WASHINGTON, March 19 (Xinhua) -- The White House said U.S. President Donald Trump and his Ukrainian counterpart Volodymyr Zelensky in a phone call on Wednesday agreed to "a partial ceasefire against ...

注意到： \begin{align} \prod_{i=1}^{3} p_i &\approx \color{red}{3}.000000000000000 \times 10^{1}\\[.2cm] \prod_{i=1}^{30} p_i &\approx \color{red}{3.}161005464041760 \times 10^{46} ...

3月18日，美国总统特朗普和俄罗斯总统普京进行了一次长时间（预计超过两小时）通话。乌克兰问题是核心议题，但讨论范围涵盖多个领域。这次通话紧随美乌会议之后，会议上泽连斯基总统同意实施为期30天的停火。以下是对白宫声明的逐句分析，并结合了俄方声明的相关信 ...

大学里学的知识还真是简单。如统计力学，大学里只需要求配分函数，就啥都有了。 一般理想气体的哈密顿量就是： \hat{H} = \sum_{n=1}^{N} \hat{h}_n = \sum_{n=1}^{N} h_n \hat{a}^{\dag}_n ...

When it comes to robotics globally, China is the focus. In January and February this year, China's industrial robot ...

Ukrainian President Volodymyr Zelensky said he will hold phone talks with US President Donald Trump on Wednesday, the ...

A foreign UN worker was killed and five others seriously injured during the Israeli bombing of their headquarters in the ...