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Questions tagged [landauers-principle]

23 questions
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If we had a "perfectly efficient" computer and all the energy in the Milky-way available, what number could it count to?

The idea for this question comes from an example in cryptography, where supposedly 256-bit symmetric keys will be enough for all time to come (brute-forcing a 256-bit key is sort-of equivalent to counting to $2^{255}$, with some constant in front of…
cooky451
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Maximum theoretical data density

Our ability to store data on or in physical media continues to grow, with the maximum amount a data you can store in a given volume increasing exponentially from year to year. Storage devices continue to get smaller and their capacity gets bigger.…
tylerl
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Is there a thermodynamic limit on how efficiently you can solve a Rubik's cube?

Suppose I build a machine which will be given Rubik's cubes that have been scrambled to one of the $\sim 2^{65}$ possible positions of the cube, chosen uniformly at random. Is it possible for the machine to solve the cubes without giving off any…
Mark Eichenlaub
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How does Landauer's Principle apply in quantum (and generally reversible) computing

I understand that a reversible computer does not dissipate heat through the Landauer's principle whilst running - the memory state at all times is a bijective function of the state at any other time. However, I have been thinking about what happens…
Selene Routley
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Foundation of Landauer's principle

I have asked this on CS subsite but since there was no reply yet and the question is also somewhat related to physics, I think it will be appropriate to post here as well. Landauer's principle states the minimum possible amount of energy required to…
P1xelPainter
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Is there a trade-off between computation speed and heat creation in relation to the Landauer Limit?

In this article, an experiment is referenced in which information was converted into energy via erasure. It is said that the slower the erasure took place, the less energy was released, and that the Landauer limit was approached as the length of the…
DJG
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Is it necessary to assume that equivalent microstates cannot get transformed into inequivalent microstates to derive the Landauer principle?

The Landauer erasure principle states that to erase a bit of information from a system, the entropy of the environment will be increased by at least $k_B\log2$, or equivalently, it costs at least an amount $k_BT\log2$ of energy to erase a bit of…
doetoe
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Is the Landauer limit reversible

As I understand it, the Landauer limit, $kTln(2)$, is the minimum amount of energy to erase a bit. Is it also the minimum amount to create a bit? I'm asking statistical, like Avogadro's number of bits, i.e., $RTln(2)$. My thinking: $RTln(2)$ is…
Incredible II
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How practical is the Landauer limit to actual computing (including distant future)?

Landauer's Principle is often presented as a fundamental limit of efficiency for classical computing. It states that in order to erase one bit of information, at least the following amount of heat has to be released: $$ E = k_BT\ln 2 $$ It's very…
MeyCJey
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Landauers Principle Derivation

I read about Landauer's principle and was wondering about the implications from it's original derivation. Landauer derived his principle straight foward from the second law, but I see people favoring derivations by Shizume or Piechocinska, who…
Peter Sanctus
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Landauer limit - cost to avoid changing a bit already equal to desired value

If I have a bit and I do not know what the current value is, is it possible to use less energy than $E_b = k_b T \ln(2)$ so that if the bit value is already equal to what you want, you don't waste energy by setting it? My guess is no:…
Bob
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Is Landauer’s principle an approximation?

According to Wikipedia, Landauer’s principle follows from the second law of thermodynamics. However, the second law of thermodynamics is an approximation: there is an extremely small probability that entropy decreases. Does it follow that Landauer’s…
Riemann
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Is any energy converted to information when taking a photograph?

I am curious about the relationship between energy and information. I have only a beginner's knowledge, having read Shannon's original paper and a little about Landauer's limit which states that the minimum amount of energy required to erase 1 bit…
Jackson Walters
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Is the value $k \ln 2$ the largest or the smallest entropy that a single particle can carry?

Sorry, but I lost the reference of the author telling this. Is $k \ln 2$ the largest or the smallest entropy that a single particle can carry? And why is this so? EDIT: It was a paper from the 1970s.
KlausK
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Landauer's principle vs Rayleigh–Jeans law

Can we argue based on Landauer's principle that if one bit information is changed inside a blackbody, the total radiated energy should be at least or in order of $kT\ln2$? If it is so, can we also argue that this energy should be distributed over…
Omar Shehab
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