ }_{14}^{28} \mathrm{Si}$ (silicon nucleus) captures one proton and emits one neutron.

Option A: (1) Na + He → Mg + H; (2) Al + He → P + n; (3) O + n → N + H; (4) Si + H → P + n

Option B: (1) Na + H → Ne + He; (2) Al + n → Mg + H; (3) O + He → Ne + n; (4) Si + He → S + n

QUESTION 3

Identify the type of each nuclear reaction: (1) $^{24}_{11}\text{Na} \rightarrow ^{24}_{12}\text{Mg} + ^{0}_{-1}\text{e}$ (2) $^{235}_{92}\text{U} + ^{1}_{0}\text{n} \rightarrow ^{140}_{54}\text{Xe} + ^{94}_{38}\text{Sr} + 2^{1}_{0}\text{n}$ (3) $^{19}_{9}\text{F} + ^{4}_{2}\text{He} \rightarrow ^{22}_{10}\text{Ne} + ^{1}_{1}\text{H}$ (4) $^{2}_{1}\text{H} + ^{3}_{1}\text{H} \rightarrow ^{4}_{2}\text{He} + ^{1}_{0}\text{n}$

Beta decay, heavy nucleus fission, artificial transmutation, light nucleus fusion

Alpha decay, light nucleus fusion, natural radioactivity, heavy nucleus fission

QUESTION 4

Which of the following statements about the relationship between quantum physics and the macroscopic world is incorrect?

One limitation in modern chip manufacturing is the quantum tunneling effect of electrons.

Quantum mechanics only needs to be considered in microscopic laboratories.

Macroscopic objects also exhibit wave-like behavior, but their wavelengths are too short to be observed.

QUESTION 5

In de Broglie's hypothesis λ = h/p, how does the de Broglie wavelength change if the object's velocity increases?

Wavelength increases

Wavelength decreases