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Most of us grew up believing that gravity is just the mass of two objects attracting each other. We probably still think that, really, since who spends their time reading up on gravity? Well, that’s WRONG.
Our old friend MinutePhysics explains that gravity is actually based on energy and momentum, which means even light has gravity (yeah yeah, extra credit if you already knew that). So basically: Suck it, Newton.
And also? All of your word problems in sixth grade math class were wrong, because they didn’t account for the curvature of the Earth. [MinutePhysics]
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Well, obviously, since mass is energy.
I don’t believe in gravity.
Gravity believes in you.
So when Grindr says a man is more than 12750km away, its a lie?
Presumably they use GPS so they are correct as long as you’re not a mole person and planning on tunnelling.
The most perfect example of this is the sun.. its constantly trying to explode and break apart but the energy those explosions produce create a lot of motion within and a crushing level of gravity, which is why when the fire starts to die the gravity will become stronger and the star will collapse in and create (so thought) a black hole capable of sucking in light years of space further than our solar system.. good bye life as we know it when happens.. (that is the dead simple version, Mr Hawkins does it better)
Actually, as the main sequence star’s fuel is spent/ejected, its gravity will actually become weaker and it will be unable to retain such a high density, resulting in an increase in size.