In theoretical physics, scalar field theory can refer to a relativistically invariant classical or quantum theory of scalar fields. A scalar field is invariant under any Lorentz transformation. The only fundamental scalar quantum field that has been observed in nature is the Higgs field. However, scalar quantum fields feature in the effective field theory descriptions of many physical phenomena. An example is the pion, which is actually a pseudoscalar.
Artificial intelligence (AI) is the intelligence of machines or software, as opposed to the intelligence of human beings or animals. AI applications include advanced web search engines (e.g., Google Search), recommendation systems (used by YouTube, Amazon, and Netflix), understanding human speech (such as Siri and Alexa), self-driving cars (e.g., Waymo), generative or creative tools (ChatGPT and AI art), and competing at the highest level in strategic games (such as chess and Go).
Coimbra (koʊˈɪmbrə, also USkuˈ-,_ˈkwɪmbrə, UKˈkɔɪmbrə, kuˈĩbɾɐ or ˈkwĩbɾɐ) is a city and a municipality in Portugal. The population of the municipality at the 2011 census was 143,397, in an area of . The fourth-largest agglomerated urban area in Portugal after Lisbon, Porto, and Braga, it is the largest city of the district of Coimbra and the Centro Region. About 460,000 people live in the Região de Coimbra, comprising 19 municipalities and extending into an area of .
The Korean alphabet, known as Hangul (ˈhɑːnguːl ; ) in South Korea and Chosŏn'gŭl () in North Korea, is the modern official writing system for the Korean language. The letters for the five basic consonants reflect the shape of the speech organs used to pronounce them, and they are systematically modified to indicate phonetic features; similarly, the vowel letters are systematically modified for related sounds, making Hangul a featural writing system.