Topic: Total number of bitcoins will DECREASE - page 4. (Read 6542 times)

I'm a bitcoin investor. But I know it can be done. In about a few hundred years, at least, up to a few billion years.

Does that question even make sense?

The concept of temperature is a human abstraction.  A useful definition for temperature is:

   "Temperature is the thing that's the same for two objects, after they've been in contact long enough."  [1]

Physicists then build up mathematical models on top of this definition (and other definitions) that explain what we observe in nature--models such as Boltzmann Factors, the Equipartition Theorem, and even things like the Bose-Einstein and Fermi-Dirac distributions.  But the crazy thing is that none of the parameters of physics (temperature, force, energy, etc) are real in the sense that the computer I am typing on is real.  They are all just useful abstractions that help us explain what we see in nature.  


Jonald: purchase the book "Feynman Lectures on Computation" by R.P. Feynman.  It is fantastic, it will answer a lot of your questions, and it will give you a bunch of new ideas!


[1] DV Schroeder, "Introduction to Thermal Physics," Addison-Wesley Longman, 2000.  

One thing that most people don't seem to understand is that after 21 million Bitcoins have been produced, the TOTAL number of Bitcoins in circulation will decrease in a LINEAR fashion each year.  Why? Because a consistent number of people (maybe 0.05%) will always - ALWAYS - lose their private keys.  This is inevitable.

So with the number of Bitcoins DECLINING (after 21 million) and the demand RISING, classical economics tells us that the price will SURGE.

What is then, the smallest theoretical unit by
which to measure temperature?  

There is no such smallest unit (precision) for temperature*.   However it does not matter as the only form of cooling which would not require the expenditure of energy would be to passively radiate it to the outside environment.  In this case that would be open space and the background temperature is ~3K.   To cool the device below the ambient temp would require the expenditure of energy.  As the textbook example indicates you could use a heat pump but that would negate the benefits of the improved efficiency.

The quote should probably have said "near absolute zero" indicating a high conductivity passive radiator which keeps the computer within fraction of a degree of the background temperature of space and use a K value of ~3K for the energy requirements.


* On edit: It looks like Planks Temperature would indicate the smallest unit of temperature is ~7x10^-33 K although this doesn't materially change the facts.

Who wants to try cracking a bitcoin address?

What is then, the smallest theoretical unit by
which to measure temperature?  

A quick google search turned this up.

http://en.wikipedia.org/wiki/Landauer's_principle


Way off the original topic of the thread, but fascinating stuff.
What is unclear to me about Boltzmann's prinicple, (from
which Landauer's principle is derived) is how there are only a certain number of micro states,
because couldn't temperature be anything?
Or is it a discrete measurement?

In otherwords, is temperature a discrete thermondynamic
value?

Maybe our phd in physics friend can explain further.

thanks for the book reference 

yes, Boltzmann constant multiplied by
circuit temperature, which is why
the graphic says "cooled to absolute zero".

Perhaps the image should be a frozen sun,
nes pa?

But... Shor's algo can be applied to ECDSA right?

Which uses a hash function within it...

Yes.

Create backups.

They are boring for hashing algorithms as Shor's algorithm is not applicable against cryptographic hashes.

P.S. why would quantum computers be "boring" ?

Nonetheless, the discussion of how quantum computers relate to breaking sha 256 is pretty interesting.

The image above with the solar system sized "perfect-computer" is cute, but it lacks detail.  What's the valuation of "least engery possible to record a change of state"?

One of the consequences of the second law of thermodynamics is that a certain amount of energy is necessary to represent information. To record a single bit by changing the state of a system requires an amount of energy no less than kT, where T is the absolute temperature of the system and k is the Boltzman constant. (Stick with me; the physics lesson is almost over.)

Given that k = 1.38×10-16 erg/°Kelvin, and that the ambient temperature of the universe is 3.2°Kelvin, an ideal computer running at 3.2°K would consume 4.4×10-16 ergs every time it set or cleared a bit. To run a computer any colder than the cosmic background radiation would require extra energy to run a heat pump.

Now, the annual energy output of our sun is about 1.21×1041 ergs. This is enough to power about 2.7×10^56 single bit changes on our ideal computer; enough state changes to put a 187-bit counter through all its values. If we built a Dyson sphere around the sun and captured all its energy for 32 years, without any loss, we could power a computer to count up to 2^192. Of course, it wouldn't have the energy left over to perform any useful calculations with this counter.

But that's just one star, and a measly one at that. A typical supernova releases something like 10^51 ergs. (About a hundred times as much energy would be released in the form of neutrinos, but let them go for now.) If all of this energy could be channeled into a single orgy of computation, a 219-bit counter could be cycled through all of its states.

These numbers have nothing to do with the technology of the devices; they are the maximums that thermodynamics will allow. And they strongly imply that brute-force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space.

While I do agree that the total number of spendable Bitcoins would decrease, I disagree that it would be in a linear fashion. Those who made the mistake in the past are unlikely to do so again and the experienced veterans are unlikely to lose their keys so to me it seems more like an exponential decay curve as the rate of change of total spendable coins. Nonetheless, as long as other market factors are unaffected price should logically rise as supply decreases.