Problem: In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg's uncertainty principle formulated in 1927, predict a fundamental limit within which instantaneous position and momentum, or energy and time can be measured. This has far reaching consequences on the "emptiness" of space between particles. In the late 20th century, so-called virtual particles that arise spontaneously from empty space were confirmed.
What in the late 20th century did Dirac theorize can be measured?
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Answer: unanswerable


Problem: A major feature is the calypso competition. Calypso music, originating in Trinidad, uses syncopated rhythm and topical lyrics. It offers a medium in which to satirise local politics, amidst the general bacchanal. Calypso tents, also originating in Trinidad, feature cadres of musicians who perform biting social commentaries, political exposés or rousing exhortations to "wuk dah waistline" and "roll dat bumper". The groups compete for the Calypso Monarch Award, while the air is redolent with the smells of Bajan cooking during the Bridgetown Market Street Fair. The Cohobblopot Festival blends dance, drama and music with the crowning of the King and Queen of costume bands. Every evening the "Pic-o-de-Crop" Show is performed after the King of Calypso is finally crowned. The climax of the festival is Kadooment Day celebrated with a national holiday when costume bands fill the streets with pulsating Barbadian rhythms and fireworks.
What is the climax of the festival called?
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Answer: Kadooment Day


Problem: The most important demographic influence in the modern Portuguese seems to be the oldest one; current interpretation of Y-chromosome and mtDNA data suggests that the Portuguese have their origin in Paleolithic peoples that began arriving to the European continent around 45,000 years ago. All subsequent migrations did leave an impact, genetically and culturally, but the main population source of the Portuguese is still Paleolithic. Genetic studies show Portuguese populations not to be significantly different from other European populations.
What is the main population source of the Portuguese people?
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Answer:
Paleolithic