There's no single, universally agreed-upon "beginning" of time. Our current understanding of physics suggests a point called the Big Bang, but what, if anything, came before it remains a mystery.
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Photonic chips, similar to microchips but using light instead of electricity, can process information significantly faster and more energy-efficiently than their electronic counterparts.
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Quantum entanglement allows two particles to be linked regardless of the distance separating them, meaning a change in one instantly affects the other – even if they're light-years apart.
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Spectra, in the context of physics and chemistry, are often unique "fingerprints" for substances. No two substances have exactly the same spectral signature.
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Relativity predicts that time passes slower for objects moving faster relative to a stationary observer – a phenomenon known as time dilation.
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Some superconductors, when cooled below their critical temperature, exhibit the Meissner effect, completely expelling magnetic fields from their interior.
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The grandfather paradox, a classic time travel conundrum, is actually a plot device more than a scientifically sound problem, as it assumes a fixed, linear timeline that might not exist in theoretical models of time travel.
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Wormholes, if they exist, could potentially allow for faster-than-light travel, but traversing one might require navigating exotic matter with negative mass-energy density – a substance we've never observed.
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String theory requires more than the usual three spatial dimensions and one time dimension; it proposes the existence of extra, curled-up spatial dimensions that are too small to observe directly.
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String theory requires more than the usual three spatial dimensions and one time dimension; it posits the existence of extra, curled-up spatial dimensions unseen at macroscopic scales.
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The efficiency of a heat engine is fundamentally limited by the temperatures at which it operates; you can never completely convert heat into work.
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Quantum entanglement allows two particles to be instantaneously correlated, regardless of the distance separating them – a phenomenon Einstein famously called "spooky action at a distance."
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