2015 saw us complete our exploration of all nine planets (including dwarf planet Pluto) in our solar system.
NASA
2015 was a year where we expanded our view of the universe, embraced new technologies and got a hint of the profound changes to come.
Albert Einstein wrestled with unifying gravity with electromagnetism and quantum mechanics until his dying days.
Oren Jack Turner/Wikimedia Commons
After the triumph of general relativity, Albert Einstein spent the rest of his life chasing a unified theory, which eluded him right up until the end.
Hyperspace may one day be a reality.
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Many people think relativity puts a hard speed limit on the universe, but it actually opens up the possibility of faster-than-light travel - if we can overcome some significant practical hurdles.
General relativity isn’t only a powerfully descriptive theory, but there’s a beauty in its elegance.
Einstein’s theory of general relativity is a triumph of reason and imagination, of art and science, with a profound beauty of its own.
Struggle to understand modern physics? Blame Einstein.
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Space, time and space-time: it’s all relative.
Take my radically intuitive theory and ‘poof’, general relativity will be disproved.
Shutterstock/Richard Peterson
General relativity challenges our intuitive conception of how space and time work, which might explain why it’s such a popular target for crank theorists.
It’s possible that had Einstein not conceived of general relativity, then we’d still be at a loss to explain gravity to this day.
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Special relativity was inspired, but it took true genius to conceive of general relativity. Had Einstein not come up with it, it may have taken decades for us to figure it out.
You can feel the weight of an object on Earth because of its mass. But what is mass?
Flickr/Jeremy Brooks
We talk about mass all the time but what is it that actually gives an object mass? And why do some things have mass and others have no mass at all?
General relativity didn’t happen overnight, but took several steps to come to fruition.
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This month is the centenary of the general theory of relativity. But how did we get from the absolutism of Newton to the relativity of Einstein?