简介:【原文】Butlet'sstepbackforasecondhereandexplainwhatgravitationalwavesactuallyare.AccordingtoEinstein'stheory,thefabricofspace-timecanbecomecurvedbyanythingmassiveintheUniverse.Whencataclysmiceventshappen,suchasblackholesmergingorstarsex-ploding,thesecurvescanrippleoutelsewhereasgravitationalwaves,justlikeifsomeonehaddroppedastoneinapond.BythetimethoseripplesgettousonEarth,they'retiny(aroundabillionthofthediam-eterofanatom),whichiswhyscientistshavestruggledforsomanyyearstofindthem.--NewYorkTimes.
简介:“病”的本义,今或作重病义,或作疾病义。通过对《诗经》等八部早期上古文献中的“病”、“疾病”用例考察,发现早期疾病义都用“疾”,“病”不用作疾病义,更无重病义;“疾病”连用,其“病”为形容词的危重义。进而通过对八部上古文献中“病”、“疾病”所有词义及其训诂的梳理,可定“病”的本义是困苦义。