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How we know the universe is flat
Description
Cosmic radiation and the distribution of matter across space teach us that the geometric shape of the universe is flat, rather than curved like a sphere. By analyzing minute temperature fluctuations from the early universe and calculating the density of energy and matter, scientists are able to determine the ultimate fate of the universe and the nature of its expansion.
Original title
איך אנחנו יודעים שהיקום שטוח?
הקרינה הקוסמית ופיזור החומר במרחב מלמדים אותנו כי צורתו הגיאומטרית של היקום היא שטוחה, ולא עקומה כמו כדור. באמצעות ניתוח של שינויי טמפרטורה זעירים בראשית היקום וחישוב צפיפות האנרגיה והחומר, המדענים מצליחים לקבוע את גורלו של היקום ואת אופן התרחבותו.
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