Why is Einstein’s E=MC2 such a big deal that everyone’s heard of it? How important was that discovery actually, is it like in the top 3 most important discoveries of all time or is it kind of overhyped?
In: 1393
Tl;Dr- This discovery is directly responsible for your smartphone, modern power plants, and nuclear holocaust, and it came about because Einstein was trying to settle a debate in the scientific community.
Hugely important and, to your point, often not discussed enough. So E=MC² represents the relationship between energy and mass. In the years before this theory, scientists agreed that when two or more substances underwent a change (we call this a system), the mass of all the inputs would equal the mass of all outputs – stuff wouldn’t just magically be created or destroyed. But agreeing to this had scientists differing on what the energy output of the system would be.
See, energy had been thought of as mechanically separate and unrelated to mass. The energy a system might output would be entirely dependent on the context of how much it had to begin with and how fast the change was and what the substances were. But in the years leading up to this theory, some scientists start realizing that if you give up on keeping mass the same through a change you can use a similar principle to ensure the energy of the inputs matched the energy output by the system. This meant you had to assume that objects inherently had energy in them.
Now along comes Einstein and he proposes that the relationship between energy and mass is a ratio, where the total energy of a system is equal to the mass times the speed of light squared. If this is true, then mass and energy are the same thing in different forms. Also, it means that everything around you has a LOT of pent up energy just by virtue of existing. And it’s starting to look like big, unstable atoms like Uranium might have A LOT OF ENERGY inside them.
So if you can find out how to convert one of those atoms into energy, a very small thing can give you a lifetime of electricity. And by extension of that, a big explosion if released all at once. Oops, now we have atom bombs.
So long story short, E=MC² gave us the bedrock for the last 100 years of technological advancement, nuclear power, the ability to destroy the planet, and some really cool tools for analyzing light.
Edit: Wow! Thanks for the upvotes! I see some of you confused about the relation between this and cell phones. When we make small computer chips, we need to worry about the boundaries of the circuit not being enough to contain the electrons at the speed in which they’re traveling. Instead of an electron colliding with the silicon boundaries of the circuit, it hits the silicon with such power that the silicon itself converts into energy. This let’s the electrons continue through the barrier and into neighboring circuits. This is called quantum tunneling, and you need to account for it when you want to pack hundreds of thousands of circuits in a black rectangle in someone’s pocket and have them be useful.
Edit2: Holy shit, thank you for the gold!
Edit3: Okay, one more because this question keeps getting asked – Why the C² bit? To understand that, we need to understand how Einstein is approaching this theory. Energy approaches the speed of light (C) the less mass the energized thing has. C is the ceiling for speed it seems like. So an easy way to define energy is by saying it’s equal to C when there’s no mass. But on the other hand, if the mass has any additional kinetic energy to it, we need to represent that too. Again, all energy approaches C the less mass it has. So we end up with Energy = Mass x Speed of Energy x Speed of Mass. A simple way to write this is to group the terms together, so we get E = MxCxC or E = MC².
Edit3.5: This is an ELI5 answer. It glosses over some stuff. There are critiques of my post below that are definitely valid, so I encourage you to discuss and learn more in the comments!
Why is Einstein’s E=MC2 such a big deal that everyone’s heard of it? How important was that discovery actually, is it like in the top 3 most important discoveries of all time or is it kind of overhyped?
In: 1393
Tl;Dr- This discovery is directly responsible for your smartphone, modern power plants, and nuclear holocaust, and it came about because Einstein was trying to settle a debate in the scientific community.
Hugely important and, to your point, often not discussed enough. So E=MC² represents the relationship between energy and mass. In the years before this theory, scientists agreed that when two or more substances underwent a change (we call this a system), the mass of all the inputs would equal the mass of all outputs – stuff wouldn’t just magically be created or destroyed. But agreeing to this had scientists differing on what the energy output of the system would be.
See, energy had been thought of as mechanically separate and unrelated to mass. The energy a system might output would be entirely dependent on the context of how much it had to begin with and how fast the change was and what the substances were. But in the years leading up to this theory, some scientists start realizing that if you give up on keeping mass the same through a change you can use a similar principle to ensure the energy of the inputs matched the energy output by the system. This meant you had to assume that objects inherently had energy in them.
Now along comes Einstein and he proposes that the relationship between energy and mass is a ratio, where the total energy of a system is equal to the mass times the speed of light squared. If this is true, then mass and energy are the same thing in different forms. Also, it means that everything around you has a LOT of pent up energy just by virtue of existing. And it’s starting to look like big, unstable atoms like Uranium might have A LOT OF ENERGY inside them.
So if you can find out how to convert one of those atoms into energy, a very small thing can give you a lifetime of electricity. And by extension of that, a big explosion if released all at once. Oops, now we have atom bombs.
So long story short, E=MC² gave us the bedrock for the last 100 years of technological advancement, nuclear power, the ability to destroy the planet, and some really cool tools for analyzing light.
Edit: Wow! Thanks for the upvotes! I see some of you confused about the relation between this and cell phones. When we make small computer chips, we need to worry about the boundaries of the circuit not being enough to contain the electrons at the speed in which they’re traveling. Instead of an electron colliding with the silicon boundaries of the circuit, it hits the silicon with such power that the silicon itself converts into energy. This let’s the electrons continue through the barrier and into neighboring circuits. This is called quantum tunneling, and you need to account for it when you want to pack hundreds of thousands of circuits in a black rectangle in someone’s pocket and have them be useful.
Edit2: Holy shit, thank you for the gold!
Edit3: Okay, one more because this question keeps getting asked – Why the C² bit? To understand that, we need to understand how Einstein is approaching this theory. Energy approaches the speed of light (C) the less mass the energized thing has. C is the ceiling for speed it seems like. So an easy way to define energy is by saying it’s equal to C when there’s no mass. But on the other hand, if the mass has any additional kinetic energy to it, we need to represent that too. Again, all energy approaches C the less mass it has. So we end up with Energy = Mass x Speed of Energy x Speed of Mass. A simple way to write this is to group the terms together, so we get E = MxCxC or E = MC².
Edit3.5: This is an ELI5 answer. It glosses over some stuff. There are critiques of my post below that are definitely valid, so I encourage you to discuss and learn more in the comments!
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