š
Original date posted:2018-01-20
š Original message:On 2018-01-17 at 22:31:52 +0000, Jefferson Carpenter
<jeffersoncarpenter2 at gmail.com> wrote:
>Bitcoin's difficulty will be maxed out within about 400 years, by
>Moore's law.
On 2018-01-19 at 20:54:52 +0000, Jefferson Carpenter
<jeffersoncarpenter2 at gmail.com> wrote:
>In other words, max difficulty for SHA256 might be significantly faster
>than forcing the first 256 bits of a SHA512 hash...
āMooreās lawā is not a law of nature. Indeed, chipmakers began bumping
up against the limitations of *actual* natural laws about 15ā20 years
ago. That is why instead of increasing core clock, they play the tricks
which opened the way for Meltdown and Spectre. Feature size, and thus
transistor counts, will soon enough run into physical limitations, too.
But the scenario you describe does not even require such a discussion.
2^256 work for brute force is on the order of 10^77 hashes. For the
number of atoms in the observable universe, Iāve seen estimates ranging
from 10^78 to 10^82. Thus, you are suggesting that within 400 years,
computers will be able to compute one hash for every myriad of atoms in
the observable universeāperhaps one hash for every *ten* atoms.
Moreover, you suggest that twenty-fourth century computers will do this
fast enough to meet Bitcoinās ten-minute target rate.
Such a proposition bypasses science, leaps over science fiction, and
lands in the realm of religion. Perhaps a deity could do thisāusing a
computer made of other than matter, powered by other than energy.
Humans will *never* be capable of such a feat: Not now, and not in a
billion years. Certainly not a mere four centuries hence!
(I do not here positively exclude the possibility, however slim, that
mathematical breakthroughs may yield a preimage attack on SHA-256 which
is significantly better than bruteforce. I *do* positively declare it
impossible that Earth-beings will ever be capable of performing 2^256
work. Or even 2^128 work, for that matter.)
--
nullius at nym.zone | PGP ECC: 0xC2E91CD74A4C57A105F6C21B5A00591B2F307E0C
Bitcoin: bc1qcash96s5jqppzsp8hy8swkggf7f6agex98an7h | (Segwit nested:
3NULL3ZCUXr7RDLxXeLPDMZDZYxuaYkCnG) (PGP RSA: 0x36EBB4AB699A10EE)
āāIf youāre not doing anything wrong, you have nothing to hide.ā
No! Because I do nothing wrong, I have nothing to show.ā ā nullius
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