What is the universe made of?
Astronomers face an embarrassing conundrum: they don't know what 95% of the universe is made of. Atoms, which form everything we see around us, only account for a measly 5%. Over the past 80 years it has become clear that the substantial remainder is comprised of two shadowy entities – dark matter and dark energy. The former, first discovered in 1933, acts as an invisible glue, binding galaxies and galaxy clusters together. Unveiled in 1998, the latter is pushing the universe's expansion to ever greater speeds. Astronomers are closing in on the true identities of these unseen interlopers. |
/ How DID Life Begin?
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In 1905—seen by many as a "miracle year" for the theorist—Einstein had four papers published in the Annalen der Physik, one of the best known physics journals of the era. The four papers focused on the photoelectric effect, Brownian motion, the special theory of relativity (the most widely circulated of the write-ups) and the matter/energy relationship, thus taking physics in an electrifying new direction. In his fourth paper, Einstein came up with the equation E=mc2, suggesting that tiny particles of matter could be converted into huge amounts of energy, foreshadowing the development of atomic power.
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Are there other universes? |
What is consciousness? |
Our universe is a very unlikely place. Alter some of its settings even slightly and life as we know it becomes impossible. In an attempt to unravel this "fine-tuning" problem, physicists are increasingly turning to the notion of other universes. If there is an infinite number of them in a "multiverse" then every combination of settings would be played out somewhere and, of course, you find yourself in the universe where you are able to exist. It may sound crazy, but evidence from cosmology and quantum physics is pointing in that direction.
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We're still not really sure. We do know that it's to do with different brain regions networked together rather than a single part of the brain. The thinking goes that if we figure out which bits of the brain are involved and how the neural circuitry works, we'll figure out how consciousness emerges, something that artificial intelligence and attempts to build a brain neuron by neuron may help with. The harder, more philosophical, question is why anything should be conscious in the first place. A good suggestion is that by integrating and processing lots of information, as well as focusing and blocking out rather than reacting to the sensory inputs bombarding us, we can distinguish between what's real and what's not and imagine multiple future scenarios that help us adapt and survive.
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