弦理论在1968年问世后已过去58年，尽管 Sabine Hossenfelder 与 Peter Woit 等人的激烈批评，它仍是最有力的“万物理论”候选框架。批评者称其“not even wrong”，核心原因是其基本标度大约是10^-33厘米（10^-35米），几乎无法直接观测；再者到2000年代初，至少有10,500种六维紧致化方案，每种都对应不同的低能物理，这被称为“景观”问题。尽管如此，许多主流高能理论物理学者仍认为它在某种程度上有可能正确，学界因此分裂成研究者与反对者两阵营。

弦理论最初的吸引力来自1968年 Gabriele Veneziano 对强子散射的公式（Veneziano 振幅），后来被重解释为振动弦。即便随后人们认定强子是由夸克和胶子构成，弦理论框架仍持续存在，因为它给出了更深层数学结构并覆盖全部基本粒子类型，包括通过闭合弦环振动产生的假想引力子。该理论要求10维时空、额外6个紧致维度，这一假设曾颇具争议；但1984年 Green 与 Schwarz 显示手征异常可在弦理论中完全抵消后，推动了理论浪潮。进入1990年代，弦与量子场之间的对偶性网络不断出现，Strawminger 与 Vafa 以 D膜模型重现了 Bekenstein–Hawking 黑洞熵公式，这种与早期热力学结果一致的显式计算在当时罕见。

近期的“bootstrap”方法倒转了常规逻辑：先设定对称性、幺正性等基本原则，再从中导出可能的理论。在 Cheung 的2025年“Strings From Almost Nothing”中，引入 ultrasoftness 等假设后，得出的唯一高能兼容散射形态是 Veneziano 振幅与 Virasoro–Shapiro 振幅。2026年1月，Henriette Elvang 等人在 N=4 超对称并结合附加技术前提下证明，树级别最大超对称量子场论的 UV 完成必须是字符串。围绕这些假设是否能用于 UV 仍有争议：有观点认为量子引力的UV区可能是强烈涨落的类分形时空，使平直时空散射失效；反对者如 Grant Remmen 则坚持任何 UV 完整理论都应能给出散射振幅。当前共识仍偏中立，但弦理论重新被当作“受强约束的特殊候选”，而非纯数学装饰。

Fifty-eight years after its 1968 debut, string theory remains the leading theory-of-everything candidate despite sharp criticism from figures like Sabine Hossenfelder and Peter Woit. Critics call it “not even wrong,” partly because its fundamental scale is around 10^-33 cm (10^-35 m), far beyond direct observation, and because by the early 2000s at least 10,500 six-dimensional compactification solutions were known, each giving different low-energy physics—the notorious landscape problem. Yet many mainstream high-energy physicists still treat string theory as having at least partial validity, leaving the field polarized between believers and skeptics.

Its original appeal came from Gabriele Veneziano’s 1968 hadron-scattering formula, later reinterpreted as vibrating strings. Even after hadrons were later understood as quark–gluon systems, the framework persisted because it offered a deeper structure for all particle species, including a hypothetical graviton from closed-string loops. The requirement of 10-dimensional spacetime, with six curled extra dimensions, was controversial, but in 1984 Green and Schwarz showed chiral anomalies can self-cancel within string theory, energizing the program. Through the 1990s, dualities connected seemingly different string models and field theories, and the Strominger–Vafa D-brane construction reproduced the Bekenstein–Hawking black-hole entropy formula, a rare match that few alternatives could match.

Recent bootstrap work has reversed the logic: start from principles and infer theories. In Cheung’s August 2025 “Strings From Almost Nothing,” adding ultrasoftness and related assumptions left only the Veneziano and Virasoro–Shapiro amplitudes as compatible with high-energy behavior. In January 2026, Henriette Elvang’s team showed that with N=4 supersymmetry plus further technical assumptions, a maximally supersymmetric quantum field theory has a unique stringy ultraviolet completion at tree level. The debate is increasingly about whether these assumptions hold in the UV: some argue quantum-gravity UV spacetime may be fractal and strongly fluctuating so flat-space scattering fails, while others (e.g., Grant Remmen) insist any UV-complete theory should still predict UV scattering amplitudes. The field remains agnostic overall, but string theory is again viewed as a uniquely constrained scientific candidate rather than mere ornament.