水平皮筋
Horizontal Elastic Band
两端固定的水平皮筋，中间小球上下振动。0–2 Hz：皮筋随球成直线（端点不动）；超过 2 Hz：形变波缓慢出现并随频率逐步增强，由疏到密向外传递。
A horizontal band fixed at both ends with an oscillating ball at the center. 0–2 Hz: the band stays straight as the ball moves (anchors fixed). Above 2 Hz: waves appear gently and grow stronger with frequency, propagating outward from sparse to dense.
类比说明：本演示用水平皮筋类比空能介质的同步/滞后，不是真实引力波模拟。演示中 2 Hz 起即出现波形，是为肉眼可见而故意压低的临界频率；真实空能介质以 ≈ c 响应，并合源辐射主要在几十至数百 Hz 等天体物理频段，与皮筋参数不可直接对比。
Analogy note: this demo uses a horizontal rubber band to illustrate medium sync vs. lag — not a real gravitational-wave simulation. Waves appear above 2 Hz here because the threshold is deliberately lowered for visibility; the real Kong-Neng medium responds at ≈ c, with astrophysical radiation typically in the tens to hundreds of Hz band — not comparable to rubber-band parameters.
调节频率：0 Hz 时小球静止在平衡位置。
Adjust frequency: at 0 Hz the ball rests at equilibrium.
演示说明：左右端点固定；≤2 Hz 皮筋为直线；超过 2 Hz 波形逐步出现、变密。上述频率分区均为皮筋教学缩放，非 LIGO 或 SGT 定量预言。
Demo note: fixed anchors; ≤2 Hz straight band; above 2 Hz waves grow gradually denser. All frequency zones are rubber-band teaching scales, not LIGO bands or quantitative SGT predictions.