
Simon's Algorithm - keyboardman
https://leimao.github.io/blog/Simon-Algorithm/
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Gehinnn
I don't understand the problem. x and y are free, so you can choose x=y. Then
obviously, f(x)=f(y). Then it should follow x=x xor c, thus c=0. Or did they
forget to claim that x and y are different?

~~~
rymohr
You are confusing equality and equivalence.

It’s easy to do. Einstein did the same thing with E=mc2.

Equality is a matter of identity. Equivalence is a matter of behavior.

The speed of light is not an absolute constant as Einstein believed. C just
represented the speed that light can travel as a relationship between energy
and mass.

My favorite form of the equation is C equals the square root of energy divided
by mass.

Behaviorally all that means is that as the energy to mass ratio goes up, the
speed of light goes up. And as the mass to energy ratio goes up, the speed of
light goes down. Hence time dilation, black holes, etc.

~~~
cyphar
> The speed of light is not an absolute constant as Einstein believed. C just
> represented the speed that light can travel as a relationship between energy
> and mass. My favorite form of the equation is C equals the square root of
> energy divided by mass. Behaviorally all that means is that as the energy to
> mass ratio goes up, the speed of light goes up. And as the mass to energy
> ratio goes up, the speed of light goes down. Hence time dilation, black
> holes, etc.

That isn't what's happening in relativity. That might be a neat trick for you
to remember whether an effect is dilation or contraction (though I personally
find it more confusing), but the speed of light does not change in different
frames of reference -- this is a fundamental property of relativity (and is an
assertion by Einstein, who argued that the speed of light derived from
Maxwell's equations means that if light functions in all frames of reference
it must propagate at the same speed).

And while the mass-energy equivalence equation you mentioned is used in the
way you described (rearranging it to have the speed of light as one term),
it's actually used explicitly because the value must be constant -- the
implication being that mass-energy is an invariant in relativity (though
technically this derivation is backwards -- E=mc² is the conclusion you reach
after assuming mass-energy conservation).

Relativity is already unintuitive enough, I personally find that adding
incorrect-but-seemingly-intuitive explanations probably hurts your
understanding more than it helps.

