Reversible computing: Difference between revisions

Revision as of 07:40, 10 August 2023

Revision as of 22:38, 10 August 2023

Line 20:

{{Unreferenced section|date=July 2022}}

Landauer's principle (and indeed, the [[second law of thermodynamics]] itself) can also be understood to be a direct [[logical consequence]] of the underlying [[CPT symmetry|reversibility of physics]], as is reflected in the [[Hamiltonian mechanics|general Hamiltonian formulation of mechanics]], and in the [[time evolution|unitary time-evolution operator]] of [[quantum mechanics]] more specifically.<ref>{{Cite journal |lastlast1=Frank |firstfirst1=Michael P. |last2=Shukla |first2=Karpur |date=June 1, 2021 |title=Quantum Foundations of Classical Reversible Computing |url=https://www.mdpi.com/1099-4300/23/6/701 |journal=Entropy |language=en |volume=23 |issue=6 |pages=701 |doi=10.3390/e23060701 |issn=1099-4300 |pmc=8228632 |pmid=34206044 |doi-access=free }}</ref>

The implementation of reversible computing thus amounts to learning how to characterize and control the physical dynamics of mechanisms to carry out desired computational operations so precisely that we can accumulate a negligible total amount of uncertainty regarding the complete physical state of the mechanism, per each logic operation that is performed. In other words, we would need to precisely track the state of the active energy that is involved in carrying out computational operations within the machine, and design the machine in such a way that the majority of this energy is recovered in an organized form that can be reused for subsequent operations, rather than being permitted to dissipate into the form of heat.

Line 28:

Today, the field has a substantial body of academic literature behind it. A wide variety of reversible device concepts, [[logic gate]]s, [[electronic circuit]]s, processor architectures, [[programming language]]s, and application [[algorithm]]s have been designed and analyzed by [[physicist]]s, [[electrical engineer]]s, and [[computer scientist]]s.

This field of research awaits the detailed development of a high-quality, cost-effective, nearly reversible logic device technology, one that includes highly energy-efficient [[clocking]] and [[synchronization]] mechanisms, or avoids the need for these through asynchronous design. This sort of solid engineering progress will be needed before the large body of theoretical research on reversible computing can find practical application in enabling real computer technology to circumvent the various near-term barriers to its energy efficiency, including the von Neumann–Landauer bound. This may only be circumvented by the use of logically reversible computing, due to the [[Second Law of Thermodynamics|second law of thermodynamics]].<ref>{{Cite journal |last=Frank |first=Michael P. |date=2018 |editor-last=Kari |editor-first=Jarkko |editor2-last=Ulidowski |editor2-first=Irek |title=Physical Foundations of Landauer’sLandauer's Principle |url=https://link.springer.com/chapter/10.1007/978-3-319-99498-7_1 |journal=Reversible Computation |series=Lecture Notes in Computer Science |volume=11106 |language=en |___location=Cham |publisher=Springer International Publishing |pages=3–33 |arxiv=1901.10327 |doi=10.1007/978-3-319-99498-7_1 |isbn=978-3-319-99498-7|s2cid=52135244 }}</ref>

==Logical reversibility==

Line 74:

* {{cite journal |last1=Lange |first1=Klaus-Jörn |last2=McKenzie |first2=Pierre |last3=Tapp |first3=Alain |title=Reversible Space Equals Deterministic Space |journal=Journal of Computer and System Sciences |date=April 2000 |volume=60 |issue=2 |pages=354–367 |doi=10.1006/jcss.1999.1672 |doi-access=free }}

* Perumalla K. S. (2014), ''Introduction to Reversible Computing'', [[CRC Press]].

* {{cite book |doi=10.1145/1062261.1062335 |chapter=Time, space, and energy in reversible computing |title=Proceedings of the 2nd conference on Computing frontiers - CF '05 |year=2005 |last1=Vitányi |first1=Paul |pages=435435–444 |isbn=1595930191 |s2cid=5252384 }}

==External links==