https://haifei-home.pages.dev/en/tags/second-quantization/Recent content in Second Quantization on Haifei's HomeHugoenhfwang132@gmail.com (hfwang132)hfwang132@gmail.com (hfwang132)This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.Sat, 09 Aug 2025 14:16:03 +0800https://haifei-home.pages.dev/en/post_20250809_%E5%BD%93%E6%88%91%E4%BB%AC%E5%81%9A%E4%BA%8C%E6%AC%A1%E9%87%8F%E5%AD%90%E5%8C%96%E7%9A%84%E6%97%B6%E5%80%99-%E6%88%91%E4%BB%AC%E7%A9%B6%E7%AB%9F%E5%9C%A8%E5%81%9A%E4%BB%80%E4%B9%88/Sat, 09 Aug 2025 14:16:03 +0800hfwang132@gmail.com (hfwang132)https://haifei-home.pages.dev/en/post_20250809_%E5%BD%93%E6%88%91%E4%BB%AC%E5%81%9A%E4%BA%8C%E6%AC%A1%E9%87%8F%E5%AD%90%E5%8C%96%E7%9A%84%E6%97%B6%E5%80%99-%E6%88%91%E4%BB%AC%E7%A9%B6%E7%AB%9F%E5%9C%A8%E5%81%9A%E4%BB%80%E4%B9%88/<p><strong>First quantization cannot describe superpositions of particle number, let alone dynamics in which particle number changes.</strong></p> <p>The terms first quantization and second quantization can easily lead one to believe that they are equivalent, and that one can use whichever is more convenient, much like the Schrödinger and Heisenberg pictures. This is not the case. The descriptive power of second quantization is strictly greater than that of first quantization. First quantization is merely a simplified description of second quantization for situations with a fixed particle number, and is intrinsically deficient.</p>