Thank you. Here is a link to the article in question. Unfortunately I don't wish to spend $32 on buying it in its entirety, but the abstract gives the general idea. It looks as though the heat produced by erasing a bit of information has been experimentally detected via what looks like some delicate measurements.
(Note - this doesn't indicate that any information is actually being destroyed! The bit in question has been turned from the state of a molecule into heat radiation or thermal motion, so unitarity isn't violated :-) http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html<http://www.nature.com/search/executeSearch?sp-advanced=true&sp-m=0&siteCode=default&sp-q=&sp-p=all&sp-q-2=Berut&sp-p-2=all&sp-q-3=&sp-p-3=all&sp-q-4=483&sp-q-5=&sp-q-6=187&sp-q-10=&sp-q-11=&sp-q-12=&sp-start-month=&sp-start-year=&sp-end-month=&sp-end-year=&sp-date-range=0&sp-q-8=&sp-s=&sp-c=25> Experimental verification of Landauer's principle linking information and thermodynamics - Antoine Bérut<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#auth-1> , - Artak Arakelyan<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#auth-2> , - Artyom Petrosyan<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#auth-3> , - Sergio Ciliberto<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#auth-4> , - Raoul Dillenschneider<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#auth-5> - & Eric Lutz<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#auth-6> - Affiliations<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#affil-auth> - Contributions<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#contrib-auth> - Corresponding author<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#corres-auth> Nature 483,187-189(08 March 2012)doi:10.1038/nature10872 Received 11 October 2011 Accepted 17 January 2012 Published online 07 March 2012 Article tools - Citation<http://www.nature.com/nature/journal/v483/n7388/ris/nature10872.ris> - Reprints<https://s100.copyright.com/AppDispatchServlet?publisherName=NPGR&publication=Nature&title=Experimental+verification+of+Landauer%2F%26%23x27%3Bs+principle+linking+information+and+thermodynamics&contentID=10.1038%2Fnature10872&volumeNum=483&issueNum=7388&numPages=3&pageNumbers=pp187-189&orderBeanReset=true&publicationDate=2012-03-07&author=Antoine+B%26%23x000E9%3Brut%2C+Artak+Arakelyan%2C+Artyom+Petrosyan%2C+Sergio+Ciliberto%2C+Raoul+Dillenschneider%2C+Eric+Lutz> - Rights & permissions<https://s100.copyright.com/AppDispatchServlet?publisherName=NPG&publication=Nature&title=Experimental+verification+of+Landauer%2F%26%23x27%3Bs+principle+linking+information+and+thermodynamics&contentID=10.1038%2Fnature10872&volumeNum=483&issueNum=7388&numPages=3&pageNumbers=pp187-189&publicationDate=2012-03-07&author=Antoine+B%26%23x000E9%3Brut%2C+Artak+Arakelyan%2C+Artyom+Petrosyan%2C+Sergio+Ciliberto%2C+Raoul+Dillenschneider%2C+Eric+Lutz> - Article metrics<http://www.nature.com/nature/journal/v483/n7388/nature10872/metrics> In 1961, Rolf Landauer argued that the erasure of information is a dissipative process1<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#ref1>. A minimal quantity of heat, proportional to the thermal energy and called the Landauer bound, is necessarily produced when a classical bit of information is deleted. A direct consequence of this logically irreversible transformation is that the entropy of the environment increases by a finite amount. Despite its fundamental importance for information theory and computer science2<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#ref2>, 3<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#ref3>, 4<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#ref4>, 5<http://www.nature.com/nature/journal/v483/n7388/full/nature10872.html#ref5>, the erasure principle has not been verified experimentally so far, the main obstacle being the difficulty of doing single-particle experiments in the low-dissipation regime. Here we experimentally show the existence of the Landauer bound in a generic model of a one-bit memory. Using a system of a single colloidal particle trapped in a modulated double-well potential, we establish that the mean dissipated heat saturates at the Landauer bound in the limit of long erasure cycles. This result demonstrates the intimate link between information theory and thermodynamics. It further highlights the ultimate physical limit of irreversible computation. On 20 March 2014 12:09, L.W. Sterritt <[email protected]> wrote: > Liz, > Discussion of this issue: Berut et al, Experimental verification of > Landauer's principle linking information and thermodynamics, Nature > *483,*187-189 (2012). > > Lanny Sterritt > > On Mar 19, 2014, at 1:53 PM, LizR <[email protected]> wrote: > > On 20 March 2014 00:54, Edgar L. Owen <[email protected]> wrote: > >> Brent, >> >> If information is not being lost then the amount of information in the >> universe is increasing at a tremendous rate as new events occur, and has >> been since the beginning. So where is all that new information being >> stored? How can ever increasing amounts of information be being stored in >> the SAME amount of matter states? >> >> As far as I know, unitary evolution in QM implies that the information > content of the universe remains constant. This is why entropy is emergent, > for example, even though it appears on the macroscale to change the amount > of order and disorder. Since the laws of physics are time agnostic at the > fundamental level (bar the usual caveat involving CPT violation) this is to > be expected. You couldn't play physical scenarios backwards even in theory > if information was being created, and the evolution of the wave function > wouldn't be unitary if it was being lost. Hence it stays constant.. > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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