The Physics of Brute Force (2016)
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The Physics of Brute Force (2016)
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Re: The Physics of Brute Force (2016)
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Re: The Physics of Brute Force (2016)
#3[deleted]
Re: The Physics of Brute Force (2016)
#4>where 0 Kelvin is defined as a system devoid of energy
This is not true, in quantum mechanics at zero kelvin (so in its fundamental state) a system has a non zero energy. See this: https://en.wikipedia.org/wiki/Quantum_harmonic_oscillator#Ha...
Re: The Physics of Brute Force (2016)
#5> So, we'll run this ideal computer at 2.72548 Kelvin.
The record for lowest temperature is 1e-10 Kelvin and there is no theoretical limit as to how many zeroes can be added. So there is no hard limit, given good enough cooling/thermal isolation, the energy cost can be brought down. In theory, it can be brought down to zero.
Re: The Physics of Brute Force (2016)
#6>where 0 Kelvin is defined as a system devoid of energy This is not true, in quantum mechanics at zero kelvin (so in its fundamental state) a system has a non zero energy. See this: https://en.wikipedia.org/wiki/Quantum_harmonic_oscillator#Ha...
You're right. Zero Kelvin means no _entropy_.
Re: The Physics of Brute Force (2016)
#7>where 0 Kelvin is defined as a system devoid of energy This is not true, in quantum mechanics at zero kelvin (so in its fundamental state) a system has a non zero energy. See this: https://en.wikipedia.org/wiki/Quantum_harmonic_oscillator#Ha...
You're right. Zero Kelvin means no _entropy_.
Is that true either? E.g a metastable glass structure sent to 0k probably still has an entropy?
Re: The Physics of Brute Force (2016)
#8Earlier quoted context omitted.
You're right. Zero Kelvin means no _entropy_.
Is that true either? E.g a metastable glass structure sent to 0k probably still has an entropy?
I don't know for metastable glass but you can read about the third law of thermodynamics which address the question of entropy and low temperature: https://en.wikipedia.org/wiki/Third_law_of_thermodynamics
Especially this might interest you:
"A classical formulation by Nernst (actually a consequence of the Third Law) is:
It is impossible for any process, no matter how idealized, to reduce the entropy of a system to its absolute-zero value in a finite number of operations."
Re: The Physics of Brute Force (2016)
#9> So, we'll run this ideal computer at 2.72548 Kelvin. The record for lowest temperature is 1e-10 Kelvin and there is no theoretical limit as to how many zeroes can be added. So there is no hard limit, given good enough cooling/thermal isolation, the energy cost can be brought down. In theory, it can be brought down to zero.
This is addressed:
> To run a computer cooler than that would require a heat pump, which means adding additional energy to the system than what is needed for our computation.
Re: The Physics of Brute Force (2016)
#10The problem is I don't need to search the whole key space. Even with very goods encryption algorithms, there are faster attacks. They're not FAST attacks, mind you, so the keys are safe, but they are FASTer.